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Permanent Magnet Synchronous Machine (PMSM)

Symbol

Description

Permanent Magnet Synchronous Machine (PMSM)

Model of a three-phase Permanent Magnet Synchronous Machine (PMSM) with the sinusoidal back Electro-Motive Force (EMF). In motor operation torque and speed have the same sign. Rotor Angle is defined as the angle between the a-phase and the d-axis. In this model, the saturation can be modeled using a piecewise linear approximation of direct and quadratic axis inductances. Stator winding is star connected in this model. To access the neutral point pin, check the "Neutral Point" checkbox in the properties menu.

Electrical model and equations

vd_vq_circuits

v_a = R_s i_a + \frac{d}{dt} (L_{aa} i_a + L_{ab} i_b + L_{ac} i_c) + \frac{d }{dt} \phi_m \sin{(\omega_r t)}
v_b = R_s i_b + \frac{d}{dt} (L_{ba} i_a + L_{bb} i_b + L_{bc} i_c) + \frac{d }{dt}\phi_m \sin{(\omega_r t - \frac{2 \pi }{3})}
v_c = R_s i_c + \frac{d}{dt} (L_{ca} i_a + L_{cb} i_b + L_{cc} i_c) + \frac{d }{dt} \phi_m \sin{(\omega_r t + \frac{2 \pi }{3})}

where \phi_m = \frac{K_e}{ N_{ pp} } is the permanent magnet flux linkage, and \omega_r = N_{pp} \Omega is the electrical speed of the rotor field. Phase inductances (L_{aa}, L_{ab}, L_{ac},..., L_{cc}) are calculated from the rotor reference frame inductance (L_{d}, L_{q}) defined in the property panel as the incremental inductance.
This component will use the lineary interpolated inductance when the current is between the two segmented points.

Electromechanical equations

Electro-magnetic torque:

T_e = 1.5 * N_{ pp}*(i_q * \phi_d - i_d * \phi_q)

where \phi_d = L_d i_d + \phi_m and \phi_q = L_q i_q

Mechanical rotational speed \Omega:

J \frac{d\Omega}{ dt} = T_e - B \Omega

Library

Electrical > Motors

Parameters

Property Display Name Parameter Type Description
Rs Rs - Stator Resistance [Ohm] DoubleParameter Stator Winding Resistance [Ohm]
Ld Ld - Direct Axis Inductance [H] DoubleMatrixParameter Direct Axis Inductance [H]
Lq Lq - Quadratic Axis Inductance [H] DoubleMatrixParameter Quadratic Axis Inductance [H]
Ke Ke - Back-EMF Constant [V/(rad/sec)] DoubleParameter Back-EMF Constant
J J - Rotor Inertia [kg.m²] DoubleParameter Rotor Inertia [kg.m²]
B B - Rotor Friction Coefficient [N.m/(rad/s)] DoubleParameter Rotor Friction Coefficient [N.m/(rad/s)]
InitialSpeed Rotor Initial Speed [rad/s] DoubleParameter Rotor initial speed [ rad/s]
InitialCurrent Initial Current [A] DoubleArrayParameter Initial Current Vector [IA IB IC]
NPP NPP - Poles pairs IntParameter Number of pole pairs
ExposeNeutralPoint Neutral Point BoolParameter Expose Neutral Point (Boolean)

Pins

Property Pin Name Type Description
Pin_A A Electrical Phase A (Electrical)
Pin_B B Electrical Phase B (Electrical)
Pin_C C Electrical Phase C (Electrical)
Pin_R R RotationalMechanical Rotor (Rotational Mechanical)
Pin_Angle Angle ControlOut Rotor Angle in radians, electrical angle (Control)

Default Size

Width Height
8 8