| Abstract |
An approximated sliding-mode controller for an inverter system consisting of parallel connected voltage source converters is presented. The model-based control design considers the whole inverter system and leads to a controller carrying out the control of the grid currents and circulating currents in separate tasks. Due to using hysteresis controllers for both of them, the scheme benefits from advantages of sliding-mode implementations such as fast response to reference changes and good suppression of disturbances. Thus, even sudden changes in the configuration caused by the loss of communication to one of the converters can be mitigated almost perfectly. Furthermore, it features a variable switching frequency avoiding unnecessary switching actions. Since it leads to an interleaved operation of the converters, it offers a lower harmonic content of the grid currents than a benchmark solution with individual hysteresis controllers for each converter with comparable losses. The results are verified experimentally. |
