Development of TVV-1000-4 turbine generator relay protection

Contents

CONTENTS

Certificate Project Statement

Contents

Summary

List of conditional abbreviations

Introduction

Process Part

Electrical power generation technology at NPP

Primary Circuit Thermal Diagram

Emergency core cooling system

Secondary Circuit Thermal Diagram

Main electrical diagram of primary connections

Purpose of TVB turbine generator

Technical specifications

Structural units of TVB generator

Electrical part

Relay protections of TVB generator

Calculation

Source Data

Calculation of system resistance in different modes

Calculation of currents of K.Z

Longitudinal differential protection of generator

Transverse differential protection of generator

Protection against voltage increase in generator stator winding

Asynchronous protection

Ground fault protection in generator stator winding

Two-stage remote protection of generator

Protection against asymmetric overloads

Protection against symmetrical overloads

Complex of protection of the TVV-1000 generator of the ShE1110M type

Purpose of the ShE1110M complex

Technical data

Device and principle of work of the ShE1110M complex

Economic part

Organization and planning of production design preparation

Planning of the CPT

Calculation of the cycle duration of the checkpoint and the number of performers

Development of the checkpoint schedule and its optimization

Calculation of the cost estimate for the checkpoint

Calculation of project performance indicators

Use of the economic model to develop the concept of reducing the cost of VVER TOI NPP at the design stage

Safety of life

Organization of occupational safety at the enterprise

Occupational safety in turbine shop

Labor protection during installation and operation of relay protection

Requirement for illumination at workplaces of RPA and T personnel of equipped PCMs

Safety of life in emergency situations

Probable emergencies at NPP

Most likely emergency at NPP

Conclusion

List of literature

Application

Application

Application

Summary

In the diploma design, the relay protections of the TVV10004 turbine generator are designed, which are part of the protection complex of the SHE1110M type based on microprocessors.

The diploma project contains the following parts:

technological;

electrical;

a special project issue;

the economic part;

safety of life activities.

In the technological part of the diploma project, the issue of obtaining electricity at the Rostov NPP was considered.

In the electrical part, relay protections of the stator winding of the TVB10004 turbine generator are designed.

In a special part, I briefly considered the SE1110M protection complex based on a new element base - microprocessors.

In the economic part, the organization and planning of design preparation of production, as well as the issue of VVER TOI, are considered.

The diploma project considered measures to ensure the safety of personnel with microelectronic equipment and calculated the lighting of the workplace of personnel working with PVEM.

List of conditional abbreviations

NPP - Nuclear Power Plant

TPP - thermal power plant

NPP - nuclear power plant

RCP - Main Circulation Pump

RCC - main circulation circuit

ECCS - emergency core cooling system

RDES - standby diesel power station

GPU - main steam gate valve

PSD - pulse safety device

HPC - high pressure cylinder

LPC - low pressure cylinder

WBS - Steam Superheater Separator

ERP - turning gear

CEP - condensate electric pump

EP - start-up ejector

EU - seal ejector

UDP - demineralizing unit

IPA Low Pressure Heater

OPN - main feed pump

TPN - Turbine Feed Pump

AFEP - auxiliary feed electric pump

HPH - high pressure heater

Recovery Boiler - Stop and Control Valves

Maintenance - heat exchanger

MO - pressurizer

KAG - generator package

OPC - open switchgear

AT - communication autotransformer

Short circuit - short circuit

RZA - relay protection and automation

TT - current transformer

ECU - backup device in case of switch failure

CCS - central control panel

FCU - unit control panel

TAPV - three-phase automatic repeated switch-on

APCS - automated process control system

Checkpoint - design preparation of production

Introduction

Electric energy is widely used in all areas of the national economy and in everyday life. This is facilitated by its versatility and ease of use, the possibility of production in large quantities by industrial method and long-distance transmission.

During operation of power systems at electric equipment of power plants, in electric networks and at electric installations of power consumers, damage and abnormal modes may occur that disrupt their operation. Most damage is accompanied by a sharp increase in currents and a decrease in voltage in the elements of the power system.

The current and electric arc generated at the point of damage emit significant amounts of heat and therefore cause large damage, and the decrease in voltage disrupts the stability of parallel operating synchronous generators.

Abnormal modes, accompanied by a decrease in voltage and frequency, also threaten to disturb the synchronism of generators, and those abnormal modes, at which there is an increase in current or voltage above the normal value, create a danger of damage to the equipment.

In order to ensure reliable power supply to consumers, prevent destruction of equipment of electrical installations and maintain stable operation of generators, it is necessary to quickly disconnect the damaged area, as well as timely eliminate the emerging abnormal modes dangerous to the equipment.

In this regard, it becomes necessary to create and use automatic devices that protect generators from the dangerous consequences of damage and abnormal modes.

The purpose of the diploma project is to design the relay protection of the TVB10004 turbine generator based on digital microprocessor protection devices of the SHE1110M type. Digital protections provide both the main functions implemented by analog relay protections and additional ones: they allow you to automate the collection, processing and storage of information from security devices and make the fullest use of their capabilities, have an integrated diagnostic system that does not require periodic testing and a circuit integrity control system.

Currently used microprocessor relay protection devices and automatics have a wide range of setpoints and the possibility of changing the response characteristics in time, direction and phase shift of the measured values.

