Patent ID: 11888419
Assignee: JIANGSU UNIVERSITY
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  Y | IPC H

Claim 0:
1. A unified open-circuit fault-tolerant control method for a vector control (VC) drive system and a direct torque control (DTC) drive system of a five-phase permanent magnet fault-tolerant motor, comprising the following steps:
step 1) establishing a mathematical model of various currents of the five-phase permanent magnet fault-tolerant motor under normal operation:
wherein currents iA, iB, iC, iD, and iE of the five-phase permanent magnet fault-tolerant motor under normal operation are as follows:, [
   
    
     
      
       i
       A
      
     
    
    
     
      
       i
       B
      
     
    
    
     
      
       i
       C
      
     
    
    
     
      
       i
       D
      
     
    
    
     
      
       i
       E
      
     
    
   
   ]
  
  =
  
   
    [
    
     
      
       
        sin
        ⁢
          
        θ
       
      
      
       
        cos
        ⁢
          
        θ
       
      
      
       
        sin
        ⁢
          
        3
        ⁢
        θ
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        θ
       
      
     
     
      
       
        sin
        ⁢
          
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        sin
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
     
     
      
       
        sin
        ⁢
          
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        sin
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
     
     
      
       
        sin
        ⁢
          
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        sin
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
     
     
      
       
        sin
        ⁢
          
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
      
       
        sin
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
     
    
    ]
   
   [
   
    
     
      
       i
       
        d
        ⁢
        1
       
       *
      
     
    
    
     
      
       i
       
        q
        ⁢
        1
       
       *
      
     
    
    
     
      
       i
       
        d
        ⁢
        3
       
       *
      
     
    
    
     
      
       i
       
        q
        ⁢
        3
       
       *
      
     
    
   
   ]
  
 

wherein, γ=72°; θ is an electrical angle of a rotor position; id1* and iq1* are direct-axis and quadrature-axis components of a predetermined value of a fundamental current; and id3* and iq3* are direct-axis and quadrature-axis components of a predetermined value of a third harmonic current;
step 2) obtaining fault-tolerant currents under an open circuit of a single phase, open circuits of two non-adjacent phases and open circuits of two adjacent phases, and analyzing a fault-tolerant mechanism;
step 3) constructing a torque controller based on a difference between a predetermined speed and a detected speed to obtain a predetermined torque Te* to suppress a torque ripple of the motor after a fault, wherein a load disturbance, system parameter changes, and an electromagnetic torque ripple caused by the fault are considered;
step 4) detecting the five-phase currents iA, iB, iC, iD, and iE of the five-phase permanent magnet fault-tolerant motor, and obtaining current components id1, iq1, id3, and iq3 in a two-phase rotating coordinate system through Clark and Park transforms;
wherein, the current components of the five-phase permanent magnet fault-tolerant motor in the two-phase rotating coordinate system are expressed as follows:, [
   
    
     
      
       i
       
        d
        ⁢
        1
       
      
     
    
    
     
      
       i
       
        q
        ⁢
        1
       
      
     
    
    
     
      
       i
       
        d
        ⁢
        3
       
      
     
    
    
     
      
       i
       
        q
        ⁢
        3
       
      
     
    
   
   ]
  
  =
  
   
    [
    
     
      
       
        cos
        ⁢
          
        θ
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
     
     
      
       
        
         -
          
         sin
        
        ⁢
          
        θ
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
     
     
      
       
        cos
        ⁢
          
        3
        ⁢
        θ
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        cos
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
     
     
      
       
        
         -
          
         sin
        
        ⁢
          
        3
        ⁢
        θ
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          γ
         
         )
        
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           2
           ⁢
           γ
          
         
         )
        
       
      
      
       
        
         -
         s
        
        ⁢
        in
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           3
           ⁢
           γ
          
         
         )
        
       
      
      
       
        
         -
          
         sin
        
        ⁢
          
        3
        ⁢
        
         (
         
          θ
          -
          
           4
           ⁢
           γ
          
         
         )
        
       
      
     
    
    ]
   
   [
   
    
     
      
       i
       A
      
     
    
    
     
      
       i
       B
      
     
    
    
     
      
       i
       C
      
     
    
    
     
      
       i
       D
      
     
    
    
     
      
       i
       E
      
     
    
   
   ]
  
 

step 5) calculating direct-axis and quadrature-axis fundamental voltages of the VC drive system and the DTC drive system based on the current components id1 and iq1 in the two-phase rotating coordinate system and the predetermined torque Te*;
step 6) obtaining direct-axis and quadrature-axis third harmonic voltages through the current components id3 and iq3 in the two-phase rotating coordinate system, based on a control strategy of zero third harmonic current;
step 7) calculating winding phase voltages in a fault mode based on the fault-tolerant mechanism and the direct-axis and quadrature-axis voltages;
step 8) obtaining predetermined phase voltages in a fault-tolerant operation mode based on a back-electromotive force (EMF) and the winding phase voltages in the fault mode; and
step 9) processing the predetermined phase voltages by a voltage source inverter, and achieving undisturbed operation of the VC drive system and the DTC drive system of the five-phase permanent magnet fault-tolerant motor under open-circuit fault through chaotic pulse width modulation (CPWM).