Compact and efficient transformerless power conversion system

The power conversion system (PCS) developed by the author is a new technology that efficiently transforms power between AC and DC. The conversion process permits the input voltage level to be stepped up or down without the use of magnetic core transformers. The transformation is accomplished using solid state switching devices, capacitors, air-core inductors and an intelligent control system. The technology is based on the property of resonance charging, thereby permitting the use of self commutating switches. The current through the switches, being sinusoidal in nature, has a low dI/dt. This permits the use of slower, less expensive thyristors, similar to those used in high voltage phase control applications. Using these components, a highly efficient inverter can be constructed for a variety of large utility applications.