The failure current test apparatus for high voltage DC transmission converter valve that surge voltage is compound
Technical field
The present invention relates to a kind of failure current test apparatus for high voltage DC transmission converter valve, specifically relate to the compound failure current test apparatus for high voltage DC transmission converter valve of surge voltage.
Background technology
Increase along with capacity during power semiconductor, the high-pressure series semiconductor device art of take is developed rapidly as basic high voltage dc transmission technology, in electric system, be used widely, the reliability of its core component---high-power high voltage series thyristor valve becomes the key of security of system.And fault current test is to be related to high voltage tandem thyristor valve Design and manufacture level, improve the important tests means of its reliability.Its fundamental purpose is that the design that checking valve bears maximum current, voltage and temperature stress effect that short-circuit current causes is correct.The world generally adopts compound experiment method by many covers power-supply system, to be respectively converter valve at present provides the forward and reverse high pressure after heating current, fault current and fault.Fault current test comprises following two pilot projects:
A) single ripple of follow-up locking time fault current is tested---and suppress single ripple time fault current of a maximum amplitude, from maximum temperature, start, the reverse and forward voltage that and then locking occurs, comprises the superpotential that any removal of load causes; (with reference to test waveform shown in figure 2)
B) without many ripples time fault current of follow-up locking, test---testing under identical condition with Dan Boci, until before circuit breaker trip, many ripples time fault current that exists, but no longer apply forward voltage.(with reference to test waveform shown in figure 3)
Current hookup high voltage appearance source generally consists of L, C oscillatory circuit, the high voltage waveform Symmetrical that it provides.So for time fault current test of single ripple, forward and reverse high pressure amplitude equal and opposite in direction that general synthetic test loop provides for test product after fault current extinguishes.And in actual condition, test product valve is after experience fault current, converter valve is first born reverse voltage, and then voltage rises until reach forward peak value, and the peak value of back voltage is less than peak forward voltage, and in this process, test product valve joint temperature reduces gradually.The reverse too high voltages that general synthetic test loop provides is very unfavorable to just standing the higher converter valve of fault current joint temperature, has the possibility of damaging test product.In addition, the peak forward voltage that in actual condition, converter valve is born is 5ms after its reverse voltage zero passage constantly, for general synthetic test loop, for reaching this, requires necessary modification circuits relevant parameters, not only increases investment but also make troubles to test operation.
Summary of the invention
In order to solve defect of the prior art, the object of the invention is to propose the compound failure current test apparatus for high voltage DC transmission converter valve of surge voltage, this device adopts the voltage of Symmetrical mutually compound to form positive and negative asymmetric forward and reverse high pressure with surge voltage, and surge voltage applies can be chosen arbitrarily constantly, amplitude is adjustable continuously as required, test method is flexible, safety, can fully meet the testing requirements of single ripple time fault current and three ripples time fault current.
For achieving the above object, the present invention adopts following proposal:
The failure current test apparatus for high voltage DC transmission converter valve that surge voltage is compound, described device comprises DC current source, auxiliary valve V, test product valve Vt, fault current source and impulse voltage generator; Its improvements are: described impulse voltage generator, fault current source are connected in parallel on test product valve Vt two ends; Described test product valve Vt series connection auxiliary valve V forms the brachium pontis of 6 fluctuation bridge rectifier B6 in DC current source; Described test product valve Vt negativing ending grounding; Described DC current source comprises strong current transformer T, isolating switch, disconnector, current limiting reactor, reactor Lh and L1 and 6 fluctuation bridge rectifier B6; Described strong current transformer T, isolating switch, disconnector and current limiting reactor are connected successively; Reactor Lh and L1 that the output termination of described 6 fluctuation bridge rectifier B6 is connected successively.
