| Due to the merit of small volume, light weight and low cost, mobile generator is widely used as backup or mobile power supply. Inverters of mobile generator in parallel operation can increase the capacity as well as reliability of the system and has become a hot research topic in so-called distributed power supplies (DPS).In this thesis, the design scheme of a DSP-controlled inverter applied in mobile generator is presented at the beginning and then the design method of control system is mainly discussed. Equivalent output impedance model of instantaneous voltage and current closed-loop controlled inverter is established on the foundation mentioned above.How the values of LC filter, parameters of PI regulator and feedback coefficient etc. affect the external characteristic of inverter is analyzed in detail. Non-linear factor of inverter are also discussed and corresponding solutions are put forward.Based on the establishment of inverter equivalent model, theoretical calculation of power circulating flow and current circulating flow is carried through successively. The former calculation indicates that phase difference of output voltage brings active power difference between models while amplitude difference brings reactive power. Analysis of circulating current indicates that inductor value of output filter as well as wire impedance has great influence on circulating current.With the help of analysis, simulation and experiments, this thesis puts forward a design scheme of parallel inverter models based on CAN bus, it is a kind of interconnected and master-slave mode and can increase parallel models arbitrarily. Primary experiment of prototype indicates that this scheme is easy to realize and the synchronization and current-share perform well.
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