University of Cape Town

Curtin University of Technology

Michel Malengret

Charles Trevor Gaunt

Chemmangot V Nayar

Hooman Dehbonei

Lawrence J Borle

A system and method for determining currents for injection into or extraction from a power network are provided. In a method conducted at a point of common coupling to the network, Th&#xe9;venin parameter data structures for each of a Th&#xe9;venin voltage, resistance and inductance, are compiled. An offset data structure including offset values is compiled for application to corresponding values of the Th&#xe9;venin voltage data structure to output an offset Th&#xe9;venin voltage data structure. Offset values are calculated to satisfy physical constraints associated with the network. An optimal point of common coupling power data structure and the offset Th&#xe9;venin voltage data structure are used to calculate current components for determining current for injection into or extraction from corresponding lines at the point of common coupling to reduce total electrical transmission losses of the network. The method may use the frequency domain and may include using frequency-dependent Th&#xe9;venin parameters.

Frequency domain-based determination of currents for injection into a power network

Systems and methods for injecting power into or extracting power out of a power network are provided. In a method, Thevenin parameters, in the form of at least a Thevenin voltage and a Thevenin resistance, of an equivalent Thevenin circuit are obtained with respect to each wire of the PCC. A total Thevenin power for all the wires is obtained, based on a specific amount of power at the PCC and the obtained Thevenin parameters. The method calculates an optimal current to be injected into or extracted from the PCC so as to inject or extract a specific amount of power. The calculation is based on the total Thevenin power and the Thevenin parameters. The method controls an injection or extraction of current at the PCC in accordance with the optimal current.

Methods and systems for power injection or extraction in a power network

A power conversion system includes a first converter having a DC side and an AC side and a second converter having a DC side and an AC side. The DC sides of the converters are connected in series with a battery connected in parallel across the DC side of the first converter. The AC sides of the converters are connected in parallel across an AC voltage grid. A DC generating power source is coupled across the DC sides of both converters. The first converter is bi-directional with the second converter being either an inverter providing DC to AC conversion or alternately a bi-directional inverter.

Growing community of inventors

Cape Town, South Africa

Michel Malengret