Research on Multi-source DC microgrid Distributed Group Control Strategy for Pumping Well Cluste

Abstract

Due to the pumping units' dual role as alternating loads and new energy sources, multi-source DC microgrid pumping unit well clusters experience increased fluctuation in voltage and power as well as peak and valley values that are superimposed. This work presents a distributed cooperation strategy based on the grouping weighted moving average algorithm for pumping unit well groups in multi-source DC microgrid. Centralized control program is implanted in the RTU of the single well controller of each pumping unit, and the communication of each single well is realized by SCADA system to construct the distributed well group system. The real-time power values of the pumping well group are calculated by grouping the power values and granting weighted weights to each group, using the total power fluctuation threshold of the well group as the control target, and further using a weighted moving average algorithm to predict the next power value and form a table of predicted real-time power spectra. According to the power value in the community power spectrum table, the inverter frequency is proportionally adjusted downward to achieve the power peak before deceleration to reach; after crossing the power peak, the frequency is raised in the same way to accelerate the compensation to achieve the power valley before acceleration to reach, that is, acceleration compensation, and finally achieve the power peak and valley values of the bus system to level off, and further learn to reach the set impulse, and finally form a stable impulse. Through laboratory testing and field application in Shengli XIN-11 block application proved: the group control software module not only effectively suppresses the active power peak and valley values and voltage fluctuations of the bus system, the active power fluctuation rate range decreases by more than 70%, the DC bus voltage fluctuation range decreases by more than 80%, but also reduces active power by about 6% without increasing the cost of new hardware.