SU1635864A1 - Rectifier drive - Google Patents

Abstract

The invention relates to electrical engineering and can be used in a controlled design with valve motors. The aim of the invention is to improve the reliability and accuracy of the drive. In a valve-driven electric drive, the three primary windings of the transformer are included in the anode circuit of the cathode group diodes of the uncontrolled reverse current rectifier, and a fourth winding is included in the DC power circuit. In any mode, the motor current flows in one direction through one of the primary windings of the current sensor transformer, which ensures the formation of a signal at the output of the current sensor. The generation availability control node generates a signal of a logical unit about generation failure, which provides signaling and exclusion of emergency situations. 1 hp f-ly, 4 ill. (Ls

Description

The invention relates to electrical engineering and can be used in adjustable electric drives with valve electric motors.

The aim of the invention is to improve the reliability and accuracy of the drive.

Fig. 1 shows a structural-functional diagram of a valve electric drive: Fig. 2 is a schematic diagram of a three-phase transistor bridge frequency converter with a bridge uncontrolled rectifier of reverse current; FIG. 3 shows the municipal circuit of a generator-measuring transducer unipolar current sensor; Fig. 4 is an example of competitive execution of the generation presence control node.

The valve actuator contains a three-phase synchronous electric motor Nfig.1), the root winding of which is connected to the outputs of a three-phase transistor bridge converter 2 frequencies with a bridge uncontrolled reverse current rectifier, composed of diodes of the anode and cathode groups, the inputs connected to the power source, control unit 3 with control and regulation inputs, with information inputs and outputs for connection respectively to the outputs of the rotor position sensor of the electric motor and control the three-phase transistor bridge frequency converter, self-oscillating measuring-converting single-pole current-sensing sensor 4 equipped with a transformer 5.

Uncontrolled reverse current rectifier is made on. diodes 6-11 (figure 2), in the frequency converter - transistors 12-17. The inputs of the transistor switches 12-47

about

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connected to the outputs of the control unit 3.

A self-generating unipolar current sensor L, mounted on a transformer 5. Equipped with a driver 18 (FIG. 3) for current. The secondary windings 19. 20 of the transformer 5 are connected to the input of the current-forming device 18 of the current signal, the output of which is the output of the self-oscillating one-polar current sensor 4. Three primary windings 21, 22, 23 of the transformer 5 are connected between the anodes of the diodes 6, 7, 8 of the cathode group and the cathodes of the diodes 9, 10, 11 of the anode group of the uncontrolled reverse current rectifier. A fourth winding 24 of the transformer 5 is connected in opposite between the combined emitters of the transistor switches 15, 16, 17 and the combined anodes of the diodes 9, 10, 11.

A node 25 is additionally introduced into the electric drive (Fig. 1. 4) controlling the generation of an auto-generator unipolar current sensor 4, which contains a capacitor 26, one output of which is the input of node 25, a second output connected to resistor 27 and anode diode 28. Second output resistor 27 is connected to the common wire of node 25, and the cathode of diode 28 is connected to the first terminals of resistors 29. 30 and to one terminal of capacitor 31. The other terminal of capacitor 31 and the second terminal of resistor 29 are connected to the common wire of node 25, and the second terminal of resistor 30 is connected to base transist 32. The emitter of the transistor 32 is connected to the common wire of the node and its colloctor is connected to the resistor 33 and is the output of the node 25. The second terminal of the resistor 33 is connected to the power supply.

The valve actuator operates as follows.

In the presence of control commands from the control unit 3, the corresponding keys are turned on and the currents of the synchronous motor 1 are switched.

The following modes are possible:

-the flow of current from the power source through one of the open tank transistor keys of the upper group, for example, 12. and one of the open transistor switches of the lower group, for example, 17;

- current flow under the action of EMF of self-induction or under the action of anti-EMF of the motor along a circuit formed by one of the open transistor switches and diodes (12 and 6 or diodes 16. 11);

-the flow of current under the action of the EMF of self-induction of the engine to the power source through. Idin MJ diodes, for example 6, and one of the diodes, for example 11.

In any of the described modes, due to the inclusion of the three primary windings of the transformer 5 of the autogenerating unipolar current sensor 4 between the anodes

diodes 6, 7, 8 of the cathode group of the reverse current rectifier and cathodes of diodes 9, 10, 11 of the anode group, the fourth winding 24 connected oppositely between the combined emitters of three transistor switches

0 frequency converter 15, 16. 17 and anodes of diodes 9, 1C, 11 of an uncontrolled reverse current rectifier connected to the negative terminal of the power source, one of the primary windings of the transformer 5 of the formatter 5 flows through one the output of sensor 4 of a single-signal current proportional to the motor current.

0 Node 25 of the control of the presence of generation of an auto-oscillating measuring-converting unipolar current sensor works as follows. The voltage in the presence of generation is fed to the input.

5 of node 25, which is a differential link from capacitor 31 and resistor 29.

Differentiating element and diode 30 form positive pulses with constant duration. These pulses are fed to an integrating element consisting of a capacitor 31 and a resistor 29, and the voltage received after integration through the resistor 30 is fed to

5, the base of the transistor 32, wherein the transistor is open and the voltage across the collector of the transistor 32 is equal to the saturation voltage and is close to zero in magnitude.

When generation is disrupted, the output voltage of the unipolar current sensor 4 is zero, the differential link prevents the constant component voltage from passing, and the voltage at the base of transistor 32 is equal to zero, and at the collector of this transistor is equal to the power supply voltage.

Thus, when the generation of the auto-generator sensor is disrupted, the node 25 provides at the monitoring input of the unit 3

0 control logic command about the breakdown of generation, which ensures the elimination of emergency situations that are possible when the negative current connection is broken. Thereby, an increase in the reliability and accuracy of the drive operation is achieved.

Claims (2)

Claim 1. Valve actuator comprising a synchronous motor with a rotor position sensor on a shaft, the root winding of which is connected to the outputs of a three-phase transistor bridge of the frequency converter with an uncontrolled reverse current rectifier formed from diodes of the anode HI cathode group, output connected to a power source No, a control unit with monitoring and regulating inputs, the information inputs of which are connected to the outputs of the rotor position sensor, and the outputs are connected to the control a three-phase transistor bridge frequency converter, and a single-field aptogenerator current sensor, made in the form of a transformer with a primary winding for switching a current measurement into the circuit and a secondary winding connected to the current signal generator input, the output of which serves as an auto-oscillator output -conversion monofield current sensor and is connected to the regulating input of the control unit, characterized in that, in order to increase reliability and increase the accuracy of electric drive transformer autogenerating The measuring and converting unipolar current sensor is additionally equipped with three primary windings, while the primary winding is connected to the DC circuit between the combined anodes of the anode group of the unregulated reverse current rectifier and the combined emitters of the transistors of the three-phase transistor bridge frequency converter, and three additional primary windings, respectively, are included in the AC circuit between the anodes of the cathode and the cathodes of the anodic groups of diodes uncontrolled rectifier reverse current, wherein the cathodes of the anode group an uncontrolled rectifier reverse current are connected to corresponding outputs of the transistor bridge inverter. 2. Electric drive according to claim 1, that is, with the fact that a control unit is additionally inserted into it, which is connected by an input to the output of an apgenerator single-pole current sensor, and by an output to the control input of a control unit . 1 F N five tn o Cfe Cb Cto MS 6j sa -h t 98 (JC9l ITS Fig.Z