An adaptive digital control of current source inverter suitable for parallel processing inverter systems

This paper presents a description, steady state analysis, modeling and digital control design of a single-phase CSI power supply system in stand-alone mode. The multi-functional features associated with modern parallel processing inverter systems can be realized with the proposed bidirectional power conversion scheme. A detailed power circuit and controller description of the proposed power supply system are given. The steady-state analysis of the system is performed. Continuous-time state-space model of the system and discrete-time and DARMA models of a single-phase CSI are derived. An adaptive discrete-time controller for CSI is designed in order to obtain fast transient response and low total harmonic distortion of the output voltage waveform. An adaptive controller for DC choppers is designed in order to reduce the DC link inductor and optimize its dynamic performance. DC link and output filter design is performed and a systematic design procedure with a design example are presented. A number of simulations are presented to illustrate the performance of the system.