2019年10月，米阳老师指导学生宋元元在“IEEE Transactions on Sustainable Energy”新录用一篇SCI一区论文，题为“The Adaptive Sliding Mode Reactive Power Control Strategy for Wind-Diesel Power System Based on Sliding Mode Observer”。
2019年11月，米阳老师指导学生颜丽在“IET Generation transmission distribution”新录用一篇SCI三区论文，题为“The Reactive Power Sharing Control for Islanded AC Microgrid Based on Fuzzy Adaptive Compensation Method”。
The Adaptive Sliding Mode Reactive Power Control Strategy for Wind-Diesel Power System Based on Sliding Mode Observer
Yang Mi, Yuanyuan Song, Yang Fu, Chengshan Wang
Abstract--Wind power may become the key development area of the renewable energy industry planning. Due to the fluctuated wind output power, the system parameter uncertainties and load disturbances, these may lead to the unstable operation of renewable energy power system for the larger voltage deviation. Therefore, the novel control strategy is proposed for the load side converter (LSC) of double-fed induction generator (DFIG) to improve the stability of power system, which is designed by taking advantage of adaptive sliding mode (SM) method and sliding mode observer (SMO). Furthermore, the static synchronous compensator (STATCOM) is also controlled through the designed adaptive SM reactive power controller, which can supply the reactive power compensation for the interconnected wind-diesel power system. Moreover, the LSC state variables need to be estimated by the SMO, which is constructed according to the established mathematical state model. Based on the estimated state variables, the designed reactive power controller is established for LSC by adaptive SM algorithm and fuzzy algorithm. The reactive power controller includes two parts. One is the designed SM controller by taking advantage of the estimated state variables and state control model. The other is micro-regulated part and the control signal is calculated by using fuzzy algorithm according to the system voltage deviation online. Experiment studies are performed by using RTDS to verify the effectiveness of the proposed strategy and assure the stability of wind-diesel power system under different operation conditions.
The Voltage Fluctuation Characteristic of Distributed Wind Generators and its Smoothing Control Strategy
Fu Yang, Wei Yuning, Jia Feng, Ye Jian, Shi Shuai
ABSTRACT:The uncertainty of wind speed will cause the fluctuation of output power of the distributed wind generators, which then leads to the fluctuation of the terminal voltage and finally degrade the power supply quality of the distribution network. The article focuses on a transfer function analysis for two types of wind energy conversion systems, which reveals the active power fluctuation on the change of wind speed, as well as a further investigation on the voltage fluctuation of point of common connection (PCC). Based on the analysis results, a P-Q joint control strategy is proposed, in which rotor kinetic energy is used to minimize the active power fluctuation so as to smooth voltage fluctuation from the very beginning. Additionally, the frequency-distinct reactive power control is proposed to reduce the deviation and suppress the fluctuation of the dynamic deviation.The effectiveness and advantages of the P-Q joint control strategy is demonstrated by simulations.
The Reactive Power Sharing Control for Islanded AC Microgrid Based on Fuzzy Adaptive Compensation Method
Yang Mi, Li Yan, Hangyi Cai, Yang Fu, Shuxin Tian, Chi Jin
Abstract--Due to reactive power irrational sharing issue resulting from the mismatched line impedances and unbalanced local loads of the inverters, the hierarchical coordination control strategy based on fuzzy adaptive compensation is designed to improve the accuracy of the reactive power sharing in the islanded AC microgrid. Firstly, in the local controller, the total active power and the average reactive power are obtained by the Initial Power Sharing Stage (IPSS) and the Secondary Power Sharing Stage (SPSS), respectively. Then, in the Power Balancing Stage (PBS), the average reactive power as the input of the fuzzy control can be used to adaptively adjust the voltage reference value in real time, so the rational sharing of reactive power may be achieved by using the designed control strategy. Furthermore, based on the classification of load fluctuation, the coordinated operation strategy is designed to deal with reactive power sharing for different load fluctuation conditions. Noteworthy, only the low-bandwidth synchronization signal from the central controller is used to the hierarchical control strategy, which can maintain characteristic of plug-and-play in the microgrid. Simulation and experiment results are presented to validate the effectiveness of the proposed strategy.