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Wang, Hechao

PROJECT TITLE: Pulse-width Modulation Synthesized Sensorless Synchronous Machine Drives

PhD period: 2015.10.01 – 2018.09.30. (has been prolonged till 2019.09.30)

Section: Electrical Machines
Research Programme: E-Mobility and Industrial Drives
Supervisor: Kaiyuan Lu 
Co-Supervisor: Dong Wang
Contact Information

Funding: Department of Energy Technology, Aalborg University.


Synchronous machines have a huge interest for various industrial applications. For reducing the cost and increasing the reliability of the drive system, sensorless control techniques for synchronous machines have been intensively investigated and great performance improvements have been achieved. In the meantime, there is an increasing effort to simplify the control algorithm by e.g. avoiding the use of filters and improving the voltage injection scheme.

Pulse-Width Modulation (PWM) scheme contains high frequency voltage pulses, which may be used as injection voltage vectors for position estimation. This may require modification of the traditional PWM algorithm, integrating special voltage injection vectors that facilitate position estimation. Meanwhile the inverter voltage error which distorts the output voltage needs to be carefully treated. In addition, improved speed observer will also be investigated to improve the dynamic performance of sensorless drives.

The aim of this project is to develop robust, high performance sensorless synchronous machine drives. The main characteristics are to integrate sensorless control algorithm with PWM, avoiding additional injection voltage vectors and various filters required for position estimation in the existing methods. 


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