The evolution of power electronics and the wide availability of semiconductors allow researchers to test different power converter topologies for powering and controlling electrical machines. The parallel topology of power converters, which divides current into more branches, reduces load currents of the components, the volume of passive elements and current losses. Redundancy is added to the system, and efficiency is increased.
High parallel topologies of DC-DC converters are well-researched and already used in the industry. The development of parallel topologies of DC-AC inverters is focused more on multiphase converters for multiphase electrical machines. The high parallel topology of three phase converter does not have a lot of known solutions. Therefore, one high parallel three-phase converter was made and analysed as the object of this paper.
The development of a power converter combines different fields. Synchronization is made by PLL regulation of phase shift between the reference and synchronising signals. Synchronous serial communication is used in Daisy Chain configuration. For efficient communication, a special communication package and transmission algorithm were created. Regulation is based on field-oriented control. Programming in Code Composer Studio presented most of the work.
The number of converter’s parallel branches and their phase shift affects the total phase current ripple. Spectral analysis shows that the number of parallel branches reduces higher switching frequency harmonics when working in phase-shifted mode. Improvement does not increase proportionally with the number of branches. We can conclude that the optimal number of parallel branches for a such system is 3-4. Despite that, for some applications increasing the number of parallel branches is the fastest solution to increase output power.
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