Insulation design method for multilayer starting resistor

Abstract

The invention discloses an insulation design method for a multilayer starting resistor, and relates to the field of high-voltage electrical equipment, and the method comprises the steps: building an equivalent circuit model of the starting resistor, and enabling the equivalent circuit model to be a circuit model formed by the series-parallel connection of a resistor, an inductor and a capacitor; arranging a low-damping voltage divider with the capacitance not larger than 800 pF at the top end of the starting resistor, dividing each resistor box of the low-damping voltage divider into a front section and a rear section, adopting standard lightning waves and standard operation shock waves as shock input, and calculating the voltage-sharing values of the front section and the rear section ofeach resistor box in a simulating mode. Setting the maximum lightning partial pressure of each section of resistor disc as U < thunder > max and the maximum operation partial pressure of each sectionof resistor disc as U < operation > max, respectively calculating non-uniform coefficients K < thunder > max and K < operation > max under the two partial pressures, and obtaining a non-uniform coefficient K from the K < thunder > max and the K < operation > max; and judging whether the insulation margin of the starting resistor needs to be increased or not according to the relationship between the non-uniformity coefficient K and the insulation design margin. According to the invention, on-time commissioning and safe and stable operation of the extra-high voltage flexible direct current project are ensured.

Description

technical field [0001] The invention relates to the field of high-voltage electrical equipment, in particular to an insulation design method for multilayer starting resistors. Background technique [0002] When the flexible direct current transmission system starts, there is a process of charging the capacitor in the MMC. In order to reduce the overvoltage and overcurrent generated on the circuit components during the charging process, it is necessary to set a starting resistor in the circuit, and after the charging is completed, the resistor The device is bypassed. The starting resistors used in the UHV flexible DC project are all multi-layer structures. With the continuous deepening of UHV flexible direct engineering construction, there are more and more start-up resistor breakdown faults. This kind of breakdown fault usually occurs in the stage of type test, factory test or system debugging, which seriously affects the progress of the project and the safe and stable ope...

AI Technical Summary

Problems solved by technology

This kind of breakdown fault usually occurs in the stage of type test, factory test or system debugging, which seriously affects the progress of the project and the safe and stable operation of the equipment

The current industry standard recommends that the design insulation margin be 1.1 times, but multilayer resistors will have uneven voltage distribution caused by capacitance, and the design of 1.1 times is far from enough

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