SU873411A1 - Electric bistable relay - Google Patents

Description

(54). ELECTRIC TWO-STABLE RELAY

The invention relates to electrical engineering, in particular, to relay protection and automation of power systems, and can be used in emergency and warning signaling circuits. There are known commercially available RIS-EZM type signaling relays containing resistors, rectifier, differentiating unit and two-pole threshold. element (1. However, the known device requires the use of additional relays, and its noise immunity is low. The closest to the technical essence is an electric two-stable relay, A transformer with a primary winding which is connected to the input buses, a two-pole | 1st threshold element, the output of which is connected to the control input of the output block, resistors and power bus 2. However, this device is not very accurate and noise-proof. Enhancement of accuracy and noise immunity. For this purpose, an electric two-stable relay containing a transformer. The primary winding of which is connected to the input buses, a two-pole threshold element whose output is connected to two different polarized peak detectors, two differentiating blocks, a time delay block, and a transformer made in the form of a transreactor, the differentiating blocks connected to the secondary winding of the latter, the outputs through which the corresponding The resistors are connected to the summing input of a two-half threshold element, the power bus of which is connected to the power supply buses through a time delay unit. The drawing shows a functional block diagram of the proposed device. The device contains an input transformer 1 with a gap, a capacitor 2, peak detectors 3, 4 for positive and negative polarity, differentiating blocks 5, 6, resistors 7, 8, two-polar threshold element 9, block 10 time delay and output block 11.

In the initial state, the power supply to the relay is not applied, the output unit 11 in the state of non-operation does not emit a signal. When power is applied to the block .11 and through block 10 to the bipolar threshold element 9, the latter is set by itself and sets the output block 11 also to the non-operational position regardless of whether current is supplied to the primary winding of the transformer 1 or not. In the event that this current is supplied simultaneously with the power, the transient process flowing in the input circuit of the relay has time to fade until the supply voltage is applied to the two-pole threshold element through the time delay unit. This achieves the noise immunity of the relay: it does not work falsely when the power is supplied both in the presence and in the absence of input current. During short-term voltage drops, the time delay unit provides a fast discharge of the capacitor in the power circuit and thereby eliminates the false operation of the relay in the event that power is supplied simultaneously with the input signal.

If there is power at the relay, a stepwise increase in the current through the primary winding of the transformer 1. (When the circuit of the next blinker is closed, for example) a positive polarity pulse arises on the secondary winding, which charges the storage capacitor of the peak detector 4. When the voltage of the storage capacitor of the peak The detector, the differentiating unit b, outputs through a resistor 8 to the input of a two-pole YOR element 9 a current pulse, which puts the threshold element in a triggered state. At the same time, a signal appears on its output that unlocks the output block 11, i.e. the relay is activated. The relay returns to its original state using the contacts of an external time relay, which simultaneously feeds a signal to the substation signaling circuit.

If before the expiration of the time delay of this time relay the circuit of the last blinker dropped out, i.e. the malfunction was short-lived, the primary current in the winding of transformer 1 decreases, the secondary winding of its negative-polarity pulse-charge that charges the storage element of the peak detector 3, and through the Differentiating unit 5 and the resistor 7 the pulse returning it to the initial state, a blocking signal appears again at the input of the output unit 11, i.e. the relay returns to its idle state.

With its contact it returns the failed external time relay. Thus, the transmission of the signal to the substation signaling of short-term self-eliminating faults is prevented. This property of the relay allows to manage one common time relay without installing individual time elements in the chain of each blinker for

detuning from the alarm short-term faults.

 The use of a transreactor with a gap as an input transformer 1 reduces the dependence of the relay setting on the value of the current flowing through the primary winding of the transformer, and the capacitor 2 capacitance reduces the value of the variable signal at the output of the transformer. flow through its primary winding

rectified current (when powering the signal circuits from the rectifying units) with a periodic term (ripple) and provides the required relay parameters.

Regshizatsiya proposed relay

having a greater stability of the setpoint and noise immunity, will allow reducing the weight and dimensions of the relay, simplify the adjustment, save additional relays.

Claims (2)

1. Kakuevitsky L.I. and others. Reference Relay protection and automation. Relay-EZM. M.-L., SEI, 1968, p. 2. Kakuevitsky L.I. and other Handbook of protection relays and automation, Relay-E2M. M.-L., SEI, 1968, p. 224 (prototype).