| Switching mode power supply is the core of switching converter. Switching converter is a closed-loop with high-end, discrete, nonlinear and time-varying systems, can not directly apply classical control theory analysis and design, this switch conditioning systems to dynamic analysis and design has brought great difficulties.80 years since the 20th century, since the modeling switching converter has been an important part of the study of power electronics, and has achieved many results.In the railway industry, more and more widespread use of switching power supply, electric power has been moving car controlled switching power conversion. Therefore, this paper for auxiliary control power to object to the average switching converter circuit modeling methods focus on research, help to optimize the performance of switching power supply and design efficiency.This article discusses the power for electric locomotive DC 110V control and auxiliary control power structures, and discusses the Buck switching converter's basic principle and structure, focusing on the average circuit modeling method, including the three-terminal PWM switch device modeling, an average equivalent circuit model method, averaging method of energy conservation. Based on the three models, the authors put forward a non-ideal converter in continuous conduction mode (CCM) of the circuit average model method, which considers both the switching devices in a variety of parasitic, but also simplify the model. A circuit averaging method exemplified by Buck converter is put forward to clarifying ideas and new methods of modeling the process, come to the non-ideal Buck converter in continuous conduction mode (CCM) under large-signal model. The model is steady state and dynamic small-signal characteristic analysis, and theoretical simulation and experimental results are compared to verify this model of DC-DC converter efficiency.Finally, the paper introduces the DC-DC switching converter in continuous conduction mode (CCM), the closed-loop control system. based on non-ideal Buck converter is a PID compensation network topology and parameter design, and conduct a small-signal characteristics of the simulation study and verify accuracy of the model and on the circuit design guide. |
