Distribution network three-phase load unbalance adjusting control system

Abstract

The invention discloses a distribution network three-phase load unbalance adjusting control system which comprises a monitoring subsystem, an intelligent power distribution terminal and an intelligent phase-change switch. The monitoring subsystem and the intelligent power distribution terminal conduct data transmission through a wireless communication network, and the intelligent power distribution terminal and the intelligent phase-change switch conduct data transmission through the wireless communication network. By means of the distribution network three-phase load unbalance adjusting control system, the current and voltage information of a power distribution transformer in a distribution unit-area, three-phase four-wire branch lines and single-phase load can be acquired in real time, the unbalancedness of the distribution network three-phase current is obtained through calculation, on-line phase modulation is conducted according to the unbalanced load, and partial load of a phase of a large current is transferred to a phase of a small current, so that the purpose that the distribution network three-phase load unbalance is adjusted is achieved, the line loss is effectively lowered, and power supply quality is improved.

Description

technical field [0001] The invention relates to the technical field of power systems, in particular to a three-phase load unbalance adjustment system applied to distribution networks. Background technique [0002] The distribution network is an important part of the power grid that connects to the main grid and supplies power to users. Ensuring the stable operation of the distribution network under the state of three-phase load balance helps to improve the reliability of power supply of the power grid, the efficiency of system operation and the quality of terminal power. However, in the distribution network, most of the power users are single-phase loads or mixed single-phase and three-phase loads. The phenomenon of unbalanced three-phase load in the distribution network occurs, so that the three-phase currents are not the same, and an unbalanced current is generated on the neutral line of the distribution network, which eventually leads to an increase in the loss of the dis...

AI Technical Summary

Problems solved by technology

One is manual implementation, that is, by regularly detecting, recording and analyzing the load data of each phase, and then making targeted adjustments to the line; this method has the following disadvantages: 1) Time-consuming, laborious, inefficient, and difficult to adjust manually , safety cannot be guaranteed; 2) The three-phase load adjustment lag is inaccurate and cannot adapt to the randomness of users' electricity consumption; 3) The power needs to be cut off during the adjustment, and this offline adjustment method of line load distribution seriously affects the user's power supply reliability ;4) During the operation of each equipment in the station area, it is impossible to know the real-time operation situation, and cannot manage it online in real time, etc.

Another way is to set up an unbalanced current compensation device in the distribution network, which is based on the on-load capacity regulating transformer and has reactive power compensation capability, which can solve the problem of unbalanced three-phase current; but due to The unbalanced current compensation device has disadvantages such as high price, large self-loss, and inability to solve line loss, so it is not suitable for application in low-voltage distribution networks

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