SU944064A1 - Device for control of group of single-phase current inverter - Google Patents

Description

one

The invention relates to electrical engineering and is intended to control a valve converter for transmitting energy from an MHD generator to an industrial network with a higher frequency link.

A device for controlling an inverter current is known, consisting of a master oscillator (multivibrator), a logic distributor (converter) and driver control formers, it is unsuitable for controlling a group of inverters, each of which is connected to a corresponding 5-frame MHD- generator.

The closest in technical essence to the invention is a phase control device operating according to a vertical principle, which provides high dynamic properties of a control device. The device consists of a source of reference voltage (in autonomous

the converters are built on the basis of a multivibrator connected to a generator of linearly varying voltage), a source of voltage control connected via an adder to a comparator, an output voltage sensor, a second adder, an integrator with a cumulative element, a bridged key connected to the control circuit of the key C23.

However, the known device is intended to control the output parameter of the converter converter. In the system under consideration, the input parameter is required to be adjusted — the no.) Equalization of input currents; the output parameter adjustment is placed on the device to control the direct purity converter.

Claims (2)

The purpose of the invention is to expand the functionality of the device. The goal is achieved by the fact that the device for controlling a group of single-phase current inverters, containing a multivibrator connected via a generator of linearly varying voltage to the first input of the adder with a comparator, and a key, one connected to a cumulative element, is equipped with a single-source, constant source this voltage and two sensors of input currents the output of the generator of linearly varying voltage, the first is also connected to the second input of the adder, sensors of the input currents of the inverters are connected to the third and fourth inputs of the adder, the second input of the comparator is connected to the source of the constant voltage, the outputs of the comparator and the multivibrator are intended to connect to the inverter. The drawing shows a block diagram of the device. Multivibrator 1 through a generator of linearly varying voltage 2, adder 3 and comparator 4 is connected to the input of a single vibrator 5, the output of which is connected to the control circuit of key 6, which connects the output of the generator of linearly varying voltage 2 to the second input of adder 3 , and cumulative element 7- To the third and fourth inputs of the adder 3 sensors of the input VOKOB inverters 8 and 9 are connected. The source of the constant voltage 10 is connected to the second input of the comparator 4. When controlling a set of inverters, each subsequent must have The control channel, constructed similarly to FIG. 1. The principle of operation of the device is as follows. The device provides a shift of the control pulses of the two inverters by the error angle gr, at which the input currents of the inverters are equal. Multivibrator 1 operates at a frequency equal to the ripple frequency of the input voltage of the inverters, i.e. with double frequency. The falling edge of the output voltage of the multivibrator 1 determines the position of the control pulses on the gates of the first ine 4 driver (the output drivers are not shown in the drawing), the leading edge starts the generator of the linearly varying voltage 2. Consider at first the inverter input currents , and the angle of mismatch between them is equal to y. When the voltage is equal to zero at the output of the adder 3, the comparator k is activated and starts the one-shot 5 for the holding time tg. At the end of tg, the back edge of the output voltage of the single vibrator 5 closes the key of the storage element and the value of the linearly varying voltage of the generator 2 is transferred (instantly), after which the key 6 opens and the accumulation element 7 stores the recorded voltage value until the next closure of the key 6 The voltage recorded in the storage element is equal to + and where and is the voltage of the generator 2 at the time of the operation of the comparator C; and Stg, where S is the voltage slope of the generator 2. A constant voltage equal to U is applied to the second input of the comparator due to this, in the established mode, the operation of the comparator occurs at a constant error angle. The control pulses of the second inverter 8 are removed from the output of comparator i. If inequality of the input currents of the inverters occurs, the corresponding voltage increment is applied to the comparator 4 and the angle is changed. The transient continues until the input currents of both inverters are equal. Thus, the invention makes it possible to meet the requirements for the converter supplying from the MHD generator, in particular, to achieve equalization of the input currents of the inverters, which allows to solve the problem of creating valve converters for MHD generators based on converters with a higher frequency link. In such converters, it is effectively solved the problem of the summation of power from the individual frames of the MHD generator, which up to now has not had an effective technical solution. Due to this, it is possible to create converters for MHD generators with high technical and economic indicators. Apparatus of the Invention A device for controlling grouped single-phase current inverters, comprising a multivibrator connected via a linearly varying voltage generator and a first input of the adder with a comparator, and a key, the first one connected to a cumulative element, different from expansion of functional capabilities, it is equipped with a single-vibration, a source of direct voltage and two sensors of input currents of inverters, and you t 6 running the comparator is connected to the input of a single-vibration, the output of which is connected the key's control input, the second output of which is connected to the generator output of a linearly varying voltage, the first output is also connected to the second input of the adder, to the third and fourth inputs of which the sensors of the inverter input currents are connected, the second input of the comparator is connected to the source of the constant voltage, The outputs of the comparator and the multivibrator are designed to be connected to the current inverter. Sources of information taken into account in the examination. Autonomous inverters. Ed. G.V. Chaly. Chisinau, Shtiintsa, 197, p. 292. 2. If copyright certificate. cl. H 02 R 13/18, 1975.