无感无刷直流电动机技术在密度仪器上的应用

Application of Sensorless Brushless DC Motor Technology in Density Instrument

为了解决早期的密度仪器开关腿故障率高的问题,对该仪器进行了全面调查,发现单相交流电动机需要起动电容,大大增加了安全隐患。为此需要对电机控制系统进行重新设计,放弃对起动电容的使用。在简单阐述直流无刷电动机工作原理的基础上,重点介绍了无传感器控制技术,进而设计了电动机控制电路,应用到现有的密度仪器当中。结合设计的控制电路,详细介绍了密度仪器内无感无刷电动机的工作原理。在最后的测试中,三相输出波形完全正确,与设计目标相符。

In order to solve the problem of high failure rate of the early density instrument switch leg, the thorough investigation has been carried on. It was found that the single-phase AC motor need starting capacitance, which greatly increased the safety risk. The motor control system needed to be redesigned to give up the using of the starting capacitance. On the basis of working principle of the brushless DC motor and the sensorless control technology, the motor control circuit was designed and applied to the density instrument. Combined with the designed control circuit, the working principle of the sensorless brushless DC motor in the density instrument was introduced. The test results showed that the actual waveform was correct and consistent with the design goal.