Summary of the invention
In order to overcome the above-mentioned defective in the middle of the prior art; the objective of the invention is characteristics in conjunction with power electronic equipment; with the rapidity of breakdown diode BOD (BOD:Break Over Diode) protection action and the high-power thyristor valve big advantages of energy of releasing; a kind of frequent movement that is suitable for is provided; the operation voltage accuracy; stability is high; operation voltage is easy to adjust; protection is swift in motion; residual voltage is little; the novel overvoltage protection that the energy of releasing is big: breakdown diode BOD triggers the thyristor-type overvoltage protection; thereby realize that a kind of operation voltage stability is high, the novel protected means that discharge capacity is big.
Breakdown diode BOD triggers thyristor valve over-voltage protector and does not see identical or similar techniques at home, outward as yet.
The present invention solves the technical scheme that its technical problem takes: a kind of breakdown diode BOD triggers breakdown diode that the thyristor-type overvoltage protection triggers thyristor unit or a plurality of series connection by a breakdown diode and triggers the thyristor unit and constitute; be connected to breakdown diode BOD between gate circuit transistor gate and the anode; breakdown diode BOD is transformed into on-state when the forward voltage between thyristor negative electrode and the anode surpasses a certain particular value, triggers thyristor by a kind of rapid short circuit effect.The damping absorption circuit that first resistance also in parallel and first capacitances in series are formed between thyristor negative electrode and the anode, breakdown diode BOD trigger the series thyristor unit by protection damping resistance ground connection.
Anode one end of breakdown diode is connected with the anode of thyristor Vp with current-limiting resistance series connection back, negative electrode one end of breakdown diode links to each other with the gate pole of diode with thyristor Vp by the voltage stabilizing didoe of series connection, and negative electrode one end of breakdown diode also links to each other with the negative electrode of thyristor Vp with the second electric capacity parallel branch by second resistance simultaneously.
The operation voltage of breakdown diode BOD can determine superpotential protection level, and the damping absorption circuit absorbs the shutoff overshoot of thyristor, also plays the effect that slows down the overvoltage wave head.The protection damping resistance then plays electric current, the catabiotic effect of suppressing, and the selection of its resistance value has also determined the size of protection action residual voltage simultaneously.
Owing to adopted above-mentioned technical scheme, the beneficial effect that the present invention has is: the operation voltage of breakdown diode BOD can determine superpotential protection level, can determine superpotential protection level according to the voltage of breakdown diode BOD.Damping absorption circuit in the breakdown diode triggering thyristor unit not only can absorb the shutoff overshoot of thyristor, also plays the effect that slows down the overvoltage wave head.The protection damping resistance that breakdown diode triggers thyristor unit serial connection then can play electric current, the catabiotic effect of suppressing, and the selection of its resistance value has also determined the size of protection action residual voltage simultaneously, and the through-current capability of this protective device is also very big.Most of energy of overvoltage shock wave all consumes on the protection damping resistance, and thyristor is the conduction loss of self.
Bear the superpotential energy of releasing by lower-cost resistance, and the high thyristor of control precision is responsible for the voltage protection action, compares with the over-voltage protection method that adopts lightning arrester, the advantage of the technical program is tangible:
The puncture operation voltage dispersiveness of breakdown diode BOD is little, and action error generally has only about 2%, makes protected mode of the present invention have good operation voltage stability;
The rapidity of breakdown diode BOD action and thyristor conducting makes technical scheme of the present invention have the responsiveness of μ s level;
Because high-power thyristor serial connection technology, big discharge capacity thyristor manufacturing technology be maturation, therefore technical scheme of the present invention can be applied to the high-voltage great-current field;
The damping absorption circuit that the protection breakdown diode triggers the thyristor unit can play the purpose of alleviating the overvoltage wave head and suppressing temporary overvoltage;
Breakdown diode BOD trigger voltage, breakdown diode trigger the serial number of thyristor unit and big or small Turin of damping resistance is lived adjustable, be thyristor working voltage, protection operation voltage, residual voltage and fault current etc. is all adjustable, so this protective device has good adaptability and adjustability;
Therefore the protection residual voltage of this protective device can be transferred to very low by the decision of protection damping resistance.
Embodiment
The present invention is further described below in conjunction with drawings and Examples.
Referring to accompanying drawing 1; breakdown diode BOD of the present invention triggers the thyristor-type overvoltage protection and is made of the breakdown diode triggering thyristor unit that a breakdown diode triggers thyristor unit or a plurality of series connection; be connected to breakdown diode BOD between thyristor Vp gate pole and the anode; breakdown diode BOD is transformed into on-state when the forward voltage between thyristor negative electrode and the anode surpasses a certain particular value, triggers thyristor by a kind of rapid short circuit effect.The operation voltage of breakdown diode BOD can determine superpotential protection level.Voltage according to breakdown diode BOD can determine superpotential protection level.
Anode one end of breakdown diode is connected with the anode of thyristor Vp with current-limiting resistance series connection back, negative electrode one end of breakdown diode connects the anode of voltage stabilizing didoe, the negative electrode of voltage stabilizing didoe links to each other with the anode of diode, the negative electrode of diode links to each other with the gate pole of thyristor Vp, and negative electrode one end of breakdown diode also links to each other with the negative electrode of thyristor Vp with the second capacitor C parallel branch by second resistance R simultaneously.
Also and be connected to the damping absorption circuit that is composed in series by the first resistance R s and the first capacitor C s, this damping absorption circuit can absorb the shutoff overshoot of thyristor Vp, also plays the effect that slows down the overvoltage wave head between thyristor negative electrode and the anode.
Terminal breakdown diode BOD triggers the series thyristor unit by protection damping resistance Rp ground connection; this protection damping resistance Rp can play electric current, the catabiotic effect of suppressing; the selection of its resistance value has also determined the size of protection action residual voltage simultaneously, and the through-current capability of protective device is also very big.