An Optimal Method for Adjusting Parameters of Three-phase Load Automatic Balance

Abstract

The invention relates to an optimization method of an automatic balance adjusting parameter of a three-phase load. The method is characterized in that capacitance or inductance elements with different capacities are connected between a three-phase line and a neutral line and between phase lines; current active powers and reactive powers of all phases are measured and then numerical values of the capacitance or inductance elements with different capacities are calculated, wherein the elements are connected between the three-phase line and the neutral line and between phase lines. In the prior art, when an unbalancing phenomenon occurs at a three-phase load, currents of all phases are not identical and the mutual deviation of the phases of the three-phase currents is not 120 degrees and phases of the three-phase currents and voltages are not identical, so that the unbalancing phenomenon occurs at the three-phase currents; the current of the neutral line is not zero due to the unbalancing phenomenon of the three-phase currents, so that the reactive losses are increased, the wire losses and additional losses of the transformer are increased, and the output capacity of the transformer is reduced; and the certain phase of voltage or the certain two phases of voltages at the tail end is or are low severely. Therefore, the electrical energy quality is affected. However, with the provided optimization method, the defects can be overcome.

Description

technical field [0001] The invention belongs to the technical field of electric power engineering, and in particular relates to an optimization method for three-phase load automatic balance adjustment parameters. Background technique [0002] At present, the power supply mode of the low-voltage distribution network mainly adopts the three-phase four-wire system, and most users adopt the load mode of connecting the phase line and the neutral line. Since the connected three-phase loads are difficult to achieve equal balance, when the three-phase loads are unbalanced, it will inevitably lead to unequal currents in each phase, and the phase difference of the three-phase currents is not close to 120 degrees. The situation where the three-phase current with a large voltage phase difference is unbalanced. Unbalanced three-phase current leads to neutral line current not close to zero, increases reactive power loss, increases line loss and additional transformer loss, reduces transf...

AI Technical Summary

Problems solved by technology

Since the connected three-phase loads are difficult to achieve equal balance, when the three-phase loads are unbalanced, it will inevitably lead to unequal currents in each phase, and the phase difference of the three-phase currents is not close to 120 degrees. When the voltage phase difference is large and the three-phase current is unbalanced

Unbalanced three-phase current leads to neutral line current not close to zero, increases reactive power loss, increases line loss and additional transformer loss, reduces transformer output capacity, and seriously low voltage of a certain phase or two phases at the end affects power quality. as a result of

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