Electric reactor turn-to-turn short circuit fault protection method and device

An inter-turn short-circuit fault, reactor technology, applied in circuit devices, emergency protection circuit devices, emergency protection device parts and other directions, can solve the problems of reactor winding damage, loss of maintenance value, and small current variation.

CN112688273AActive Publication Date: 2021-04-20GUODIAN NANJING AUTOMATION
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Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
Publication Date
2021-04-20

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Abstract

The invention discloses an electric reactor turn-to-turn short circuit fault protection method and device applied to a brake energy capacitor energy storage device, and belongs to the technical field of electric reactor protection. A circuit breaker tripping signal is output and uploaded to a man-machine display interface to give an alarm by taking the characteristics that the operation efficiency of a brake energy capacitor energy storage device is reduced due to instantaneous consumption of a large amount of energy in a turn-to-turn short-circuit fault of a reactor and the equivalent direct-current resistance value of the reactor is changed as double judgment conditions. Therefore, the short-circuit fault of the reactor can be effectively protected. According to the invention, extra equipment is not required to be added, and only components of the brake energy capacitor energy storage device are utilized to acquire signals, perform logical operation and trigger protection, so that the equipment cost is saved, and the rapidity and reliability of turn-to-turn fault protection of the reactor are improved.
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Description

technical field

[0001] The invention belongs to the technical field of electric equipment fault protection, and in particular relates to a method for protecting a reactor from a turn-to-turn short-circuit fault, and also relates to a reactor to a turn-to-turn short-circuit fault protection device. Background technique

[0002] Dry-type reactors have been widely used in large-scale power equipment, but during long-term operation, there will be a problem of aging of the insulating medium. If there are external factors stimulating, local cracks may appear on the surface of the reactor where the insulating layer is relatively weak. Discharge, damage the inter-turn insulation, and gradually develop into a short circuit fault. The short-circuit current causes the temperature of the faulty part to rise sharply, which further leads to the destruction of the insulation between adjacent turns, and finally causes the reactor to overheat locally or even catch fire, endangering the opera...

Examples

Embodiment 1

[0048] The invention relates to a reactor turn-to-turn short-circuit fault protection method, which is suitable for the inter-turn short-circuit fault protection of an internal smoothing reactor in a DC 750V / 1500V urban rail transit braking energy capacitive energy storage device. Its structural diagram is as figure 1 As shown, in the main circuit of the braking energy capacitor energy storage device, a voltage sensor LV1 and a current sensor CT1 are installed on the DC750V network side, and a voltage sensor LV2 and a current sensor CT2 are installed on the capacitor side to collect voltage and current respectively. The front end of the DC reactor L is connected to the IGBT module, and the rear end is connected to the capacitor group C2. The DC grid side circuit breaker QF is used to protect the main circuit. The sampling board in the control circuit is used to convert analog and digital quantities, the IO signal board is used to output and input switching values, the control...

Embodiment 2

[0082] A reactor turn-to-turn short-circuit fault protection device of the present invention is characterized in that it comprises: a sampling board, an IO signal board and a control unit;

[0083] Sampling board, used to collect grid-side voltage, capacitor-side voltage, grid-side current and capacitor-side current;

[0084] The control unit is used to judge whether the first judging condition and the second judging condition are satisfied at the same time according to the grid-side voltage, the capacitor-side voltage, the grid-side current, and the capacitor-side current,

[0085] The first judgment condition:

[0086] Calculate the equivalent DC resistance of the reactor;

[0087] The error between the equivalent DC resistance of the reactor and the rated equivalent DC resistance exceeds the first preset threshold;

[0088] The second judgment condition:

[0089] Calculate the operating efficiency of the braking energy capacitor energy storage device;

[0090] The diffe...