Southern Taiwan University of Science and Technology Permanent Magnet Synchronous Motors Intructor: Prof. Chi-Jo Wang Reporter: Nguyen Phan Thanh ID Student: DA220202

Permanent Magnet Synchronous Motors Contents Introduction Mathematical model of PMSM Sensor Control Architechture High performance motor control application

Permanent Magnet Synchronous Motors Introduction PM synchronous motors are widely used in industrial servo-applications due to its high-performance characteristics. Compact High efficiency (no excitation current) Smooth torque Low acoustic noise Fast dynamic response (both torque and speed) A synchronous motor differs from an asynchronous motor in the relationship between the mechanical speed and the electrical speed. In a synchronous motor, the supplied voltages have the same frequency as the mechanical motor speed. In an asynchronous motor, the end mechanical speed is different from the input frequency, and the relationship between input frequency and mechanical speed varies depending on mechanical load applied to the motor.

Permanent Magnet Synchronous Motors Introduction

Permanent Magnet Synchronous Motors Introduction 2-axis reference frame:The stator and rotor equations are referred to a common frame of reference Stator (stationary) reference frame : non-rotating Synchronous reference frame: d, q axis rotates with the synchronous angular velocity

Permanent Magnet Synchronous Motors Introduction The stator reference axis for the a-phase direction: maximum mmf when a positive a-phase current is supplied at its maximum level. The rotor reference frame: -D-axis: permanent magnet flux -Q-axis: 90 degree ahead of d-axis The d-q model has been used to analyze reluctance synchronous machines.

Permanent Magnet Synchronous Motors Introduction As the motor spins, there is an angle between rotor magnetic field and stator magnetic field If these two magnetic fields are not ninety degrees from each other, there will be an offset angle between Back EMF and Current: =>the torque production at a given input power will not be the maximum

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Introduction With this animation we can see how the commutation angle is always ninety degrees ahead of the rotor. On the left we see how the motor spins with Field Oriented Control. On the voltage diagrams we show how the output voltages have a sinusoidal shape. On the lower right we see the rotor angle changing from minus pi (minus one eighty degrees) to plus pi (plus one eighty degrees).

Permanent Magnet Synchronous Motors Mathematical model of PMSM The mathematical model of PMSM is constructed based on the rotating d-q frame fixed to the rotor, described by the following equations: Where: v­d, vq are the d and q axis voltages id, iq are the d and q axis currents Rs is the phase winding resistance Ld, Lq are the d and q axis inductance is the rotating speed of magnet flux is the permanent magnet flux linkage.

Permanent Magnet Synchronous Motors Mathematical model of PMSM

Permanent Magnet Synchronous Motors Operation of PMSM Command Pulse Deviation Counter Kp Kv Ki M E Speed detection Current Feedback Speed Feedback Pulse Feedback _ + Position Gain Speed Gain Current Gain Motor Encoder Closed_loop Control

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder PI, Fuzzy, Neural network are used to the speed loop of PMSM drive Vector control is used to the current loop of PMSM drive to let it reach the linearity and decouple characteristics.

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The entire process is illustrated in this block diagram, including coordinate transformations, PI iteration, transforming back and generating PWM

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The Id reference controls rotor magnetizing flux The Iq reference controls the torque output of the motor Id and Iq are only time-invariant under steady-state load conditions

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The outputs of the PI controllers provide Vd and Vq, which is a voltage vector that is sent to the motor. A new coordinate transformation angle is calculated based on the motor speed, rotor electrical time constant, Id and Iq.

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The Vd and Vq output values from the PI controllers are rotated back to the stationary reference frame, using the new angle. This calculation provides quadrature voltage values vα and vβ.

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The vα and vβ values are transformed back to 3-phase values va, vb, vc. The 3-phase voltage values are used to calculate new PWM duty-cycle values that generate the desired voltage vector.

Permanent Magnet Synchronous Motors Sensor Control Architechture DC Speed loop Current loop Power Current controller modifyClark-1 Speed Controller Park-1 + + PI PWM1 d,q PWM2 — — SVPWM PWM3 PWM4 Inverter a,b,c PWM5 + PI PWM6 — d,q A/D convert a,b,c Park Clark QEP sin /cos of Flux angle A B PMSM Z 1-Z-1 Encoder The transformation angle, theta, and motor speed are coming from an optical encoder mounted on the shaft of the motor.

Permanent Magnet Synchronous Motors Motor Driver Controller

Permanent Magnet Synchronous Motors High performance motor control application Industrial drives, e.g., pumps, fans, blowers, mills, hoists, handling systems Elevators and escalators, people movers, light railways and streetcars (trams), electric road vehicles, aircraft flight control surface actuation

Permanent Magnet Synchronous Motors Thank you for listening!