Shared-frequency asynchronous phase-checking method

Abstract

The invention discloses a shared-frequency asynchronous phase-checking method and belongs to the field of measurement. The method comprises the following steps of: generating a synchronous standard phase signal serving as a third-party reference by means of a commercial power network; sequentially acquiring a voltage phase signal between each phase of a system power supply and each corresponding phase of the to-be-checked power supply; performing phase comparison on the measured voltage phase signal and the third-party reference at the time to obtain a voltage phase differential value; comparing the voltage phase differential value between each phase of the system power supply and each corresponding phase of the to-be-checked power supply to obtain a comparison phase difference; and judging whether each phase of the system power supply and each corresponding phase of the to-be-phased power supply belong to the same phase or not according to the value range of the phase difference so as to obtain the conclusion whether the system power supply has the same phase as the to-be-phased power supply or not. The asynchronous phase-checking method can check phases of systems with the same or different voltage levels, can test whether a power supply loop has the failures, such as 'phase failure' and the like, or not, can check phases in different places and widens the application field of the routine phase-checking tests.

Description

technical field [0001] The invention belongs to the field of measurement of electromagnetic variables, in particular to a measurement method for measuring the phase angle between the voltages of two AC power sources. Background technique [0002] Phase sequence, that is, the sequence of phases, is the sequence in which the instantaneous value of alternating current changes from negative to positive and passes through zero. [0003] The "Phase Check" test is a test test to check the phase / phase sequence of the three-phase power supply between two power sources, and is one of the basic experiments of the power system. [0004] If the AC power supplies with different phases or phase sequences are "parallel" or "closed", a large current will be generated, and the huge current (commonly known as "circulating current") will cause damage to electrical equipment. [0005] Therefore, for newly built, rebuilt, and expanded substations and transmission lines, and before the line is ov...

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Problems solved by technology

[0014] 3. There are many personnel involved in a "nuclear phase" test, and the labor cost is very high;

[0015] 4. There are many steps in the whole test work, which takes a long time and affects the effective power supply time of the whole power supply system;

[0016] 5. The nuclear phase operation has certain risks, especially the wired phase nuclear method, and the cooperation and coordination of personnel must be considered;

[0017] 6. The distance between the two power points should not be too far. According to the actual operation experience, the distance between the two core phase rods should not exceed 10 meters.

[0019] For example, how to ensure the smooth completion of the nuclear phase test without increasing or even reducing the workload of the nuclear phase personnel while considering the reduction of nuclear phase personnel? The traditional high-voltage system phase verification method requires at least two gears / groups of testers to complete, and it can only be used for power equipment of the same voltage level, which has many limitations in the scope of application

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