Chen, Dunzhi

Chen, Dunzhi

PROJECT TITLE: High Performance Sensorless V/F Control for Permanent Magnet Synchronous Machines

PhD period: 2018.04.01 – 2021.03.31. (has been prolonged till 2021.09.30)
Section: Electrical Machines
Research Programmes: E-Mobility and Industrial Drives 
Supervisor: Kaiyuan Lu
Co-supervisor: Dong Wang
Contact Information

Funding: Self-financing and Department of Energy Technology, AAU.


Sensorless drives for permanent magnet synchronous machines (PMSMs) are highly desired in various applications. There are mainly two sensorless schemes, namely sensorless field oriented control (FOC) and Volts per Hertz (V/f) control. In sensorless FOC methods, rotor position information is vital for a successful operation. To obtain this information, back-EMF and high frequency(HF) signal injection methods are used. However, these methods have limitations that Back-EMF methods only work well for medium to high speed range and HF signal injection methods for zero and low speed range. Also, for machines with little saliency, performances of signal injection methods are greatly sacrificed. Furthermore, to achieve full speed range sensorless control, these two methods need to be seamlessly combined, which further complicates controller design.

Compared with sensorless FOC, Volts per Hertz (V/f) control has a simpler control structure and does not require rotor position or speed estimation, so it is much easier to implement. The main drawback of existing V/f control methods is that they do not offer high dynamics while being able to achieve maximum torque per ampere operation in steady state. The goal of this project is to study new/improved V/f control methods with high dynamics. New ideas, such as active power control, based on analysis of existing V/f methods will be proposed and verified, leading to new V/f methods with high dynamics and secured stability.


Publications in journals and conference papers may be found at VBN.