SU575756A1 - Device for controlling thyristor converter - Google Patents

Description

one

The invention relates to a converter technique and can be used to control a converter consisting of two oscillating inverters and an output reversing rectifier.

A device is known whose output voltage is formed by reversing the rectification of two sinusoidal high-frequency voltages with equal amplitudes and close frequencies. The balance of this device is low efficiency.

The closest in technical essence to the invention is a device 12} for controlling a converter, which contains two high-frequency channels, one of which consists of a series-connected reference oscillator, a frequency divider, a driver for controlling the pulses of the first inverter, and the other of series-connected oscillator. , the synchronization unit of the OR element, the frequency divider, the control pulse generator of the second inverter, as well as the channel for allocating the difference frequency, which and it and the sequentially connected element I, the trigger and the driver of the control pulses of the reverse rectifier.

The disadvantage of this device is that a periodic change in phase shifts between pulses of high-frequency channels: causes additional circulation of reactive currents in the converter, which is reflected in its efficiency and weight dimensions.

The purpose of the invention is to increase the efficiency of the converter.

Claims (1)

The goal is achieved by a device for controlling a thyristor converter on two oscillating inverters with an output reversing rectifier containing a reference oscillator, one of the outputs of which through the first frequency divider is connected with the control pulse driver of the first inverter, an adjustable oscillator connected through a synchronization unit , the logical element OR, and the second frequency divider to the shaper of the control pulses of the second inverter, the logical element AND, whose inputs are connected with the outputs of the frequency dividers, and the output through the trigger is connected to the (Shaper of the control pulses of the reverse rectifier, additionally equipped with the second logic element -and. and the logic element Ban, and the logical element of the Ban is connected between the output of the alternator and the input of the first divider the frequencies, the inputs of the second logic element AND are connected to the outputs of the frequency dividers, and its output is connected to the control input of the logic element Inhibit. The drawing shows a block diagram; The proposed control device The device contains a reference generator 1, an adjustable generator 2, an element of the Inhibit 3, a synchronization unit 4, the element OR 5, d, frequency switches 6 and 7, elements 8 and 9, trigger 10, driver control pulses 11,12, 13. The device operates as follows. The pulses from the unit output of the reference generator 1 through the element Ban 3 arrive at the input of the frequency divider bis output of the latter trigger the driver of the control impulses 11 of the first inverter. The pulses from the zero output of the reference generator 1 and the pulses from the output of the adjustable oscillator 2 are fed to the input of synchronization unit 4. For each impulse of adjustable frequency, the synchronization unit produces a strobe at the output, the fronts of which coincide with the fronts of the reference frequency pulse coming from the zero output of the reference generator. The positive fronts of these gates arrive at the input of the element 5, the second input of which receives pulses from the output of the interdiction element. Thus, the element OR 5 sums two pulse sequences whose fronts are synchronized by pulses of the reference frequency apart and, therefore, do not coincide in time. . When the total pulse sequence is divided by the frequency divider 7, the irregularity of the pulse following period is compensated for with a given accuracy. The output pulses of frequency divider 7 trigger the control pulse generator 13 of the second inverter. The output pulses of the element And 9 are fed to the input of the trigger lO, the output pulses of which trigger the driver of the control pulses 12 of the reversing bridge. The output pulses of the AND 8 element arrive at the control input of the Inhibit 3 element. As a result, the frequency of the pulses fed to the inputs of frequency dividers b and 7 and, respectively, the control thyristor electrodes of both inverters changes during the period of the output frequency of the converter | triangularly (PWM according to a triangular law), the change in the operating frequencies of the inverters occurs synchronously and the output frequency of the converter, defined as the difference between the summed frequencies, does not change when the frequency of the reference generator changes Torah. The frequency modulation of the reference oscillator allows you to adjust the power supplied to the parallel capacitors of the oscillating inverters, which reduces the fraction of reactive energy that is returned to the network. The sinusoidal form of the output voltage of the converter is not disturbed in this case, since the magnitude of the parallel capacitances is determined by the minimum distortions at maximum load. Thus, a slight complication of the control circuits of the converter allows stabilizing the load characteristic of oscillating inverters and increasing the efficiency of the converter. The invention The device for controlling an Iristor converter on two oscillating inverters with an output reversing rectifier, containing a reference oscillator, one of the outputs of which through the first frequency divider is connected with the driver of control pulses of the first inverter, an adjustable oscillator connected through a synchronization unit, a logical element OR , and the second frequency divider to the control pulse driver of the second inverter, the logical element And, the inputs of which are connected to the outputs share frequency, and the output through the trigger is connected to the driver of the control pulses of the reverse rectifier, characterized in that, in order to increase the efficiency of the converter, it is additionally equipped with a second logical element AND and a logical element of the ban, and the logical element of the ban is connected between the output of the reference generator and the input of the first frequency divider, the inputs of the second AND logic gate, are connected to the outputs of the frequency dividers, its output is connected to the control stroke of the Zareth logic element. -. Sources of information taken into account in the examination: 1 „Comp-leb Reudus UebdemaddtK-esdes des Aeahces de fAcadetnie des & eietieea France Seme B, t.2бl, Fev f967r. 2, USSR Author's Certificate 516170, cl. H 02 P 13/16, 1974.