A control device for controlling a balance correction device which equalizes voltages of a first electric storage cell and a second electric storage cell connected in series, wherein
- the balance correction device comprises:
- an inductor having one end electrically connected to a connection point between one end of the first electric storage cell and one end of the second electric storage cell;
- a first switching element electrically connected between another end of the inductor and another end of the first electric storage cell;
- and
- at least one of (i) a second switching element and (ii) a rectifier, electrically connected between the other end of the inductor and the other end of the second electric storage cell, wherein
- the rectifier passes current flowing in a direction from a negative pole side of the second electric storage cell toward a positive pole side of the second electric storage cell and does not pass current flowing in a direction from the positive pole side of the second electric storage cell toward the negative pole side of the second electric storage cell, and
- the control device comprises:
- a current information acquiring unit which acquires information about a current value of current flowing in the inductor;
- and
- a control signal supplying unit which supplies the balance correction device with a control signal for controlling the balance correction device, such that a valley in an absolute value of the current value satisfies a predetermined condition, based on information about the current value acquired by the current information acquiring unit, during at least part of a period of time in which the balance correction device operates;
- wherein the control signal supplying unit supplies the control signal such that (i) a value of the valley is equal to a predetermined first value, (ii) a value of the valley is greater than the first value, or (iii) a value of the valley is within a predetermined range including the first value;
- (a) if the balance correction device comprises at least the second switching element, the control signal supplying unit supplies the first switching element and the second switching element with the control signal for controlling the first switching element and the second switching element to be turned on and off such that, while the balance correction device operates, the balance correction device repeatedly performs a switching operation including (i) a first operation in which the first switching element is turned on and the second switching element is turned off and (ii) a second operation in which the first switching element is turned off and the second switching element is turned on;
- (b) if the balance correction device comprises the second switching element and the rectifier arranged in parallel, the control signal supplying unit supplies the first switching element and the second switching element with the control signal for controlling the first switching element and the second switching element to be turned on and off such that, while the balance correction device operates, the balance correction device repeatedly performs a switching operation including (i) a first operation in which the first switching element is turned on and the second switching element is turned off, and at least one of (ii) a second operation in which the first switching element is turned off and the second switching element is turned on and (iii) a third operation in which the first switching element is turned off and the second switching element is turned off;
- or
- (c) if the balance correction device comprises at least the rectifier, the control signal supplying unit supplies the first switching element with the control signal for controlling the first switching element to be turned on and off such that, while the balance correction device operates, the balance correction device repeatedly performs a switching operation including (i) a first operation in which the first switching element is turned on and (ii) a second operation in which the first switching element is turned off.