Ultraprecision circulating cooling water machine using bidirectional control of cooling and heating power

A circulating cooling water machine using agile bidirectional cooling and heating power control method is developed to produce circulating cooling water of high temperature stability and good dynamic performance. Cooling module based on thermoelectric cooling and multilayer compact structure is proposed to achieve cooling power output resolution at sub-watt level and quick response. Heating module based on a compact solenoid-in-tube structure is proposed to achieve heating power output with sub-watt level resolution and quick response. Experiments indicate that temperature stability of ± 3 mK, regulating resolution of 5 mK and regulating time of 128 s corresponding to 1 K step of circulating cooling water temperature are achieved with the developed machine. Thus, the developed machine can satisfy the challenging requirements of precision manufacturing.