Power Inverter

{
  "publication_number": "US2012170217A1",
  "country": "US",
  "kind": "A1",
  "title": "Power Inverter",
  "abstract": "In a power inverter, a coolant passage is fixed to a chassis to cool the chassis; the chassis is divided into a first region and a second region by providing the coolant passage in the chassis; a power module is provided in the first region as fixed to the coolant passage; a capacitor module is provided in the second region; and the DC terminal of the capacitor module is directly connected to the DC terminal of the power module.",
  "claims": [
    "1. A power inverter comprising: a power module converting a direct current to an alternating current; a capacitor module smoothing the direct current; a coolant passage forming member providing a coolant passage; and a chassis holding the coolant passage forming member, wherein the coolant passage forming member is located between the power module and the capacitor module, and provides a through-hole adjacent to the coolant passage; the capacitor module comprises a capacitor cell, a positive busbar connecting to a first electrode of the capacitor cell, a negative busbar connecting to a second electrode of the capacitor cell, a capacitor positive terminal connecting the positive busbar to the power module through the through-hole, a capacitor negative terminal connecting the negative busbar to the power module through the through-hole, and a protecting member for protecting the capacitor positive terminal and the capacitor negative terminal; and the protecting member extends to the through-hole. 2. A power inverter according to claim 1, wherein: the power module has a positive terminal that extends to an area facing the through-hole and a negative terminal that extends to an area facing the through-hole; a tip of the capacitor positive terminal is directly connected to the positive terminal; a tip of the capacitor negative terminal is directly connected to the negative terminal. 3. A power inverter according to claim 2, wherein: the positive terminal, the negative terminal, the capacitor positive terminal and the capacitor negative terminal are provided respectively in a plural; the plurality of positive terminal are connected to the plurality of capacitor positive terminal; and the plurality of negative terminal are connected to the plurality of capacitor negative terminal. 4. A power inverter according to claim 2, wherein: the coolant passage forming member provides an opening connected to the coolant passage; the power module comprises a metal plate providing a fin, wherein the metal plate covers the opening with the fin extending to the coolant passage. 5. A power inverter according to claim 1, wherein: the capacitor module comprises a case accommodating the capacitor cell, wherein the protecting member and the case is formed integrally. 6. A power inverter comprising: a power module converting a direct current to an alternating current; a capacitor module smoothing the direct current; a coolant passage forming member providing a coolant passage; and a chassis holding the coolant passage forming member, wherein the coolant passage forming member is located between the power module and the capacitor module, and provides a through-hole adjacent to the coolant passage; the capacitor module comprises a capacitor cell, a positive busbar connecting to a first electrode of the capacitor cell, a negative busbar connecting to a second electrode of the capacitor cell, a capacitor positive terminal connecting the positive busbar to the power module through the through-hole, and a capacitor negative terminal connecting the negative busbar to the power module through the through-hole, wherein the capacitor positive terminal and the capacitor negative terminal are surrounded by a shield; and the shield extends to the through-hole. 7. A power inverter according to claim 6, wherein: the power module has a positive terminal that extends to an area facing the through-hole and a negative terminal that extends to an area facing the through-hole; a tip of the capacitor positive terminal is directly connected to the positive terminal; a tip of the capacitor negative terminal is directly connected to the negative terminal. 8. A power inverter according to claim 7, wherein: the positive terminal, the negative terminal, the capacitor positive terminal and the capacitor negative terminal are provided respectively in a plural; the plurality of positive terminal are connected to the plurality of capacitor positive terminal; and the plurality of negative terminal are connected to the plurality of capacitor negative terminal. 