Research on Improved Deadbeat Control Strategy Based on Interpolation Prediction and Online Inductance Identification Aiming at the problem of control delay and inductance deviation, which exist in the traditional deadbeat control of the fullbridge circuit, an improved deadbeat control strategy was proposed. An improved Newton interpolation prediction algorithm was proposed to compensate the delay problem of deadbeat control, and an online inductance identification algorithm based on double frequency sampling was proposed to correct the inductance deviation. A mathematical model of deadbeat control for fullbridge inverter was established; besides, the performance of different interpolation prediction algorithms was analyzed. An online inductor identification model is established, on the basis of which the online inductance identification compensation formula is derived. It is indicated that an output constant current of 10xe2x80x89A is available with the deadbeat control relative error of only 0.2%, the gridconnected power factor up to 0.999, and the output currentxe2x80x99s total harmonic distortion of only 2.37%. The prototype experiment shows that the output currentxe2x80x99s total harmonic distortion is as low as 2.403% and the power factor is as high as 0.998. The results show that the improved deadbeat control strategy can effectively improve the control accuracy and the quality of gridconnected power.

Active and Frequency Control Strategy of Improved Droop Control in Islanded Microgrid The traditional droop control will reduce the frequency of the system, and will seriously affect the power quality in an independent microgrid consisting of a variety of distributed power sources. However, if the frequency recovery time is too long, the frequency does not return to the power frequency and will drop seriously and deviate from the rated value when the next load disturbance occurs. In order to solve these problems, this paper proposes a fuzzy PI active and frequency control strategy based on the traditional droop control. The degree of frequency offset is taken as the reference amount, and its control parameters are dynamically adjusted to quickly restore the frequency to the stable value. In addition, the first function term of the power and droop coefficient is established to replace the fixed droop coefficient to prevent the frequency from crossing the boundary. Finally, the effectiveness of the proposed strategy is verified by MatlabSimulink simulation. The improved control strategy can make the system frequency stable in power frequency and improve the dynamic performance of the system.