中文摘要：

在恒温型热线风速测量系统中,当放大器增益、热线工作过热比、惠斯通桥臂电阻和偏置电压等参量配置不当时,恒温型控制回路会进入失效状态使系统不能正常工作。本文分别对上述参量引起热线风速测量系统失效的机理进行了仿真研究,结果表明：惠斯通桥臂电阻确定了系统固有稳定工作区的大小,当热线工作过热比和放大器增益配置点进入固有稳定工作区时,系统在任何工况下均能稳定工作,否则在其他参量配置不当时就会失效;提高偏置电压能使系统脱离失效状态恢复正常工作。因此,提出了基于偏置电压的恒温型热线风速测量系统稳定性控制方法。试验结果表明,基于偏置电压的稳定性控制方法能有效避免系统失效,且调节过程简单,便于提高恒温型热线风速测量系统的测量性能。

英文摘要：

In hotwire wind velocity measurement system with constant temperature control loop （CTCL）, when the amplifier gain, hotwire operation overheat ratio, Wheatstone bridge arm resistances, offset voltage and etc. are not in an appropriate configuration, the CTCL will oscillate, which makes the hotwire measurement system not be able to work properly. In this paper, the failure mechanism of the hotwire wind velocity measurement system under CTCL caused by the above parameters was studied and simulated. The simulation results show that the Wheastone bridge arm resistances determine the inherent stable operation region size ; the system will never fail un- der any working condition when the configuration point of the hotwire operation overheat ratio and amplifier gain is in the inherent stable operation region; otherwise the system will fail when the other parameters are configured improperly; and increasing the offset voltage can make the system get out of the failure state and restore to normal operation. Therefore, the stability control method for the hotwire wind velocity measurement system with CTCL based on the offset voltage was proposed. The test results show that the offset voltage based sta- bility control method can effectively avoid the system failure, and the adjustment process is simple; and the proposed method can improve the measurement performance of the hotwire wind velocity measurement system with CTCL easily.