铁路空调客车变频调速制冷系统研究

Study on Refrigeration System of Speed Regulation by Frequency Conversion in Railway Air Conditioned Train

目前我国铁路空调客车的制冷量调节采用压缩机间歇运行的办法 ,此办法存在有较多问题。主要是这种阶梯式调节使车厢内温度场梯度波动大 ,车厢内温差达 4℃之多。其次耗能高。根据现场调查 ,在夏季空调工况下 ,沿用目前调节方式 ,车内温度每下调 1℃ ,每列车每年需多耗 5 5万度电。此外 ,还使空调列车的维修量增大。此种调节方式会使供电回路电压波动 ,缩短电器元件的使用寿命 ,增加维修量和更换元器件的数量。用压缩机变频调速方式来进行制冷量无级调节 ,可降低耗能 ,提高车内舒适度 ,进而达到提高运量的目标。压缩机变频调速系统在现车安装和静态试验的结果验证了这一方案的可行性。车厢内温差控制在 1℃范围内并连续可调 ;变频调速制冷系统用电量约为压缩机间歇运行调节的 1/ 2。

At present adjustment of refrigerated air amount for railway air conditioned train in china is realized by intersecutive pause of the compressor. The method has many problems. It is the adjustment that generates 4℃ difference due to great pulsation of the temperature field in coach. Its power consumption is high. According to investigation on site, in summer, when the present air conditioning system goes down by 1℃, the train consumes a power of 55 000 kWh more each year. What is more, the method causes more maintenance of the air conditioned train. It causes the voltage of the power supply circuit to pulsate, which results in reduced survice life of electric components, increased maintenance and more replacement of components. This paper points out that under the present condition, the conditioner employs frequency conversion to vary speed to perform non-grade adjustment of the refrigeration capacity with less power consumption. Thus it is more comfortable to ride the train. The static test of the speed regulation by frequency conversion proves that the system is feasible. The difference of temperature in the carriage is controlled within 1℃ and can be continuously adjusted. The power consumption of the conditioning system is about half of that of the former one.