Process Part

Electrical power generation technology at NPP

The process flow diagram of production of electric energy on the NPP (the drawing 14020465.Z12.091.01.00.P6) includes the following stages of transformation of energy:

obtaining thermal energy by splitting heavy metal nuclei in the core of nuclear reactors at nuclear power plants;

conversion of thermal energy in NPP steam generators with VVER reactor;

converting potential water vapor energy into kinetic energy in a steam turbine nozzle apparatus;

converting the kinetic energy of water vapor into rotational motion of the rotor of the steam turbine and the associated rotor of the electric generator;

generation of alternating electric voltage in the generator stator winding (electromagnetic field of the rotating generator rotor crosses the turns of the generator stator winding, creating a variable EMF - electromotive force in the turns of the stator winding);

increase of alternating voltage in unit transformer from 20 to 500 kV and supply of electric power to consumers via high-voltage lines through open switchgear.

After considering the technology of electric power generation, it is possible to determine the composition of the main equipment of the NPP power unit with the VVER reactor of Donbass NPP:

VVER nuclear reactor -1000;

Steam generator;

Steam turbine K100060/1500;

FA generator;

Unit transformer;

Open switchgear.

1.2. Primary Circuit Thermal Diagram

The thermal diagram of the power unit is two-circuit. The first radioactive circuit consists of one VVER reactor - 1000 and 4 circulation cooling loops. Each circulation loop consists of steam generator, main circulation pump (MCP) and main circulation pipelines Dy = 850 mm. The primary coolant is non-boiling water of high purity at a pressure of 16.0 MPa with the addition of boric acid solution.

The nuclear reactor is an "atomic boiler," heats the water of the first cooling circuit of the reactor core to about 3200C, by means of energy release in the core of the nuclear reactor during fission of the nuclei U235 and transfer of kinetic energy of fission fragments to surrounding atoms and molecules of the medium, radiation capture of neutrons, absorption of gamma quanta and bettaparticles emitted during fission of the nuclei U235 and 35 .

Further, the main circulation pump of the RCP 195M, designed to create coolant circulation in the RCC, for heat removal from the reactor core, the RCP is a vertical centrifugal single-stage pump consisting of a housing, a recessed part, an electric motor and auxiliary systems - pumps the primary coolant through the steam generator PGV1000M (designed to remove heat from the saturated coolant generation 1 and the primary coolant. The type of steam generator is a horizontal single-hull with a submerged heat exchange surface from horizontally located pipes.), where it is cooled to about 280 0С, giving energy to the secondary coolant.

1.3. Emergency core cooling system

Emergency zone cooling system. (active part) is intended for emergency cooldown of the reactor core and subsequent long-term removal of residual heat from the core in case of accidents associated with decompression of the 1 circuit, including termination of pipelines of the main circulation circuit  (RCC) of the DP 850 full section with unimpeded double-sided expiration of the coolant.

The system consists of three independent emergency core cooling channels, each of which is capable of fulfilling the requirements.

Each channel includes emergency cooldown pump, emergency cooldown heat exchanger, pipelines and valves. The emergency boron reserve tank (pit tank) is common for all three channels.

The system also has equipment common to three channels: a pipeline for scheduled cooldown and repair cooldown with valves installed on it and auxiliary pipelines (drains, vents) cut into it.

All three channels of the system provide borated water supply to and under the reactor core, in the repair cooldown mode, water is supplied to the core. The second and third channels are connected to the lines of borated water supply from ECCS hydraulic accumulators, and the first channel to the "cold" and "hot" lines of the first circulation loop.

On the pressure line of the emergency cooldown pump, operational valves, check valves, as well as normally open valves are installed, which provide the necessary directions of medium movement in emergency and scheduled cooldown modes.

Two check valves installed in series, and one normally closed valve with drainage in front of it provide reliable isolation of high pressure from low pressure.

By suction, the system is connected to the containment tank-pit, as well as to the cold and hot line of the RCC (scheduled and repair cooldown line).

In an emergency situation with depressurization of the 1 circuit, the system is connected to the tank tank, in all other cases, water is taken from the RCC.

At the pressure in the primary circuit above 1.5 MPa, the system is reliably disconnected from the RCC near the shutoff valves, which are in a closed position with disassembled electrical control circuits. Valves on the system connection to the containment pit in this mode are open. In the scheduled cooldown mode (pressure in the primary circuit is 1.5 MPa), the valves for communication of the system with the RCC are opened, and the valves for communication of the system with the containment pit are closed.

Thus, combining the functions of the normal operation device and the protective device does not reduce the safety level of the NPP, since the system, regardless of the mode, operates in the same technological sequence, using the same mechanisms and equipment, medium flows do not change their direction. Valves are switched at practically located unit.

Safety valves are installed to protect the equipment, suction pipelines of the system outside the sealed part from overpressure on the planned cooldown line in the sealed part.

The emergency cooldown pump has a recirculation line that ensures testing of the pump and its operation in various modes. A throttle washer is installed on the head of the emergency cooldown pump to ensure stable operation of the unit with a fully decompressed 1 circuit.

In the sealed part, a line for mixing boron solution in the tank is cut into the pressure pipeline, which is intended to prevent delamination of the solution into boric acid and distillate. To allow mixing of water in the tank inside it there is a distribution manifold to which mixing lines from each pump are connected. The manifold is a pipeline with uniformly placed holes, located in the tank and repeating its configuration.

