SU1434460A1 - Device for simulating loads at engine shaft - Google Patents

Abstract

The invention relates to a technique for testing and physical modeling of automatic control systems for electric drives, in particular, is intended to reproduce the load on the shaft of a traction motor according to the required law. The purpose of the invention is to increase the accuracy in reproducing the characteristics of the engine under test. For this, the device contains a key, a threshold unit and a load current transducer. The device provides the minimum dynamic error in working out a given load on the shaft of the engine under test during periods of its engagement in thrust or electric braking modes, which improves the accuracy of reproduction of the boxing and skidding processes. 2 Il. G w

Description

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The invention relates to the field of testing and physical modeling of automatic control systems for electric drives, in particular, is intended to reproduce the load on the shaft of the traction motor according to the required law.

The purpose of the invention is to improve the accuracy of reproduction of the characteristics of the engine under test.

Figure 1 presents the block diagram of the proposed device; 2 - the same, with the decoding of individual blocks to the level of known functional elements.

The device for modeling loads on the motor shaft contains the motor 1 under test, which is connected to the shaft of the generator of direct current 2 independent excitation, the core of which is connected to the output of controlled converter 4 connected by inputs of control unit 5 via current sensor 3. The first input 6 of the control unit 5 is connected to the output of current sensor 3, and the second input 7 via the switch 8 is connected to the output of the unit 9 for setting the torque. The control input of the key 8 is connected to the output of the threshold unit 10, the input of which is connected to the output of the converter 11 of the load current of the motor under test 1. The controlled converter 4 is connected to the AC mains 12 (for example, three-phase with zero output).

Figure 2 shows an example of the execution of the circuit of the threshold unit 10, the circuit of the key 8 and its connection to the input of the current controller on the operational amplifier of the control unit 5 and to the output of the unit 9 of the torque command. The key is; on the field-effect transistors 13, the current controller of the control unit 5 and the threshold unit 10 are operational: amplifiers 14, 15. In addition, unit 5 includes resistors 16, capacitor 17 Block 10 includes a potentiometer 18, resistors 19. Converter P includes resistor 20, rectifying bridge 21 and coil, 22 inductors. Key 8 also includes a resistor 23.

The device works as follows.

When an electromagnetic moment (motor or braking) of the motor under test 1 occurs, the output signal of the current converter II, other than zero, appears, at which the output of the threshold unit 10 is jumped by the voltage signal of the closing switch 8 and input 7 the control unit | 5 from the output of the moment setting unit 9 receives a voltage signal proportional to the set torque (in the absence of the electromagnetic moment of the subject. motor 8, the key is open and the voltage signal at input 7 is zero), which The generator excitation magnetic flux of generator 2 is also proportional to the current measured by the sensor 3 currents in the circuit: controlled converter 4 is the generator measurine with a constant time of this circuit sets the amount of current (specified moment) with minimum dynamic error. In this case, with a counter load (start mode), the control converter 4 will work with energy output to the network 12, and with the associated load (for example, when the tested engine is in electric braking mode), it consumes the necessary energy from the network. The power circuit of the controlled converter 4 and its control unit 5 can be performed according to the scheme of the reverse controlled voltage of the mitters receiving power from the three-phase network. The pulse-phase control system (SIFU) included in the control unit is fulfilled, for example, according to the vertical control principle, and has an inverse dependence of the unlocking angle on the input signal, thereby obtaining a direct dependence of the actual voltage of the rectifier on the input signal. The input signal to the SIFU comes from the current regulator, which is also included in the control unit (not shown in Fig. 2) and also included according to the unified block system of regulators UBSR or the regulator circuit, for example, the proportional-integral regulator on the operational amplifier .

Claims (1)

Invention Formula A device for simulating loads on an engine shaft, comprising a motor under test, a direct current generator, independent excitation, a current sensor, a controlled voltage converter, a control unit and a torque command unit, the motor under test is mechanically connected to a single excitation DC generator core The core of the winding of the core of which is through the current sensor, and the other end of the winding of the core of the DC generator of independent excitation is directly connected to the outputs of the controlled terminal a voltage converter connected to a three-phase AC network, the control inputs of which are connected to the corresponding outputs of the control unit, the first information input e434460 which is connected to the output of the current sensor, characterized in that, in order to improve the reproducibility of the characteristics of the motor under test, it contains a key, a threshold unit and a load current transducer connected to the power supply circuit of the motor under test. ten 15 I-. the output of the time reference block is connected with the information input of the key, the output of which is connected to the second information input of the control unit, the control input of the key is connected to the output of the threshold unit, the input of which is connected to the output of the load current transducer of the motor under test. . .Z