| With the development of people's living level, the required quantity of air-conditions is increasing. Because of the excellent performance and the energy saving, the fuzzy-control inverter air-condition becomes the main leading product of most air-condition manufacturer. The fuzzy-control technology is more and more valuable for each factory.The advantage of fuzzy-control inverter air-condition lies on the high efficiency, high precision of temperature control, low startup current and low noise. Furthermore, using brushless DC motor as the compressor can get high efficiency and long life span.The paper takes hardware design and software design into account to make the control system of the outdoor unit and indoor unit of the fuzzy-control inverter air-condition. According to the DC inverter air-condition in the market, this paper works out its own feature index and efficiency index, and also design the whole scheme of the air-condition system.In order to make the outdoor control system of the air-condition, which always works outdoors, more compact, high efficiency and high reliability, the controller is made up of IPM and microcomputer. In the system, 1PM works as the inverter. CPU of the outdoor unit independently controls the work of the compressor, the temperature sampling circuit, the driver of A and B throttle, the timing of outdoor fan, the driver of 4-way valve, the voltage and current sampling circuit, the communication between the indoor unit and the outdoor unit, and so on. According to the brushless DC compressor, the paper chooses the Motorola CPU. M68HC908MR24. which has PWM module, can also insert the dead-time automatically, and has four capture interrupts which can be used to capture the signal of position of the rotor. During the experiments, the compressor works smoothly, and has a wide speed span.The frame of the indoor unit is simpler than the outdoor unit, it mainly controls the indoor fan. the communication with the outdoor unit, and the movement of the louver and the flap. This paper uses Motorola CPU M68HC908GP32 and TOSHIBA CPU TMP87C846 to design two control systems of the indoor unit, and separately to control the DC indoor fan and AC indoor fan. The working condition of the communicating circuit has a great effect on the performance of the air-condition. There are many signals that need to be translated between the outdoor unit and indoor unit. The control system requires that the communication circuit works stably. Through comparing, the paper finally chooses the circuit that the chopper is based onthe AC source line. The control software also can filtrate the interference and get a high anti-jamming performance. Through both hardware design and software design, the precise ratio of the communication is most satisfied.According to the customer's requirement and other kinds of air-conditions, the paper chooses the heating, cooling and other working models for this air-condition, and also a series protecting steps to make high security of the air-condition. The fuzzy control strategy is an important key to the performance of the air-condition. The fuzzy-control of this system needs consider both the two indoor units and the outdoor unit. The working frequency of the compressor and the quality of the refrigerant are both depended on the temperature differences of two indoor units and the varying speed of temperature. Whether the fuzzy-control strategy works well influences the efficiency and the customer's comfort greatly. The paper modifies it according to the experiments to make the best working performance of the air-condition.
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