| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a motor drive device and an electric vehicle that are capable of contributing to energy saving by avoiding waste of accumulated energy of a voltage variable type energy storage element. <P>SOLUTION: A motor drive device includes: an inverter INV that supplies AC power to a motor M<SB POS="POST">1</SB>; a secondary battery 1 that is connected between positive and negative DC bus bars of the inverter INV and serves as a first power supply; a voltage variable type energy storage element 2 that is connected between a neutral point of the motor M<SB POS="POST">1</SB>and the positive DC bus bar or the negative DC bus bar and serves as a second power supply; and a control circuit 100 that drives the inverter 3, energy transfer between the energy storage element 2 and the positive and negative DC bus bars being possible. The control circuit 100 includes: determination means 110 for determining a magnitude of a motor torque at the time of acceleration; and a motor control block 121 and a capacitor energy control block 131 that adjust a weak field range and a weak magnetic flux amount in a speed range of the motor M<SB POS="POST">1</SB>based on an output signal L<SB POS="POST">det</SB>of the determination means 110. <P>COPYRIGHT: (C)2012,JPO&INPIT |
