JPS6146111A - Inspecting system of relay - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for inspecting stationary offset motor relays.

A conventional offset Maw type relay is used for distance measurement, direction determination, step-out detection, field loss detection, etc., and has operating impedance characteristics as shown in FIG.

In the figure, operating region A shows the characteristics of a field loss relay, in which θl is fixed at 90 degrees, and offset value X1 and reach setting value X2 are each independently set. For operating region B, the offset value to the region is set to X3. The case where the jj-ch is changed by X4 Vc is shown, and the operating region C shows the distance relay characteristics where θl is replaced with 02, the offset value is Xs, and the reach is set to X6.

Among relays with such characteristics, those equipped with a check circuit are becoming popular as relays become stationary.

FIG. 3 shows a block diagram of a conventional field loss relay with inspection function. Detection input INI from protected target.

One of IN2 is used as a comparison reference and the other is used as a comparison input, and these manual INs and IN2 are used as filters 1 and 2t-, respectively.
The waveform is processed through the Here, the filters 1 and 2 are band-pass filters or low-pass filters (gRAK) as phase shifters, etc., and the circuit elements used differ depending on the protection function. 4
Then, the signals are added and subtracted from each other and passed through a shaping circuit that obtains a rectangular wave as the calculation result.

The outputs of both circuits 3 and 4 are ANDed by an AND circuit 5,
The phase difference between this output and the settling phase is determined by a phase comparator 6, and furthermore, a protection output OUT is taken out via a timer. The phase comparator 6 obtains a high level output when the output of the AND circuit 5 is at a high level for 1/2 time of one cycle (the outputs of circuits 3 and 4 are both on the same phase side), and the output of the AND circuit 5 is always low. It is configured to obtain a low level output when the output of the AND circuit 5 is at a high level for 1/4 of one period (the outputs of circuits 3 and 4 are on the opposite phase side), and the operation criticality is generally reached when the output of the AND circuit 5 is at a high level for 1/4 of one cycle. It is designed to operate when the level is high for more than that time.

The inspection circuit 7 normally returns the auxiliary relay 7A to apply inputs IN+ and IN2 to the filters 1 and 2, respectively, and outputs two-phase oscillation outputs (inspection signals) φ1. Filter 1 for φ2
, 2 is cut off. Then, during inspection, auxiliary relay 7A19 is activated and input IN1. The operation of circuits 1 to 6 is checked by applying oscillation outputs φl and φ2 to filter 1.2 instead of IN2. For example, circuit 1~
If the operating impedance characteristic of φ1.6 is in region A in FIG. φ2 is a signal having a phase and sharpness corresponding to the inside of region A.

Problems to be Solved by the Invention In the conventional inspection system, the inspection circuit 7 needs to be composed of five circuits to obtain inspection signals depending on the target relay, and each relay requires a different design. . Furthermore, even if the relays are of the same type, changing the specifications and characteristics requires changing the inspection circuit, which poses problems in terms of design and operation.

For example, when the offset set value and reach set value are changed depending on the eye-keeping target, when the characteristic person in FIG. 2 is changed to B, the output φ1 of the inspection circuit γ. It takes effort to change the size and phase of φ2.

In addition, in the conventional system, input signals and inspection signals are cut off and turned on using mechanical contacts of an auxiliary relay, so there is a problem in reliability due to the possibility of poor contact of the contacts.

Means and Effects for Solving Problems The present invention is characterized by individually inspecting the filter and the protection arithmetic circuit after the addition/subtraction circuit, and the filter has a diode connected to the filter so that the input signal is sufficiently higher than the input signal at the time of inspection. Apply a level inspection signal to force the input to the inspection signal, and apply the inspection signal in common to the protection calculation circuit at a level sufficiently higher than the filter output at the time of inspection through a diode. The filter is characterized in that the input is forced into a check signal, the output of the filter is detected by a level comparison circuit during inspection to check the operation of the filter, and the operation of the protection arithmetic circuit is checked by generation of the protection output.

Embodiment FIG. 1 is a circuit diagram showing an embodiment of the present invention, and the same parts as shown in FIG. 3 are designated by the same reference numerals.

