Parameter determination method and system for extra-high voltage direct current cable superposition impact test device

Abstract

The invention discloses a parameter determination method and system for an extra-high voltage direct current cable superposition impact test device. The parameter determination method comprises the steps of guiding the type selection of a voltage source of the extra-high voltage direct current cable superposition impact test device according to the test demands of an extra-high voltage direct current cable test sample segment, analyzing the efficiency and characteristics of the extra-high voltage direct current cable superposition impact test device, and selecting a reasonable resistance-capacitance isolation device for parameter configuration. Parameters of the voltage generator and the impulse direct-current voltage isolation element in the extra-high voltage direct-current cable direct-current voltage superposition impulse test device are determined by performing parameter calculation on the extra-high voltage direct-current cable and performing circuit simulation on the direct-current superposition impulse voltage test device, so that effective isolation of impulse voltage and direct-current voltage is realized, the output efficiency of the direct-current superimposed impulse voltage test device is brought into full play, thereby guaranteeing that the amplitudes of impulse voltage and direct-current voltage on a cable sample meet test regulations, and satisfying the requirement for the test device when an extra-high-voltage direct-current cable is subjected to a direct-current superimposed impulse voltage test.

Description

technical field

[0001] The invention relates to the technical field of insulation performance detection of power cable equipment, and more specifically, to a method and system for determining parameters of a UHV DC cable superimposed impact test device. Background technique

[0002] Under the action of DC voltage, the carrier traps inside the DC cable insulation capture free electrons, resulting in the accumulation of space charges inside the insulation and changing the electrical conductivity of the insulation material. DC cable lines are inevitably affected by transient impulse voltages such as lightning waves and operating waves during operation. The existence of space charges promotes the formation and development of discharge channels in the insulating medium under transient impulse voltages. However, during the action time of the lightning shock wave whose polarity is opposite to that of the DC voltage, the polarity of the space charge in the cable insulation material ...

Examples

Embodiment approach

[0132] The embodiment of the present invention provides a parameter determination method for an 800kV UHV DC cable superimposed impact test device, and the specific steps include:

[0133] 1) Determine some parameters of the DC superimposed impulse voltage test device

[0134] The parameters of each equipment in the DC superimposed impulse voltage test device are as follows: C 1 0.182μF; charging voltage U Imp is 1946kV; R f 17.78Ω; R t 649Ω; C s 2000pF; C cd 400pF; C 0 To be determined; C t To be determined; R rcd 1010.77MΩ; C rcd is 293.1pF; R d To be determined; C d 0.05μF; r d is 20.85kΩ; U 0 800kV.

[0135] 2) Determine the parameters of the cable sample

[0136] The relative dielectric constant ε of 800kV UHV DC cable is 2.47, and the dielectric constant ε in vacuum 0 8.85×10 -12 F / m, the outer diameter of the insulating layer d o is 144mm; the inner diameter of the insulating layer is d i is 64mm; cable sample length L is 150m; cable insulation layer r...

technical field

[0001] The invention relates to the technical field of insulation performance detection of power cable equipment, and more specifically, to a method and system for determining parameters of a UHV DC cable superimposed impact test device. Background technique

[0002] Under the action of DC voltage, the carrier traps inside the DC cable insulation capture free electrons, resulting in the accumulation of space charges inside the insulation and changing the electrical conductivity of the insulation material. DC cable lines are inevitably affected by transient impulse voltages such as lightning waves and operating waves during operation. The existence of space charges promotes the formation and development of discharge channels in the insulating medium under transient impulse voltages. However, during the action time of the lightning shock wave whose polarity is opposite to that of the DC voltage, the polarity of the space charge in the cable insulation material ...

Examples

Embodiment approach

[0132] The embodiment of the present invention provides a parameter determination method for an 800kV UHV DC cable superimposed impact test device, and the specific steps include:

[0133] 1) Determine some parameters of the DC superimposed impulse voltage test device

[0134] The parameters of each equipment in the DC superimposed impulse voltage test device are as follows: C 1 0.182μF; charging voltage U Imp is 1946kV; R f 17.78Ω; R t 649Ω; C s 2000pF; C cd 400pF; C 0 To be determined; C t To be determined; R rcd 1010.77MΩ; C rcd is 293.1pF; R d To be determined; C d 0.05μF; r d is 20.85kΩ; U 0 800kV.

[0135] 2) Determine the parameters of the cable sample

[0136] The relative dielectric constant ε of 800kV UHV DC cable is 2.47, and the dielectric constant ε in vacuum 0 8.85×10 -12 F / m, the outer diameter of the insulating layer d o is 144mm; the inner diameter of the insulating layer is d i is 64mm; cable sample length L is 150m; cable insulation layer r...

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