Automatic Angle Control of Louver Blade Based on the Sensorless Estimation

This paper presents a improved sensorless open angle control scheme of the motorized louver system. In the proposed sensorless angle control method, the open angle of the louver blade can be controlled by the environmental temperature without any additional position sensor. In order to reduce the integrated angle error of the sensorless estimation, hysteresis open angle reference according to the temperature band is proposed. In the proposed control scheme, the open angle is not continuously determined. The 5-step open angle reference is determined by the 0.5 Celsius degree to reduce the low-speed operation region. Furthermore, the sensorless open angle controller, the non-linear reference voltage model is designed to consider the non-linear friction torque of the geared motor and louver blade. The proposed non-linear voltage reference model is designed to reduce the estimation error at the zero to low-speed region and overcome the non-linear friction torque. The integration of the voltage reference is reset to zero at the ±0.5 degree error region.<br/>In order to verify the proposed method, the proposed sensorless open angle control scheme of the motorized louver system is compared to the conventional sensorless control scheme. In the compared experimental results, the proposed method shows the reduced integrated snesorless angle error.