Some thoughts on extracting perspectives from ealfa and Ebeta

1、 The angle extracted from the back EMF can be directly atan2 To calculate the , It can also be done through PLL obtain

2、 I use simulation PLL Extract frequency and angle , There are two debugging experiences recorded

 1）PLL The input error is ：Ealfa*cosθ - Ebeta*sinθ; instead of -Ealfa*cosθ - Ebeta*sinθ;

2）PLL Of Kp and KI Gain adjustment ,KI Basically unchanged , With Ealfa The increase in frequency , If smaller Kp Words , The estimated phase lag is large , It's time to add Kp Gain can reduce the phase error .