Power source system, power supply control method for the power source system, power supply control program for the power source system, and computer-readable recording medium with the power supply control program recorded thereon
The present invention provides a power source system that increases the power supply capacity of a power source device and continuously supplies the power necessary for a load device when a power source device stops. A control unit has a state quantity setting unit that sets a first target state quantity indicating a state of charge of the power storage device that is to be a target value when charge and discharge of the power storage device are controlled. When the power source device stops, the state quantity setting unit can change the first target state quantity to a second target state quantity that is to be a target value exceeding the first target state quantity and can increase the target state quantity of the power storage device. As a result, when the power source device stops, charge and discharge of the power storage device are controlled on the basis of the target state quantity exceeding that during the operation of the power source device. Therefore, the state of charge of the power storage device can be improved over that during the operation of the power source device. As a result, the power supply capacity of the power source device can be increased and the power necessary for the load device can be continuously supplied, in place of the power source device.
1. A power source system comprising:
a power source device that supplies power to a load device;
a power storage device that supplies, in place of the power source device, power to the load device when the power source device stops; and
a control unit that controls power supply from the power storage device to the load device,
wherein the control unit has:
a stop determination unit that determines whether the power supply device has stopped; and
a state quantity setting unit that sets a first target state quantity indicating a state of charge of the power storage device that is to be a target value when charge and discharge of the power storage device are controlled, in order to maintain the state of charge of the power storage device within a predetermined range, and
the state quantity setting unit changes the first target state quantity to a second target state quantity that is to be a target value exceeding the first target state quantity in a case where the stop determination unit determines that the power source device has stopped.
2. The power source system according to claim 1 , wherein
the control unit further has:
a state quantity calculation unit that uses data of at least one type from among voltage data, current data, and temperature data of the power storage device to calculate a present state quantity that indicates a present state of charge of the power storage device; and
a state quantity determination unit that determines whether the present state quantity of the power storage device is lower than the second target state quantity, and
the state quantity setting unit changes the first target state quantity to the second target state quantity in a case where the power source device is determined to have stopped and in a case where the present state quantity of the power storage device is determined to be lower than the second target state quantity.
3. The power source system according to claim 2 , wherein
the control unit further has an input power calculation unit that calculates an inputable power that can be inputted in the power storage device in order to charge the power storage device, by using the present state quantity of the power storage device that is calculated by the state quantity calculation unit, and sets a power that is higher than the calculated inputable power of the power storage device as a power that is to be actually inputted in the power storage device in a case where the stop determination unit determines that the power source device has stopped.
4. The power source system according to claim 2 , wherein
the control unit further has an output power calculation unit that calculates an outputable power that can be outputted by the power storage device by using the present state quantity of the power storage device that is calculated by the state quantity calculation unit, and sets a power that is lower than the calculated outputable power of the power storage device as a power that is to be actually outputted from the power storage device when the stop determination unit determines that the power source device has stopped.
5. The power source system according to claim 4 , wherein
the load device has a plurality of power consumption modes that include at least a normal power consumption mode and a low power consumption mode, and the power consumption mode of the load device is shifted to the low power consumption mode in a case where a power that is lower than the outputable power of the power storage device that is calculated by the power calculation unit is set as a power that is to be actually outputted from the power storage device.
6. A power supply control method for a power source system provided with a power storage device that supplies, in place of a power source device, power to a load device when the power source device that supplies power to the load device stops, the power supply control method comprising:
a first step of setting a first target state quantity indicating a state of charge of the power storage device that is to be a target value when charge and discharge of the power storage device are controlled, in order to maintain the state of charge of the power storage device within a predetermined range; and
a second step of controlling charge and discharge of the power storage device on the basis of the first target state quantity of the power storage device that is set in the first step,
wherein the first step includes a step of changing the first target state quantity to a second target state quantity that is to be a target value exceeding the first target state quantity when the power source device stops.
7. A computer-readable recording medium that has recorded thereon a power supply control program for a power source system provided with a power storage device that supplies, in place of a power source device, power to a load device when the power source device that supplies power to the load device stops,
wherein the power supply control program causes a computer to function as:
a stop determination unit that determines whether the power supply device has stopped; and
a state quantity setting unit that sets a first target state quantity indicating a state of charge of the power storage device that is to be a target value when charge and discharge of the power storage device are controlled, in order to maintain the state of charge of the power storage device within a predetermined range,
the state quantity setting unit changing the first target state quantity to a second target state quantity that is to be a target value exceeding the first target state quantity when the stop determination unit determines that the power source device has stopped.