1. On-site maintenance items for microcomputer relay protection devices include:

(1) Measuring insulation

(2) Inspect the inverter power supply

(3) Check whether the curing procedure is correct

(4) Check the accuracy and balance of the data acquisition system.

(5) Check the digital input and output circuits

(6) Check list

(7) Whole group inspection

(8) Check with primary current and working voltage

According to the maximum and minimum impedance at each bus of the system, check whether the linearity of the microcomputer relay protection device can meet the requirements of the system. Special attention should be paid to the relationship between the secondary resistance of the current converter in the microcomputer relay protection device, the current proportional coefficient and the linearity of the microcomputer relay protection device.

The instruments and meters used in the inspection shall be managed by the inspectors, and special attention shall be paid to moisture-proof and shock-proof, and the errors of the instruments and meters shall be guaranteed to be within the specified range. Before use, you should be familiar with its performance and operation methods, and the use of advanced precision instruments should generally be supervised.

2. Design requirements:

(1) The microcomputer relay protection device should have the ability to resist electromagnetic disturbance.

(2) The microcomputer relay protection device should be equipped with online automatic detection. When there is no damage to any part of the microcomputer in the microcomputer relay protection device, the device abnormal information should be sent out, and the corresponding protection should be automatically locked when necessary. However, the design of the outlet circuit of the protection device should be simple and reliable. It is not advisable to add components that may reduce the reliability in order to achieve a complete self-check on the outlet circuit.

(3) All output terminals of the microcomputer relay protection device should not be electrically connected to its weak current system.

(4) The microcomputer relay protection device should be equipped with a self-recovery circuit, and it should be able to work normally through self-recovery when the program is dead due to interference.

(5) The microcomputer relay protection device should not lose the report when the power is disconnected.

(6) The microcomputer relay protection device should have a time synchronization function.

(7) For the deactivation section of the same type of microcomputer relay protection device, a uniform setting symbol should be specified.

(8) The microcomputer relay protection device of 110Kv and above power system should have the function of measuring the distance to the fault point.

(9) The secondary current transformer used in the microcomputer transformer protection device should be star connection, and its phase compensation and current compensation coefficients are realized by software.

(10) Both ends of the same line should be equipped with the same type of microcomputer high frequency protection.

(11) There should not be too many screen grouping schemes for the same kind of microcomputer relay protection device.