Power supply system
A power supply system includes an assembled battery, a positive electrode-side power supply path, a negative electrode-side power supply path, and a capacitor unit. The capacitor unit includes a series connection of a plurality of capacitors having one end connected to the positive electrode power supply path and the other end connected to the negative electrode power supply path. An inter-capacitor connection point located between the capacitors forming the series connection is electrically connected to the inter-cell connection point.
1 . A power supply system to which an assembled battery configured by connecting a plurality of battery cells in series is applied, the power supply system comprising:
a positive electrode-side power supply path connected to a positive electrode-side power supply terminal of the assembled battery;
a negative electrode-side power supply path connected to a negative electrode-side power supply terminal of the assembled battery; and
a capacitor unit connected to the power supply paths,
wherein the capacitor unit comprises
a first capacitor having one end connected to the positive electrode-side power supply path and the other end connected to an inter-cell connection point between the battery cells in the assembled battery, or
a second capacitor having one end connected to the negative electrode-side power supply path and the other end connected to the inter-cell connection point, or
a series connection of a plurality of capacitors having one end connected to the positive electrode-side power supply path and the other end connected to the negative electrode-side power supply path, an inter-capacitor connection point between the capacitors forming the series connection being electrically connected to the inter-cell connection point, and
an electric path between the inter-cell connection point and the capacitor unit is insulated from a ground member.
2 . The power supply system according to claim 1 , wherein the inter-cell connection point is a midpoint along the plurality of battery cells connected in series in the assembled battery.
3 . The power supply system according to claim 1 , wherein a third capacitor is in an electric path connecting the capacitor unit and the inter-cell connection point.
4 . The power supply system according to claim 3 , comprising a plurality of the inter-cell connection points, and the capacitor unit is connected to each of the inter-cell connection points via the third capacitor.
5 . The power supply system according to claim 1 , further comprising a high voltage circuit including at least the assembled battery, the positive electrode-side power supply path, and the negative electrode-side power supply path, and a low voltage circuit whose input and output voltages are lower than input and output voltages of the high voltage circuit,
wherein the high voltage circuit is on a first conductive ground member with a first insulating member interposed therebetween, or is surrounded by the first conductive ground member with the first insulating member interposed therebetween,
the low voltage circuit is connected to a second conductive ground member, and
the first conductive ground member is insulated from the second conductive ground member by a second insulating member.
6 . The power supply system according to claim 5 , wherein the first conductive ground member is connected to an electric path between the inter-cell connection point and the capacitor unit.
7 . The power supply system according to claim 5 , wherein the first conductive ground member is insulated from the second conductive ground member by the second insulating member, and the power supply system further comprises a first diode unit that allows current to pass from the first conductive ground member to the second conductive ground member, and a second diode unit that allows current to flow from the second conductive ground member to the first conductive ground member.
8 . The power supply system according to claim 5 , wherein the first conductive ground member is insulated from the second conductive ground member by the second insulating member, and the power supply system further comprises a resistance unit connecting the first conductive ground member and the second conductive ground member, and
a resistance value of the resistance unit is lower than a maximum value of insulation resistance of the second insulating member.
9 . The power supply system according to claim 1 , wherein each of the power supply paths includes a relay switch for switching between power conduction and interruption of the power supply path.