An AC/AC direct power conversion topology having multiple power grid connections with adjustable loading

Normally, a power converter has one supply port to connect to the power grid and one or multiple output ports to connect to AC loads that require variable voltage and variable frequency. As the trend on the energy market is towards deregulation, new converter topologies are needed to allow independent producers/consumers to connect to multiple distribution grids in order to optimise the electricity price, as this will vary during the day from one power distribution company to another one. It will be needed to have a load that can smoothly adjust the power consumed from each power grid in order to minimize the overall energy cost or in case of special applications, to improve the system redundancy. Also, having a generator that can simultaneously feed fractions of its power into multiple grids which are not coupled (different voltage, frequency, displacement angle) and continuously adjust these fraction power will be a necessary feature on a deregulated energy market. This paper presents a new topology of a power converter based on the direct power conversion concept, which is able to connect to multiple grids and provide complete decoupling between without circulating power between the grids, adjust continuously the power sharing and provide sine-wave in and sine-wave out operation. Additionally, it minimizes the size of passive components and does not need electrolytic capacitors for energy storage, which has impact on increasing the converter lifetime.