Three-phase load balancing electric meter box

Abstract

The invention provides a three-phase load balancing electric meter box, wherein a processor compares the unbalance rate of a phase current and the absolute value of the unbalance phase current with apreset threshold value separately and correspondingly to judge whether the unbalance rate and the absolute value exceed the threshold value or not, if the unbalance rate and the absolute value exceedthe threshold value, switching is executed, a relay set is controlled to act, and a relay set with the minimum three-phase unbalance rate is switched to. Moreover, the three-phase load balance electric meter box has various switching combination forms, so that the optimal operation mode can be pre-judged in advance, and blindness in the adjustment of other adjustment modes is avoided. The processor evaluates all possible operation modes through the high-speed operation and selects an optimal mode for investment, so that the selection of the device is optimal. The processor can obtain a presetvalue or an optimal switching strategy in advance, and also can set an adjustment reference value for switching, thereby avoiding the frequent adjustment. The commissioning phase can be selected according to the comprehensive evaluation of historical data and the like, so that the switching frequency is remarkably reduced. And through a two-phase switching method, the number of executive components and the operation burden of the processor are reduced.

Description

technical field [0001] The invention relates to the technical field of power systems, in particular to a three-phase load balancing electric meter box. Background technique [0002] At present, most of the residents in rural areas and some urban areas use low-voltage power supply methods with public distribution transformers as the core. Rural public distribution station area refers to the power supply mode in which a single or multiple distribution transformers provide power supply for multiple users, most of which are single three-phase transformers for multiple users with power loads less than 3 kilowatts. Single-phase 220-volt living power. This type of low-voltage power supply system generally has a small single-user load, large real-time changes, a large number of users, and a wide distribution range. The distribution of three-phase loads is difficult to control. The three-phase load of the distribution transformer is unbalanced, and the terminal voltage of the user ...

AI Technical Summary

Problems solved by technology

[0003] The output of the transformer is insufficient, and the power supply cannot reach full capacity, resulting in a waste of power resources

It also causes overheating of the transformer and saturation of the iron core, which affects the life of the transformer.

The unbalanced three-phase load will also cause the user's voltage quality to fail to meet the requirements, affecting their normal power consumption

The unbalanced three-phase load increases the copper and iron loss of the transformer, and the loss of the low-voltage line increases

In this way, as a three-phase incoming line method, it is difficult to maintain the three-phase balance due to the continuous changes in the load of each user, and the above-mentioned problems still occur.

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