The inspection circuit 11 has an inspection signal φ1t-diode 12. -1
Input signals IN1 . IN2
In addition, the inspection signal φ1 is applied to the filter 1 side inputs of the addition/subtraction circuits 3 and 4 via the diode 14. The output of the filter 1 is input to the adder/subtractor circuits 3 and 4 via the resistor 1st, and is also input to the level comparator 1.
6 is used as a comparison input.

The output of the filter 2 is input to the adder/subtractor circuits 3 and 40, and is also input to the comparison input of the level comparator 17.

The outputs of the level comparators 16 and 17 are input to an AND circuit IB, and the inspection command RD of the inspection circuit 11 is applied as a gate input to the AND circuit 1B.

This inspection command RD is passed through the logic inverter 9 to the output of the AND circuit IB and output to the OR circuit 200A, and the output of the OR circuit 20 is input to the AND circuit 21 together with the output of the phase comparator 6. Output ゛ is made the protection output OUT.

Here, the inspection command RD of the inspection circuit 11 is set to a low level during non-inspection to close the gate of the AND circuit 18, and a high level output is obtained to the OR circuit 20 through the inverter 9 to open the gate of the AND circuit 21.・Hold on, input signal IN! , INz from the phase comparator 6. In addition, the inspection signal φ1 of the inspection circuit 11 is input to the input signal IN1. IN2
The diodes 12 and 13 are at a sufficiently negative potential compared to
．． 14 is made non-conductive, and its effect on the input signal and filter output is cut off.

Then, at the time of inspection, the command RD is set to high level to open the gate of the AND circuit 18, and the inspection signal φ1 is set to a sufficiently large oscillation output compared to the input signal INl, lN2O level to filters 1 and 2 and the addition/subtraction circuit 3. , 4 to the phase and level of the check signal. The resistor 15 prevents the check signal passed through the diode 14 from flowing a current to the output of the filter 1, and causes the check signal to be applied to the addition/subtraction circuits 3 and 4 in priority to the output of the filter 1.

Therefore, during inspection, the output of filters 1 and 2 is the inspection signal φ
1, and the inputs of the addition/subtraction circuits 3 and 4 also become the output of inspection No. 48 φl and the filter 2 (filter output for φlK).

The outputs of the level comparators 16 and 17 are suppressed by the AND circuit 18 during non-inspection, and the filter 1
, 2 (output level relative to φtK) is within a predetermined range, a high level output is obtained, and when the level is lower or higher than that, a low level output is obtained, so-called window comparator operation is performed.

Therefore, at the time of inspection, it is possible to check with the level comparators 16 and 17 and the AND circuit 18 whether the functions of filters 1 and 2 are both normal, and the protection calculation circuits from addition/subtraction circuits 3 and 4 to phase comparator 6 are normal. Check the operation of the AND circuit 2 by giving an in-phase input to the addition/subtraction circuit 3.4 using the signal φ.
It can be checked as the output of 1.

Effects of the Invention According to the present invention, the inspection signal of the inspection circuit is inputted into the filter with priority over the input signal, and inputted into the protection calculation circuit with priority over the output of the filter, and the filter and the protection calculation circuit are individually checked. Therefore, only one inspection signal is required for one phase, and the same inspection signal can be used even when the offset or reach of the operating characteristics is changed or for different relays. In addition, switching by mechanical contacts is not required to apply a check signal, resulting in a highly reliable relay with a check function.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a complex diagram showing an example of the characteristics of an offset Maw type relay, and FIG. 3 is a circuit diagram of a conventional relay with an inspection function. 1.2... Filter, 3, 4... Addition/subtraction circuit, 6.
...Phase comparator, 7. Engineering 1...Inspection circuit, 16.17
...Level comparator.

Claims (1)

[Claims] In a stationary offset mode type relay that passes multiple input signals through filters and uses the filter outputs to perform protection calculations in a protection calculation circuit, during inspection, a check signal with a level sufficiently higher than the input signal is used as input to the filter. a first diode circuit that guides the inspection signal as an input to the protection calculation circuit at a level sufficiently higher than the output of the filter during inspection; A relay inspection method characterized by being equipped with a level comparison circuit for checking operation and individually inspecting the filter and protection calculation circuit.