Three-phase three-winding transformer induction voltage band partial discharge test parameter estimation method

Abstract

The invention relates to a three-phase three-winding transformer induction voltage band partial discharge test parameter estimation method. The method comprises the following steps that: 1, an equation set is simultaneously established, and a distributed capacitance value is solved; 2, the distributed capacitance value is converted into the end portion centralized capacitance of a three-phase winding; 3, high-voltage side test capacitive reactive power is calculated through the obtained centralized capacitance; 4, a longitudinal capacitance component is considered, so that total reactive poweris calculated; and 5, the equivalent inlet capacitance value of a three-phase three-winding transformer in a test is calculated according to the total reactive power; and step 6, a reactance value needing matching is solved on the basis of the obtained equivalent inlet capacitance value according to a parallel resonance principle. According to the method, the active power and active current of the three-phase winding under a three-phase simultaneous voltage application condition are calculated when the step 1 to step 6 are performed. The method of the invention is simple and clear. With the method adopted, the partial discharge test parameter of the transformer can be estimated according to a low-voltage class insulation test and related part delivery test data. The method has general adaptability.

Description

technical field [0001] The invention belongs to the technical field of intelligent operation inspection, and in particular relates to a method for estimating parameters of a three-phase three-winding transformer induction voltage band partial discharge test. Background technique [0002] With the continuous expansion of the scale of the power grid, the rapid growth of equipment installations, and frequent equipment quality problems, higher requirements are put forward for field tests. Among them, the transformer induced voltage with partial discharge test is a sensitive acceptance test. On-site handover tests and diagnostic tests are widely carried out. Since the transformer induced voltage with partial discharge test generally adopts low-voltage excitation, symmetrical or unilateral pressurized wiring, it needs to use large-scale test equipment such as variable frequency power supply, intermediate excitation transformer, and compensation reactor. However, due to factors su...

AI Technical Summary

Problems solved by technology

However, due to factors such as different capacities and different transformation ratios, field tests are carried out blindly without parameter estimation, and it is easy for the test equipment to fail to meet the test requirements, and even the on-site configuration of test equipment far exceeds the test requirements, resulting in waste of manpower and time.

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