Novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device

Abstract

The invention discloses a novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device, and belongs to the field of arc elimination and overvoltage protection. The novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device comprises high-voltage current-limiting fuses, a zinc oxide nonlinear resistor, an overvoltage protection controller, a harmonic oscillation capacitor, a harmonic oscillation resistor, a harmonic elimination controller, a voltage transformer, a microcomputer, an arc elimination controller and a linear arc elimination resistor. The high-voltage current-limiting fuses, the zinc oxide nonlinear resistor, the overvoltage protection controller, the harmonic oscillation capacitor, the harmonic oscillation resistor, the harmonic elimination controller, the voltage transformer, the microcomputer, the arc elimination controller and the linear arc elimination resistor are arranged in the novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device. The novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device is novel in design and convenient to use. The novel convenient and practical arc and harmonic elimination and overvoltage protection three-purpose device is provided with an arc and harmonic elimination system and an overvoltage protection system, so that the arc elimination and overvoltage protection requirements are met.

Description

【Technical field】 [0001] The invention belongs to the field of arc suppression and overvoltage protection, and in particular relates to a novel, convenient and practical three-purpose device for arc suppression, harmonic elimination and overvoltage protection. 【Background technique】 [0002] At present, most of the power distribution systems below 35kV in my country adopt the neutral point indirect grounding system. When a single-phase grounding fault occurs in the neutral point indirect grounding system, the fault current is capacitive current, and if it exceeds a certain limit, it will be ignited on the ground Unstable arc, accompanied by electromagnetic oscillation in the transient process, can easily cause single-phase intermittent arc grounding overvoltage. Although the amplitude is not large, if it exists for a long time, it will cause harm to equipment with weak insulation strength, and then cause phase-to-phase short circuit and other more serious hazards. In addition,...

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Problems solved by technology

[0002] At present, most of the power distribution systems below 35kV in my country adopt the neutral point indirect grounding system. When a single-phase grounding fault occurs in the neutral point indirect grounding system, the fault current is capacitive current, and if it exceeds a certain limit, it will be ignited on the ground Unstable arc, accompanied by electromagnetic oscillation in the transient process, can easily cause single-phase intermittent arc grounding overvoltage. Although the amplitude is not large, if it exists for a long time, it will cause harm to equipment with weak insulation strength, and then cause phase-to-phase short circuit and other more serious hazards. In addition, overvoltage phenomena caused by resonance overvoltage, operating overvoltage and other reasons are also common in non-neutral point grounding systems. Once overvoltage occurs, electrical equipment will often be damaged or a large area will be damaged. The power outage accident is very harmful

[0003] In the neutral point indirect grounding system, the purpose of arc suppression is generally achieved by adding an arc suppression coil, that is, the neutral point is grounded through the arc suppression coil. When the system is single-phase grounded, the inductance generated by the arc suppression coil The current compensates the capacitive current at the fault point to reduce the residual current at the fault point, thereby achieving the function of arc extinguishing. However, due to the diversity of power grid operation modes and the randomness of the ground fault point, the arc suppression coil is used to compensate the capacitive current It has certain difficulties, and the arc suppressing coil only compensates for the power frequency current, and there is no effective way for the high frequency current. Due to the limitation of the recovery voltage of the arc track, it often breaks down when it reaches the highest value, which amplifies the overvoltage. coefficient, can not achieve the ideal effect, and the direct grounding method of the fault phase, because it cannot completely and accurately determine the fault phase, it is easy to cause the hazard of short circuit between phases; because it cannot consume the excess charge on the bus, once it exits, it is easy to cause PT ferromagnetic Resonance; such equipment shall not be used for circuits such as high-voltage motors with direct power supply

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