Research on Vector Control and PWM Technique of Five-Phase PMSM - Intelligent Computing for Sustainable Energy and Environment - page 267

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Fig. 1. Windings structure of five-phase
PMSM

Fig. 2. Five-phase voltage source inverter

In this paper, the method of decoupling vector space is taken to establish
the mathematical model of five-phase PMSM, and the respective vector control
algorithm are discussed. Based on the structure of five-phase VSI, the SVPWM
modulation with near two vectors is applied. This method achieves that the
voltage of each subspace can be outputted at the same time, the low order
harmonics is eliminated, and the five-phase motor achieves the same control
features with the traditional three-phase PMSM.

2 Mathematic Model of Five-Phase PMSM

2.1 Model in Natural Coordinate

The voltage equation in natural coordinate of five-phase PMSM is

R s i s + d

Ψ s
dt

u s = (1)

u s =[ u A u B u C u D u E ] T , Where u s is is the voltage matrix,

R s is is the resistance matrix, R s = r s × I s ,

i s =[ i A i B i C i D i E ] T ,

i s is is the current matrix,

Ψ s =[ ψ A ψ B ψ C ψ D ψ E ] T .

Ψ s is is the flux matrix,

The flux equation is

Ψ s = L s i s + Ψ m

(2)

Where L s is is the inductance matrix.

Ψ m is the flux linkage of permanent magnet,
Ψ m =[ Ψ mA Ψ mB Ψ mC Ψ mD Ψ mE ] T
The flux linkage of permanent magnet

Ψ m is

⎡ ⎤ ⎡ ⎤

cosθ 0
cosθ 1
cosθ 2
cosθ 3
cosθ 4

cos 3 θ 0
cos 3 θ 1
cos 3 θ 2
cos 3 θ 3
cos 3 θ 4

⎣ ⎦ ⎣ ⎦

Ψ m = Ψ m 1 + Ψ m 3 (3)