SU942240A1 - Device for pulse-phase control of converter - Google Patents

Description

The invention relates to electronics. namely, power converter technology, and can be used in static converter control systems. A device for pulse-phase control is known, which contains a block of six key elements controlled by a pulse distributor, two comparators and two meters connected to a source of constant voltage. A disadvantage of this device is the low stability of the range of control angles with variations in the value of the supply voltage of the network. Closest to the proposed device is a device containing a multiphase alternating voltage supply voltage, the output of which is connected to three blocks of key elements with a number of key elfts, equal to the number of phases of the converter in each of the blocks, two potentiometers ONeNVH between the outputs of blocks of key eletngov, two comparators, the unit for forming the angle of control of the valves, the converter, the logic elements AND and OR the first inputs of which are connected to the outputs of the comparators pulse former, the output k1he pogo connected to the input of the pulse distributor. A poorly known device is that these angles are influenced by the shape of the supply voltage curve. And since during operation of the converter in the pitakotsey of the network to which it is connected, iQOf3HincaiEöt. distortion, then use Calling a device that, if operated with the limit control, leads to a malfunction of the converter. The purpose of the invention is to increase the accuracy and reliability of the control system of the converter. The goal is achieved by the fact that the device; im Icno-faiz6iaoGbUSch) aiB veninin converter, you are equipped (famv1 "multiphase voltage to

two integragorami each kogorUh provided with block zeroing solder inputs of the rectifier are connected to the outputs of the sensor multiphase voltage and vy4 turn connected to the inputs ingegratorov and tiepBbiM vhodamI comparator inputs ingegratcherov also connected to the engine soogvegsgvuyuschih potentials integrator outputs are connected to second inputs of comparators, the output of the converter control valve forming unit is connected through the OR element to the input element AND, the output of which is connected to the second input of the pulse former, and the output d PFN - to the control inputs of the zeroing block

FIG. I presents the scheme of the proposed device; in fig. 2 is a diagram of its operation, on which output voltage curves are plotted on individual elements of the device, operating in the mode of forming the maximum control angle.

The device contains a multi-phase alternating voltage sensor I (Fig. 1) three blocks of key elements 2-4 with six control keys in each of them, two potentiometers 5 and 6, two comparators 7 and 8, a block 9 of forming the control angle of the converter valves And 10 and II logic elements, 12 pulse generator, 13 pulse distributor, multiphase voltage expander 14, two integrators 15 and 16, zeroing blocks 17 and 18, voltage 19-21 at the output of each block of key elements in a given point in time (Fig. 2), voltage 22 to the output e rectifier, voltage 23 at the potentiometer slider, voltage 24 at the integrator output, pulses 25 at the driver output.

The device works as follows.

Using a multi-phase alternating voltage sensor, a six-phase system of sinusoidal voltages is formed, which is proportional to the phase voltages of the mains supply. The six-phase voltage system is fed to the input of blocks of key elements with six controllable keys in each of them, and the subcontrol of these blocks is such that the phase shift between the input variable voltages of each block is 12 ohl.h. Key management 1 is produced by pulse signals of duration

6O el.grad., Obtained at the output of the pulse distributor. In this case, the phase shift between the control signals of two neighboring keys of the block is 6 O electrical degrees. The control signals to the like keys of each of the three blocks are applied synchronously. As a result, when the device operates at the output of each block of key elements, at the given moment of time one of the phase voltages is connected, and in total they form a three-phase voltage system 19-21, Consequently, the voltage on the slider of the potentiometer

connected between the outputs of two blocks of battery cells, has a phase intermediate between the phases of the voltages of these blocks and changing the position of the slider, continuously regulating this phase of the voltage within 120 al. In other words, by appropriately connecting the potentiometer and moving its slider, the phase of the voltage applied to one of the integrator's inputs can be set to any desired value — diagram 23.

Claims (2)

The input of each integrator receives the difference between the voltage taken from the slider of the corresponding potentiometer and the output voltage of the multiphase voltage rectifier (Fig. 3) - diagram 22. The integrated difference of these voltages goes to the input of the comparator - diagram 24. At time when the integral of the difference between the voltage on the potentiometer slider and the voltage at the output of the transmitter becomes equal to the comparing threshold, the comparator is triggered, a pulse is formed at its output, the instant of time This corresponds to the value of the limiting angle of the control angle of the valve converter. The minimum control angle of the valve converter is formed in the device using a potentiometer 6, integrator 16, compatxjpa 8, the maximum angle using a potentiometer 5, integrator 15, comparator 7. One input of the logic element OR pulsed signals | corresponding to the maximum control angle, on the other - signals from the output of the control angle formation unit. From the output of the element OR, the signal is fed to the input of the logic element AND, to the other input of this element receives pulse signals corresponding to the minimum angle of control. As a result, at the exit. Pogic element And forms; im pulse: the signal, the phase of which corresponds to the angle of control of the transducer, and the name of the speaker are in the process of regulation within the limits of, cc (1ds | CS) And the values are equal to the moments of equality of the outputs at the outputs of the integrators by a threshold, and the position of the potentiometer sliders does not depend on the change in the voltage value of the power supply network. The control pulses of the zeroing unit come from the output of the pulse shaper - diagram 25. These same pulses are the input control with a pulse distributor signal that converts an input single-channel pulse sequence into a six-channel | with a relative phase shift between the channels equal to 60. The output pulse signals of the pulse distributor, are amplified, are fed to the control electrodes of the thyristors of the six-phase converter, using the invention to improve the accuracy of the six-phase converter. operation of the pulse-phase converter control system by increasing the stability of the limiting control angles. The invention The device for pulsed phase control converter, containing a multiphase alternating voltage supply voltage sensor, to the output of which are connected three blocks of key elements with a number of key elements equal to the number of phases of the converter in each of the blocks, two potentiometers connected between the formation outputs the angle of control of converter valves, logic gates AND and OR, the first inputs of which are connected to the outputs xc of the parators, the driver of the pulses, the output of which is connected to in An impulse distributor ode, characterized in that, in order to increase accuracy and reliability, it is equipped with a multiphase voltage rectifier and two integrators, each of the K-Vorps is equipped with a zeroing unit, and the rectifier inputs are connected to the outputs of the multi-phase voltage sensor, and the output is connected. to the inputs of the integrators and the first inputs of the CC 4Parators, the inputs of the integrators are also connected to the sliders of the corresponding potentiometers, the outputs of the integrators are connected to the second inputs of the comparators, the output of the converter control angle forming unit is turned on; through the OR element to the input of the AND element, the output of which is connected to the input of the pulse former, and the output of the pulse former, to the control inputs of zeroing units. Sources and formulations taken into account in the examination 1. Swedish Patent No. 16515/67, cl. H 02P 13/16, 197Y. 2. Authors svipetelsg about the USSR by application; 24O4659 / 24-О7, 9Л. H 02 R 13/16, 1978. tttttt nineteen go L 7 Jxjvjvjvj-vt Z2 but P p p p p p L l V7 /