Optimization Of Power System Digital And Physical Hybrid Simulation Interface

The power system operation level of safety,stability and economy is improving continuously,at the same time its scale becomes larger,its structure is more complicated,and the trend of power electronics domination is significant.Relatively,the power system nowadays raises a higher demand for traditional simulation method.Digital and physical hybrid simulation,combining real-time digital simulation and physical dynamic analog simulation,gets into good graces.The hybrid simulation is the unification of two single simulation methods,but its problems of implementation scheme and effectiveness of simulation results are prominent especially.Divided object of power system is established in the form of digital model and physical analog system respectively,and the interface system constitutes a bridge as their inter-relationships.It is necessary to optimize the performance of interface system to ensure the effectiveness of simulation results on the premise that digital and physical subsystems are built accurately.In this thesis,the interface algorithm is discussed,and the entire process from segmentation to introduction of the algorithm is explained.Making use of Thevenin's equivalent circuit of power system,transfer function of the hybrid simulation is deduced,and stability condition of voltage source ideal transformer model interface algorithm is received by Nyquist stability criterion.The implementation principle of digital side and physical side is introduced according to selected interface algorithm,and a wide universal platform infrastructure of the hybrid simulation as well as its integrated control system is further proposed.Starting with phase correction,the performance of the interface system is optimized.The characteristic of voltage and current signal transmission channel as well as the feasibility of phase correction is analyzed by introducing the interaction process of the hybrid simulation.The model of parameter optimization of phase correction is proposed,and performance evaluation index system is set up correspondingly.Optimize the performance of the interface system in the respect of dc component elimination.The control strategies of every links of the interface system on the physical side are introduced,enumerating the possible error sources,and demonstrating the limitation that restraining dc component.Adopt the control strategy of dc component elimination equipped with capacities of stability judgment and oscillation suppression,and special operating conditions of the hybrid simulation could be accommodated.Based on the inverter power unit and the hybrid simulation platform,verified experiments are developed to contrast the effect before and after the optimization.The results indicate that the proposed optimization strategies work with reliability and effectiveness.