• RU
  • icon Waiting For Moderation: 0
Menu

RT717F3

  • Added: 09.03.2017
  • Size: 173 KB
  • Downloads: 0
Find out how to download this material

Description

The circuit diagram of the CNC machine is powered by a flip-flop of the RS type, the flow of information is transmitted through a flip-flop to a thyristor converter, which has a circuit for connecting thyristors with a star, the thyristor converter consists of two parts of two modular units that provide reversal of the DC motor. The first unit of the tryristor converter provides actuation of the DPT (DC) independent drive of forward rotation. The second unit of the tyristor converter enables actuation of the DPT (DC motor) of the independent backward rotation excitation. The main drive of the longitudinal feeds operates synchronously with the rotation of the main motion motor due to the arithmetic logic device (ALU), the signals of which are transmitted to the first thyristor unit (VS 1). In addition, in the graphical part of my course design, the functional diagram of the electric drive of the machine was shown, which consists of the following functional blocks. The functional diagram of the electric drive of the main drive of the KEMTOR type is provided using power supply from the switchgear (RP) of the shop power system of the three-phase AC circuit 380 V. Further, through reactors LR1, LR2, LR3, current transformers TA1 are supplied to phase a, TA2 to phase b through the first block of the valve manifold, where the valve rectifiers are connected by a star, partial rectification of AC to DC is provided and ensures engine rotation forward. The second valve manifold with diodes VD 07... VD12 provides an independent excitation DPT reversal, the independent excitation winding behind is powered by a 380 V AC voltage transformer, where the diode rectifier valve block converts AC to DC. A current sensor is connected to the excitation winding of the DPT, which gives information on the actual current value in the winding of the DC motor, and a DC tachogenerator is connected to the armature winding of the DPT, which gives information on the actual rotation speed of the electric motor in this circuit. In this functional circuit, the information flows to which the SR (control program) directly enters are also reflected, and this circuit has feedback on the position of the switch, which through the inductive converter L, which changes directly the current signals to the power supply of the DPT through the valve converter. In addition, there are several different types of feedback in the circuit that take into account non-linear characteristics and disturbances in the PTA control system; that is, the presence of non-linear links in the engine itself and the tracking system eliminates disturbing factors and signals that lead the DPT ACS out of a stable state. As a result, this functional diagram reflects that in the electric drive of the main movement KEMTOR there are several feedback loops providing reliability of its operation, even under the conditions of interference. In addition to this explanatory note of the course design, I analyzed the varieties of electric drives for CNC machines in the 3 part of the project, where their different characteristics were given, taking into account the operating conditions and advantages for various control schemes. The research part of the course design gave a brief description, purpose and technical characteristics of the CNC machine of model PT717F3. In addition, a description was made of two schemes of this machine, about which I spoke and showed in the graphic part. In addition, in the 4 part, taking into account the individual task for the course design, I compiled and calculated the algorithmic scheme of the automatic control system of the electric drive of the machine in open form (shown on the graphic part) in the absence of external disturbing factors in closed form with the presence of feedback, the purpose of which is to ensure stability of the operation of the electric drive of the machine, even under the conditions of disturbance factors.Stability analysis is carried out in accordance with the law of automation where a complex AU (automatic device) is decomposed (divided) into characteristic typical dynamic links, each of which is described by an integral differential equation taking into account the duration of the transition process coefficient. When compiling an traditimic scheme in the research part, a test was made for the stability of the SAR of the EP machine (automatic control system of the electric drive of the machine) through the Hurwitz algebraic method. In the special part of the CP (5 part), I considered and described in detail the KEMTOR electric drive.

Project's Content

icon 4-chertezha.grb
up Up