Power supply system, vehicle incorporating the same and method for controlling power supply system

1. A power supply system for supplying driving electric power to a load device, comprising:

a power storage device electrically connected to said load device; and

a control device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device,

said load device including a voltage detecting unit for detecting a voltage applied to said load device, supply of electric power generated by a regenerative operation from said load device to said power storage device being stopped in response to a failure of said voltage detecting unit,

said control device detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said signal outputting unit including a current detecting unit for detecting an actual current that is input to or output from said power storage device, and

said control device calculating a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for said actual current, and a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for a command current to be input to or output from said power storage device set in accordance with requested electric power based on a user's operation, during a prescribed period of time, and determining presence or absence of activation of said interrupting device, based on the variation length of said actual current and the variation length of said command current.

2. The power supply system according to claim 1 , wherein

said control device uses a first threshold value and a second threshold value greater than said first threshold value, and determines that said interrupting device has activated when the variation length of said actual current is smaller than said first threshold value, and the variation length of said command current is greater than said second threshold value.

3. The power supply system according to claim 2 , wherein

a switching device is provided on a path connecting said power storage device and said load device, for switching between a conducting state and a non-conducting state between said power storage device and said load device, and

said control device switches said switching device into the non-conducting state where it determines that said interrupting device has activated.

4. The power supply system according to claim 2 , further comprising auxiliary equipment connected to said power storage device in parallel with said load device, wherein

said signal outputting unit comprises a device of said auxiliary equipment that is configured to output a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

said control device detects presence or absence of activation of said interrupting device based on said voltage decrease signal from said device.

5. The power supply system according to claim 4 , wherein

said device includes a voltage converting device configured to step down voltage of electric power from said power storage device.

6. The power supply system according to claim 4 , wherein

a switching device is provided on a path connecting said power storage device and said load device, for switching between a conducting state and a non-conducting state between said power storage device and said load device, and

said control device switches said switching device into the non-conducting state where it determines that said interrupting device has activated.

7. A vehicle comprising:

a power storage device;

a load device including a drive unit configured to generate driving force for said vehicle using electric power from said power storage device; and

a control device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device,

said load device including a voltage detecting unit for detecting a voltage applied to said load device, supply of electric power generated by a regenerative operation from said load device to said power storage device being stopped in response to a failure of said voltage detecting unit,

said control device detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said signal outputting unit including a current detecting unit for detecting an actual current that is input to or output from said power storage device, and

said control device calculating a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for said actual current detected by said current detecting unit, and a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for a command current to be input to or output from said power storage device set in accordance with requested electric power based on a user's operation, during a prescribed period of time, and determining whether said interrupting device has activated or not, based on the variation length of said actual current and the variation length of said command current.

8. The vehicle according to claim 7 ,

further comprising auxiliary equipment connected to said power storage device in parallel with said load device, wherein

said signal outputting unit comprises a device of said auxiliary equipment that is configured to step down voltage of electric power from said power storage device, and outputting a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

said control device detects presence or absence of activation of said interrupting device based on said voltage decrease signal from said voltage converting device.

9. A method for controlling a power supply system including a power storage device for supplying driving electric power to a load device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device, and

said load device including a voltage detecting unit for detecting a voltage applied to said load device,

said method comprising the steps of:

detecting a failure of said voltage detecting unit;

stopping supply of electric power generated by a regenerative operation from said load device to said power storage device in response to the failure of said voltage detecting unit; and

detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said signal outputting unit including a current detecting unit for detecting an actual current that is input to or output from said power storage device, and

the step of detecting presence or absence of activation of said interrupting device including the steps of:

calculating a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for said actual current detected by said current detecting unit, during a prescribed period of time;

calculating a variation length obtained by accumulating a magnitude of an amount of variation for each sampling period for a command current to be input to or output from said power storage device set in accordance with requested electric power based on a user's operation, during said prescribed period of time; and

determining presence or absence of activation of said interrupting device based on the variation length of said actual current and the variation length of said command current.

10. The method for controlling the power supply system according to claim 9 , wherein

said power supply system includes auxiliary equipment connected to said power storage device in parallel with said load device,

said signal outputting unit comprises a voltage converting device of said auxiliary equipment that is configured to step down voltage of electric power from said power storage device, and to output a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

said step of detecting presence or absence of activation of said interrupting device includes detecting presence or absence of activation of said interrupting device based on said voltage decrease signal from said voltage converting device.

11. A power supply system for supplying driving electric power to a load device, comprising:

a power storage device electrically connected to said load device; and

a control device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device,

said load device including a voltage detecting unit for detecting a voltage applied to said load device, supply of electric power generated by a regenerative operation from said load device to said power storage device being stopped in response to the failure of said voltage detecting unit,

said control device detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said power supply system further comprising auxiliary equipment connected to said power storage device in parallel with said load device,

said signal outputting unit comprises a device of said auxiliary equipment that is configured to output a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

said control device detecting presence or absence of activation of said interrupting device based on said voltage decrease signal from said device.

12. A vehicle comprising:

a power storage device;

a load device including a drive unit configured to generate driving force for said vehicle using electric power from said power storage device; and

a control device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device,

said load device including a voltage detecting unit for detecting a voltage applied to said load device, supply of electric power generated by a regenerative operation from said load device to said power storage device being stopped in response to a failure of said voltage detecting unit,

said control device detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said vehicle further comprising auxiliary equipment connected to said power storage device in parallel with said load device,

said signal outputting unit comprises a voltage converting device of said auxiliary equipment that is configured to step down voltage of electric power from said power storage device, and outputting a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

said control device detecting presence or absence of activation of said interrupting device based on said voltage decrease signal from said voltage converting device.

13. A method for controlling a power supply system including a power storage device for supplying driving electric power to a load device,

said power storage device including an interrupting device configured to activate where an internal pressure of said power storage device has exceeded a prescribed value to interrupt a conduction path of said power storage device, and

said load device including a voltage detecting unit for detecting a voltage applied to said load device,

said method comprising the steps of:

detecting a failure of said voltage detecting unit;

stopping supply of electric power generated by a regenerative operation from said load device to said power storage device in response to the failure of said voltage detecting unit; and

detecting presence or absence of activation of said interrupting device based on information from a signal outputting unit different from said voltage detecting unit,

said power supply system including auxiliary equipment connected to said power storage device in parallel with said load device,

said signal outputting unit comprises a voltage converting device of said auxiliary equipment that is configured to step down voltage of electric power from said power storage device, and outputting a voltage decrease signal indicating that an input voltage has decreased while driving is being requested, and

the step of detecting presence or absence of activation of said interrupting device including the step of detecting presence or absence of activation of said interrupting device based on said voltage decrease signal from said voltage converting device.