Analysis of Transients and Validation of the Dynamic Models of a Phase Controlled DC Voltage Resonance Converter during Operation with Intermittent Current

Abstract

The article presents the results of ongoing investigations into the static and dynamic characteristics of a phase controlled resonance DC voltage converter (DCVC). For accurate calculation of transients, the fitting method in vector-matrix form was implemented. However, this method is rather cumbersome for practical applications and involves difficulties in obtaining the generalized parameters characterizing the DCVC dynamic properties that are necessary for development of DCVC closed-loop control systems. The article proposes a technique for analyzing the dynamic characteristics of a resonance DCVC operating in an intermittent current mode (ICM). The proposed technique is based on separating the processes into fast (in the resonance circuit) and slow ones (in the circuit of the output filter with the load) in combination with the averaging method. The article also proposes a simplified procedure for calculating the processes in the DCVC, according to which the mean value of current in the LC-circuit for a half switching cycle is determined, which is then used to calculate the voltage across the LC circuit capacitor at the half cycle end with the known value of this voltage at the half-cycle beginning, and also for calculating the process in the DCVC output circuit. The DCVC dynamic model is linearized, as a result of which discrete structural models suitable for synthesizing the DCVC control system and also a simple continuous model are obtained. The validity of the results is verified by determining the steady-state operation parameters according to the proposed procedure and comparing them with the previously obtained results.