The gate drive circuit of mesohigh power semiconductor convertor equipmentTechnical field
The utility model relates to a kind of mesohigh power semiconductor convertor equipment control technology, particularly relates to a kind of gate drive circuit of mesohigh power semiconductor convertor equipment.
Background technology
Mesohigh power semiconductor (such as thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor) convertor equipment, such as mesohigh thyristor alternating-current voltage adjusting device, mesohigh thyristor soft-starter or mesohigh thyristor rectifier contravariant equipment etc., all take microprocessor as the low-voltage system of core due to its automation control system, and thyristor is all in high voltage appearance circuit, so its phase-shifting trigger pulse, usually be all produce phase shifting control trigger impulse through Optical Fiber Transmission by Control System of Microcomputer, the signal of telecommunication is become again through opto-electronic conversion, be added between the gate pole of thyristor and negative electrode by semiconductor power amplification circuit, make IGBT group conducting.This one or two light signal become can control IGBT group conducting circuit (gate drive circuit) although voltage is not high, but between tens volts to three, 40 volts, but it is in high voltage environment, its control signal comes from optical fiber, can meet the insulation request in high pressure forceful electric power loop and low pressure vulnerabilities scan loop.The isolating problem in the high pressure forceful electric power loop that another will solve and low pressure vulnerabilities scan loop is its power supply, and also namely circuits for triggering power supply (triggering voltage) also will meet the insulation request of high-low voltage.
Existing solution has following three kinds:
1, so-called " self-powered thyristor gate drive circuit ".See Fig. 1, Fig. 1 is the phase in a 6KV thyristor solid-state soft starter, power to thyristor gate drive circuit by the other resitstance voltage divider in parallel of the thyristor in 6KV forceful electric power loop takes out voltage, and its phase-shift pulse control signal is sent here by optical fiber, so thyristor gate drive circuit here and light-current system are isolated.But there is fatal shortcoming in this method: 1) power consumption is large.Simply calculate, if thyristor gate drive circuit needs 20V 10W power, for the 6KV circuit of three Thyristors in series, each divider resistance will increase the power consumption of 2KW.2) check very inconvenient.Thyristor gate drive circuit is because under being in High Voltage electrical environment, and if after high-voltage power voltage reduces, this circuit just can not work, so can not simply replace high pressure to carry out work with low pressure 380V power supply, so be provided with the attaching plug for checkout facility on the board all in addition.3) because this gate drive circuit after the voltage drop of thyristor two end is with regard to cisco unity malfunction, so also need to provide other independent power supply under a few thing state.Such as adopting can be specially dated on the mesohigh thyristor solid-state soft starter operation instructions of this gate drive circuit: " noting: if use pump to control or stop controlling, gate-drive plate uses independent current source power supply board to power continuously ".
So newly-designed product does not generally adopt the 1st kind of method, there are two kinds of circuit structures improved below at present.
2, the thyristor gate drive circuit of power current transformer for supplying power is adopted.In a high-pressure thyristor device, a such as 6KV thyristor soft-starter, each thyristor gate drive circuit is powered by the secondary winding of an independently current transformer, the secondary current of instrument transformer then comes from a high-tension cable through them, and high-tension cable two end is received on a low voltage heavy current transformer.So, this root high-tension cable is just shouldered the buffer action of low voltage heavy current transformer from the current transformer winding in the gate drive circuit be under different level high; Each current transformer has suitable distance simultaneously, is also isolation mutually between them, thus ensures that each gate drive circuit being in different voltage levvl can be mutually isolated.The shortcoming of which is that the elementary exciting current of instrument transformer is larger, controls power ratio comparatively large, and the high-tension electricity cable core through each instrument transformer is also relatively thicker, and each current transformer volume is larger.
3, the semiconductor power device gate drive circuit of high-voltage pulse power source transformer-supplied is adopted.In mesohigh power semiconductor (such as thyristor) convertor equipment, a such as 10KV thyristor soft-starter, each thyristor gate drive circuit is powered by each auxiliary winding of several high-voltage pulse power source transformer, and a high-voltage pulse power source transformer is powered to four thyristor gate drive circuit.Because thyristor gate drive circuit is in the high voltage environment of 10KV, and also there is very high voltage between each thyristor, so very high to the insulating requirements of high-voltage pulse power source transformer, each winding all will examine it to insulate by 10KV operating voltage, and their output lead also uses the high-tension bus-bar of silicon rubber insulation.If each such high-voltage pulse power source transformer is with too many thyristor, volume will be very huge.
Summary of the invention
The purpose of this utility model is the gate drive circuit providing a kind of mesohigh power semiconductor convertor equipment, and this gate drive circuit can carry out trigging control to the power semiconductor be in convertor equipment under each different level high (such as thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor) gate pole.
In order to realize above-mentioned technical purpose, the utility model adopts following technical scheme:
A gate drive circuit for mesohigh power semiconductor convertor equipment, comprises low pressure intermediate frequency power supply, intermediate frequency step-down transformer, high-tension cable, electric current of intermediate frequency instrument transformer, current rectifying and wave filtering circuit, gate electrode drive signals optical fiber input circuit, pulse power amplifier circuit;
Described low pressure intermediate frequency power supply is connected on universal industrial power supply, low pressure intermediate frequency power supply exports and connects intermediate frequency step-down transformer input (elementary) end, intermediate frequency step-down transformer exports (secondary) terminated high voltage electrical cables, high-tension cable is set with multiple electric current of intermediate frequency instrument transformer, electric current of intermediate frequency instrument transformer exports and connects current rectifying and wave filtering circuit, current rectifying and wave filtering circuit exports and connects pulse power amplifier circuit input, pulse power amplifier circuit input connects gate electrode drive signals optical fiber input circuit simultaneously, and pulse power amplifier circuit exports the gate pole connecing mesohigh power semiconductor.
