Non-power-cut detection device and method for secondary winding error of multi-channel mutual inductor

Abstract

The invention relates to a multichannel mutual inductor secondary winding error non-power-off detection device and method, and the device comprises three independent detection units. The detection unit comprises a central processing module, a change-over switch, and an excitation change loop, a current injection loop, a first voltage acquisition module and a second voltage acquisition module which are electrically connected with the central processing module; the excitation change loop and the current injection loop are connected in parallel and then connected into the winding loop, and the change-over switch is used for selectively connecting the excitation change loop or the current injection loop into the winding loop in series; the first voltage acquisition module and the second voltage acquisition module are used for acquiring voltage signals on two sides of a secondary loop; the excitation change loop is used for changing excitation conditions of the loop and acquiring excitation current signals; the current injection loop is used for injecting current into the winding loop and acquiring an injection current signal; and the central processing module is used for calculating a mutual inductor error according to the excitation current signal, the injection current signal and the voltage signals at the two ends of the characteristic node.

Description

technical field [0001] The invention relates to an uninterrupted detection device and method for secondary winding errors of a multi-channel transformer, belonging to the technical field of power equipment detection. Background technique [0002] The error verification of the transformer in operation is traditionally required to verify the accuracy of the transformer in the case of a power outage. Power outages of 10kV and above power supply lines in substations often lead to load loss, and there is a problem of difficulty in power outages. The secondary winding of the transformer is generally divided into three types: measurement, measurement and control, and protection. They have different levels of accuracy and are strictly prohibited from being interchanged during use. Moreover, each type of winding has multiple taps, so the wiring of the secondary winding must be correct. However, due to the negligence of design, construction, and acceptance, the protection device and ...

AI Technical Summary

Problems solved by technology

[0006]The advantages of this prior art are: 1. The traditional live detection operation has a large safety risk, and the standard operation process of live connection is complicated, which is harmful to the safety of on-site operators and equipment. Both pose a threat and reduce the safety risk of operation; 2. Compared with the traditional live detection equipment, the equipment designed by this patent is lighter, more flexible and easy to transport. 3. The live detection cannot monitor the operation error online in real time

The disadvantages are: 1. The calculation process of the excitation impedance and the secondary load impedance is not described in the patent, and the voltage and current signals measured according to the patented detection method cannot accurately distinguish the secondary load impedance and the excitation impedance; 2. The scheme requires and The current transformers are installed together in the secondary winding circuit of measurement, protection, measurement and control, etc. before putting into operation. If it is necessary to monitor the operation error of all current transformers, it is necessary to install multiple sets of equipment and increase investment.

3. Because the equipment described in this plan needs to be installed at the same time as the secondary winding circuit of the current transformer, when there is a wiring error in the secondary winding circuit of the current transformer, it will affect the correct analysis of the monitoring equipment

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