Scheduled and repair cooldown lines are cut into "hot" and "cold" lines, respectively.

The repair cooldown line is designed to remove residual heat with the reactor cover removed and the level in the reactor along the axis of cold branch pipes.

Scheduled and repair cooldown lines are combined into one pipeline, on which a control valve is installed, and which crashes into the suction line of the emergency cooldown pump, in front of the ECCS heat exchanger.

Heat removal from the 1 circuit is carried out using ECCS heat exchanger, in which heat from the water of the 1 circuit is transferred to the service water of essential consumers. Technical water of essential loads is supplied from the spray pool by pumps of essential loads to ECCS heat exchanger, where it is heated and again supplied to the spray pool. Cooling water is supplied to ECCS heat exchanger continuously with constant flow rate. ECCS heat exchanger has bypass from scheduled and repair cooldown line.

Control valve is also installed on bypass. Both control valves are designed to control the cooling rate of the 1 circuit. The emergency cooldown heat exchanger is designed for emergency and planned cooldown of the 1 circuit and removal of residual heat of the core. The coolant enters the annular space from the tank pit, in case of an accident, or from the pipeline of planned and repair cooldown and is cooled by the technical water of group "A," which moves through the tubes countercurrent.

Emergency cooldown pump is combined with pumps of sprinkler system and boron injection system via suction line.

Power supply of operating valves and drives of emergency cooldown pumps is carried out from operating auxiliary transformers or from standby power supply from the power system, and in case of de-energization from RDPP.

The tank-sump of safety systems is an integral part of the containment floor, filled with boron solution, 16 g/kg concentration. The upper part of the tank is formed by an overlap connected to the tank by 3 - m independent drain devices F = 1.0 m2 each. Said overlap is the lower mark of the sealed volume of the shell, with which, by organizing the slopes, it is provided for draining the incoming water into the tank.

When choosing the volume of the tank - pit, the following non-return losses of water supplied to the volume of the containment by emergency pumps were taken into account:

loss of water consumed for filling of emergency systems pipelines,

loss of water forming the film on the walls of the premises,

water loss for evaporation,

loss of water falling into non-drained volumes. These losses are minimized by organizing slopes and drain openings on all flat surfaces (floors at different elevations), overflow openings between rooms, etc.

The total volume of these losses is approximately 300 m3.

The remaining water is sufficient to form a high level (0.7-0.8 m) in the tank pit, which is necessary to prevent the formation of funnels and capture air on the pump suction, as well as to create the necessary overpressure at the suction of emergency pumps, which is confirmed by the experience of commissioning.

Water is supplied from the tank to the suction of safety system pumps via the 3rd independent suction pipelines Dn600 located in the lower part of the tank.

1.4. Secondary Circuit Thermal Diagram

Fresh steam of steam generators is transported to the turbine via four steam pipelines of 630 x 25 diameter by the system of fresh steam pipelines.

Main steam pipelines are protected against pressure increase in them by three protection stages. The function of the first stage is performed by the BROOK, and when their opening (or failure) is prohibited, the BROOK opens. If the first two stages are ineffective, the PSD PSD devices of the steam generators operate.

Conversion of heat energy of steam generated in steam generators into mechanical energy of generator drive rotation is carried out by turbine plant of type K100060/15002 TU 108.105582.

The turbine is intended for work on the double-circuit NPPs in the monoblock with the VVER1000 pressurized water reactor on saturated steam with parameters in front of the MPa lock valve P =5.88 abs. and dryness of Hs =0.995.

Structurally, the turbine is performed according to the 1HPC + 3LPC scheme.

In order to ensure the operation of the last stages of the rotor of no turbine pressure with permissible humidity during the design period, the steam spent in the HPC enters the intermediate steam overheating system, which is designed for separation of steam and its subsequent overheating.

Steam spent in HPC through four steam pipelines is supplied to SPP1000 separator, where up to 10% of moisture (separator) is separated from it, then steam with design dryness degree of 0.999 is supplied successively to superheaters of the first and second stages, where it is overheated to 250 ° С and then through two steam pipelines to LPC turbine. The separator according to the system of trays is drained to the separator collector (one for each WBS) and further to the turbine regeneration system.

The steam used in LPC is supplied to the condensate-vacuum system, which is designed to cool the working medium to the lower temperature of the thermodynamic cycle and create a vacuum in the turbine condenser including three two-way double-flow condensers of the K33160 type turbine.

The condensate of the spent steam in the turbine is pumped from the condensers to the deaeration unit by the main condensate system. The system consists of condensate pumps of the first stage of KSVA1500120 type, condensate pumps of the second stage of KSVA15002402a type, connecting them and the above equipment of pipelines and valves.

Before supply of steam in condensate installation its heating is carried out by the system of regeneration of low pressure which includes three PN12002561A PND1, two PN1400256PA PND2 and on one case of PN30002516ShA and PN300025161UA PND3 and PND4 respectively.

