“Performance Representation of Variable-speed Compressor for Inverter Air Conditioners Based on Experimental Data

Department of Building Science, Tsinghua University, Beijing, 100084, China
International Journal of Refrigeration (Impact Factor: 2.24). 12/2004; 27(8):805-815. DOI: 10.1016/j.ijrefrig.2004.02.008


Variable speed control of compressors is one of the best methods to regulate the capacity of heat pumps and air conditioners. An analysis is conducted for modeling the variable speed compressor for simulation of inverter air conditioner and heat pump. Having scattered the real operation performance of inverter compressor into infinite operation performance of constant speed compressor, the map-based method is utilized to fit the performance curves of inverter compressor. The model is built at the basic frequency and the map condition as the second-order function of condensation temperature and evaporation temperature. Then it is corrected by the compressor frequency as the second-order function of frequency and by the actual operating condition as the actual specific volume of the suction gas. This method is used to set up simulation models of three different compressors. Compared with the data provided by the compressor manufacturers, the average relative errors are less than 2, 3 and 4% for refrigerant mass flow rate, compressor power input and coefficient of performance (COP), respectively. This model of variable speed compressor is suitable for the simulation of inverter air conditioner and heat pump systems. Based on the experimental data and simulation model, the frequency at zero mass flow rate and power input at zero frequency are discussed and the relation between COP and compressor frequency is analyzed.

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    • "In their test, the compressor operated across a wide range, from 1100 to 9000 rpm. Shao et al. (2004) determined the performance of a variable speed compressor for inverter air conditioners. Based on their experimental data and simulation model, the frequency at zero mass flow rate and the power input at zero frequency are discussed, and the relation between COP and compressor frequency was analyzed. "
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    • "Therefore , two independent containers with a large volume are connected to Port E and Port C of the valve in the simplified physical model (shown in Fig. 4). The compressor model is established according to the results from Shao [15] on the basis of the compressor real performance data provided by the manufacturer. It is assumed that the compressor takes 5 s to reach the rated frequency. "
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