Battery energy storage devices (ESDs) have become more and more commonplace to maintain the stability of islanded power systems. Considering the limitation in inverter capacity and the requirement of flexibility in the ESD, the droop control was implemented in paralleled ESDs for higher capacity and autonomous operation. Under the conventional droop control, state-of-charge (SoC) errors between paralleled ESDs is inevitable in the discharging operation. Thus, some ESDs cease operation earlier than expected. This paper proposes an adaptive accelerating parameter to improve the performance of the SoC error eliminating droop controller under the constraints of a microgrid. The SoC of a battery ESD is employed in the active power droop coefficient, which could eliminate the SoC error during the discharging process. In addition, to expedite the process of SoC error elimination, an adaptive accelerating parameter is dedicated to weaken the adverse effect of the constraints due to the requirement of the system running. Moreover, the stability and feasibility of the proposed control strategy are confirmed by small-signal analysis. The effectiveness of the control scheme is validated by simulation and experiment results.

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For improving launching velocity and efficiency of intercepting plate in active electromagnetic armor protective system, theoretically analyzing the main parameters that determine the change of electromagnetic force. Investigating the system dynamic changes in different pulsed power equipment driving manners. Combining different driving manners, the dynamic working process of the intercepting plate launcher are simulated, that adopting finite element analytic software Ansoft’s transient solution to simulate the dynamic process of intercepting plate. The maximum velocities obtained in the bipolar driving manner and in the single-polar driving manner are 12.61 m/s and 14.00 m/s respectively. Analysis shows that the effect of the electromagnetic force is not only related with the driving manners but also with the materials.

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