Abstract: A voltage balancing circuit for capacitor banks or voltage cells connected in series. The circuit includes a DC-link with at least two capacitors or voltage cells connected in series and at least two emitter follower balancing circuits connected in parallel. At least one emitter resistor is provided between the emitter of each emitter follower balancing circuit and the mid-point of the DC-link. The gate emitter voltage applied to each emitter follower balancing circuit may be equal to its common gate voltage minus the voltage drop on the corresponding emitter resistor. The invention is also directed at a variable frequency drive for driving an electric motor or a power converter, having a corresponding voltage balancing circuit.

Abstract: A solar inverter is provided having a cooling module, a DC module, an inverter module and an AC module provided side-by-side within a chassis. The DC module includes an input accessible from a first side of the chassis and a disconnection switch on a second side of the chassis, with the input being configured to be connected to a DC solar power source. The AC module includes an output accessible from the first side of the chassis and a disconnection switch provided on the second side of the chassis. The cooling module is configured to pump a liquid coolant around the solar inverter in order to cool elements of the DC module, the inverter module and/or the AC module.

Abstract: A solar inverter is provided having a cooling module, a DC module, an inverter module and an AC module provided side-by-side within a chassis. The DC module includes an input accessible from a first side of the chassis and a disconnection switch on a second side of the chassis, with the input being configured to be connected to a DC solar power source. The AC module includes an output accessible from the first side of the chassis and a disconnection switch provided on the second side of the chassis. The cooling module is configured to pump a liquid coolant around the solar inverter in order to cool elements of the DC module, the inverter module and/or the AC module.

Abstract: A self-contained regenerative power system includes a fuel cell operative to generate electric energy from hydrogen and oxygen, generating water as a byproduct, and an electrolyzer operative to generate hydrogen and oxygen from water by consumption of electric energy. A bi-directional DC-to-DC converter interfaces between the fuel cell and the electrolyzer on one side and the system to be powered on the other. A switch selectively connects either the fuel cell or the electrolyzer with the bi-directional DC-to-DC converter. The products of the fuel cell process can be supplied to the electrolyzer process, and vice versa. Alternately, the self-contained regenerative power system comprises a unitary fuel cell and electrolyzer.

Abstract: A bidirectional interleaved DC to DC converter comprises positively coupled filter inductors that are coupled to a switching network that receives power from a DC power source, such as a battery. The positively coupled inductors are integrated as a single coupled inductor, which allows the DC to DC converter to convert DC voltage to various voltage levels with reduced voltage ripple, without the need for supplemental filter capacitors that are large and costly.

Abstract: A self-contained regenerative power system includes a fuel cell operative to generate electric energy from hydrogen and oxygen, generating water as a byproduct, and an electrolyzer operative to generate hydrogen and oxygen from water by consumption of electric energy. A bi-directional DC-to-DC converter interfaces between the fuel cell and the electrolyzer on one side and the system to be powered on the other. A switch selectively connects either the fuel cell or the electrolyzer with the bi-directional DC-to-DC converter. The products of the fuel cell process can be supplied to the electrolyzer process, and vice versa. Alternately, the self-contained regenerative power system comprises a unitary fuel cell and electrolyzer.