SU1343518A1 - Digital device for controlling thyristors converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used in direct current converters. The aim of the invention is to improve the accuracy of control. By introducing analog-digital converter 5, multiplication unit 13 and comparison unit 11, the device takes into account all changes in the input voltage and averaging is performed in a small period of output voltage measurement, and the converter operation is controlled directly in the control period, which allows for variations supply voltage and load magnitude change. 1 il.

Description

The invention relates to electrical equipment. And can be used to control thyristor pulse-width DC-DC converters.

The aim of the invention is to improve the accuracy of control.

The drawing shows a functional diagram of the proposed device.

1Digital device is designed to control a thyristor converter containing voltage source 1, power thyristor 2, which is connected in series with load 3, and switching node 4. From load 3, voltage goes to the output voltage integrator at the first analog-digital input the Converter 5, the second input of which receives pulses from the generator 6 clock pulses. The pulses of the generator 6 are fed simultaneously to the input of the counter 7. The output of the converter 5 is connected to the input of the adder 8, the output of which is connected to the input of the register 9, the output of which is connected to the input of the register 10, the output of which is connected to the first input of the comparison block 11 and the second input of the adder 8. The enable inputs for writing registers 9 and 10 are connected to the output of generator 6, and the reset inputs of registers 9 and 10 to the second output of counter 7, the first output of which is connected to the control electrode of the thyristor 2. The output of block 11 is connected to the input of node 4, and second input unit 11 - via analog-to-digital preob- - verters 12 and multiplying unit 13 from the source 14 a control signal unit 13 has a control input to which is supplied a binary code whose value is proportional to the period of operation of the transducer.

The device works as follows.

From the output of the generator 6 to the input of the counter 7 receives a sequence of pulses. From the first output of the counter 7, at the beginning of the operation period, a control pulse arrives at the control electrode of the thyristor 2. The sequence of control pulses whose frequency is equal to the frequency of the generator 6 divided by the division ratio of the counter 7 determines the frequency of operation of the thyristor converter. After impulse control

the input voltage of the thyristor 2, the voltage of source 1 is applied through the open thyristor 2 to the load 3. At the same time, the output voltage of the thyristor converter is fed to the input of the converter 5, which converts the voltage to binary code, The frequency of oscillator 6 determines the conversion period of converter 5, which converts the input analog signal to a digital code in one clock cycle. Thus, the measurement frequency of the output voltage coincides with the frequency of the generator 6. With a large measurement frequency, the measured value is equal to the average over the measurement interval. This average value, expressed in digital code, is formed at the output of converter 5. To increase the accuracy of control of the converter, the measurement time must be much less than the period of operation of the thyristor converter.

From the output of the converter 5, the binary code goes to the first input of the adder 8, the second input of which receives the binary code from the register 10.

Adder 8 performs the summation of binary codes from converter 5 and register 10, and the result of the sum is fed to the input of register 9. At the end of the measurement cycle of converter 5 from the output of

The controller 6 on the resolution write inputs of registers 9 and 10 receives a signal that records the results of the summation at a given cycle in registers 9 and 10. Two registers are used to increase the reliability of operation.

Thus, after each measurement cycle, a register is added to register 10.

45 code proportional to the average voltage over the interval of this measurement. During the period of operation in register 10, a binary code is accumulated, the value of which is proportional to

50 to the average value of the output voltage of the converter. From the output of register 10, the binary code is applied to the input of block 11. Source 14 forms a constant voltage, which sets

55 required average load voltage. From the input source 14, the voltage is fed to the input of block 13, the control input of which receives a code proportional to the period

bots converter. As a result, at the output of block 13, an analog signal is formed that is proportional to a given average value of the output voltage, taking into account the period of operation of the converter. Voltage with the output of block 13 is fed to the input of converter 12, where it is converted into a binary code, which is fed to the second input of block 11. When the current value of the average voltage becomes equal to the set value, block 11 outputs a signal that goes to node 4 and turns off the thyristor 2. Thus, a voltage is applied to the load 3, the average value of which for the period of operation is exactly equal to the specified output voltage.

The proposed device allows a significant increase in the accuracy of control of the thyristor converter, since the measurement period can be so small that the output voltage accurately replicates the nature of the ripple of the input voltage of the converter.

The control accuracy is improved due to the fact that all changes in the input voltage are taken into account and averaging takes place over a short measurement period, and the operation of the thyristor converter takes place directly in the control period, which allows for current fluctuations in the supply voltage and measurement of the load.

Q invention

Digital device for control and thyristor converter.

Compiled by V.Mironov Editor I.Shulla Tehred L.Serdyukova Corrector M.Sharoshi

Order 4835/55 Circulation 659 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, Projecto st., 4

15 20

25

thirty

Q

35

184

containing an integral unit of the output voltage, the input of which is intended to be connected to the output of the converter, a control signal source, a clock, pulse generator, and a counter, the first output of which is intended to control the power thyristor of the converter, characterized in that It is equipped with a multiplication unit, an analog-to-digital converter and a comparison unit, an integration unit of the input voltage is equipped with an analog-digital converter, an adder and two p Registrars, the counter is provided with a second output, and the input of the output voltage integration block is the input of the analog-digital converter of this block, the output of which is connected to the first input of the adder, the output of which is connected to the second register through the first register, the output of which is connected to the second input of the adder and is the output of the output voltage integration unit, which is connected to the first input of the comparison unit, the second input of which is connected via an analog-to-digital converter and a multiplication unit the output of the control signal source, the output of the clock generator is connected to the input of the counter and, in the output voltage integration block, to the clock input of the analog-digital converter and the write enable inputs of my registers, the reset inputs of which are connected to the second output of the counter, and the output of the compare block is designed to control the switching node of the converter.

Claims (1)

Claim A digital device for controlling a thyristor converter, comprising an output voltage integration unit, the input of which is designed to connect to the output of the converter, a control signal source, a clock, pulse generator and counter, the first output of which is designed to control the power thyristor of the converter, characterized in that, in order to improve control accuracy, it is equipped with a multiplication unit, an analog-to-digital converter and a comparison unit, an output voltage integration unit is equipped with an analog-to-digital converter, an adder and two registers, the counter is equipped with a second output, and the input of the output voltage integration block is the input of the analog-to-digital converter of this block, the output of which is connected to the first input of the adder, the output of which is connected to the input of the second register through the first register, the output of which is connected to the second input of the adder and is the output of the integration unit of the output voltage, which is connected to the first input of the comparison unit, the second input of which through an analog-to-digital converter and a multiplication unit are connected to the output of the control signal source, the output of the clock generator is connected to the counter input and, in the output voltage integration unit, to the clock input of the analog-to-digital converter and recording enable inputs of both registers, the reset inputs of which are connected to the second output counter, and the output of the comparison unit is designed to control the switching node of the Converter.