A kind of preferred technical scheme provided by the invention is: described fault current source comprises charging device, discharging capacitor C1, C2 and C3, electric discharge reactor L1, isolation valve V1, V2 and V3, isolation switch S1, S2 and S3; Described charging device comprises AC power T3, fairing T2 and resistance R; After wherein said AC power fairing in parallel, connect with resistance R; One end of described electric discharge reactor L1 is connected with the negative electrode of auxiliary valve V, and the other end of described electric discharge reactor L1 is connected with the negative electrode of isolation valve V3 with isolation valve V1, isolation valve V2 respectively; The anode of described isolation valve V1 is connected with one end of discharging capacitor C1, the other end ground connection of described discharging capacitor C1; The anode of described isolation valve V2 is connected with one end of discharging capacitor C2, the other end ground connection of described discharging capacitor C2; The anode of described isolation valve V3 is connected with one end of discharging capacitor C3, the other end ground connection of described discharging capacitor C3; One end of described isolation switch S1 is connected with the common port between isolation valve V1 and discharging capacitor C1, and the other end of described isolation switch S1 is connected with one end of resistance R; One end of described isolation switch S2 is connected with the common port between isolation valve V2 and discharging capacitor C2, and the other end of described isolation switch S2 is connected with one end of resistance R; One end of described isolation switch S3 is connected with the common port between isolation valve V3 and discharging capacitor C3, and the other end of described isolation switch S3 is connected with one end of resistance R; The other end of described resistance R is connected with the output terminal of described AC power T3.
The preferred technical scheme of the second provided by the invention is: described impulse voltage generator comprises power supply T1, capacitor C 4, resistance R 1 and ignition pill gap Q1 and Q2; Described power supply T1, capacitor C 4 and resistance R 1 are in parallel successively; Described power supply T1 is connected with ignition pill gap Q1 with ground respectively with capacitor C 4 two ends; Described resistance R 1 two ends are connected with Q2 with ignition pill gap Q1 with ground respectively; Described ignition pill gap Q2 connects with electric discharge reactor L1.
The third preferred technical scheme provided by the invention is: isolated DC current source after the heating current of described auxiliary valve V in test product extinguishes.
The 4th kind of preferred technical scheme provided by the invention is: described fault current source provides fault current to test product valve Vt after test product valve Vt is heated to certain junction temperature, in time fault current test of single ripple, also to test product valve Vt, provides reverse voltage and the part forward voltage after fault current.
The 5th kind of preferred technical scheme provided by the invention is: described impulse voltage generator provides surge voltage to test product valve Vt, in time fault current test of single ripple, this voltage is forward impact voltage, the forward voltage of the mutually compound composition test product valve of forward voltage providing with fault current source; In time fault current test of three ripples, this surge voltage is oppositely, after-applied on test product valve at second failure electric current.
Compared with prior art, beneficial effect of the present invention is:
1, the hookup of test unit provided by the invention is relatively simple, builds simply low cost;
2, test unit provided by the invention has saved the high voltage source in generic failure current testing, by surge generator, is substituted, and has solved the problem of the forward and reverse voltage symmetry of test product valve, makes to test safer;
3, in test unit provided by the invention because surge voltage applies constantly, voltage magnitude is adjustable continuously, can be that test product voltage accurately reaches required voltage peak value in the set moment, test method is flexible, applicable to the converter valve of different DC engineerings.
Accompanying drawing explanation
Fig. 1 is the mutually compound failure current test apparatus for high voltage DC transmission converter valve of surge voltage;
Fig. 2 is single ripple time fault current test waveform figure of follow-up locking;
Fig. 3 is the many ripples time fault current test waveform figure without follow-up locking;
Wherein: Vt-test product valve, B6-6 fluctuation bridge rectifier, V-auxiliary valve, C1, C2, C3-discharging capacitor, the L1-reactor that discharges, V1, V2, V3-isolation valve, T1-power supply, C4-electric capacity, R1-resistance, Q1, Q2-ball gap, R-resistance, S1, S2, S3 are isolation switch.
Embodiment
Below in conjunction with accompanying drawing, the compound failure current test apparatus for high voltage DC transmission converter valve of surge voltage provided by the invention is described in further detail.