Removal of dissolved gases from feedwater and its supply for steam generator makeup is carried out by a deaeration feeding system, which includes the following equipment:

deaerators of DP3200/185 type, consisting of two storage tanks with a volume of 185 m3, on each of which two columns DP16002 are installed;

two turbine feed pumps (TPN), including a pre-connected single-stage (booster) pump of PD37502 type with a nominal speed of 1800 rpm, connected through a reduction gear box to the turbine drive;

main feed pump of PT337507 type three-stage, double-hull, connected by coupling to turbine drive rotor;

turbine drive - turbine of OK12A type;

two auxiliary feed electric pumps (AFEP) of type PE15085 h;

four filters at the suction of booster pumps, each of which is a cone grid in a cylindrical body.

Regenerative heating of steam generators feed water is carried out by a high-pressure regeneration system, which includes two groups of HPH. In each group there are two PVD6 heaters connected in series by feedwater, and PVD7.

1.5. Main electrical diagram of primary connections

Turbogenerators of TVV10004U3 type (drawing 14020465.Z13.091.02.00.KZ) are used for conversion of mechanical energy into electric energy for power generation in continuous mode.

Generators are three-phase implicit electric machine.

Beginning and ends of stator windings of generators are brought out through end leads. Generators have three linear leads located at the bottom of the end part on the side of the exciter, and six zero leads located at the top of the same end part.

On zero conclusions transformers of current and the transformer of tension are installed (the drawing 1402065.Z13.091.02.00.EZ).

Generators are excited from brushless exciters connected to generator shaft.

In normal operation mode, voltage of 24 kV from three line terminals of generators is supplied via shielded current wires through set of generators (KAG) to unit transformers. KAG consists of generator switch and disconnectors.

The outputs of the unit transformers are connected to the 500 kV switchgear, from the tires of which electricity is supplied to the consumer: VL Budenovskaya, VL Nevinomysk, VL Tikhoretsk, VL Shakhty and VL Yuzhnaya.

Auxiliary operating transformers are connected by unsettles from the generator transformer unit circuit, between the unit transformers and KAG.

Reserve transformers of own needs are connected to tires ORU220 of kV, VL220 of kV powered by calling. Standby transformers are used only in case of damage to the electrical part of the unit.

When the operating auxiliary transformer is damaged, the protection of the operating transformer is activated through the output protection relays of the unit. The electric unit is disconnected with turbine and reactor shutdown. Auxiliary consumers of this transformer switch to power supply from the standby transformer for the planned reactor shutdown.

The 500 kV OPC is connected to the 220 kV OPC by means of an installed communication autotransformer - a set of three single-phase autotransformers of the AODTSTN167000/500/220U1 type with a total power of 3 × 167 MVA with a voltage of 500/220 kV.

At damage of the autotransformer of communication (AT) of 500/220 kV its protection affects shutdown of switches of 500 kV and 220 kV of AT, tires ORU500 of kV and ORU220 of kV of the NPP work separately, and stability of work the EXPERT is not broken.

1.6. Purpose of TVV-1000 turbine generator

Synchronous three-phase turbine generator of TVV10004UZ type (hereinafter referred to as "generator" (drawing 14020465.Z13.091.02.00.KZ)) is designed to generate electricity in a long nominal mode of operation according to GOST 18374 when directly connected to a steam turbine when installed in a closed room at nuclear power plants.

The generator is manufactured in climatic design U category 3 as per GOST 1515069 and GOST 1554370 for operation:

at an altitude of not more than 1000 m;

within ambient air temperatures from + 5 ° С to + 40 ° С.

The environment is non-explosive, containing no dust in concentrations that reduce generator parameters within unacceptable limits. The vacuum content in the equipment room of the power plant shall not exceed 0.1 mg/m3.

The average service life of the generator is 30 years, subject to the terms and volumes of scheduled inspections and repairs .

The generator is a three-phase implicit electric machine. It consists of a fixed part (stator), which includes a core and a winding connected to an external network, and a rotating part (rotor), on which there is an excitation winding powered by rectified current.

Mechanical energy transmitted from the turbine shaft to the generator rotor shaft is converted into electric energy by electromagnetic means: magnetic flux is excited in the rotor winding under the influence of electric current, under the influence of which electromotive force and electric current are induced in the stator winding.

Losses in rotor and stator windings, in magnetic conductors (stator core, in rotor shaft), as well as mechanical losses from rotor friction in gas medium (ventilation losses) and friction in bearings and shaft seals, are discharged by distilled water (from stator winding), hydrogen (from rotor winding and shaft, from stator core), oil (from bearings and shaft seals).

The generator design is closed sealed.

Distillate in stator winding circulates under pump head and is cooled by heat exchangers located outside generator.

Cooling hydrogen circulates in the generator under the action of fans installed on the rotor shaft and is cooled by gas coolers built into the generator housing

Service water circulation in gas coolers and heat exchangers is carried out by pumps located outside the generator.

Oil supply of generator support bearings and generator shaft exciter and seals is performed from turbine oil system.

Excitation of the generator is carried out from a brushless exciter connected to the generator shaft and consisting of a three-phase synchronous generator of reverse design with a current frequency of 150 Hz. AC rectification is performed by means of a set of rotating semiconductor rectifiers.

General view of generator with exciter is presented on the third sheet of graphic part of A1 format.

1.6.1. Technical specifications

Generator TBB10004 U3 type.

Rated power - 111100 kVA.

Active power - 1,000,000 kW.

The power factor is 0.9.

Stator voltage rating - 24 kV.

