Electric Power Research Institute, China Southern Power Grid

China Southern Power Grid

China Southern Power Grid Technology Research Institute Co., Ltd.

Shukai Xu

Hong Rao

Yan Li

Chuang Fu

Changyue Zou

Weiwei Li

Xiaolin Li

Junjie Feng

Xiaobin Zhao

Shuangfei Yang

Jun Chen

Guiyuan Li

Juanjuan Wang

Qingming Xin

Weihuang Huang

Yuke Ji

Lingfei Li

Ting Hou

Method for determining parameter of a passive impedance adapter applicable to VSC-HVDC, including: S. obtaining VSC-HVDC impedance and VSC-HVDC impedance curve X(f) based on VSC-HVDC impedance; S. estimating upper limit value of the main capacitor in the passive impedance adapter; S. calculating adapter parameter curve X(f); S. determining value of the main capacitor and varying value of the main resistor until min[X(f)−X(f)] is maximized; determining whether min[X(f)−X(f)]>k holds; S. If min[X(f)−X(f)]>k does not hold, increasing the value of the main capacitor and performing steps S-Suntil min[X(f)−X(f)]>k holds when the value of the main capacitor is within the range of the value of the main capacitor, storing the parameters in an available parameter set; S. reducing the value of the main capacitor, and storing the parameters when min[X(f)−X(f)]>k holds in the available parameter set; S. selecting the available parameters from the available parameter set.

Method and device for determining parameter of passive impedance adapter applicable to VSC-HVDC

The present disclosure provides a parameter design method for a series passive impedance adapter applicable to a VSC-HVDC transmission system, to resolve the technical problem that high-frequency resonance may occur when impedance of a VSC-HVDC transmission system is mismatched with that of a sending-end or receiving-end grid. A parameter design goal of the present disclosure is that reactive power consumed by a series passive impedance adapter is not more than A times rated power of a converter, and a loss of the series passive impedance adapter in a fundamental wave is B times the rated power of the converter. The parameter design method for a series passive impedance adapter applicable to a VSC-HVDC transmission system in the present disclosure can realize a positive impedance characteristic within a concerned frequency band and completely eliminate a risk of harmonic resonance.

Parameter design method for series passive impedance adapter applicable to voltage source converter based high voltage direct current (VSC-HVDC) transmission system

Disclosed are a voltage source converter based high voltage direct current (VSC-HVDC) high-frequency resonance suppression method, system, and device. The method includes: when an effective value of an actually input alternating current (AC) voltage is reduced from a normal value to meet a preset condition, making the virtual electrical quantity completely equal to the actual electrical quantity, and performing full real-time tracking for the actual electrical quantity to improve dynamic characteristics of a power system at the moment of a fault; and after performing the full tracking for a period of time, if the effective value of the actual AC voltage is less than a preset threshold, performing adaptive tracking until the actual electrical quantity recovers to a stable value. The present disclosure can reduce a risk of high-frequency resonance of a VSC-HVDC, avoid deteriorating dynamic characteristics of the VSC-HVDC, and improve safety of fault ride-through of the VSC-HVDC.

Voltage source converter based high voltage direct current (VSC-HVDC) high-frequency resonance suppression method, system, and device

A voltage source converter based DC deicer and its control method are provided. The voltage source converter based DC deicer includes a connecting reactor, a modular multilevel voltage source converter based on a full H-bridge submodule, smoothing reactors, deicing disconnectors, a deicing bus, and a deicing AC line. The AC side of the modular multilevel voltage source converter is connected to an AC side bus through the connecting reactor, an isolation disconnector and a breaker. The DC side of the modular multilevel voltage source converter is connected to the deicing AC line through the smoothing reactors, the deicing disconnectors, and the deicing bus.

Voltage source converter based direct current deicer and controlling method thereof

A multi-functional automatic switching circuit for direct current ice melting and a switching method thereof are provided. The automatic switching circuit comprises at least one sub-switching circuit. The sub-switching circuit comprises a six-pulse current converter (R) with no saturable reactor, six reactors (L, L, L, L, L, and L), three three-phase knife switches (Sac, Sac, and Sac), and five single-phase knife switches (SV, SV, SV, SV, and SV). The sub-switching circuits in series connection or parallel connection, four direct current side switching knife switches (Sdc, Sdc, Sdc, and Sdc), an isolation knife switch (K), a breaker (QF) and a control and protection system (CP) may form an automatic switching circuit for six-pulse or twelve-pulse direct current ice melting. The automatic switching circuit with no saturable reactor reduces noise during operation, achieves mutually automatic switching among modes of reactor switching, ice melting and test, and may complete the through-flow test of the automatic switching circuit without switching in a power transmission line, thereby solving the problem of daily operation and maintenance.

Multi-functional direct current ice melting automatic switching circuit and switching method thereof

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Guangdong, China

Shukai Xu