Abstract: In a method for predicting deterioration of grease, the grease is applied between a semiconductor module and a cooler. The semiconductor module accommodates a semiconductor element. The method for predicting deterioration includes predicting deterioration of the grease after specified heat cycles by using: a variable G1/G2 that is acquired by dividing an initial storage modulus G1 of the grease by an initial loss modulus G2 of the grease at an expected maximum use temperature of the semiconductor element; and distortion dD of the grease at the time when the initial storage modulus G1 and the initial loss modulus G2 have the same value.

Abstract: A cooler may include: a housing including a coolant space in which coolant flows; partition walls partitioning the coolant space into a plurality of flow channels; and a plurality of cooling fins located in each of the flow channels. The partition walls may be curved tortuously such that each of the flow channels comprises wide portions and narrow portions. The wide portions and the narrow portions may be arranged alternately in each of the flow channels in a direction along which the coolant flows. A number of the cooling fins located in each of the wide portions may be greater than a number of the cooling fins located in each of the narrow portions.

Abstract: A semiconductor device may include a stack in which a cooler and a semiconductor module are stacked, the semiconductor module housing a semiconductor element; a contact plate contacting the stack in a stacking direction of the semiconductor module and the cooler; and a spring contacting the contact plate and pressurizing the stack via the contact plate in the stacking direction, wherein the spring may contact a center portion of the contact plate in a direction perpendicular to the stacking direction, and a recess or a cavity may be provided at the center portion of the contact plate, the recess facing the stack.

Abstract: A cooler may include: a housing including a coolant space in which coolant flows; partition walls partitioning the coolant space into a plurality of flow channels; and a plurality of cooling fins located in each of the flow channels. The partition walls may be curved tortuously such that each of the flow channels comprises wide portions and narrow portions. The wide portions and the narrow portions may be arranged alternately in each of the flow channels in a direction along which the coolant flows. A number of the cooling fins located in each of the wide portions may be greater than a number of the cooling fins located in each of the narrow portions.

Abstract: In a method for predicting deterioration of grease, the grease is applied between a semiconductor module and a cooler. The semiconductor module accommodates a semiconductor element. The method for predicting deterioration includes predicting deterioration of the grease after specified heat cycles by using: a variable G1/G2 that is acquired by dividing an initial storage modulus G1 of the grease by an initial loss modulus G2 of the grease at an expected maximum use temperature of the semiconductor element; and distortion dD of the grease at the time when the initial storage modulus G1 and the initial loss modulus G2 have the same value.

Abstract: A semiconductor device may include a stack in which a cooler and a semiconductor module are stacked, the semiconductor module housing a semiconductor element; a contact plate contacting the stack in a stacking direction of the semiconductor module and the cooler; and a spring contacting the contact plate and pressurizing the stack via the contact plate in the stacking direction, wherein the spring may contact a center portion of the contact plate in a direction perpendicular to the stacking direction, and a recess or a cavity may be provided at the center portion of the contact plate, the recess facing the stack.

Abstract: In a converter circuit of an electric power conversion device, an adjustment portion divides a voltage of a battery input to a semiconductor module, by a first capacity element and a second capacity element that are connected in series to each other. Then, a middle point between the first capacity element and the second capacity element is connected to a cooler to fix a potential thereof. The electric power conversion device can ensure that a waveform of a surge voltage that is generated on a creepage surface between a lead frame terminal and the cooler has a negative voltage range (a range where an offset voltage is applied).

Abstract: A power converter includes a plurality of power cards, a plurality of coolers and a pressure member. Each of the power cards houses a semiconductor element. The plurality of coolers is laminated with the power cards. The cooler includes a body, a gasket and a metal plate. The body is made of resin, and has an opening that is provided in a side surface of the cooler that faces the adjacent power card. A surface on one side of the metal plate is configured to close the opening through the gasket, and the other surface faces the power card. The pressure member is configured to apply a pressure in a laminating direction on a lamination unit. The opening is sealed by the metal plate by pressure applied by the pressure member on the lamination unit.

Abstract: In a converter circuit of an electric power conversion device, an adjustment portion divides a voltage of a battery input to a semiconductor module, by a first capacity element and a second capacity element that are connected in series to each other. Then, a middle point between the first capacity element and the second capacity element is connected to a cooler to fix a potential thereof. The electric power conversion device can ensure that a waveform of a surge voltage that is generated on a creepage surface between a lead frame terminal and the cooler has a negative voltage range (a range where an offset voltage is applied).

Abstract: A semiconductor device includes a semiconductor module. The semiconductor module includes a package made of resin. The package contains a semiconductor element and a heat sink. The heat sink has a thermal conductive surface exposed on a part of one surface of the package. The semiconductor device includes an insulating plate, which is a part of a cooler, facing the thermal conductive surface of the heat sink and a resin surface around the thermal conductive surface, and pressed against the semiconductor module. At least a part of the thermal conductive surface comprises a recessed region recessed with respect to the resin surface. A solid heat transfer layer is interposed between the recessed region of the thermal conductive surface and the insulating plate, and is not interposed between the resin surface and the insulating plate.

Abstract: A semiconductor device includes a semiconductor module. The semiconductor module includes a package made of resin. The package contains a semiconductor element and a heat sink. The heat sink has a thermal conductive surface exposed on a part of one surface of the package. The semiconductor device includes an insulating plate, which is a part of a cooler, facing the thermal conductive surface of the heat sink and a resin surface around the thermal conductive surface, and pressed against the semiconductor module. At least a part of the thermal conductive surface comprises a recessed region recessed with respect to the resin surface. A solid heat transfer layer is interposed between the recessed region of the thermal conductive surface and the insulating plate, and is not interposed between the resin surface and the insulating plate.