Stator rated current is 26730 A.

Rotation speed - 1500 rpm.

The efficiency is 98.7%.

The longitudinal ultra-transient inductive resistance for a positive phase sequence (X "d) is 31.8%.

The longitudinal transient inductive resistance for the positive phase sequence (X'd) is 45.1%.

Longitudinal synchronous inductive resistance (Xd) - 235%.

The inductive resistance of the reverse sequence (X2) is 38.8%.

The inductive resistance of the zero sequence (X0) is 15.8%.

The time constant of the excitation winding at the three-phase K.Z. of the stator winding (T 'd3) is 9.2 s.

Excitation winding time constant at stator open winding (Td0) is 1.8 s.

The time constant of the excitation winding at the two-phase K.Z. of the stator winding (T'd2) is 2.8 s.

Excitation winding time constant at single-phase K.Z. stator winding (T 'd1) is 3.2 s.

The time constant of the periodic component of the super-transient current at one-, two- and three-phase K.Z. (T "d) is 0.022 s.

The time constant of the aperiodic component at three-phase K.Z. (Ta3) is 0.33 s.

Time constant of aperiodic component at single-phase K.Z. (Ta1) - 0.27 s.

Isolation of generator stator winding - class B, on thermosetting binders, rotor - class B.

Insulation of stator winding - 75 0С.

Insulation of rotor winding - 115 0С.

Active stator steel - 105 0С.

Hot gas in the stator housing - 75 0С.

The system of excitement of the generator besshchetochny, diode SBD47070002MUHL4 type with the BVD46001500AUZ activator.

To reserve the main exciter, one spare exciter is provided per power station, similar to the main one.

Rated power - 3300 kW.

Rated current - 7020 A.

Rotation speed - 1500 rpm.

Multiplicity of forcing by current - 2 o.e.

Multiplicity of forcing by voltage - 2 o.e.

Permitted duration of forcing is 15 sec.

1.6.2. Structural units of TVV-1000 generator

The stator consists of the following parts:

housing;

a core;

winding.

The stator is closed from the ends by external shields.

The stator is installed on the foundation by means of flaps, which are removed during transportation. Before the generator is installed on the foundation, the stator is placed on the transport legs, which are welded at the bottom of the stator housing.

Gas-tight stator housing is made of three parts: central and two end parts. Central part containing stator core is integral and has transverse stiffening rings and partitions providing appropriate direction of gas flows. End parts with built-in vertical gas coolers have horizontal connector for ease of transportation and installation.

In order to penetrate the housing without disassembling the external shields, hatches are provided in each part of the housing.

External stator shields are directly connected with internal shields, to which fan shields are connected, consisting of six parts. All parts of the fan boards are isolated from the internal boards and among themselves.

Connectors of external boards are located in horizontal plane. In the outer shields and in the end parts there are special channels through which cooling gas enters the front parts of the rotor winding.

Gas density of connections of stator housing and external shields is provided by a square rubber cord glued along the bottom of grooves cut out in the parting planes of parts of the housing and external shields. Inner shields are sealed with round rubber cord relative to stator housing.

The mechanical strength of the stator housing and the outer panels is sufficient to withstand the internal pressure in the event of an explosion of gases inside the stator at an initial pressure not exceeding atmospheric pressure by more than 0.150.2 MPa, for which purpose the stator housing and panels during their manufacture are subjected to a hydraulic pressure test of 0.8 MPa for 15 minutes.

Stator core is assembled on ribs from segments of electrical steel with thickness of 0.5 mm and is divided along axis by ventilation channels into packages. Surface of segments is covered with insulating varnish.

Ribs of stator core are welded to transverse rings of housing.

Pressed stator core is tightened from ends by pressure rings made of non-magnetic steel. The tooth zone of the core extreme packages is sealed with pressure fingers made of non-magnetic steel, refer to Figure 1.2.

To dampen scattering flows, copper screens and magnetic shunts are installed under pressure rings, consisting of two packages assembled from electrical steel. The shunt packs, and the outermost core packs are pre-glued and baked prior to assembly in the housing to ensure rigidity and monolithic design of the core. Teeth of extreme packs of core and shunts are made with deep radial splines.

Electrical part

2.1. Relay protection of TVV-1000 generator

During operation of generators, their damage and non-normal modes are inevitable. The most dangerous are short circuits, damage to insulation and overload.

Short circuits occur due to breakdown or overlap of insulation, wire breaks, erroneous actions of personnel and other reasons. In most cases, an electric arc occurs at the SC site, the thermal action of which leads to the destruction of the current-carrying parts, insulators. In short circuit, large currents (short circuit currents), measured in thousands of amperes, approach the damage site, which overheat intact current-carrying parts and can cause additional damage, that is, the development of an accident. At the same time, in the network electrically connected to the damage site, a deep decrease in voltage occurs, which can lead to disruption of the parallel operation of the generators.

Usually, the development of accidents can be prevented by the rapid disconnection of a damaged area of ​ ​ the electrical installation using special automatic devices acting to turn off the switches, and called relay protection.

When the switches of the damaged element are switched off, the electric arc in the place of short circuit goes OFF. short circuit current is cut off and normal voltage is restored on undamaged part of electrical installation or mains. Due to this, damage to the equipment on which the short circuit occurred is minimized, or even completely prevented, and normal operation of the undamaged equipment is restored.

