SU404169A1 - DEVICE FOR REGULATING EQUITATIVE CURRENT REVERSIBLE VENTIAL CONVERTER - Google Patents

Description

one

The invention relates to an adjustable electric drive powered by engines from reversible valve converters and can be used in drive control systems in the metallurgical, machine-building, paper-making and other industries.

To ensure the speed of the reversing valve converter when the load current is transferred from one of the valve groups operating in the rectifying mode to another group of valves that must be operated in the inverter mode and vice versa, precise matching of the characteristics of the rectifier and inverter inverter groups is required.

A device for regulating the equalizing current of a reverse power converter is known, containing current regulators of the rectifying and inverter groups and the regulating current regulator. The outputs of the reference node and the load sensor are connected to the inputs of the current regulators, and the output of the reference current node is connected to one of the inputs of the surge current regulator. The sensors of the rectifying currents and and the inverter groups of the converter are connected to the second input of the regulating current regulator.

In the known device, the output of the regulating current regulator is connected to the inputs of the current regulators of the rectifier and inverter groups of the converter, and the outputs of the current regulators to the systems of the phase control of the converter groups.

In such devices, the adjustment of the surge current regulator is made depending on the load current of the converter. With

This makes it almost impossible to adjust the regulators according to optimal criteria, since the parameters of the equalizing circuit and the circuit of the load current of the electric motor are different.

As a result, when the motor current contour is optimally tuned, surge currents may occur, and if the surge current is eliminated, dynamic current is adjusted and the surge current is optimally adjusted, the motor current regulator may not be fast enough.

The purpose of the proposed device is to provide independent configuration of current circuits.

load and balancing current.

This is achieved by the fact that the second input of the regulator of the balancing current through the minimum separation unit is connected to the outputs of the sensors of the balancing current of the rectifier and

inverter inverter groups, and the output

the specified regulator - with the phase control systems of the rectifier and inverter groups of the converter.

The proposed device contains two separate independent current regulators - to regulate the surge current and to regulate the load current.

The drawing shows a block diagram of the proposed device.

An adjustable reversing converter consists of a rectifier 1 and an inverter 2 groups. The voltage on the converter is fed through a transformer 3.

To limit the leveling current, the cathode chokes 4 and 5 are used.

The control of the valves is carried out using phase control systems 6 and 7, to which, through intermediate summing amplifiers 8 and 9, signals from the regulating current regulator 10 and the load current 11 are supplied.

Voltages proportional to the load current and surge current are removed from current sensors 12, 13, 14, which are connected to shunts 15, 16, 17 in the respective power circuits.

The feedback signal of the equalization taku is obtained by separating 1min from the currents, flowing them through the rectifier (shunt 15) and inverter (shunt 16) groups with the help of the node - the current minimization.

The selection of the minimum currents is as follows.

The signals from sensors 12 and 13 of the rectifying current 1 and the inverter 2 groups are compared to each other via DC-biased diodes 18 and 19. The diode bias was performed using a constant voltage source and a resistor. The larger of the output signals of the current sensors 12 and 13, corresponding to the sum of the load currents and surge current, closes its diode (18 or 19) and a signal proportional to the smaller of the two currents, i.e. equalization current, is obtained at the output of the current-minimum discharge node.

At the input of the regulating current regulator 10, the setting of the equalizing current with the feedback signal Åe is equalized to current.

The feedback on the load current from the current sensor 14 goes to the load current terminal 11.

The control system can be implemented on the elements of UBSR.

Thus, a device with two separate controllers allows independent, optimal tuning of each of the current control loops.

Subject invention

A device for regulating the balancing current of the reversing valve converter, containing a current regulator, to whose input the outputs of the reference node and load current sensor are connected, and an equalizing current regulator, to the input of which the output of the differential current reference node is connected, while the output of the current regulator is connected with phase control systems of the rectifier and inverter groups of the converter, characterized in that, in order to ensure independent adjustment of the load current circuits and the surge current, entry

an equalization current regulator through the minimum allocation unit is connected to the outputs of the equalization current sensors of the rectifier and inverter groups of the converter, and the output of the specified regulator is connected to the systems

phase control of the rectifier and inverter groups of the converter.