s02 sensorless control for electric motors

8/10/2019 S02 Sensorless Control for Electric Motors

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Sensorless Control for

Yang Hu

Tejas Bhandare

University of Central Florida, Orlando, FL 32816


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Outline

1)Advantages of Sensorless Control

3)Simulation Model of EKF Sensorless Control System


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Why Sensorless?

Motor control needs feedback information like rotor

position and speed, etc.

Mechanical sensors increases instability and cost of the

system

Simplicity

Lower cost


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Position Estimation

Back EMF

The rotating rotor will induce a voltage in the winding,

w c can e e ec e an use o es ma e e ro or

position

- . ,

voltage is too small that the signal to noise ratio is too

low. Signal injection

Inject some voltage or current signals (usually high

signals to detect rotor position


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Back EMF

he induced voltage

is dependent on therotor speed

By measuring current

and voltage of thes a or w n ngs, eback EMF information


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Model reference adaptive system

Two models one is forestimation, one is the realmodel

Every state variable in thers mo e s o serva e

Only current and voltages of

the real motor model is

Compare the two modelsand adjust the estimationmodel

Highly dependent onparameter accuracy


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State Observer or Kalman filter

Dynamic equation of state variables and output equation

x Ax Bu

Use some iteration to approach the real position/speedy Cx


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Signal Injection


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Implementation

Read some literature and implemented a PMSM

sensorless control system in Simulink

Extended Kalman filter is used for estimation. This is a

kind of observer method.

feedback to control the motor


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Kalman Filter


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System

State variables and PMSM dynamic equation

( )gx x

= L / R

Assume Ld = Lq = L .


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System

Observable variables are d-q currents. Use them as output

vector


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Kalman Filter

Estimate state variables of next time step, then calculate

the error covariance matrix, and also the error of

,

the coefficients

Traditional observer:


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Simulation System


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Extended Kalman Filter


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EKF Sensorless control

Successfully tracking the stroke without a sensor, and controlling well.


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References

Zedong Zheng; Fadel, M.; Yongdong Li; , "High Performance PMSM Sensorless Control with Load Torque Observation,"

EUROCON, 2007. The International Conference on "Computer as a Tool" , vol., no., pp.1851-1855, 9-12 Sept. 2007

Kye-Lyong Kang; Jang-Mok Kim; Keun-Bae Hwang; Kyung-Hoon Kim; , "Sensorless control of PMSM in high speed range

with iterative sliding mode observer," Applied Power Electronics Conference and Exposition, 2004. APEC '04. Nineteenth

Annual IEEE , vol.2, no., . 1111- 1116 vol.2, 2004

Sakamoto, K.; Iwaji, Y.; Endo, T.; Takakura, T.; , "Position and speed sensorless control for PMSM drive using direct position

error estimation," Industrial Electronics Society, 2001. IECON '01. The 27th Annual Conference of the IEEE , vol.3, no.,pp.1680-1685 vol.3, 2001

Hung-Chi Chen; Wei-Shun Huang; Jhen-Yu Liao; , "PMSM sensorless control with Coordinate Rotation Digital Computer,"

IECON 2010 - 36th Annual Conference on IEEE Industrial Electronics Society , vol., no., pp.951-955, 7-10 Nov. 2010

Yan Liang; Yongdong Li; , "Sensorless control of PM synchronous motors based on MRAS method and initial position

estimation," Electrical Machines and Systems, 2003. ICEMS 2003. Sixth International Conference on , vol.1, no., pp. 96- 99

vol.1, 9-11 Nov. 2003

Ji-Hoon Jang; Seung-Ki Sul; Jung-Ik Ha; Ide, K.; Sawamura, M.; , "Sensorless drive of surface-mounted permanent-magnet

motor by high-frequency signal injection based on magnetic saliency," Industry Applications, IEEE Transactions on , vol.39,. , . - , - .

Sepe, R.B.; Lang, J.H.; , "Real-time observer-based (adaptive) control of a permanent-magnet synchronous motor without

mechanical sensors," Industry Applications Society Annual Meeting, 1991., Conference Record of the 1991 IEEE , vol., no.,

pp.475-481 vol.1, 28 Sep-4 Oct 1991

Andreescu, G.-D.; Pitic, C.I.; Blaabjerg, F.; Boldea, I.; , "Combined Flux Observer With Signal Injection Enhancement for

Wide Speed Range Sensorless Direct Torque Control of IPMSM Drives," Energy Conversion, IEEE Transactions on , vol.23,

no.2, pp.393-402, June 2008 Ji-Hoon Jang; Jung-Ik Ha; Ohto, M.; Ide, K.; Seung-Ki Sul; , "Analysis of permanent-magnet machine for sensorless control

based on high-frequency signal injection," Industry Applications, IEEE Transactions on , vol.40, no.6, pp. 1595- 1604, Nov.-

Dec. 2004

s02 sensorless control for electric motors

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