Petchmaneelumka Wandee, Riewruja Vanchai, Songsuwankit Kanoknuch, Rerkratn Apinai
School of Engineering, King Mongkut's Institute of Technology Ladkrabang, Ladkrabang, Bangkok 10520, Thailand.
Sensors (Basel). 2021 Sep 10;21(18):6069. doi: 10.3390/s21186069.
Variation in the ambient temperature deteriorates the accuracy of a resolver. In this paper, a temperature-compensation technique is introduced to improve resolver accuracy. The ambient temperature causes deviations in the resolver signal; therefore, the disturbed signal is investigated through the change in current in the primary winding of the resolver. For the proposed technique, the primary winding of the resolver is driven by a class-AB output stage of an operational amplifier (opamp), where the primary winding current forms part of the supply current of the opamp. The opamp supply-current sensing technique is used to extract the primary winding current. The error of the resolver signal due to temperature variations is directly evaluated from the supply current of the opamp. Therefore, the proposed technique does not require a temperature-sensitive device. Using the proposed technique, the error of the resolver signal when the ambient temperature increases to 70 °C can be minimized from 1.463% without temperature compensation to 0.017% with temperature compensation. The performance of the proposed technique is discussed in detail and is confirmed by experimental implementation using commercial devices. The results show that the proposed circuit can compensate for wide variations in ambient temperature.
环境温度的变化会降低旋转变压器的精度。本文介绍了一种温度补偿技术来提高旋转变压器的精度。环境温度会导致旋转变压器信号出现偏差；因此，通过旋转变压器初级绕组中电流的变化来研究受干扰的信号。对于所提出的技术，旋转变压器的初级绕组由运算放大器（运放）的AB类输出级驱动，其中初级绕组电流构成运放电源电流的一部分。采用运放电源电流传感技术来提取初级绕组电流。根据运放的电源电流直接评估由于温度变化引起的旋转变压器信号误差。因此，所提出的技术不需要对温度敏感的器件。使用所提出的技术，当环境温度升高到70°C时，旋转变压器信号的误差可以从无温度补偿时的1.463%最小化到有温度补偿时的0.017%。详细讨论了所提出技术的性能，并通过使用商用器件的实验实现得到了证实。结果表明，所提出的电路能够补偿环境温度的大幅变化。
