SU1472967A1 - Device for connecting a switch in a specified voltage phase - Google Patents

Abstract

The invention relates to electrical engineering and is intended to control load switches, disconnectors and other switching devices. The purpose of the invention is to expand the scope, increase the reliability and accuracy of the device. When first turned on, the control unit 17 generates a command to turn on the thyristor key 1 to zero voltage. When the contacts close, the sensor 14 closes the contacts of the switch 2 and the adaptation unit 3 remembers the error of the contacts closing of the switch 2 relative to the zero voltage. The subsequent switching on of the device takes into account the compensation by the adaptation unit of the 3 switching-on errors of the contacts of the switch 2 with respect to the zero voltage. 3 il.

Description

The invention relates to electrical engineering and is intended to control load switches, disconnectors and other switching devices.

The aim of the invention is to expand the scope, increasing the reliability and accuracy of the device.

In FIG. 1 shows a block diagram of a device; Figs. 2 and 3 are timing diagrams explaining the operation of the device.

The device contains a thyristor starting key 1, a high-voltage switch with a switching coil 2, an adaptation unit 3, consisting of a pulse generator 4, counters 5. and 6, a comparison circuit 7, keys 8 and 9, the keys consist respectively of RS triggers 10, 11 and elements And 12, 13, The device also contains a contact closure sensor 14, the initialization unit 15 ,. a comparator 16 and a control unit 17, consisting, for example, of RS-flip-flops 18 - 20 and elements And 21, 22 _O

When the supply voltage is applied, the installation unit resets the triggers 18-20 of the control unit 17 and the counters 5 and 6 of the adaptation unit 3 ”. When the supply pulse is turned on, the trigger 18 of the control unit 17 is set to the output in the single state, and at the moment of the transition of the sinusoid voltage through the next zero, which is determined by the arrival of the pulse from the comparator 16, the trigger 19 is set to a single state through the element And 21. Due to the fact that the counters 5 and 6 of the adaptation unit 3 are reset, a single signal is present at the output of the comparison circuit 7 cash, allowing the passage of the switching pulse through the element And 22 from the output of the trigger 19 to the trigger 20, which is set to a single state, including the key 1, which by applying voltage to the switching coil of the switch 2 turns it on. Thus, the first turn on of the circuit breaker occurs at an arbitrary moment of time relative to the zero voltage on the contacts.

In FIG. 2 shows a timing diagram of the operation of the adaptation device when the circuit breaker is first turned on. Let the turn-on command occur at time t, then, in accordance with the above, the key 1 will open and voltage will be applied to the circuit-breaker coil at time t, Let T be the circuit breaker's own time, then at time t, the contacts of the circuit breaker and the closure sensor will be closed contacts will generate a signal, the unlocking key 8 (Fig. 1). From the generator 4, pulses are sent to the counting input of the counter 5 through the key 12, and at time t _e, the pulse counting will stop, since the key 8 will close with the arrival of the pulse from the comparator 16 at the moment the voltage passes through zero. As a result of this, the error of turning on the switch is not at zero voltage

The AT will be remembered by the 5 _O counter. The circuit breaker is tripped by a trip signal, while the triggers 18 - 20 of the control unit 17 are set to zero, the key 1 closes, removing voltage from the coil of turning on the switch 2. The switch is turned off (Fig. 1).

The second and all subsequent inclusions occur as follows (the timing diagram is shown in FIG. 3) "

The enable signal at time t _o , and at time t ' _o when a pulse arrives from comparator 16 (Fig. 1), trigger 19 is set to a single state. Since the codes of the counters 5 and 6 do not match, a zero is present at the output of the comparison circuit 7. At the output of the element NOT 23 of adaptation block 3, there is 1, two units from the output of NOT 23 and the element AND 21 of the control unit. The logical unit from the output of element And 24 opens the key 9, through which the pulses from the generator 4 are supplied to the counting input of the counter 6. The counter 6 starts to count the pulses coming from the generator 4. The resolving single pulse at the output of the comparison circuit 7 appears when the codes at the outputs of the counters match 5 and

6. The counter 5 stores information about the error of the inclusion of the diesel fuel, so the feed. voltage to the switching coil is delayed equal to the error time AT, i.e. during . Therefore, the closing of the contacts of the switch3 occurs at the time instant (Fig. 3). Thus, after the first switching on, the device adapts to this switch.

For, where ff _c

N the correct operation of the circuit does not fulfill the condition:

to ι

- pulse repetition rate of the generator 4;

- network frequency;

- the division ratio of the counters 5 and 6.

The minimum error of non-zero inclusion does not exceed half the period of the pulse repetition rate of the generator 4.

Each process of turning on the device leads to the addition of the deviation ΔΤ _Κ obtained in this switch to the value that is stored in the counter. As soon as the sum becomes equal (b _c = - trace period ^{z L} c of zero voltage nodes at the switching contacts), the counter is reset to zero, i.e. the adaptation unit performs the function of summing modulo the number ΐ of quantities ΔΤ *, as a result of which a deviation with respect to zero equal to C _s is perceived by the device as a zero deviation.

Claims (1)

Claim A device for turning the circuit breaker into a predetermined voltage phase, comprising a circuit breaker drive coil, a thyristor switch and a comparator, the thyristor switch output being connected to a circuit breaker drive, a. the comparator input - to the output for connecting the power circuit, characterized in that, in order to expand the scope, increase the reliability and accuracy of the device, a control unit, an adaptation unit, an initialization unit and a switch contact closure sensor are introduced into it; the control unit includes the first, second and third RS-flip-flops and the first and second element And; the adaptation unit contains a first key including a fourth RS-trigger and a third AND element; the second key, which includes the fifth RS-trigger, 'the first and second counters, the pulse generator, the element NOT and the fifth element And, and the output for connecting the source of the switching pulse is connected to the R-input of the first trigger of the control unit, and the output for connecting the pulse source the shutdown is connected to the S-inputs of the first, second and third triggers and the output of the installation unit to its initial state, the output of the first trigger is connected to the first input of the first element And, the output of which is connected to the R-input of the second trigger, the output of the second trigger with the first input of the second AND element, whose output is connected to the R-input of the third trigger, the output of which is connected to the control input of the thyristor key, the comparator output is connected to the second input of the first AND element of the control unit and the R-input of the fourth trigger of the first key of the adaptation unit, S-input the fourth trigger is connected to the output of the contact closure sensor, the output of the fourth trigger is connected to the first input of the third element And the first key of the adaptation unit, and the output of the third element And is connected to the C-input of the first count the adapter unit, the S-input of which is connected to the output of the installation unit in the initial state, the output of the first counter is connected to the first group of inputs of the comparison circuit of the adaptation unit, the R-input of the second trigger of the control unit is connected to the first input of the fifth element AND of the adaptation unit, the output of which is connected with the S-input of the fifth trigger of the second key of the adaptation unit, the R-input of the fifth trigger is connected to the R-input of the third trigger of the control unit, the output of the fifth trigger is connected to the first input of the fourth element And the second key of the adaptation unit , the second input of the fourth element And is connected to the pulse generator and the second input of the third element And the first key of the adaptation block, the output of the fourth element And is connected to the counting input of the second counter of the adaptation block, the reset input of the second counter is connected to the output of the installation block to the initial state, the outputs of the second counter connected to the second input terminal of the comparison circuit of the adaptation unit, the output of which is connected 1472967 θ of the control unit and through the element NOT of the adaptation unit - with a second input