Dynamo-electric machine control system and vehicle driving system including the same

• US 8,373,367 B2
• Filed: 07/01/2009
• Issued: 02/12/2013
• Est. Priority Date: 07/31/2008
• Status: Active Grant

• Current Assignee: Aisin AW Company Limited (Aisin Corp.)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.)
• Inventors: Yoshida, Takashi, Saha, Subrata, Ogino, Daisuke, Izawa, Jin, Aoki, Kazuo
• Primary Examiner(s): Ip, Paul
• Application Number:
  US12/458,146
• Publication Number:
  US 20100026222A1
• Time in Patent Office: 1,322 Days
• Field of Search: 318/400.23, 318/139, 318/430, 318/432, 318/434, 318/800, 180/65.3
• US Class Current: 318/139
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/10 for automatic control superimposed on human control to limit the acceleration of the vehicle, e.g. to prevent excessive motor current electric devices for safety purposes B60L3/00
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: H02P 29/02 Providing protection against overload without automatic interruption of supply protection against faults of stepper motors H02P8/36
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

Abstract

A dynamo-electric machine control system including a dynamo-electric machine and an inverter that is interposed between a battery and the dynamo-electric machine and that controls a current flowing through the dynamo-electric machine, wherein a rotation speed and an output torque of the dynamo-electric machine are controlled by the inverter, the dynamo-electric machine control system includes a battery power deriving unit that derives a battery power to be supplied from the battery when the dynamo-electric machine is operated at the rotation speed and the output torque; a limit power determining unit that variably determines a limit power, which is a maximum allowable value of the battery power, in accordance with a battery voltage; and a torque limiting unit that limits the torque of the dynamo-electric machine such that the battery power derived by the battery power deriving unit does not exceed the limit power.

Claims

1. A dynamo-electric machine control system including a dynamo-electric machine and an inverter that is interposed between a battery and the dynamo-electric machine and that controls a current flowing through the dynamo-electric machine, wherein a rotation speed and an output torque of the dynamo-electric machine are controlled by the inverter, the dynamo-electric machine control system comprising:

a battery power deriving unit that derives a battery power to be supplied from the battery when the dynamo-electric machine is operated at the rotation speed and the output torque;

a limit power determining unit that variably determines a limit power, which is a maximum allowable value of the battery power, in accordance with a battery voltage; and

a torque limiting unit that limits the torque of the dynamo-electric machine such that the battery power derived by the battery power deriving unit does not exceed the limit power,

wherein the limit power determining unit determines the smaller of a first limit power, which is set at a fixed value regardless of the battery voltage, and a second limit power, which is set on the basis of a multiplication value of the battery voltage and a predetermined overcurrent threshold such that a battery current remains smaller than the predetermined overcurrent threshold even when the battery voltage varies, as the limit power.

2. The dynamo-electric machine control system according to claim 1, wherein the first limit power and the second limit power are set by subtracting in advance a value corresponding to a control delay power, which is an increase in the battery power caused by a control delay relative to the dynamo-electric machine.

3. The dynamo-electric machine control system according to claim 1, further comprising a battery power variation rate deriving unit that derives a variation rate of the battery power,

wherein, during rapid variation in which the battery power variation rate derived by the battery power variation rate deriving unit is larger than a predetermined battery power rapid variation threshold, a rapid variation second limit power, which is set at a smaller value than the second limit power, is set instead of the second limit power.

4. The dynamo-electric machine control system according to claim 3, wherein, during the rapid variation, a rapid variation first limit power, which is set at a smaller value than the first limit power, is set instead of the first limit power.

5. The dynamo-electric machine control system according to claim 1, further comprising a rotation speed variation rate deriving unit that derives a variation rate in the rotation speed of the dynamo-electric machine,

wherein, during rapid variation in which the rotation speed variation rate derived by the rotation speed variation rate deriving unit is larger than a predetermined rotation speed rapid variation threshold, a rapid variation second limit power, which is set at a smaller value than the second limit power, is set instead of the second limit power.

6. The dynamo-electric machine control system according to claim 5, wherein, during the rapid variation, a rapid variation first limit power, which is set at a smaller value than the first limit power, is set instead of the first limit power.

7. A vehicle driving system comprising:

the dynamo-electric machine control system according to claim 1;

a first dynamo-electric machine and a second dynamo-electric machine serving as the dynamo-electric machine; and

a power transfer mechanism for distributing a driving force by a drive source other than the first dynamo-electric machine and the second dynamo-electric machine,

wherein one of the driving force distributed by the power transfer mechanism is transmitted to a vehicle wheel, another one of the driving force distributed by the power transfer mechanism is transmitted to the first dynamo-electric machine, and a driving force generated by the second dynamo-electric machine is transmitted to the vehicle wheel.

8. The vehicle driving system according to claim 7, wherein

the power transfer mechanism includes a planetary gear mechanism having, in order of rotation speed, a first rotary element, a second rotary element, and a third rotary element, and

the first dynamo-electric machine is connected to the first rotary element, the drive source other than the dynamo-electric machine is connected to the second rotary element, and the second dynamo-electric machine and the third rotary element are connected to the vehicle wheel.