Abstract: A power converter includes a plurality of power cards, a plurality of coolers and a pressure member. Each of the power cards houses a semiconductor element. The plurality of coolers is laminated with the power cards. The cooler includes a body, a gasket and a metal plate. The body is made of resin, and has an opening that is provided in a side surface of the cooler that faces the adjacent power card. A surface on one side of the metal plate is configured to close the opening through the gasket, and the other surface faces the power card. The pressure member is configured to apply a pressure in a laminating direction on a lamination unit. The opening is sealed by the metal plate by pressure applied by the pressure member on the lamination unit.

Abstract: A cooling fin structure used in a cooler for an electric device includes a plurality of pin fins (71) arranged in a zigzag form in a coolant passage (80). Each of the pin fins (71) has a circular portion (72) having a circular cross-section, and irregularly shaped portions (73) provided contiguously on the upstream and downstream sides of the circular portion (72) as viewed in a direction of flow of the coolant. The irregularly shaped portions (73) have an outer peripheral surface (75) that is formed along a circumference (130) having a center at a center point (101) of the circular portion (72) of a pin fin (71, 71B) that is located adjacent to the pin fin (71, 71A) having the irregularly shaped portions (73), in an oblique direction relative to the direction of flow of the coolant.

Abstract: A cooler is provided which includes a heat discharging unit in which a plurality of heat discharge fins are placed in a line and a coolant flows in a passage between the heat discharge fins, an inflow-side coolant reservoir provided extending in a lined direction of the heat discharge fins and connected to a side of one end of the passage between the heat discharge fins through a first diaphragm portion, and an outflow-side coolant reservoir provided extending in the lined direction of the heat discharge fins and connected to a side of the other end of the passage between the heat discharge fins through a second diaphragm portion. An inflow-side fin is formed on a surface of the inflow-side coolant reservoir opposing the first diaphragm portion, and a circulation cross-sectional area of the inflow-side coolant reservoir is set smaller than a circulation cross-sectional area of the outflow-side coolant reservoir.

Abstract: A semiconductor element cooling structure includes a semiconductor element, a heat sink on which the semiconductor element is mounted, and a heat storage member attached to the semiconductor element in a manner to be located opposite to the heat sink with respect to the semiconductor element and having a case and a latent heat storage material.

Abstract: A cooler includes a base plate, fins, a coolant discharge passageway, and a coolant supply passageway. The coolant supply passageway includes a supply passageway partition that divides the coolant supply passageway into a plurality of divided supply passageways. The supply passageway partition extends in a coolant flowing direction within the coolant supply passageway. A first coolant supply port supplies the coolant to a first divided supply passageway that is at least one of the divided supply passageways, from one side along the base plate. A second coolant supply port supplies the coolant to a second divided supply passageway that is at least one of the divided supply passageways, from another side along the base plate. Coolant nozzles jet the coolant toward the fins. The coolant nozzles include a coolant nozzle communicating with the first divided supply passageway and a coolant nozzle communicating with the second divided supply passageway.

Abstract: A cooler is disposed in contact with an electronic component to cool the electronic component. The cooler includes a flow passage for a cooling medium, a heat transfer portion, and a non-conductive portion. The flow passage is provided in the cooler. The heat transfer portion is in contact with the electronic component and contacts the cooling medium that flows through the flow passage. The non-conductive portion is provided in the heat transfer portion.

Abstract: A Peltier element is provided so that an electrically conductive plate forming a heat absorbing portion is in close proximity to an insulating layer and an electrically conductive plate forming a heat radiating portion is provided in close proximity to an insulating layer. The Peltier element has one end connected to a branch line branched from a power line, and has the other end electrically connected to an electrode plate. Further, the Peltier element receives from the branch line a portion of electric power supplied to a power transistor, and outputs it to the electrode plate. In other words, the Peltier element uses the portion of the electric power supplied to the power transistor, to absorb heat generated by the power transistor and radiate it toward a heat radiating plate.

Abstract: A cooling fin structure used in a cooler for an electric device includes a plurality of pin fins (71) arranged in a zigzag form in a coolant passage (80). Each of the pin fins (71) has a circular portion (72) having a circular cross-section, and irregularly shaped portions (73) provided contiguously on the upstream and downstream sides of the circular portion (72) as viewed in a direction of flow of the coolant. The irregularly shaped portions (73) have an outer peripheral surface (75) that is formed along a circumference (130) having a center at a center point (101) of the circular portion (72) of a pin fin (71, 71B) that is located adjacent to the pin fin (71, 71A) having the irregularly shaped portions (73), in an oblique direction relative to the direction of flow of the coolant.

Abstract: A cooler is provided which comprises a heat discharging unit in which a plurality of heat discharge fins are placed in a line and a coolant flows in a passage between the heat discharge fins, an inflow-side coolant reservoir provided extending in a lined direction of the heat discharge fins and connected to a side of one end of the passage between the heat discharge fins through a first diaphragm portion, and an outflow-side coolant reservoir provided extending in the lined direction of the heat discharge fins and connected to a side of the other end of the passage between the heat discharge fins through a second diaphragm portion. An inflow-side fin is formed on a surface of the inflow-side coolant reservoir opposing the first diaphragm portion, and a circulation cross-sectional area of the inflow-side coolant reservoir is set smaller than a circulation cross-sectional area of the outflow-side coolant reservoir.