变频压缩机性能仿真建模

为了提高变频压缩机性能仿真模型的精度和通用性,把变频压缩机的运行工况离散为无穷多个定速压缩机,在试验数据的基础上,提出了一套描述变频压缩机制冷剂质量流量和耗功率的模型形式,并给出了模型中参数的计算方法。用二次函数的形式描述基频下的制冷剂质量流量和压缩机耗功率,制冷剂相对质量流量与频率成幂函数的关系,压缩机相对耗功率的自然对数与频率满足二次函数形式。用3种不同的压缩机进行校核,制冷剂质量流量和压缩机耗功率的最大相对误差分别为3.95％和4.40％。

Modeling of variable speed compressors

The numerical analysis of the variable speed compressor is the core part of air conditioner models used for performance analyses and optimization. The accuracy and versatility of the model was improved by a the map-based model for fitting the performance curves of an inverter compressor. The actual operating performance of the inverter compressor was treated as the performance of an infinite number of constant speed compressors. At the base frequency, the refrigerant mass flow rate and the input compressor power were modeled second-order functions of the condensing and evaporating temperatures. The mass flow rate was a power function of compressor frequency and the power input was a second-order exponential function of the frequency. Experimental data for three compressors were used to validate the model, with the maximum error of the refrigerant mass flow rate of 3. 95% and of the input compressor power of 4. 40%, which are accurate enough for air conditioner simulations.