Thus, the purpose of relay protection is to detect the location of the short circuit and quickly automatically disconnect the switches of the damaged equipment or network section from the rest of the undamaged part of the generator or network. Also, the purpose of relay protection is to detect violations of normal operating conditions of the equipment, which can lead to an accident, and provide warning signals to maintenance personnel, or disconnect the equipment with time delay.

The relay protection requirements are as follows:

speed;

selectivity;

sensitivity;

reliability.

According to the PUE Paragraph 3.2.34, for turbogenerators it is higher than 1 kV with power more than 1 MW, working directly for combined tires of generating tension (the drawing 14020465.Z13.291.07.00.EZ), devices of relay protection against the following types of damages and violations of a normal operating mode have to be provided:

protection against interfacial short circuits with current setpoint of not more than 0.3 In without time delay and action on generator shutdown, time-excitation and turbine unit shutdown;

protection against winding faults with current setpoint of 0.05 In without time delay with action on generator shutdown, excitation and turbine unit shutdown;

100% protection against ground faults of stator winding with actuation delay not more than 0.5 s;

asynchronous mode protection - disconnection with minimum time delay of 1-2 s;

protection against overvoltage of stator winding with voltage setpoint of 1.2 Unom with action without delay of time for generator de-excitation during idling and its initial excitation, as well as for machine disconnection and de-excitation at load currents of the unit transformer from the side of the system less than 0.1 Inom with time setpoint up to 3 s;

protection against overload by the reverse sequence current with action on the signal at I2 = 0.05 Inom with time delay up to 3 s; for generator shutdown with time delay depending on current characteristic according to value I22t = 6;

alarm of symmetrical overload of the stator with a current of more than 10% with a time setpoint of not more than 10 s;

protection against overloads caused by external short circuits with action to disconnect and de-excite the generator;

We are currently experiencing a real technical revolution associated with the transition to a new generation of RZA devices - microprocessor technology.

The main characteristics of microprocessor protections are much higher than those of microelectronic, and even more electromechanical. The transition to a new element base does not change the principles of relay protection and electrical automation, but only expands its functionality, simplifies operation and reduces its cost. It is for these reasons that microprocessor devices very quickly take the place of outdated electromechanical and microelectronic relays.

The main design task is to calculate the relay protections of the TVV10004 turbine generator with the use of modern microprocessor relay protection tools of the domestic manufacturer of the EKRA NPP, a complex of relay protections of the SHE1110M type generator.

2.2. Calculation

2.2.1. Source Data

Block TTs630000/500 transformer (2 transformers):

Rated power - 630 MVA;

Rated voltage - 525/24 kV;

Rated current - 639/15200 A;

Short-circuit voltage - 14%;

Winding connection - Y/Δ-11.

Auxiliary operating transformer - TRDNS-63000/35 (2 transformers):

Rated power - 63/31,531.5 MVA;

Rated voltage - 24/6.36.3 kV;

Rated current - 1515.5/5774 A;

Short-circuit voltage: U v v = 11.5%; Uk nnnn = 20 %;

Connection of the windings Δ/Δ - Δ-0-0.

The following current transformers are used to connect the 24 kV side protection devices:

of TVT35 type with transformation factor of 3000/5 A - integrated into 24 kV terminals of auxiliary transformers (six single-phase TT sets of two for each phase for each transformer);

the TShV24R type with coefficient of transformation 30000/5 A, established from linear conclusions of the generator (thirty three single-phase sets of a TT on eleven on each phase);

of the TVG24P type with a transformation coefficient of 15000/5 A, installed from the side of zero outputs of the generator (six single-phase sets of TT one for each branch);

of TPOL27UZ type with transformation coefficient 2500/5 A, installed on the side of zero leads in connection between two parallel windings of the stator (one TT with two secondary windings).

From linear conclusions of the generator the transformers of current turn on on total current of two branches of windings of the stator of the generator, from zero conclusions - on current of each of parallel branches of a winding of the stator of the generator (the drawing 14020465.Z13.091.06.00.EZ).

Voltage transformers

On the 24 kV side, voltage transformers ZxZNOL.0624UZ, with voltage of windings B, winding connection are connected. One group is connected between the LV winding of the unit transformers and the load switch, the other group - after the load switch, from the side of the generator line leads.

Generator neutral from the side of zero leads is grounded through ZNOL.0624UZ voltage transformer.

Protection system of fuel generator 110004 of she1110m type

The series of microprocessor protections and automatics of the SE1110M type is designed for use as a complex protection system for station equipment of generating plants, as well as for the implementation of control and automation devices. The RPA complex is made in the form of mutually redundant independent sets (systems) of the RPA, for which individual measuring transformers, separate circuits for direct operating current and separate circuits for exposure to external circuits should be provided.

3.1. Purpose of SHE1110M generator protection system

The complex is designed for use as a protection system of a generator of TVV10004UZ type with a capacity of 1000 MW.

The protection system is made in the form of two identical cabinets that reserve each other.

The complex is executed on the basis of the digital protection of the generator realized on the microprocessor principle (14020465.Z13.091.08.00.E5 and 14020465.Z13.091.09.00.E5).

