EXTRACTION OF HIGH RESOLUTION POSITION INFORMATION FROM SINUSOIDAL ENCODERS

摘要

Precision motion control in industrial automation systems is placing increasing demands on the position feedback mechanisms used in the constituent servo drives of these systems. Traditional position transducer solutions based on resolvers or incremental encoders are increasingly being replaced by sinusoidal encoders that offer much higher position and speed resolution. The hardware or software techniques used to interface to the sinusoidal encoders can have a measurable impact on the achieved position resolution and accuracy. This paper compares the achievable performance levels with different interface techniques. All techniques are implemented on a common hardware platform. Each method is fully described and comparisons and tradeoffs are made in terms of computational burden, achievable position bandwidth, the resolution of both the speed and position achievable as well as the sensitivity of each method to common transducer offset, gain, and phase errors.