Remote signaling acquisition implementation method of relay protection device with adjustable starting value

Abstract

The invention relates to a remote signaling acquisition implementation method of a relay protection device with an adjustable starting value. An analog-to-digital converter is added between secondaryoutput and CPU input of a photoelectric coupler; the analog-to-digital converter converts the secondary output voltage of the photoelectric coupler into digital quantity and inputs the digital quantity to the CPU; the CPU compares the acquired voltage value with a positive threshold value and a negative threshold value, and judges whether remote signaling deflection occurs or not; when the currentremote signaling output state is 0, the voltage is detected to rise and is higher than the positive threshold value, and the remote signaling output is set to be 1; and when the current remote signaling output state is 1, the voltage is detected to be reduced and is lower than a negative threshold, the output state is set to be 0. The output of the analog-to-digital converter is collected by theCPU, and remote signaling deflection judgment is carried out; the output has hysteretic characteristics relative to the input, and the anti-interference performance is improved; two sets of positive thresholds and negative thresholds with rated values of 110V and 220V can be set, and can be selected for use according to actual field requirements, so that the compatibility of 110V and 220V is realized.

Description

technical field [0001] The invention belongs to the technical field of power system grid operation and maintenance, and in particular relates to a method for realizing remote signal collection of a relay protection device with an adjustable starting value. Background technique [0002] Remote signal collection is one of the important functions of relay protection devices, mainly used for the collection of binary inputs in substations, and the voltage rating is generally DC 220V or 110V. It is required that the start-up voltage of the remote signal collection of the relay protection device should not be greater than 0.7 times the rated voltage value, and should not be less than 0.55 times the rated voltage value. The starting power of the strong current input circuit involving direct tripping should not be lower than 5W, and can withstand the standard lightning wave voltage of 1.2 / 50μs of 5KV, and the surge immunity test of test level A (test pulse voltage: total Mode ±4KV, ...

AI Technical Summary

Problems solved by technology

The difference in the transmission ratio will lead to a large difference in the starting voltage of the circuit using the same resistance, and it is difficult to ensure that they are all within the allowable range

In this way, it will be very troublesome to mass-produce the device. It is necessary to test the start-up value of each remote signal and replace the resistance of the circuit that does not meet the requirements.

In some occasions, it is necessary to achieve compatibility between rated values ​​of 220V and 110V without changing the circuit, which cannot be achieved by traditional methods

The traditional method can only adjust the starting value of the remote signaling acquisition of the relay protection device by adjusting the hardware circuit parameters; the relay protection device using the traditional method needs to replace the resistor again because the remote signaling starting value is not suitable after the production is completed; the traditional The method cannot achieve 220V and 110V rated voltage compatibility

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