Each complex includes:

Longitudinal differential protection of generator, IΔG;

Protection against asymmetric overloads I2;

Protection against symmetrical overloads, I1;

Generator reverse power protection, Br;

Two-stage backup remote protection against inter-phase damage. Z1<,Z2<;

Protection against asynchronous mode without loss of excitation, Fz;

Protection against ground faults in generator stator winding. UN (Uo);

Device for serviceability monitoring of AC voltage circuits of 24 kV voltage transformer of generator line leads - CIN;

Voltage boost protection, U >;

Generator lateral current protection, IΔ >;

Maximum current measuring element (for current control in generator circuit breaker circuit), PTG;

Measuring body of the maximum current (for automatic equipment of inclusion of ventilation of the current distributor of 24 kV), I01 I>;

Maximum current measuring element (for arrangement of logic diagram of device for elimination of unauthorized generator actuation). I02 I >.

In addition, the cabinet contains power supplies, receiving and output circuits.

3.2. Technical data

Rated DC voltage is 220V, 100V.

Rated AC voltage - 100 V.

Rated alternating current - 5 A.

Power consumed by the protection cabinet via DC on-line circuits:

In normal mode - 60 W;

In actuation mode - 100V.

Power consumed by the protection cabinet when the rated current and voltage values are supplied to it:

In current circuits - 5VA per phase;

In voltage circuits - 3 VA per phase.

The cabinet has inputs from the following external devices (receiving circuits):

from excitation system protections;

ON position of generator circuit breaker:

from assembly of generator switch contacts:

against process protections;

from assembly of disconnector contacts unit in generator circuit;

reserve;

from contact of switch control command locking relay;

from the current monitoring relay on the 500 kV side;

from contact of switch operating current monitoring relay;

eight backup circuits.

Action from external devices is performed with the help of one isolated closing contact.

It is possible to block the action of receiving circuits using the keyboard of the processor unit.

Output circuits (with the corresponding number of isolated contacts):

disconnection of 01 500 kV switch (main electromagnet) (2 contacts);

disconnection of 01 500 kV switch (standby electromagnet) (2 contacts);

disconnection of 02 500 kV switch (main electromagnet) (2 contacts);

disconnection of 02 500 kV switch (standby electromagnet) (2 contacts);

to ECU circuit 01 and 02 500 k8 (2 contacts);

division of 500 kV busbars (2 contacts);

disconnection of switch in generator circuit (2 contacts);

to inhibit TAPV of 02 500 kV switch (2 contacts);

action of 24 kV ECU (2 contacts);

disconnection of 6.3 kV switch (2 contacts);

reserve (M9) (2 contacts);

to extinguish the field of the exciter (1 contact);

to relay forcing unit (1 contact);

for turbine unloading by active power (ACSAT) (1 contact);

turbine shutdown (1 contact);

start of external oscilloscope (1 contact);

reverse power relay (2 contacts);

turbine idling (1 contact);

two standby circuits (1 contact each);

protection against excitement loss three-phase, F <(Zf.) (1 contact);

protection against asynchronous mode without loss of excitation 2 stage (1 contact);

actuation of current conductors ventilation (2 contacts n.o. and 2 contacts AD).

Circuits supplied to input of digital recorder (without fixation) of "AURA" type with one isolated contact for each of circuits with common point:

longitudinal differential protection of the generator;

protection against asymmetric overloads;

protection against symmetrical overloads;

protection of generator reverse power;

technological protection;

transverse differential protection of the generator;

LNVG device action;

suppression of generator field;

protection against asynchronous mode without loss of excitation 1 stage;

protection against asynchronous mode without loss of excitation of stage 2;

first stage of remote protection;

the second stage of remote protection;

protection against loss of excitation;

protection against voltage rise;

launch of UROV.

In each of the protection systems there is an alarm with action on the annunciator of the central control panel (MCC) with one isolated contact for each of the following circuits:

actuation of protections (with fixation);

current overload I2;

process protection.

In each of the protection systems there is an alarm with action on the MCR annunciator (24 V voltage) with one isolated contact for each of the following circuits:

cabinet failure/output (fixed);

warning fault (call to cabinet) (fixed);

failure of external circuits;

actuation of protections (with fixation);

current overload I;

overcurrent AND;

actuation of ground fault protection in generator stator winding;

reserve;

no operating current.

Signalling (with fixation) on LED indicators with storage of information at disappearance (landing) of live DC power supply voltage and with its subsequent restoration at appearance of power supply voltage.

Said signalling is provided when receiving the following signals:

from excitation system protections;

elimination of unauthorized generator actuation;

from process protections (generator switch is ON);

nine standby circuits; in case of protection action;

longitudinal differential protection of generator, IΔG:

phase A;

phase B;

phase C;

protection against asymmetric overloads, I2:

disconnection;

disconnection (Δt) (1 stage);

disconnection (Δt) (2 stage);

current cutoff element (Δt) (1 stage);

current cutoff element (Δt) (2 stage);

protection against symmetrical overloads:

disconnection (Δt) (1 stage);

disconnection (Δt) (2 stage);

remote protection against short circuit, Z1 <:

disconnection (Δt) (1 stage);

disconnection (Δt) (2 stage);

remote protection against short circuit, Z2 <:

disconnection (Δt) (1 stage);

disconnection (Δt) (2 stage);

shutdown (Δt) protection against excitement loss, F <;

shutdown (Δt) protection against excitement loss, three-phase, F <(Zf.);

protection against ground faults in generator stator winding. UN(U0):

disconnection (Δt) of organ U03;

actuation ( Δt) of organ U0 G;

asynchronous mode protection. Fz:

