Central inverters

摘要

Various techniques are employed alone or in combination, to reduce the levelized cost of energy imposed by a power plant system. Solar energy concentrators in the form of inflated reflectors, focus light onto photovoltaic receivers. Multiple concentrators are grouped into a series-connected cluster that shares control circuitry and support structure. Individual concentrators are maintained at their maximum power point via balance controllers that control the flow of current that shunts this series connection. DC current from clusters is transmitted moderate distances to a centralized inverter. The inductance of transmission lines is maximized using an air-spaced twisted pair, enhancing the performance of boost-type three phase inverters. Cluster outputs are separate from individual inverters in massively interleaved arrays co-located at a central location. Step-up transformers convert inverter voltages to grid voltages, and small transformers provide isolation and voltage step-up only on receiver-to-receiver imbalance currents, typically <20% of the total current.

主权项

1. A central inverter comprising:
a housing; a plurality of individual inverters each removably coupled to a rack inside the housing, each of the plurality of individual inverters having an input and an output, the input of each individual inverter for providing electrical coupling to at least one of a plurality of photovoltaic receivers disposed remote from the housing, and the output of each individual inverter for providing an AC output; a cooling apparatus configured to provide common cooling to each of the plurality of individual inverters, wherein the cooling apparatus is configured to cool one or more of the plurality of inverters by producing a jet of water that impinges on a cooling plate that is in thermal communication with the one or more of the plurality of individual inverters; timing circuitry electrically coupled to each of the plurality of individual inverters, the timing circuitry configured to provide switch timing and synchronization between the plurality of individual inverters; and a central output for combining the AC output from each of the plurality of individual inverters.