Described intermediate frequency is 400 to 1000Hz.
Described mesohigh power semiconductor is thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor.
Described high-tension cable is high voltage-small current single-core cable.
Described each electric current of intermediate frequency instrument transformer is mutually isolated.
The gate drive circuit of the utility model mesohigh power semiconductor convertor equipment makes the gate drive circuit energy being in different voltage levvl mutually isolated, and isolates with low pressure microcomputer control circuit.Gate drive circuit of the present utility model can carry out trigging control to the power semiconductor be in convertor equipment under each different level high (such as thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor) gate pole.Compared with the scheme such as employing power current transformer for supplying power, power consumption and the components and parts volume of whole gate drive circuit all greatly reduce.
Accompanying drawing explanation
Fig. 1 is the self-powered gate drive circuit electrical schematic diagram of a phase thyristor in 6KV thyristor soft-starter;
Fig. 2 is the gate drive circuit electrical schematic diagram of the utility model mesohigh power semiconductor convertor equipment.
In figure: 1 low pressure intermediate frequency power supply, 2 intermediate frequency step-down transformers, 3 high-tension cables (single core), 4 electric current of intermediate frequency instrument transformers, 5 current rectifying and wave filtering circuits, 6 gate electrode drive signals optical fiber input circuits, 7 pulse power amplifier circuits.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is described in further detail.
See Fig. 2, a gate drive circuit for mesohigh power semiconductor convertor equipment, comprises low pressure intermediate frequency power supply 1, intermediate frequency step-down transformer 2, high-tension cable 3, electric current of intermediate frequency instrument transformer 4, current rectifying and wave filtering circuit 5, gate electrode drive signals optical fiber input circuit 6, pulse power amplifier circuit 7, described low pressure intermediate frequency power supply 1 is connected on universal industrial power supply, low pressure intermediate frequency power supply 1 output connects intermediate frequency step-down transformer 2 and inputs (elementary) end, intermediate frequency step-down transformer 2 exports (secondary) terminated high voltage electrical cables 3, high-tension cable 3 is set with multiple electric current of intermediate frequency instrument transformer 4, electric current of intermediate frequency instrument transformer 4 exports and connects current rectifying and wave filtering circuit 5, current rectifying and wave filtering circuit 5 exports and connects pulse power amplifier circuit 7 input, pulse power amplifier circuit 7 input connects gate electrode drive signals optical fiber input circuit 6 simultaneously, pulse power amplifier circuit 7 exports the gate pole connecing mesohigh power semiconductor.Described universal industrial power supply is the single-phase 220V of power frequency; Intermediate frequency is 400 to 1000Hz; Mesohigh power semiconductor is thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor; High-tension cable 3 is high voltage-small current single-core cable; Each electric current of intermediate frequency instrument transformer 4 is mutually isolated.
The gate drive circuit of the utility model mesohigh power semiconductor convertor equipment is powered by the electric current of intermediate frequency instrument transformer 4 that each locus be enclosed within a high voltage-small current single-core cable is mutually isolated, electric current of intermediate frequency instrument transformer 4 is low voltage mutual inductor, therefore the power supply provided by each instrument transformer secondary is mutually isolated, and mutually isolated with its primary current, adapt with the electric pressure of mesohigh semiconductor variable flow device withstand voltage can be born.Because electric current of intermediate frequency instrument transformer 4 armature winding is in low voltage control system, and its body and secondary winding thereof are in high-voltage power convertor circuit system, utilize high-tension cable 3 to realize the isolation of electric current of intermediate frequency instrument transformer 4 primary and secondary winding here.
High-tension cable 3 in the utility model is high voltage-small current single-core cable, and the electric current flow through in high-tension cable is small area analysis.High-tension cable is provided through a step-down transformer 2 by a low pressure intermediate frequency power supply 1.This low pressure intermediate frequency power supply 1 is connected on public control power supply, i.e. the single-phase 220V of power frequency.
Described electric current of intermediate frequency instrument transformer 4 is operated in 400 ~ 1000Hz intermediate frequency, so small volume, its current rectifying and wave filtering circuit is also smaller.
Described gate pole control signal comes from optical fiber, after light-to-current inversion, then is applied to through pulse power amplifier circuit 7 on the gate pole of power semiconductor (such as thyristor, bidirectional thyristor, gate level turn-off thyristor, integrated gate commutated thyristor).
The gate drive circuit of the utility model mesohigh power semiconductor convertor equipment is applicable to the mesohigh convertor equipment of mesohigh power semiconductor composition, applies trigger impulse control the power device be under each different high-pressure horizontal.This power device is thyristor or multiple types seemingly semiconductor power device, and power device can have multiple.
These are only preferred embodiment of the present utility model; be not intended to limit protection range of the present utility model; therefore, all do within spirit of the present utility model and principle any amendment, equivalent replacement, improvement etc., all should be included within protection range of the present utility model.