Sensorless PMSM Drive with DC-link Current Measurement

The paper proposes a motion-sensorless control method for permanent magnet synchronous motor drives when only the DC-link current is measured instead of the motor phase currents. A two-phase pulse-width modulation method is used, allowing the DC-link current to be sampled twice in a switching period at uniform intervals during active voltage vectors. A method is proposed for obtaining the current feedback for vector control, and an adaptive observer is used for estimating the rotor speed and position. The estimation is augmented with a high- frequency signal injection method at low speeds; a modified high- frequency excitation voltage is proposed for better performance. The proposed method enables stable operation of the permanent magnet synchronous motor drive in a wide speed range and under various loads. The effectiveness of the proposed method is demonstrated both by simulations and laboratory experiments.

[1]  J. Kolar,et al.  Influence of the modulation method on the conduction and switching losses of a PWM converter system , 1990, Conference Record of the 1990 IEEE Industry Applications Society Annual Meeting.

[2]  A. Nabae,et al.  A novel PWM scheme of voltage source inverters based on space vector theory , 1990 .

[3]  T.G. Habetler,et al.  Control strategies for direct torque control using discrete pulse modulation , 1989, Conference Record of the IEEE Industry Applications Society Annual Meeting,.

[4]  M. Schroedl,et al.  Sensorless control of an external rotor PMSM in the whole speed range including standstill using DC-link measurements only , 2004, 2004 IEEE 35th Annual Power Electronics Specialists Conference (IEEE Cat. No.04CH37551).

[5]  Slobodan N. Vukosavic,et al.  Sensorless induction motor drive with a single DC-link current sensor and instantaneous active and reactive power feedback , 2001, IEEE Trans. Ind. Electron..

[6]  S. Bolognani,et al.  Single sensor current control of AC servodrives using digital signal processors , 2002 .

[7]  A. Piippo,et al.  Analysis of an adaptive observer for sensorless control of PMSM drives , 2005, 31st Annual Conference of IEEE Industrial Electronics Society, 2005. IECON 2005..

[8]  F. Blaabjerg,et al.  Single current sensor technique in the DC-link of three-phase PWM-VS inverters. A review and the ultimate solution , 1996, IAS '96. Conference Record of the 1996 IEEE Industry Applications Conference Thirty-First IAS Annual Meeting.

[9]  T.M. Jahns,et al.  Phase Current Reconstruction for AC Motor Drives using a DC-link Single Current Sensor and Measurement Voltage Vectors , 2006, 2005 IEEE 36th Power Electronics Specialists Conference.

[10]  A. Piippo,et al.  Adaptive observer combined with HF signal injection for sensorless control of PMSM drives , 2005, IEEE International Conference on Electric Machines and Drives, 2005..

[11]  Barry W. Williams,et al.  Derivation of motor line-current waveforms from the DC-link current of an inverter , 1989 .