Electric circuit and associated method for regulating power transfer in a power grid
AssigneeCity University of Hong Kong
InventorsYuanbin He, Shu-Hung Henry Chung, Chun-Tak Lai
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Abstract
An electric circuit for regulating power transfer in a power grid includes a compensator circuit arranged to be connected between outputs of one or more power sources and a point of common coupling in the power grid. The compensator circuit is arranged to detect one or more electrical properties associated with the outputs and one or more electrical properties associated with the point of common coupling; and provide, based on the detection, a voltage output to emulate a resistor for suppressing filter resonance associated with the one or more power sources and to reduce equivalent impedance of the power grid.
Claims18
An electric circuit for regulating power transfer in a power grid, comprising:
- a compensator circuit arranged to be connected between outputs of one or more power sources and a point of common coupling in the power grid;
- wherein the compensator circuit comprises:
- a voltage source;
- a power converter having a switching network, arranged to regulate voltage of the voltage source to provide a voltage output to emulate a resistor for suppressing filter resonance associated with the one or more power sources and to reduce equivalent impedance of the power grid;
- and
- a controller for controlling the switching network, the controller is arranged to:
- detect current io through the outputs of the power sources and voltage νPCC at the point of common coupling;
- determine a first voltage based on the detected current io;
- determine a second voltage based on the detected voltage νPCC;
- filter the first and second voltages using a band-stop filter;
- detect voltage νdc of the voltage source;
- compare the detected voltage νdc with a reference voltage νdc,ref to determine a difference signal;
- and
- generate gating signals for controlling the switching network based on the filtered first and second voltages and the determined difference signal, so as to regulate the voltage output.
A method for regulating power transfer in a power grid using an electric circuit, the electric circuit including a compensator circuit arranged to be connected between outputs of one or more power sources and a point of common coupling in the power grid, the compensator circuit comprising a voltage source;
- a power converter having a switching network, arranged to regulate voltage of the voltage source to provide a voltage output;
- and a controller for controlling the switching network, the method comprising:
- detecting, using the controller, current io through the outputs of the power sources and voltage νPCC at the point of common coupling;
- determining, using the controller, a first voltage based on the detected current io;
- determining, using the controller, a second voltage based on the detected voltage νPCC;
- filtering, using the controller, the first and second voltages using a band-stop filter;
- detecting, using the controller, voltage νdc of the voltage source;
- comparing, using the controller, the detected voltage νdc with a reference voltage νdc,ref to determine a difference signal;
- generating, using the controller, gating signals for controlling the switching network based on the filtered first and second voltages and the determined difference signal, so as to regulate the voltage output;
- and
- providing, by the voltage source, based on the detection, the voltage output to emulate a resistor for suppressing filter resonance associated with the one or more power sources and to reduce or cancel equivalent impedance of the power grid.
Dependencies are inferred from the claim text.