高温高压试验装置热风循环与变频控制设计与实践

Design and Practice of Hot Air Circulation and Frequency Conversion Control in High Temperature and High Pressure Test Equipment

设计并实施一种具有内外循环功能的热风循环与变频控制装置,通过在热风加热区设置导流筒,分割电阻加热器和高压釜之间的环形区域热气流,产生具有内外风道的热风循环系统。通过电动阀门切换实现内循环加热、外循环降温两种功能,根据不同试验阶段温度跟踪保护控制要求,采用频率分段控制方法进行风量风压实时调节,以最快速度按照试验要求对釜内试验介质温度进行精确控制,保证釜体试验安全,完成高温高压试验。该方法能够有效提高电热风利用率和换热效率,降低噪音,消除振动,满足高温高压试验技术要求,系统操作简单,节电效果明显。

A hot air circulation and frequency conversion control device with the function of internal and external circulation are designed.The hot air circulation system with internal and external air ducts is generated by setting a guide cylinder in the hot air heating area,dividing the hot air flow in the annular area between the resistance heater and the autoclave.Two functions of internal circulation heating and external circulation cooling are realized by switching the electric valve.According to the requirements of temperature tracking protection control in different test stages,the frequency subsection control method is used for real-time adjustment of air volume and air pressure,and the temperature of the test medium in the kettle is accurately controlled according to the test requirements at the fastest speed to ensure the safety of the kettle test and complete the high temperature and high pressure test.This method can effectively improve the utilization rate and heat exchange efficiency of electric hot air,reduce noise,eliminate vibration,and meet the technical requirements of high temperature and high pressure test.The system is simple in operation and has obvious power saving effect.