Method, device and equipment for detecting three-phase imbalance fault of starting resistor and medium

Abstract

The invention discloses a method, a device and equipment for detecting a three-phase imbalance fault of a starting resistor, and a medium. The method comprises the following steps: detecting the real-time effective value of each phase of current of the three-phase starting resistor of a flexible direct current system; calculating a real-time dynamic non-uniform coefficient of the flexible DC system according to the effective value of each phase of current; and when the dynamic non-uniform coefficient is greater than a pre-calculated non-uniform coefficient threshold value of the three-phase current, determining that the starting resistor has a three-phase imbalance fault. Whether the resistance value of each phase of starting resistor is normal or not is judged by measuring the relative magnitude of the effective value of each phase of current on each phase of starting resistor, so that the three-phase imbalance fault of the starting resistor can be conveniently detected in time.

Description

technical field [0001] The invention relates to the technical field of flexible direct current transmission, in particular to a detection method, device, equipment and medium for a three-phase unbalanced fault of a starting resistor. Background technique [0002] The starting resistor of the flexible DC system is an important equipment of the flexible DC system. The starting resistor is put into use when the flexible DC system is started. After the AC circuit breaker is closed, the AC power supplies the flexible DC converter valve with uncontrolled rectification and charging through the starting resistor. After charging is completed Close the bypass isolating switch connected in parallel with the starting resistor to bypass the starting resistor. [0003] In order to maintain the starting balance of the three phases of the flexible DC system, the resistance values ​​of the starting resistors of the three phases are generally set to be the same. After closing the AC circuit ...

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Problems solved by technology

[0004] If the flexible DC system has internal short-circuit defects in the starting resistors of each phase, a small-scale short-circuit of the starting resistors occurs at the position of weak insulation every time it is started, but the system can still start normally because the short-circuited resistance is small; therefore, it is difficult to find three The unbalanced fault of the starting resistance of the phase, the equipment defect will expand after the small-scale short circuit of the starting resistance for many times, and will develop into an obvious short circuit, which will damage the equipment

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