Control device and control method of alternating current and direct current power supply system and alternating current and direct current power supply system

Abstract

The invention discloses a control device and a control method of an alternating current and direct current power supply system and the alternating current and direct current power supply system, the alternating current and direct current power supply system comprises a power transmission line, a sending end converter, a receiving end converter and a plurality of switches, and the control device comprises a sending end control unit and a receiving end control unit, the sending end control unit adopts double closed loop control of a dc voltage outer loop and a current inner loop and is used for controlling the direct-current side voltage of the transmitting-end converter to be constant, and meanwhile, neutral-point potential closed-loop control based on zero-sequence voltage injection is introduced to ensure neutral-point potential balance of the transmitting-end converter; and the receiving end control unit adopts double closed-loop PI control of a voltage outer loop and a current inner loop, is used for controlling alternating current voltage output of a receiving end converter, provides voltage support for a load, introduces current feedback and voltage feedforward, and is used for eliminating current coupling and load disturbance voltage influence. By means of the mode, the control device can improve the power supply reliability and effectiveness of the alternating-current and direct-current power supply system, and the voltage requirement of an end user is met.

Description

technical field [0001] This application relates to the field of power distribution technology, in particular to a control device, a control method and an AC / DC power supply system for an AC / DC power supply system. Background technique [0002] In the early stage of power grid construction, remote end users have low power consumption and low demand for power quality due to limited living standards. Therefore, the voltage drop of these users' power consumption is not obvious, and their power demand is not harsh. However, with the improvement of people's living standards, household loads are increasingly diversified, refined, and large-capacity, resulting in the centralized use of high-power loads, which makes the voltage drop of long-distance distribution lines obvious, and the voltage drop problem of end users is prominent. In addition, the use of various high-power electric loads often has a certain periodicity, so that the problem of low terminal voltage also occurs periodi...

AI Technical Summary

Problems solved by technology

[0005] This application provides the control device, control method and AC / DC power supply system of the AC / DC power supply system, so as to solve the problem of insufficient terminal voltage of the AC / DC power supply system in the prior art, which cannot guarantee The effectiveness and reliability of the DC power supply method

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