平成 30 年電気学会産業応用部門大会

Y-65

Experimental Verification of Vector Controlled
Magnetically Modulated Motor
Sawanth Krishna Machavolu*, Toshihiko Noguchi, and Masahiro Aoyama (Shizuoka University)

I. INTRODUCTION
This paper focuses on vector control of a magneticallymodulated motor (MMM). The structure of this motor isquite different from a standard PMSM because it has two
output shafts, i.e., an outer magnetic flux modulator and an
inner PM rotor. There have been several studies regarding
the optimum design of the motor, but the vector control using
an actual machine is still unexplored [1]. Therefore, thispaper discusses the control algorithm and examines its
performance with a prototype MMM.
II. PROTOTYPE AND EXPERIMENTAL SETUPThe MMM has relationship of the pole pair number ratios ofthe stator, the inner PM rotor, and the outer modulator, i.e.,
Ps: Ppm : Pmod = n : 2n : 3n (n is a natural number). The statorpole pair number is different from that of the inner rotor inthe MMM, which is the most important feature as comparedwith common PM motors. The prototype has been madewith n = 4.
The test prototype MMM is shown in Fig. 1. The motor isplaced in the middle between the two torque-meters placedon either end of the rotor shafts. Two load motors assuming
the drive shaft and the engine are mechanically connected
through the torque meters, respectively. Fig. 2 shows avector control block diagram for the prototype. Tworesolvers are used to detect the positions of the two rotors.
The current and phase angle are given as command values toperform the vector control. The DC bus voltage is 80 V andthe PWM frequency is 10 kHz. The angular displacementof the two rotors are related to the stationary reference frameas = t = Pmod mod t − Ppm pmt =  mod −  pm .
(1)

assist mode; 2) EV mode, and 3) regeneration mode. In
each driving mode, the following are checked: 1)
relationship between the torque and the gear ratio, and 2)
torque-current phase characteristics.
Fig. 3 shows the torque--axis current characteristics. Herethe current norm is fixed at a constant value of 90 A, and-axis current is kept at zero and -axis current is varied. Itis confirmed from the graph that the torque of the inner rotor
and the torque of the outer modulator are proportional to-axis current regardless of the driving modes, which
satisfies (3). Fig. 4 shows the torque-current phase characteristics. Here  is varied while the current norm isalso kept at constant value. Both of the rotors deliver theirtorque, keeping the gear ratio defined by (3) regardless of the change.
IV. CONCLUSION
This paper discussed the vector control of a magneticallymodulated motor, and various aspects of the motor have beenverified by simulating the three HEV driving modes.
REFERENCES[1] Y. Takeuchi, H. Kato, M. Tago, S. Ogasawara, and H. Sakai, “OperatingPrinciple and Control Method of the Magnetic Modulated Motor,” IEEJNational Convention Record, No.5-041, 2013, pp. 73-74.

Load 1Torque meter 1
Torque meter 2Fig. 1. Experimental setup.

The two-axis voltage equation used for the vector control isgiven by− Ev   R + pL − L  i  v  =  L R + pL i  +  3 LacF − E  ,(2)     8 N = Pmodmod − Ppm pm
4

Theory_τpm
Theory_τmod4

Measured_τpm
Measured_τmod322

Theory_τpm
Theory_τmod
Engine asist mode_τpmEngine asist mode_τmod
EV mode_τpm
EV mode_τmodRegeneration mode_τpm
Regeneration mode_τmod10

III. EXPERIMENTAL TEST RESULTS-1

Through the experimental tests, the following three driving
modes are examined, assuming a HEV operation: 1) engine-3-2［ Y - 65 ］

Load 2

Fig. 2. Block diagram of vector control.

Torque (Nm)where E and  are voltages due to asynchronouscomponents. On the other hand, the torque is given byPP s = s  pm = − s  mod .
(3)
Ppm
Pmod

Torque (Nm)

Keywords: Vector control, magnetically modulated motor,
experiment, HEV

0-2-4010203040 50 60 70
δ-axis current (A)80

Fig. 3. T-i characteristics.

90030 60 90 120 150 180 210 240 270 300 330 360
Current phase β(deg)Fig. 4. T- characteristics.

Ⓒ 2018 IEE Japan