Phase testing method for alternating current high-voltage power supply circuit by using single-pole phase testing device

Abstract

The invention discloses a phase testing method for an alternating current high-voltage power supply circuit by using a single-pole phase testing device, and belongs to the field of measurement. The method comprises the following steps of: determining a virtual ground potential by using a common grounding end in a control circuit of the single-phase phase testing device; measuring potential difference between an alternating current power supply circuit and a virtual ground; and shaping and amplifying a signal, then performing phase locking according to a unified clock signal t and further comparing, calculating, storing, displaying and outputting phase difference between every two phases of alternating current circuits. The entire test device is convenient to carry and light in weight and is wirelessly and remotely operated; high-voltage insulation is truly realized; the aims of safety, reliability, quickness and accuracy are fulfilled; a phase testing measurement result of the method can be qualitative and quantitative; and the method can be widely applied to the field of measurement of the high voltage / ultrahigh voltage alternating current power supply circuit.

Description

technical field [0001] The invention belongs to the field of measuring electromagnetic variables, in particular to a method for measuring the phase sequence of a three-phase AC power supply line. 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 and test items 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 overhaul...

AI Technical Summary

Problems solved by technology

[0011] To sum up, it can be seen that the existing "nuclear phase" operation method or technical scheme, one can only verify the voltage (or voltage difference) between the two power sources, and can only qualitatively distinguish the phase difference, and cannot quantify the phase difference. It belongs to the qualitative "nuclear phase", in other words, it can only be "qualitative" but not "quantitative".

[0012] In addition, the existing technical solutions are usually "bipolar", that is, the phase verification device must measure two power supply lines at the same time (referred to as "double-head wiring" in the industry), the workload of the on-site measurement is large, and the measurement personnel need to be more Climbing or going up and down the pole / tower, the connection and disassembly of the measurement device wiring is complicated, error-prone, heavy recording workload, insufficient safety margin, and can no longer meet the requirements of the nuclear phase work of the existing high-voltage power grid

[0013] At the same time, for the "wireless" nuclear phase method, due to various electromagnetic interferences on site, the measurement signal is easily interfered, which also affects the accuracy of the measurement results, and based on reasons such as insulation and operation safety, the existing wireless "nuclear "Phase phase" measuring device can only be applied to 220,000 volts voltage level line, and the nuclear phase device of higher voltage level cannot be achieved and realized

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