Be the compound failure current test apparatus for high voltage DC transmission converter valve of surge voltage as shown in Figure 1, this device comprises DC current source, auxiliary valve V, test product valve Vt, fault current source and impulse voltage generator; Impulse voltage generator, fault current source are connected in parallel on test product valve Vt two ends; Test product valve Vt series connection auxiliary valve V forms the brachium pontis of 6 fluctuation bridge rectifier B6 in DC current source; Test product valve Vt negativing ending grounding.
DC current source comprises strong current transformer T, isolating switch, disconnector, current limiting reactor, reactor Lh and L2 and 6 fluctuation bridge rectifier B6; Strong current transformer T, isolating switch, disconnector and current limiting reactor are connected successively; Reactor Lh and L2 that the output termination of 6 fluctuation bridge rectifier B6 is connected successively.
Fault current source comprises charging device, discharging capacitor C1, C2 and C3, electric discharge reactor L1, isolation valve V1, V2 and V3, isolation switch S1, S2 and S3; Charging device comprises AC power T3, fairing T2 and resistance R; After wherein said AC power fairing in parallel, connect with resistance R; One end of described electric discharge reactor L1 is connected with the negative electrode of auxiliary valve V, and the other end of described electric discharge reactor L1 is connected with the negative electrode of isolation valve V3 with isolation valve V1, isolation valve V2 respectively; The anode of described isolation valve V1 is connected with one end of discharging capacitor C1, the other end ground connection of described discharging capacitor C1; The anode of described isolation valve V2 is connected with one end of discharging capacitor C2, the other end ground connection of described discharging capacitor C2; The anode of described isolation valve V3 is connected with one end of discharging capacitor C3, the other end ground connection of described discharging capacitor C3; One end of described isolation switch S1 is connected with the common port between isolation valve V1 and discharging capacitor C1, and the other end of described isolation switch S1 is connected with one end of resistance R; One end of described isolation switch S2 is connected with the common port between isolation valve V2 and discharging capacitor C2, and the other end of described isolation switch S2 is connected with one end of resistance R; One end of described isolation switch S3 is connected with the common port between isolation valve V3 and discharging capacitor C3, and the other end of described isolation switch S3 is connected with one end of resistance R; The other end of described resistance R is connected with the output terminal of described AC power T3.
Impulse voltage generator comprises power supply T1, capacitor C 4, resistance R 1 and ignition pill gap Q1 and Q2; Described power supply T1, capacitor C 4 and resistance R 1 are in parallel successively; Power supply T1 is connected with ignition pill gap Q1 with ground respectively with capacitor C 4 two ends; Resistance R 1 two ends are connected with Q2 with ignition pill gap Q1 with ground respectively; Ignition pill gap Q2 connects with electric discharge reactor L1.
DC current source first in test provides the heating current before fault current for test product valve, makes its joint temperature reach a base value; After the heating current of auxiliary valve in test product valve extinguishes, DC current source is isolated; Fault current source provides fault current to test product valve after test product valve is heated to certain joint temperature, in time fault current test of single ripple, also to test product, provides reverse voltage and the part forward voltage after fault current; Impulse voltage generator provides surge voltage to test product valve, and in the test of single ripple time fault current, this voltage is forward impact voltage, the forward voltage of the mutually compound composition test product valve of forward voltage providing with fault current source, as shown in Figure 2; In time fault current test of three ripples, this surge voltage is oppositely, after-applied on test product valve, as shown in Figure 3 at second failure electric current.
The failure current test apparatus for high voltage DC transmission converter valve that surge voltage provided by the invention is compound, this device adopts the voltage of Symmetrical mutually compound to form positive and negative asymmetric forward and reverse high pressure with surge voltage, and surge voltage applies can be chosen arbitrarily constantly, amplitude is adjustable continuously as required, test method is flexible, safety, can fully meet the testing requirements of single ripple time fault current and three ripples time fault current.
Finally should be noted that: in conjunction with above-described embodiment, illustrate that technical scheme of the present invention is not intended to limit.Those of ordinary skill in the field are to be understood that: those skilled in the art can modify or be equal to replacement the specific embodiment of the present invention, but among the claim protection domain that these modifications or change are all awaited the reply in application.