0 foreword
Mix to high pressure, high-power to satisfy wind-force to generate electricity the demand of high quality convertor, much n convertor develop attacks got paying close attention to extensively. After converter uses much n means, can go up in foundation of compression of groovy power parts of an apparatus, achieve tall voltage order and degree, obtain more degree (step) output voltage, make weaveform is close to sine more, harmonic content is little, voltage change ratio is small, obtain larger output size. Much n convertor is specific circuit develop attacks can divide it is 5 kinds: Interconnection of diode Qian bit-type, two-way switch, fly cross capacitance model, combination of two n convertor, cascade of single-phase H bridge etc. Among them bridge of single-phase cascade H with bit-type of diode midpoint Qian much n develop attacks the structure is simple, control is quick, be in in recent years high-power frequency control, all have more application without the respect such as regulated power supply of merit compensation, high-power; In PWM control method, research is more is specific harmonic eliminates SPWM of PWM modulation, much carrier wave modulation of modulation, SPWM of carrier wave phase shift and dimensional vector modulation.
Although develop of cascade H bridge much n attacks with diode midpoint Qian the application that 3 n develop attacks has matured quite, but when the n number that should need increases further, former need more independent direct current source, latter needs more Qian parts of an apparatus exists the problem that capacitance voltage balances, so, at present diode Qian many n is given priority to with 5 n with 3 n. Accordingly, cascade H bridge and diode Qian 3 n develop attacks to be united in wedlock, can use both dominant position, have different control method in the light of this kind of structure, if control of disappear harmonic SPWM, SVPWM is controlled,wait.
The article is aimed at diode Qian develop of bridge of H of 5 n cascade attacks, the control means that offerred SPWM of harmonic of a kind of disappear and SPWM of carrier wave phase shift to be united in wedlock, through using different and phasic trigonometry carrier wave, make diode Qian bridge of 5 n H can produce much n to output conveniently, it is OK to make 5 ns power unit at the same time conveniently cascade is together. Attacked to undertake initial exploration in the application in system of cable of wind of permanent magnetism straight drive to this kind of develop, use dynamo of synchronism of 18 photographs permanent magnetism to move photograph transformer diode of 12 pulse commutator Qian bridge of H of 5 n cascade, can raise output voltage and power social estate further, generate electricity for wind-force output need not the step-up transformer can merge into directly middling pressure electrified wire netting offerred farther possibility.

1 develop attacks structural analysis
Graph 1 it is the diode Qian that the article uses develop of bridge of H of 5 n cascade attacks to apply a principle mediumly to pursue in system of cable of wind of constant frequency of straight drive gearshift, pursue among them 1(a) is diagram of construction of system, graph 1(b) is diode Qian graph of principle of unit of power of bridge of 5 n H. Group of graph 1(a) apoplectic electric machinery procrastinates move dynamo of synchronism of polyphase permanent magnetism, dynamo of permanent magnetism synchronism is 18 photographs electric machinery, share winding of 6 groups of output, between every groups of winding phasic difference 20 ° , every groups of winding enter diode Qian respectively power is unit, share 6 power unit to form three-phase inverter, unit of every 2 power undertakes cascade comprises one photograph output, three-phase output merges into through filter wave inductance electrified wire netting. In graph 1(b) , the input is the winding of a group of three-phase of dynamo of permanent magnetism synchronism, move through 3 winding photograph transformer, move photograph transformer is DDY structure, v/LIT all over the ground than be 1:1: ° of?0 of hesitating of the bridle austral Bao of fat Su of bore with a reamer of  north Bi, get independent direct current source by commutate of commutator of 12 pulse diode, shed side capacitance to be electroanalysised by two continuously among them capacitance series connection is formed, the midpoint of capacitance regards diode as Qian the midpoint of power circuit, and join with the midpoint of commutator of diode of two 6 pulse, dc passes diode Qian bridge of 5 n H undertakes inversion, output single-phase alternating current. By power unit 1, 2, 3 part and 4, 5, 6 cascade comprise three-phase output.
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