Three-grade low-voltage power distribution network voltage control device and control method thereof

Abstract

The invention discloses a three-grade low-voltage power distribution network voltage control device and a control method thereof. The device comprises an integrated control system, a three-phase unbalance control device, a dynamic reactive compensating device and a line voltage adjusting device. The three-phase unbalance control device, the dynamic reactive compensating device and the line voltage adjusting device are successively connected in the line of the low-voltage power distribution network. The integrated control system performs coordinated unified control on each device, thereby performing voltage control on the low-voltage power distribution cabinet according to a three-step sequence of line voltage adjusting, three-phase unbalance control and dynamic reactive compensation. According to the control method of the three-grade low-voltage power distribution network voltage control device, first-step voltage adjustment, second-step three-phase unbalance control and third-step dynamic reactive compensation are successively performed according to data which are acquired by each device. The three-grade low-voltage power distribution network voltage control device can realize electric energy quality unified and comprehensive control on three-phase unbalance, low power factor, low end voltage, etc. Furthermore the three-grade low-voltage power distribution network voltage control device and the control method have advantages of simple control realization, high control effect, capability of suppressing resonance and preventing overregulation, etc.

Description

Technical field [0001] The invention relates to the technical field of low-voltage power distribution, in particular to a three-stage low-voltage power distribution network voltage management device and a control method thereof. Background technique [0002] With the development of society, the inductive load among the user loads connected to the low-voltage distribution network is rapidly increasing. Due to the prevalent three-phase load imbalance, low average load rate, high no-load loss, Problems such as large power supply radius and poor terminal voltage quality have been accompanied by the development of low-voltage distribution networks, and the problems of low voltage, low power factor and high loss have gradually emerged, and have gradually developed into a bottleneck problem that plagues the development of low-voltage distribution networks. Therefore, the voltage quality of the low-voltage distribution network and the management of energy saving and loss reduction are pa...

AI Technical Summary

Problems solved by technology

[0004] (1) Resonance: The generation of resonance overvoltage will cause great harm to the power grid, such as causing the fuse of the voltage transformer to be blown, the voltage transformer to be burned, the insulation of the power grid equipment to be damaged, etc., and even cause phase-to-phase short circuit, protection device malfunction, etc.

The generation of resonance will not only cause serious damage to power devices and equipment, but once resonance occurs, it can only be cut off forcibly or stopped until a certain device is damaged;

[0005] (2) Cause overshoot: When the rural power grid changes from normal to abnormal operation mode, or from abnormal to normal operation mode, due to the inconsistent action time of different equipment, it will also cause voltage overshoot or oscillation, making reactive power compensation devices and other equipment Continuous frequent switching reduces the service life of the equipment and causes power waste. At the same time, the continuous change of the voltage will also cause impact on the line, load, etc., and cause loss to the equipment.

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