9. A power inverter according to claim 7, wherein: the coolant passage forming member provides an opening connected to the coolant passage; the power module comprises a metal plate providing a fin, wherein the metal plate covers the opening with the fin extending to the coolant passage. 10. A power inverter according to claim 6, wherein: the capacitor module comprises a case accommodating the capacitor cell, wherein the shield and the case is formed integrally. 11. A power inverter comprising: a power module converting a direct current to an alternating current; a capacitor module smoothing the direct current; a coolant passage forming member providing a coolant passage; and a chassis holding the coolant passage forming member, wherein the coolant passage forming member is located between the power module and the capacitor module, and provides a through-hole adjacent to the coolant passage; the capacitor module comprises a capacitor cell, a positive busbar connecting to a first electrode of the capacitor cell, a negative busbar connecting to a second electrode of the capacitor cell, a capacitor positive terminal connecting the positive busbar to the power module through the through-hole, a capacitor negative terminal connecting the negative busbar to the power module through the through-hole, and a terminal cover covering the capacitor positive terminal and the capacitor negative terminal; and the terminal cover extends to the through-hole. 12. A power inverter according to claim 11, wherein: the power module has a positive terminal that extends to an area facing the through-hole and a negative terminal that extends to an area facing the through-hole; a tip of the capacitor positive terminal is directly connected to the positive terminal; a tip of the capacitor negative terminal is directly connected to the negative terminal. 13. A power inverter according to claim 12, wherein: the positive terminal, the negative terminal, the capacitor positive terminal and the capacitor negative terminal are provided respectively in a plural; the plurality of positive terminal are connected to the plurality of capacitor positive terminal; and the plurality of negative terminal are connected to the plurality of capacitor negative terminal. 14. A power inverter according to claim 12, wherein: the coolant passage forming member provides an opening connected to the coolant passage; the power module comprises a metal plate providing a fin, wherein the metal plate covers the opening with the fin extending to the coolant passage. 15. A power inverter according to claim 11, wherein: the capacitor module comprises a case accommodating the capacitor cell, wherein the terminal cover and the case is formed integrally."
  ],
  "description_excerpt": "1. Field of the Invention\n\nThe present invention relates to a power inverter that converts Direct Current (DC) power into Alternate Current (AC) power and vice versa.\n\n2. Description of Related Art\n\nThe power inverter includes a function with which DC power supplied from a DC power supply is converted into AC power to be supplied to an AC electricity load such as an electric rotating machine, and a function with which AC power generated by an electric rotating machine is converted into DC power to be supplied to a DC power supply. To perform the conversion function, the power inverter further includes an inverter circuit which includes a switching device, and by repeating conduction operation and interrupt operation with the switching device, the power inverter converts from DC power to AC power or AC power to DC power.\n\nSpike voltage is generated by inductance that exists in the circuit because the switching operation cuts off the current. For reducing the spike voltage, it is preferable to provide a smoothing capacitor and to reduce inductance at a DC circuit. A technology for controlling spike voltage by reducing inductance is disclosed in Japanese Laid Open Patent Publication No. 2002-34268 (patent document 1). According to the patent document 1, inductance is reduced by shortening wiring between the smoothing capacitor and the switching device so as to reduce the spike voltage.\n\nAn in-car power inverter is provided with DC power from an in-car battery and converts the DC power into three-phase AC power to be supplied to an electric rotating machine for vehicle, etc.",
  "cpc": [
    "H02M 7/5387",
    "H02M 7/003",
    "H02M 7/219",
    "H05K 7/20927",
    "H10W 90/753"
  ],
  "ipc": [
    "H05K 7/20",
    "H02M 1/00"
  ],
  "assignees": [
    "Hitachi Ltd"
  ],
  "inventors": [
    "Fusanori NISHIKIMI",
    "Kinya Nakatsu"
  ],
  "filing_date": "2012-03-14",
  "publication_date": "2012-07-05",
  "priority_date": "2007-08-09",
  "application_number": "US-201213419884-A",
  "family_id": "54207935",
  "cited_by_count": 95,
  "citations": [
    "US20070002594A1",
    "US20070109715A1",
    "US20070165376A1"
  ]
}