Three-phase load unbalance intelligent adjusting device and method

Abstract

The invention discloses a three-phase load unbalance intelligent adjusting device and method, and the device comprises a DC side capacitor module, a main power module, a filtering module and a controlcircuit. The DC side capacitor module is connected with the main power module, the main power module is connected with the filtering module, and the filtering module is connected with the control circuit. The DC side capacitor module is formed by the series and parallel connection of multiple sets of capacitors. The main power module uses an IGBT, and an AC output side is connected with the filtering module. The device of the invention can realize accurate three-phase unbalanced processing and reactive power compensation, the response speed is less than 5ms, the power loss is less than 3%, the dynamic performance is good, and the device has the active balance intelligent adaptive control and parallel connection control mechanism. Moreover, on the basis of ensuring good governance effects,with simple topology and advanced control algorithms, the dynamic performance of the equipment is improved, and the volume and cost of the equipment are reduced.

Description

technical field [0001] The invention relates to a three-phase load imbalance intelligent adjustment device and method. Background technique [0002] With the development of social economy and the continuous improvement of people's living standards, the load of distribution transformers (referred to as distribution transformers) is also increasing day by day. Since most of the current household appliances are single-phase electrical equipment, the time period for putting them into use cannot be determined, and the load connection and distribution are uneven, the three-phase unbalance phenomenon on the low-voltage side of the distribution transformer often occurs. According to investigation and sampling, during the period of heating in winter and cooling in summer, the imbalance rate of many station areas is above 30%, and some even exceed 80%. This not only leads to the increase of power loss, but also directly leads to overheating and burning of equipment in serious cases, ...

AI Technical Summary

Problems solved by technology

[0007] This patent (CN107069731A) adopts a split capacitive three-phase four-wire inverter topology, the structure is relatively simple, but the current tracking control circuit design directly compares the current command value under the abc coordinate system with the instantaneous value, and then performs Tracking control, since the current in the abc coordinate system is sinusoidal, no static error tracking cannot be achieved, and the three-phase unbalance control and reactive power compensation performance of the device is average

[0008] Both of the above two patents use SPWM modulation (sinusoidal pulse width modulation), and the DC side voltage utilization rate is low, resulting in large DC side capacitance and increasing the cost of equipment.

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