SU1640805A1 - Device for control of thyratron motor - Google Patents

Abstract

The invention relates to electrical engineering and can be used in controlled drives of automatic control systems. The aim of the invention is to increase reliability. For this, the device for controlling the valve electric motor contains the distributor modulator 2, the output of which is connected to the switch and the input to the controlled reverser, and the driver of the dynamic braking mode. Additionally, the device comprises a reverse delay unit and an emergency braking unit. When the reverse signal is applied to the reverse delay unit 14, at its master output the signal appears with a delay. For the delay time, the distributor-modulator 2 does not generate key management signals. After a delay, the keys are turned on to provide a reverse. At the same time, the keys are protected against through-currents. The emergency braking unit switches the switch key management algorithm to dynamic braking mode, while also providing a switch-on delay for the keys providing protection from through-currents, which increases the reliability of the device. 2 hp f-ly, 3 ill.

Description

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13

information signals of the three-phase sequence from the output of the reverser 1; M is the width-modulated speed control signal; X and X are the output signals of the emergency braking unit 15.

At zero signal level M, all keys 33-35 of the cathode group are locked and the engine is unplugged from the network. In case of trouble-free operation, all the alarm signals At and A are high and the output signals of the node 7

Y l

1, X2 0.

If there is at least one alarm signal, in this case all the keys 36-38 of the anode group are locked and the keys 33-35 of the cathode group are open. Thus, the motor is disconnected from the network, and all its windings through the keys and diodes of the lower group are short-circuited, creating a dynamic braking circuit. Moreover, a high level signal X2 appears at the output of block 15 with a delay relative to the low level signal X. Thus, the keys 33-35 are opened after reliably locking the keys 36-38, which eliminates the possibility of the flow of through currents and increases the reliability of the device.

five

0

five

0

five

a

3

c3 come on

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the inputs of the distributor-modulator 2. As follows from the equations of its logic in conjunction with the shaper 3 dynamic deceleration modes (Fig. 3), the signals of the active high level at each time point are sent to two switch keys of different arms of the bridge. Moreover, one of the keys relates to the anode group, and the other to the cathode one. The duration of the open state of each key is 120 degrees, and the operation of the keys of one arm is divided by an interval corresponding to 60 degrees, which eliminates the possibility of the flow of through currents in the switch arms when switching. The signal M is input simultaneously through the key channels 33-34. In the signal pause M, all keys of this group are locked.

The reversal of the direction of movement is set by changing the logical state of the signal P in this case from 0 to 1. At the same time, the state of the signal P and from 1 to O at the control input of the reverser 1 changes with a time delay, which leads to an inversion at the output of the EXCLUSIVE OR circuit. reverser 1 input information signals. Due to this, a change to the opposite sequence of operation of switch keys occurs, the direction of the current in the phases of the valve motor and its electromagnetic change

moment. This leads to deceleration in opposition mode with subsequent reversal of the direction of movement.

The delay in changing the state of the signal P at the control input of the reverser 1 is introduced to restore the locking properties of the keys. The delay is realized by the chain switching on of three inverters 21-23, separated by integrating RC chains 24 and 25. The presence of two RC circuits ensures the symmetry of the delay time as when the signal P changes from high to low, so from low to high. When the signal P changes at the output of the EXCLUSIVE OR 20 circuit for the duration of the signal passing through the delay chain, a prohibition signal is generated in the form of a low logic level, which enters the inputs of the AND circuits 17-19. In this case, all information signals at the output of block 14 are equal to 1, which, in accordance with the logical equations, removes the control signal from all switches of the switch. (The same will happen if all signals at the output of circuits 17-19 are equal to O, in the absence of inversion at their outputs). The duration of the exposure is determined by the selection of the parameters of the RC circuits and must not be less than the recovery time of the locking properties of the power switches. At the end of the delay time, the state of the signal at the control input of the reverser 1 is changed, and the prohibition signal is released.

Similarly, the device operates in its implementation in accordance with figure 2. Here, the switch key control signals are described by the equations

Y6 a, .b, ..

Thus, in the device in any modes of operation, the possibility of the flow through

currents in the switch arms and ensures that the motor is switched to dynamic braking mode in emergency mode, which increases the reliability of the device.

Claims (3)

1. A device for controlling a valve electric motor containing a controlled reverser, a distributor-modulator composed of two groups of AND circuits, the number of which in rpvnne is three, and three inverto5 POV, the first input of each circuit AND of the first group is combined with the first input of the corresponding circuit And the second group, forming one of the inputs of the distributor-modulator, connected to the corresponding output of the controlled reverser, the second input of each circuit AND the first group is combined with the second input of the corresponding circuit AND the other group and one of vertorov in5 is connected to one of the inputs of the distributor formed by the modulator, circuits, the outputs of the first group and the distributor modulator connected to the control inputs of the key switch group anod0 hydrochloric, and the outputs circuits of the second group of the distributor - modulator through the controlled driver of the dynamic braking mode - to the control inputs of the keys The cathode group of a switchboard equipped with inputs for connecting to a power source and outputs for connecting the core winding of a valve motor, characterized in that, in order to increase reliability, each And distributor-modulator circuit is equipped with a third input and an emergency braking unit with n inputs is inserted for filing. 5 alarm signals and two outputs, a reverse delay block composed of three two-input circuits AND with Schmidt thresholds, an IDEA EXCLUSIVE logic circuit, three inverters and two RC circuits, the first inputs and outputs of the circuits AND with Schmidt thresholds form the information inputs of the reverse delay block respectively for connecting to the sensor position of the rotor of the valve electric motor and the outputs connected to the information inputs of the controlled reverser, the second inputs of the indicated circuits AND the reverse delay unit are connected and connected 0 To the output of the logic circuit EXCLUSIVE OR, the first input of which is combined with the input of the first inverter to form the input of the reverse setting of this block, the output of the first inverter is connected via the first RC circuit to the input of the second inverter connected to the third inverter through the second RC circuit, the output of which is connected to the second input of the EXCLUSIVE OR logic circuit and forms the output of the task of the reverse delay unit connected to the control input of the controlled reverser, the third inputs of the AND distribution circuits of the first group - modulator o edineny and connected to the first output of the emergency brake unit, a second output is connected to the control house vho- shaper dynamic braking mode, and the combined third inputs of AND gates of the second group distributor modulator form a control input of the distributor l -mode torus. 2. The device according to claim 1, characterized in that the emergency braking unit is composed of an AND n-input circuit, a diode, an inverter and a driver. of the RC termination circuit, the resistor of which is shunted by a diode connected in the opposite direction, the inputs of the emergency braking unit are formed by the inputs of the AND circuit, the output of which is connected to the input of the inverter and forms the first output of the emergency braking unit, the output of the inverter is connected to the input of the integrating RC circuit, the output of which is the second output of this block. 3. The device according to claim 1, characterized in that the second group of circuits AND of the distributor-modulator is made with inversion on the output the dynamic braking driver is composed of two-input AND-NES circuits, and the emergency braking unit includes an n-input circuit AND, a diode and an integrating circuit whose resistor is shunted by a diode connected in the forward direction, the inputs of circuit I form the inputs of the emergency braking unit, its output is the first output of the specified block, and the second output is formed by the output of the integrating circuit, the input of which is connected to the output of the circuit I., 0 + four - Fig1 Fig.d