SU1499702A1 - Device for smooth turning on and off of converter - Google Patents

Abstract

The invention relates to electrical engineering and can be used to smoothly change the power of a load. The aim of the invention is to accelerate the process of entering the selected mode of operation while smoothly turning on and off the converter and simplifying the design of the device. The device contains the first and second input terminals 1 and 2, the first and second generators 3 and 4 of linearly varying signals, the comparison unit 5 and. pulse generator 6. Generator 4 contains a clock pulse generator 7, an element of OR-NOT 8 and a reversible counter 9., Comparison unit 5 contains two elements of comparison Yu and 11. In the device’s operating principle lies the vertical principle of controlling the thyristor converter, which consists in forming synchronously with each half-cycle of the mains voltage of a linearly varying signal, and comparing it with a control signal, which uses a linearly varying signal from the output of the generator 4, which sets the required speed l and the direction of change in power load. 2 Il. i SP C

Description

The invention relates to electrical engineering and can be used to smoothly change the power of a load, such as an electric heater, an electric motor, an electric motor, and other devices where certain operating conditions are required, over time.

The aim of the invention is to accelerate the process of exiting to the selected mode of operation while smoothly turning on and off the converter and simplifying the design of the device.

FIG. 1 shows a diagram of the device; in fig. 2 - time diagrams of his work.

The device contains the first and second input terminals 1 and 2, the first and

the second generator 3 and 4 of the linearly varying signals, the comparison unit - 5 and the pulse shaper 6.

Generators 3 and 4 of linear variable signals are digital blocks whose output signals vary from 0 (all bits are zero) to 1 (all bits are single).

Generator 3 generates a signal that varies linearly from minimum to maximum, equal to, respectively, O and 1, synchronized by pulses applied to terminal 1.

The generator 4, performed reversing 1K, on the leading edge of the input control signal produces

and with

1499702

the signal is linearly varying from O to 1, and on the falling edge produces a linearly varying from 1 to O. It contains a clock pulse generator 7, an element YLI-HE 8, a reversible counter 9,

The required rate of increase (decrease) of the load power is set by the frequency of the clock-pulse generator | Q ow 7,

Comparison block 5 contains the first and second elements of the comparison 10 and 11

The generator 3 can be implemented, for example, at the meter and the generator of 5 clock pulses, with the installation inputs. the counter is connected to the terminal 1 of the device, and the output Qj to the first input of the first element of the comparison 10. Under the action of a pulse 20 of the clock generator arriving at the counting input C, the contents of the counter begin to increase sequentially to the maximum value. As soon as the signal (code) of the counter reaches the maximum value (all bits are single), during the transfer a single signal that sets the counter and clock generator 30 before the arrival of the next sync pulse to terminal 1,

The input of the generator 3 podkpyuchey to. terminal 1, and its output is connected to the first input of the reference element 10, "The output of the clock generator

7through the first entry of the element OR NOT

8 is connected to the counting input of the reversible counter 9, the Addition input — the subtraction of which and the first input 40 of the comparison element 11 are connected to terminal 2; The output of the reversible counter 9 is connected to the second inputs of the comparison elements 10 and t1. The output of the comparison element 10 is connected to the input of the for- j world pulse generator 6 and the output of the comparison element 11 to the second input of the element OR-HE 8,

The input terminal 1 receives the sync pulses (Fig.2, 6) corresponding to the beginning of each voltage half-period (Fig 2, a) of the power source. neither These sync pulses are triggered by a generator 3, the linearly varying output signal (code) of which is compared on the element of comparison 10 with the output linearly varying signal (code) of generator 4, which is formed as follows

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Let the input control signal arriving at the first input of the comparison element 11 and to the input. Addition — subtraction of the reversible counter 9, which is in the single starting position, from terminal 2 changes from a single level to zero (FIG. 2 d). comparing the input control signal (O) and the output linearly varying signal (1) of the generator 4 at the output of the element of comparison 11 appears zero potential, the opening element OR-NOT 8, Clock pulses from the output of the generator 7 through the element OR-HE 8 begin enter the account With pleasing entrance down counter 9 operated in this case in If we subtract mode: Tani, the output schetchmka 9 starts to decrease successively from 1 to D (Fig. 2c).

