04,28,2026 78 views
Three phase microcomputer relay protection testerMicrocomputer protection verification
(1) Wiring of microcomputer protection and testing equipment
Regardless of which software module of the three-phase microcomputer relay protection tester is used to test the microcomputer protection device, Ua, Ub, Uc, Un, Ia, Ib, Ic, In should be connected to the corresponding terminals of the voltage and current input circuits of the microcomputer protection device; Connect the tripping outlet (or trip A, trip B, trip C) and reclosing outlet of the protective device to the TA (or TB, TC, TD) and TE terminals of the tester, and connect the common terminal of the protective outlet (+KM) to the common terminal Tn of the tester.
(2) Current, voltage input circuit and polarity inspection
In the "Gradual Test" software module, set the voltage of each phase to 57.735V, with a phase angle difference of 120 degrees from each other; The current of each phase is, with a phase difference of 120 phase angle output. The microcomputer protection device should be able to read that the voltage values of each phase are 57.735V, the voltage values of each line are 100V, and the current values of each phase are.
(3) Whole group experiment
In the "whole group test" software module, various fault types, fault impedances (Z, φ mode or R, X mode), fault currents (usually), fault initial angles, zero sequence compensation coefficients Kx, Kr, etc., */instantaneous faults are set to simulate various types of fault inspection and protection actions.
After setting various parameters, press "confirm", and the computer will automatically calculate the fault current and voltage of each phase. Press "before fault" to output the normal voltage and current values before the fault (each phase voltage is 57.735V, current is 0A). Press "fault" to output the fault current and voltage, and apply them to the protection device. After the protection trip, the device resumes normal output. After the protection reclosing, if it is a * fault, the device will output the fault quantity again until the protection trips for the second time (permanent trip), and then output the normal quantity. The protection tripping, reclosing, and permanent tripping times are displayed in the test record area.
(4) Phase to phase distance test
In the "whole group test" software module, set AB, BC, CA, or ABC faults. When the fault impedance is set to 0.95 times the set value XJset of the inter phase distance impedance of a certain section, the protection should reliably operate according to the action time of that section. When the fault impedance is 1.05 times XJset, the protection of that section should reliably not operate.
(5) Grounding distance test
Exit the distance protection pressure plate and set AN, BN, or CN faults and Kx, Kr in the "whole group test" software module. When the fault impedance is set to 0.95 times the set value Zdset of the grounding distance impedance of a certain section, the protection should reliably operate according to the action time of that section. When the fault impedance is set to 1.05 times Zdset, the protection of that section should reliably not operate.
(6) Zero sequence protection test
The three-phase relay protection is uploaded to the exit zero sequence protection pressure plate. In the "whole group test" software module, AN, BN, or CN faults and Kx, Kr are set. When the fault current is set to 1.05 times the zero sequence protection setting value I0set for a certain section, the protection should reliably operate according to the action time of that section. When the fault current is 0.95 times I0set, the protection for that section should reliably not operate.
