Abstract: A high-impedance fault positioning method and system based on synchronous Lissajous curve characteristics are provided. The method includes: acquiring a bus zero-sequence differential voltage and a feeder zero-sequence current of a faulty line; constructing a first Lissajous curve in a characteristic frequency band range based on the bus zero-sequence differential voltage and the feeder zero-sequence current; when the proportion of the faulty line is less than a set threshold value and the slope of the first Lissajous curve is negative, determining that high-impedance faults have occurred in the faulty line; constructing a second Lissajous curve based on the bus zero-sequence differential voltage and the section zero-sequence current, performing linear fitting on discrete data points of the second Lissajous curve to obtain a fitted curve; and when the slope of the fitted curve is negative for at least three consecutive periods, determining that high-impedance faults have occurred in the section.

Abstract: Provided is a physically synchronized solar-storage hybrid power generation system, belongs to the field of new energy technology, comprising: a PV module, comprising a PV unit and a first converter unit and a second converter unit electrically connected to the PV unit, respectively; an energy storage module, comprising an energy storage unit and a third converter unit, a first end and a second end of the energy storage unit being electrically connected to the first converter unit and the third converter unit, respectively; a grid connection module, a first end thereof is electrically connected to the second converter unit and the third converter unit, and a second end thereof is connected to a target large power grid; and a control module, being electrically connected to the PV module, the energy storage module and the grid connection module, respectively, and being configured to set control parameters of the solar-storage hybrid power generation system, and to adjust an operating state of the energy storage

Abstract: The invention discloses an electric vehicle charging pile control system and method considering grid frequency safety. The electric vehicle charging pile control system comprises a grid single-phase power input port, a voltage transformer, an AD conversion chip, a first data processor and a second data processor connected successively; the first data processor is further connected with a data real-time display device and a GPS/Beidou signal receiver respectively; the second data processor communicates with an electric vehicle charging pile and an electric vehicle battery pack respectively; and the second data processor is further connected with a man-machine interaction device.

Abstract: The invention discloses an electric vehicle charging pile control system and method considering grid frequency safety. The electric vehicle charging pile control system comprises a grid single-phase power input port, a voltage transformer, an AD conversion chip, a first data processor and a second data processor connected successively; the first data processor is further connected with a data real-time display device and a GPS/Beidou signal receiver respectively; the second data processor communicates with an electric vehicle charging pile and an electric vehicle battery pack respectively; and the second data processor is further connected with a man-machine interaction device.