Research On Key Technologies Of Distributed Real-time Simulation For Micro-grid

Real-time simulation is an indispensable tool in experimental research, design andplanning, evaluation and analysis for power systems. With the elaboration of powerelectronics technology, real-time simulation for novel power systems like micro-gridexhibited some characteristics such as stiffness, non-linear and high-speed computing,which brought difficulties and challenges to the development of real-time simulator. PCbased real-time simulator is far from satisfactory in high-speed solving, FPGA or DSPbased real-time simulator is difficult in modeling and have long develop cycle. Therefore,the distributed real-time simulation based on diversified cooperative processors has becomethe trend of the development of power system simulation. Based on the FPGA real-timesimulation board and PC real-time simulator operated on QNX RTOS, this paperdemonstrated the design and implementation of a real-time multi-rate co-simulationplatform for micro-grid converters, which took into account the speed, accuracy ofsimulation and modeling flexibility. The main work of this paper is as follows:1. This paper studied the real-time multi-rate simulation solution which solved thestiffness of micro-grid systems. Based on the state-space equations modeling methods, theauthor adopted time-domain segmentation solution, divided the micro-grid into rapidlycircuit subsystem and slow control subsystem, and finally used multi-rate real-timesimulation solvers to simulate it.2. The author accomplished the design and implementation of real-time multi-rateco-simulation platform based on FPGA and PC for micro-grid. This paper reveals thedesign of simulation platform architecture, simulation process, the QNX real-timesimulation engine and FPGA implementation of real-time multi-rate simulation interfacemodules, including high-precision clock synchronization and high-speed simulation dataexchange. The clock jitter in QNX simulator is below0.8microsecond, and simulation dataexchange period is10microsecond.3. Studied about design and implementation of the high-speed FPGA simulationsolvers, including linear state-space solvers and converter nonlinear solvers. This paperimplemented the discrete linear state-space solvers and converter nonlinear solvers basedon floating-point data format. The simulation step can reach200to500nanosecond.4. Experimental study on the real-time simulation of two level three phase inverter systems was launched. Taking offline accurate model as a benchmark, the multi-ratereal-time simulation platform and PC real-time simulation platform results were comparedin the simulation waveform and Euclidean error of simulation results. The results showedthat real-time multi-rate simulation platform can carry out real-time simulation tasks ofhigh-frequency converters with simulation step of0.2to0.5microseconds and preciselyelectromagnetic transients about1%Euclidean error.