Parameter design method and device of passive impedance adapter applicable for flexible direct current

Abstract

The invention discloses a parameter design method and device of a passive impedance adapter applicable for flexible direct current. The parameter design method comprises the following steps of S1, acquiring flexible DC impedance, and obtaining a flexible DC impedance curve X(f) according to the flexible DC impedance; S2, estimating an upper limit value of a main capacitance value in the passive impedance adapter; S3, calculating the parameter curve X<adapter>(f) of the adapter; S4, determining a value of the main capacitor, changing the size of a main resistor until min[X(f)-X<adapter>(f)] ismaximum, and judging whether min[X(f)-X<adapter>(f)] is larger than k or not; S5, increasing the value of the main capacitor if the min[X(f)-X<adapter>(f)] is not larger than k, executing the steps S2to S4, and storing a parameter in an available parameter set; S6, reducing the value of the main capacitor, and storing the parameter when the min[X(f)-X<adapter>(f)] is larger than k in the available parameter set; and S7, selecting an available parameter from the available parameter set. By the parameter design method, the parameter design of the passive impedance adaptor can be achieved, so that the positive impedance characteristic within the full frequency band is achieved, and the harmonic resonance risk is completely eliminated.

Description

technical field [0001] The invention relates to the technical field of flexible direct current system optimization, in particular to a parameter design method and device for a passive impedance adapter suitable for flexible direct current. Background technique [0002] my country's hydropower resources are mainly concentrated in the southwest region, and the electricity load in the eastern region is relatively concentrated. The implementation of long-distance and large-capacity "west-to-east power transmission" is an objective requirement for my country to optimize resource allocation and solve the reverse distribution of energy and power loads. It is also an objective requirement to turn the resource advantages of the underdeveloped western regions into economic advantages and promote the common economic development of the eastern and western regions. important measures. DC transmission adopts power electronic conversion technology to convert clean hydropower at the sending...

AI Technical Summary

Problems solved by technology

[0005] (1) In the existing technology, grid impedance is related to factors such as operation mode, load, and power flow, and its impedance amplitude and phase may vary in a wide range. Because the operation mode arrangement is related to multiple factors, and AC faults such as lightning strikes may also Causes forced changes in the operating mode, restricting the operating mode to avoid harmonic resonance is difficult to implement as a long-term solution

[0006] (2) Adding auxiliary equipment will bring additional costs, and there is currently no public auxiliary equipment design method

However, under the characteristics of long control link delay, adding a low-pass filter cannot completely avoid the risk of high-frequency resonance

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