A high-voltage line distributed capacitance measuring device and its measuring method

Abstract

The invention discloses a high-voltage line distributed capacitance measurement device and a measurement method thereof. The measurement device includes a phase voltage measurement circuit for measuring the phase voltage of a phase line to be tested and a ground capacitance current measurement circuit based on a bias capacitance Cf; The voltage measurement circuit is connected to the phase line to be tested; the ground capacitance current measurement circuit includes a bias capacitor Cf and a current detection unit for detecting the current flowing through the bias capacitor Cf, one end of the bias capacitor Cf is connected to the phase line to be tested and Its other end is grounded; Its measuring method comprises the steps: 1. Line phase voltage measurement before the bias capacitor is connected; 2. Line phase voltage measurement after the bias capacitor is connected; Carry out measurement; 4. Calculation of distributed capacitance. The invention has the advantages of reasonable design, convenient wiring, simple measurement method and accurate measurement result, and can measure the distributed capacitance of the high-voltage line under the electrified state, and the measurement process is safe and reliable.

Description

technical field [0001] The invention belongs to the technical field of distributed capacitance measurement of high-voltage lines, and in particular relates to a high-voltage line distributed capacitance measurement device and a measurement method thereof. Background technique [0002] At present, in my country's 6kV ~ 10kV power distribution system, the neutral point is not grounded or grounded through the arc suppression coil. Among them, the significant advantage of the neutral point ungrounded method is that the system can continue to operate for a short time when single-phase ground faults frequently occur (accounting for more than 60%). However, due to the existence of the ground capacitance of the power distribution system, it may cause intermittent arc grounding, ferromagnetic resonance and other neutral point displacement overvoltages, and even accidents, which will lead to breakdown of the weak insulation links of the entire power distribution system and equipment f...

AI Technical Summary

Problems solved by technology

Nowadays, many capacitive current measurement methods are used, and the additional capacitance method and the metal grounding method are usually used for measurement. However, in actual use, the former measurement method is complicated and difficult to operate; the latter is dangerous and has a low safety factor.

In summary, there is a lack of a high-voltage line distributed capacitance measuring device and its measurement method with simple structure, reasonable design, simple measurement method, and accurate measurement results, which can measure the distributed capacitance of high-voltage lines in a charged state, and the measurement process is safe and reliable.

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