A method and control device for removing an AC filter for high-voltage direct current transmission

Abstract

The invention discloses a removing method and a control apparatus for alternating current filters for high-voltage direct-current power transmission. A constant value of the total number of the alternating current filters which need to be removed is set according to requirements of alternating current voltage and reactive power; the input alternating current filters are divided into two conditions, including the alternating current filters which participate in the filtering function and the alternating current filters which do not participate in the filtering function; the number of groups of the various kinds of equivalent removing filters of the alternating current filters which participate in the filtering function is determined according to the minimum filter configuration table; if the number of the groups of the alternating current filters which do not participate in the filtering function is greater than or equal to the constant value of the total number of the alternating current filters which need to be removed, only the alternating current filters which do not participate in the filtering function are removed; or otherwise, the alternating current filters which do not participate in the filtering function, and the alternating current filters which participate in the filtering function in the residual groups are removed; when the alternating current filters which participate in the filtering function are removed, the number of the removing groups of each type is calculated according to the filtering performance; the alternating current filters are removed in sequence rapidly; and therefore, the overvoltage of the alternating current power grid can be effectively restrained, or the reactive power requirement can be rapidly satisfied.

Description

technical field [0001] The invention belongs to the fields of high-voltage direct current transmission and ultra-high voltage direct current transmission, and in particular relates to an AC filter cutting method and a control device for high-voltage direct current transmission. Background technique [0002] Thyristors are used as switching devices in high-voltage direct current transmission and UHVDC transmission. Since thyristors can only be turned on but not turned off, harmonics are generated while transmitting active power and a large amount of reactive power is consumed. Therefore, harmonics need to be filtered And provide reactive power, usually by configuring AC filters with different filtering performance. If the AC power grid fails to generate overvoltage, or the inverter connected to a weaker AC system or operating in an island is blocked, emergency shutdown, power drop or continuous commutation fails, it will be very difficult if the reactive power compensation eq...

AI Technical Summary

Problems solved by technology

If the AC power grid fails to generate overvoltage, or the converter connected to the weaker AC system or operating in the island is blocked, emergency shutdown, power drop or continuous commutation fails, it will be very difficult if the reactive power compensation equipment cannot be removed in time. prone to AC overvoltage

AC overvoltage will damage the high-voltage side AC filter, converter transformer, low-voltage side converter cooling and other equipment in the converter station, and even cause DC blocking in severe cases

[0003] The traditional AC filter removal strategy for HVDC and UHVDC transmission is obtained by checking the absolute minimum filter configuration table and the minimum filter configuration table. Overvoltage and meet the needs of fast reactive power regulation

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