The output signal (code) of generator .3 is compared on the element of comparison 10 with the output of the descending signal (code) of generator 4. As a result of comparison, the output of the element of comparison .10 produces a sequence of pulses (FIG. 2, d), the phase of which varies from f to O, t, e, the leading edge of the pulses is shifted to the left. - As soon as the output signal of generator 4 becomes equal to O, a positive (single) potential appears at the output of the comparison element It, and the signal O therefore, the output signal is Ora 4 remains constant and is equal to O. (FIG. 2, c). As a result, a comparison. the output of the linearly varying coi of the generator of constant 6 by the signal of the generator 4 at the output of the element of comparison 10 expires a sequence of pulses. . (figure 2, d), the phase of which is equal to Kulya.

When the input control signal goes from zero to one, a zero potential is formed at the output of the comparison element 11, Clock pulses from the output of the generator 7 through the open element OR NOT 8 begin to flow to the counting input C of the reversible counter 9 operating in addition, the output of counter 9 begins to increase sequentially from (FIG. 2, c).

As a result of comparing the output signal (code) of the generator 3 s. the output by the increasing signal (code) of the generator 4 at the output of the element of comparison 10 produces a sequence of pulses (Fig.2, d), the phase of which varies from B to Y, i.e. the leading edge of the pulses is shifted to the right.

When the output signal of the generator 4 reaches the maximum value 1, a positive (unit) potential j is generated at the output of the element of comparison 11 which arrives

to the second input of the element OR NOT 8, therefore, the output signal of the generator 4 remains constant and is equal to 1 (figure 2, c). As a result of comparing the output linearly varying signal of generator 3 with a single signal present at the output of generator 4, at the output of the element of Comparison 10, a sequence of pulses is produced (Fig. 2, e) whose phase is 7.

By changing the value of the input signal at terminal 2, get the required effect (consisting in a smooth HSMe-

The use of the proposed device allows automatically yes

any predetermined period of time will smoothly change the load power by smoothly varying and adjusting it from zero to

maximum (nominal) value and vice versa.

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The first generator is a pitch-changing signal whose input is intended to connect 11 pulses to the generator, and the output is connected to the first input of the first comparison element, the second input of which is connected to the output of the second generator of a linear-varying signal, it is intended to be connected to the control input of the converter, characterized in that, in order to accelerate the process of entering the selected mode of operation with smooth switching on and off The second generator of the linearly varying signal is made in the form of a clock generator, an OR-NOT element and a reversible counter, and the output of the clock generator is connected to the first input of the OR-NOT element, the output of which is connected to the counting input of the reversible counter, the input of the setting of the counting direction with the first input of the second comparison element and the source of the control signal, and the output of the reversible counter with the second input of the second comparison element is a second generator vkodom lineynr varying signal being an output of the first comparator is connected to the input of the pulse shaper, and the output of the second comparison element - to a second input of OR-NO element Q of the second oscillator linearly varying signal.

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Compiled by A.Kiselev Editor N.Timonin Tehred I.Didyk Corrector M.Paroshi

Order 1900 Circulation 394: Subscription.

VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. D. 4/5

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Claims (1)

The invention is a device for smoothly turning on and off a converter, a containing signal, the input of which is intended to be connected to a synchronizing pulse generator, $ and the output is connected to the first input of the first comparison element, the second input of which is connected to the output of the second generator of a linearly varying IQ signal, the second a comparison element and a pulse shaper, the output of which is intended to be connected to the control input of the converter, distinguishing 15 with the fact that, in order to accelerate the process of output An ode to the selected operating mode when the converter is turned on and off smoothly and the device design is simplified, the second ramp signal generator is made in the form of a clock pulse generator, OR-HE element and a reverse counter, while the output of the clock pulse generator is connected 25 to the first input of the OR element -HE, the output of which is connected to the counting input of the reversing counter, the input of setting the direction of the counting is with the first input of the second comparison element and 30 the source of the control signal, and the output of the reversing counter tchika with a second input of the second comparison element and is the output of the second generator 'lineynr varying signal, the output of the first comparison ⁵ is connected to the input of the pulse shaper element, and the output of the second comparison element - to the second input of OR-HE second generator linearly ₄ θ varying signal. (Jti SHZ Fig2 of