采用车厢底部出风的变频热泵空调在低温地区大巴车辆上的应用研究

纯电动大巴空调冬季制热是目前行业普遍关注的焦点问题,受大巴空调厂家技术影响,大部分电动空调热泵制热在环境温度0℃左右将无法启动,所以目前行业冬季制暖主要采用燃油炉或PTC加热方式。燃油炉与PTC加热能耗高,严重影响整车续航里程。热泵大巴空调可实现-15℃正常热泵制热,补气增焓技术可实现-25℃正常热泵制热。另外,在冬季制热时,暖风从上部的风道往下吹,大部分热风下不去,造成了车厢上部温度高,脚部温度过低,非常影响舒适性。通过从上部风口引一些风道到脚部的方式,提高车厢底部的热风循环,提高车厢热泵制热的舒适性,从而验证了大巴车厢底部出风对热泵空调制热效果的影响。综合上述,对热泵空调在低温地区冬季热泵制热效果及节能效果进行对比测试,通过对比热泵空调和电加热器的温升速率、耗电量和舒适性等参数,可得知热泵空调升温速度快、温控精度高、耗电量少,变频热泵空调更舒适、更节能。

Study on the Application of Variable Frequency Heat Pump Air Conditioning Using the Bottom of the Carriage On Bus in Low Temperature Area

Winter heating of pure electric bus air conditioning is the focus of the current industry.Affected by the technology of bus air conditioning manufacturers,most electric air conditioning heat pumps cannot be started at the ambient temperature of 0℃or so.Therefore,the industry mainly USES oil furnace or PTC heating in winter.Fuel furnace and PTC heating energy consumption is high,seriously affecting the vehicle mileage.The heat pump bus air conditioning can realize the normal heat pump heating at-15℃,and the normal heat pump heating at-25℃can be realized by the gas replenishment and enthalpy increase technology.In addition,in winter heating,the warm wind blows down from the upper air duct,and most of the hot wind cannot go down,resulting in high temperature on the upper part of the carriage and low temperature on the feet,which greatly affects comfort.The hot air circulation at the bottom of the bus is improved by means of some air ducts from the upper air tuyere to the footstep,and the comfort of the heat pump is improved,so as to verify the influence of the air outlet at the bottom of the bus on the heating effect of the heat pump air-conditioning.Based on the above comparison test of heat pump air conditioning in the northeast region in winter heat pump heating effect and energy saving effect.In addition,by comparing the temperature rise rate,power consumption and comfort parameters of the heat pump air conditioning and electric heater,it can be known that the heat pump air conditioning heating speed is fast,the temperature control precision is high,the power consumption is low,and the inverter heat pump air conditioning is more comfortable and energy-saving.