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DOE OSTI · 1870482

Fault Current Control and Protection in a Standalone DC Microgrid Using Adaptive Droop and Current Derivative

Augustine, Sijo·Reno, Matthew J.·Brahma, Sukumar M.·Lavrova, Olga
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Abstract

This report presents a novel fault detection, characterization, and fault current control algorithm for a standalone solar-photovoltaic (PV) based dc microgrids. The protection scheme is based on the current derivative algorithm. The overcurrent and current directional/differential comparison based protection schemes are incorporated for the dc microgrid fault characterization. For a low impedance fault, the fault current is controlled based on the current/voltage thresholds and current direction. Generally, the droop method is used to control the power-sharing between the converters by controlling the reference voltage. In this article, an adaptive droop scheme is also proposed to control the fault current by calculating a virtual resistance R droop , and to control the converter output reference voltage. For a high impedance fault, differential comparison method is used to characterize the fault. These algorithms effectively control the converter pulsewidth and reduce the flow of source current from a particular converter, which helps to increase the fault clearing time. Additionally, a trip signal is sent to the corresponding dc circuit breaker (DCCB), to isolate the faulted converter, feeder or a dc bus. The dc microgrid protection design procedure is detailed, and the performance of the proposed method is verified by simulation analysis.

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24 POWER TRANSMISSION AND DISTRIBUTIONCapacitorsCircuit faultsFault currentsFault detectionImpedanceMicrogridsVoltage control

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Augustine, Sijo, Reno, Matthew J., Brahma, Sukumar M., Lavrova, Olga. 2020-03-31. Fault Current Control and Protection in a Standalone DC Microgrid Using Adaptive Droop and Current Derivative. https://doi.org/10.1109/jestpe.2020.2984609

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