Arc suppression coil device on basis of single-phase matrix converter

Abstract

The invention relates to an arc suppression coil device on the basis of a single-phase matrix converter. The arc suppression coil device is connected between a neutral point of a power grid and the ground. The arc suppression coil device is characterized by comprising the single-phase matrix converter composed of a two-way switch, an electric reactor and a controller, wherein an input end of the single-phase matrix converter is connected with the neutral point of the power grid, and an output end of the single-phase matrix converter is connected with the electric reactor; and the controller is connected with the single-phase matrix converter and sends out trigger signals to control the connection and disconnection of the two-way switch of the single-phase matrix converter so as to control voltages and currents at the two ends of the electric reactor and to change working currents of the arc suppression coil device. Compared with the prior art, the arc suppression coil device has the advantages of quickly compensating a current at an earth point, being short in response time, less in low-order harmonic, and the like.

Description

Technical field [0001] The invention relates to an arc suppression coil device for power grids, in particular to an arc suppression coil device based on a single-phase matrix converter. Background technique [0002] In my country's medium voltage distribution network, single-phase grounding faults account for more than 80% of the total faults, so it is very important to manage single-phase grounding hazards. One of its main measures is to install an arc suppression coil at the neutral point of the power grid to compensate for the ground current and use the grounding line selection device to quickly find the grounding branch and eliminate the fault. The arc suppression coil is a device connected between the neutral point of the power grid and the earth. When a single-phase ground fault occurs in the power grid, the arc suppression coil outputs inductive current to offset the capacitive current flowing through the ground point, thereby extinguishing and suppressing the arc Rekindl...

AI Technical Summary

Problems solved by technology

Beijing: China Electric Power Publishing House) and other documents point out: the air gap adjustment type requires a precise mechanical transmission mechanism, and the response time is long, and the vibration and noise are relatively large; the turn adjustment type requires an on-load switch to adjust the number of coil turns, and the inductance cannot be continuous Adjustment; Capacitance-adjusting type may lead to unstable compensation current due to the decrease of parallel capacitor capacity; Phase-controlled type needs to add additional filtering device due to harmonic generation

[0004] After searching the existing patents, it was found that the Chinese patent document number CN201805225U recorded a stepless adjustment arc suppression coil based on IGBT control. Winding, insulated gate bipolar transistor IGBT modules are connected in series on the secondary winding circuit; when in use, the working winding is connected to the neutral point of the grid system, and the insulated gate bipolar transistor IGBT module is connected in series on the secondary winding circuit, although it is not necessary Install a filtering device, but the secondary winding needs to add a commutation circuit during chopping control

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