Abstract: Disclosed are a rapid prediction method and system for a commutation failure in a high voltage direct current transmission system (HVDC) based on a commutation failure risk factor, belonging to the technical field of commutation failure prevention in the high voltage direct current transmission system. The method can rapidly predict whether the commutation failure occurs after a fault occurs in a line-commutated converter-HVDC (LCC-HVDC) system, thereby supporting the subsequent prevention of the commutation failure. During the implementation, the method defines a conventional commutation area and an advanced commutation area, and calculates a commutation failure risk factor by integrating the conventional commutation area and the advanced commutation area, thereby predicting the commutation failure.

Abstract: The invention provides a method, device, apparatus, and storage medium for determining the overload boundary of MMC, which belongs to the field of DC transmission technology. The overload operation boundary of the MMC may be accurately determined, which is helpful to set the load level of the MMC reasonably in the design and operation process to ensure safe and efficient operation.

Abstract: The present invention provides a method and system of self-adaptive setting of closed-loop parameters for suppressing PV coupling harmonics, comprising: acquiring node voltages and node currents of PV grid-connected inverters; constructing harmonic coupling admittance matrix according to the node voltages and node currents; calculating an amplitude of each element in the constructed harmonic coupling admittance matrix; screening contribution sources of coupling harmonics according to the calculated amplitude of the each element; evaluating quantitatively harmonic admittance of the PV grid-connected inverter according to screened contribution sources; and, carrying out optimization iteration for double-closed-loop PI control parameters of inverter with objective of minimizing the coupling harmonics of the PV grid-connected inverter according to results of the quantitative evaluation of the harmonic admittance, to complete self-adaptive setting of closed-loop parameters for suppressing PV coupling harmonics.

Abstract: A fast-response photovoltaic (PV) simulator based on an improved deadbeat predictive current control (DPCC). Compared to actual PV modules, there is a response time at the output of the PV simulation. Currently widely used PV simulation have a long response time, which cannot meet the performance testing requirements of high-performance grid-connected PV inverters. Based on the energy balance of the inductor during the absorption and dissipation phases, the current control law of the output inductor in the PV simulation was studied in a single switching period, thereby establishing the required DPCC model. An integral compensation eliminates the steady-state error in current tracking caused by nonlinear factors such as time delay and mismatched parameters, enabling its wide application in engineering. For the proposed PV simulator, the transient response time can be reduced to 1.1 ms and significantly shorter than widely used PV simulation.

Abstract: The invention belongs to the technical field of harmonic contribution evaluation, and particularly relates to a system for tracing harmonic sources based on a cloud-edge-terminal collaboration and a method thereof, comprising: terminal module, collecting and transmitting real-time harmonic data to edge module; edge module, comprising plurality of edge computing servers deployed for the transformer substations and the transformer districts by units, realizing hierarchical control between edge computing servers according to voltage levels, and transmitting harmonic sources tracing task through hierarchical interactions between the edge computing servers; the edge computing server receiving harmonic sources tracing service request performs the tracing task, and feeds tracing result back to central module; and, central module, comprising cloud server receiving harmonic sources tracing service request initiated by user, determining edge computing server offloaded by the request, storing final tracing result from e

Abstract: The invention belongs to the technical field of harmonic contribution evaluation, and particularly relates to a system for tracing harmonic sources based on a cloud-edge-terminal collaboration and a method thereof, comprising: terminal module, collecting and transmitting real-time harmonic data to edge module; edge module, comprising plurality of edge computing servers deployed for the transformer substations and the transformer districts by units, realizing hierarchical control between edge computing servers according to voltage levels, and transmitting harmonic sources tracing task through hierarchical interactions between the edge computing servers; the edge computing server receiving harmonic sources tracing service request performs the tracing task, and feeds tracing result back to central module; and, central module, comprising cloud server receiving harmonic sources tracing service request initiated by user, determining edge computing server offloaded by the request, storing final tracing result from e

Abstract: A high voltage direct current (HVDC) transmission system comprises a first terminal comprising a first voltage source converter (VSC) having a first and second VSC terminals and a first line commutated converter (LCC) having first and second LCC terminals; a second terminal comprising a second VSC having third and fourth VSC terminals and a second LCC having third and fourth LCC terminals; and a transmission line pair comprising a positive transmission line that couples the first VSC terminal and the first LCC terminal of the first VSC and the first LCC, respectively, to the third VSC terminal and the third LCC terminal of the second VSC and the second LCC, respectively, and a second positive line that couples the second VSC terminal and the second LCC terminal of the first VSC and the first LCC, respectively, to the fourth VSC terminal and the fourth LCC terminal of the second VSC and the second LCC, respectively.