As everyone knows, connecting technology in parallel has already become key technology of realizing distributed power system of high-power, but because every module characteristic of connecting the power in parallel is not totally unanimous, the module of the output with high voltage may be born and supported more, but some module may lighter by year, even empty load run, result lead to the fact share electric current many module heat stress to be loud, have reduced the working dependability of the whole power. With the development of electronic system, the requirements for power dependability, efficiency and power density are higher and higher, so it is necessary to adopt a kind of effective flowing and controlling the scheme, guarantee the output electric current of the whole power system is shared equally according to the output ability of each unit module, in this way, not only can give full play to the output ability of the power module of unit guarantee the working dependability of each unit power, but also can.
Against become main circuit for hand in and frank – hand in voltage type, it commutates sides to be controllable type as single-phase diode. This way not only controls simply but also have a higher power factor systematically. In order to reduce the device volume, reduce the harmonic wave, improve electric current wave form quality. The power component adopts module PM20CSJ060 of the third generation of intellectual power of Mitsubishi Electric Company of the high switch frequency against turning into. Module this unify encapsulation for six, inside the intersection of three-phase and bridge the intersection of circuit and structure, inside integrate at a high speed low the intersection of IGBT and chip of consumption and drive, protect the circuit. In addition, this module also integrates overheatedly and owes and presses and locks and protects the circuit, make the dependability of the system further improved . Space of six routes vector signal SVPWM that LF2407 chip outputs on the control circuit is realized that isolates IPM to drive by the photosensitive resister 6N136, and then commutate the direct current after straining the wave and press and go against to turn into necessary high-frequency alternating current and drive the compressor of air conditioner of permanent magnetism.
There is electric current that measures the circuit in the system, adopt the sensor of Hall’s electric current to measure the magneto A, C two phase forever, utilize, sample resistance and then and many stages transport show, deal with for simulation voltage signal that change among 0- 5V the intersection of electric current and signal, the pin links with integrating outside A/D converter in LF2407. Because of not having initial position where position sensor technology can’t know the rotor, the magneto works under having position sensor state after only starting too forever, so realize the detection of the initial position of the rotor with the photoelectricity type rotation encoder. Realization comes by the incident managing device of LF2407 in other protection circuit, once break down systematically, the break procedure solidifying in slice exports cutting off systematic SVPWM automatically, until the trouble disappears and resets systematically.
This text foundation permanent magnetism synchronous motor vector controls the requirements of principle and frequency conversion air conditioner, have developed a set of brand-new frequency conversion air conditioner control systems based on DSP. SVPWM control signal produced with six PWM complete comparators of LF2407 can realize that control the frequency conversion of the synchronous motor of permanent magnetism. This air conditioner of control systems have fully utilized superstrong real-time computing capability and some integrated devices of LF2407, make the whole system simple in construction, products development period is short, highly reliable.