房间空调器低环境温度制冷控制策略分析及试验验证

Low ambient temperature refrigeration control strategy of room air conditioners and experimental verification

通过对房间空调器室外机风机控制策略、蒸发器冻结保护策略、电子膨胀阀制冷剂流量调节策略、压缩机运行频率控制策略等进行优化,提升低环境温度下冷凝压力和蒸发压力,从而提升低环境温度下的制冷量。研究结果表明,通过控制策略的调整及应用,环境温度为-15℃时空调器制冷量为环境温度为35℃时制冷量的69.8%,较改进前机型提升13.2%;环境温度在-6℃以下时,室外机风机会进入启停控制,室外机风机启停最小时间间隔80s,室外机风机停止期间系统最高压力为3.88MPa,在安全可靠的时间与压力范围内。

Through optimizing the fan control strategy of room air conditioner outdoor unit,evaporator freezing protection strategy,electronic expansion valve refrigerant flow adjustment strategy,compressor operating frequency control strategy,etc.,the condensing pressure and evaporation pressure at low ambient temperature increase,thereby further improving cooling capacity at low ambient temperature.The research results show that through the adjustment and application of the control strategy,the cooling capacity of the air conditioner at-15℃ambient temperature is 69.8%of the cooling capacity at 35℃ambient temperature,which is 13.2%higher than that of the model before the improvement;at ambient temperature below-6℃,the outdoor unit's fan will enter the start-stop control.The minimum time interval between the outdoor unit's fan start and stop is 80 s.The maximum system pressure during the outdoor unit fan stop is 3.88 MPa,which is within a safe and reliable range of time and pressure.