1 stage (Δt);

2 stage (Δt);

protection against generator voltage increase. U >:

output 1;

output 2;

actuation of transverse current protection of generator, I Δ >;

Generator ECU, RP G at action on output circuits:

disconnection of Q1 500kV switch;

disconnection of Q2 500kV switch;

in scheme UR0V Q1 and Q2 500 kV;

for division of 500kV busbars;

disconnection of switch in generator circuit;

to ban TAPV of Q2 500kV switch;

action of 24 kV ECU:

disconnection of 6.3 kV switch;

reserve (M9);

to extinguish the field of the exciter;

to relay forcing unit;

for turbine unloading by active power (ACSAT);

turbine shutdown;

start of external oscilloscope.

The alarm on the LEDs is cleared using the Reset button on the cabinet door.

3.3. Structure and operating principle of SHE1110M-067 system

The complex consists of two cases (ShE1110M067).

The cabinet is powered through the converter power supply unit from the 220 V battery with permissible deviations of + 10 and minus 20%. The functional diagram of the cabinet is given in the A1 format sheets of the graphic part.

In the diagram, you can distinguish the following functional groups:

single protections (and relays) included in the cabinet, each of which has its own serial number and abbreviated name. The protections (and relays) are made in the form of software functions and have one or more outputs numbered within the protection:

device for blocking protection functions with simultaneous alarm of protection I/O in ES2112 unit;

receiving circuits made on the basis of units ED2164 and EI2071 and having optronic isolation (E11... E1 22) and LED indication of operation;

logic of single protection outputs to output and alarm circuits on DX and DW elements numbered within protection, and DT1... DT34 elements;

Fixed signalling elements (S) (ES2111 and EO2250 units);

elements of recorder (tracking alarm) (R) (EO2250 units);

matrix of action on output circuits, which performs the possibility of action of any of logic signals I 1... I 104 on outputs M1... M14 and is programmable using the keyboard in unit L2425;

output signal amplifiers (EO2250 units);

cabinet operation mode control circuit including mode switch SA1, DX element, output relay "Fault/Output (K17 in A2E2 unit) and two buttons (" Alarm removal "and" Indication call ").

All external chains of a case (chains of the alarm system, chain of the registrar, output chains) connect to a klemmnik of a case via test connectors (XS1 (XB1)... HSZ (HVZ) - for output chains and the alarm system, XSR1 (XBR1) - for chains of the registrar, the specified chains allowing to disconnect quickly and to connect external control units and diagnostics. The loss of contact in any of the test connectors in the output circuits is detected by a special circuit and causes the relay "Output" (CU) to return and the lamp "Fault/Output" to glow on the cabinet door. Loss of contact in test connectors installed in recorder circuits causes disappearance of "Recorder in operation" signal.

The complex has two modes of operation: "Operation and" Output. "

In Operation mode "SA1 selector switch" Operation mode "is in" Operation "position and voltage (Uv) is supplied to output relays of cabinet. Operation of any logical signal specified in the table of entrances of a case (14020465.Z13.091.08.00.E5) and also any exit of a matrix of exits (M) can be given for any light-emitting diode in ES2111 and EO2250 blocks. At the same time, for each LED, you can select the indication mode with or without fixation. This is achieved by means of "alarm matrices" which are programmed by means of a keyboard in unit L2425.

In the Conclusion mode the switch of SA1 "Operating mode" is in the provision "Conclusion" and from output relays of a case stress (Uvykh) is removed owing to what the output Malfunction/conclusion relay (K17 in the A2E2 block), is in not worked state and through it the contact which is not closed (N-z) moves in the external alarm system a signal "A case malfunction/conclusion", and on a door of a case the lamp "Malfunction/conclusion" shines. In this mode, it is possible to test the units and logic of the cabinet, as well as check the actuation setpoints and time delay of the protections.

List of literature

Chernobrovov N.V., Semenov V.A. Relay protection of energy systems - Chapter § 17. Protection of generators.

V.N. Vavin. Relay protection of turbine generator-transformer units. Moscow Energoizdat, 1982

Rozhkova L.D., Kozulin V.S. Electrical equipment of stations and substations. Energoatomizdat, Moscow, 1987

I.R. Taubes. Relay protection of powerful turbine generators. Moscow Energoizdat 1981

Yakubenko I.A., Pinchuk M.E. Technological processes of thermal and electrical energy production at nuclear power plants. Novocherkassk, 2009

Ivanov V.A. NPP operation. Energoatomizdat, 1994

Bublisa I.A. Methodological instructions for the implementation of the section "life safety" in the diploma project of technical specialties. Novocherkassk, 2002g.20s.

SanPiN 2.2.2/2.4.134003 "Sanitary and epidemiological rules and standards." 2003 of 28 pages.

PPB 0103 Fire Safety Regulations in the Russian Federation. 2003. 42 pages.

Kruglova E.Yu., Tabakaeva E.N. Methodological instructions for the implementation of the section on economics on the topic "Planning design preparation of production" in the diploma project. Novocherkassk 2002 59 pages.