Abstract: A power semiconductor device includes a power module unit and a heat sink. An uneven portion is formed in a module base in the power module unit. The uneven portion includes a depression portion and a buffer depression portion. An uneven portion is formed in a heat sink base unit in the heat sink. The uneven portion and the uneven portion are fitted together by crimping so that the module base of the power module unit and a heat dissipation spreader of the heat sink are integrated. The buffer depression portion is left as a space.

Abstract: A controller of a hybrid system including an internal combustion engine and a motor generator connected to each other via a belt includes processing circuitry configured to execute a power generation process that applies a load to the engine by controlling the motor generator to generate power when a first execution condition of an idling stop is satisfied, a slip rate calculation process that calculates a slip rate of the belt based on a rotational speed of the engine and a rotational speed of the motor generator while the power generation process is being executed, a determination process that determines whether or not a second execution condition of the idling stop is satisfied after waiting until a predetermined period elapses, when the slip rate is equal to or more than a threshold, and an idling stop process, when determining that the second execution condition is satisfied.

Abstract: An electronic controller for a diesel engine (1) performs primary injection control in which primary injection of fuel is controlled based on an operational status of the diesel engine and additional injection control in which additional injection of the fuel is controlled for estimation of a cetane number of the fuel. The electronic controller includes a control means that, as the additional injection control, causes a plurality of fuel injections to be performed at different injection timings as the additional injection, calculates the amount of increase in torque of a crankshaft (14) due to each of the fuel injections, estimates injection timing at which misfiring starts to occur based on a trend of variation in the calculated torque increase amount as the injection timing of the fuel injections is shifted in one direction, and estimates the cetane number of the fuel based on the estimated injection timing.

Abstract: In one embodiment, a total fuel injection amount is calculated from a torque required by an engine. A division ratio of a pre-injection amount that achieves both suppression of ignition delay of fuel from a main injection and suppression of a peak value of a heat production ratio of combustion from the main injection is calculated. Upper and lower limit guards are given to the obtained divided amount, and the divided injection amount is calculated. The injection amount of the main injection is obtained by subtracting the divided injection amount from the total fuel injection amount.

Abstract: In one embodiment, a determination is made of whether or not in a condition in which a compressed gas temperature will reach a fuel self-ignition temperature by only a compression operation in the compression stroke, and in a case where the compressed gas temperature will reach the fuel self-ignition temperature, pilot injection is judged to be unnecessary, so this pilot injection is prohibited.

Abstract: A cetane number estimation method is provided in which: the preliminary injection is preformed multiple times at different compression end temperatures with a fuel tank (26) containing fuel having a predetermined cetane number, and an engine torque increase caused by each preliminary injection is calculated and the relation between the compression end temperatures at the respective preliminary injections and the engine torque increases caused by the respective preliminary injections is determined; the compression end temperature and the engine torque increase at a predetermined reference point on the relation are recorded as a basic compression eng temperature and a basic engine toque increase; the preliminary injection is performed at the basic compression end temperature and an engine torque increase caused by this preliminary injection is calculated; and the cetane number of fuel is estimated based on the relation between the calculated engine torque increase and the basic engine torque increase.

Abstract: In one embodiment, a total pilot injection amount is calculated from the difference between a compressed gas temperature in a cylinder and a fuel self-ignition temperature. As pilot injection, a plurality of instances of divided pilot injection are performed, and by setting the injection amount per one instance of divided pilot injection to an injector minimum limit injection amount, each divided pilot injection amount is suppressed, and the penetration of fuel is suppressed to a low level so that attachment of fuel to a wall face is avoided, and also, fuel is caused to accumulate in the center portion of the cylinder.

Abstract: A cetane number estimation method is provided in which: the preliminary injection is preformed multiple times at different compression end temperatures with a fuel tank (26) containing fuel having a predetermined cetane number, and an engine torque increase caused by each preliminary injection is calculated and the relation between the compression end temperatures at the respective preliminary injections and the engine torque increases caused by the respective preliminary injections is determined; the compression end temperature and the engine torque increase at a predetermined reference point on the relation are recorded as a basic compression eng temperature and a basic engine toque increase; the preliminary injection is performed at the basic compression end temperature and an engine torque increase caused by this preliminary injection is calculated; and the cetane number of fuel is estimated based on the relation between the calculated engine torque increase and the basic engine torque increase.

Abstract: In one embodiment, a total fuel injection amount is calculated from a torque required by an engine. A division ratio of a pre-injection amount that achieves both suppression of ignition delay of fuel from a main injection and suppression of a peak value of a heat production ratio of combustion from the main injection is calculated. Upper and lower limit guards are given to the obtained divided amount, and the divided injection amount is calculated. The injection amount of the main injection is obtained by subtracting the divided injection amount from the total fuel injection amount.

Abstract: In one embodiment, a determination is made of whether or not in a condition in which a compressed gas temperature will reach a fuel self-ignition temperature by only a compression operation in the compression stroke, and in a case where the compressed gas temperature will reach the fuel self-ignition temperature, pilot injection is judged to be unnecessary, so this pilot injection is prohibited.

Abstract: An electronic controller for a diesel engine (1) performs primary injection control in which primary injection of fuel is controlled based on an operational status of the diesel engine and additional injection control in which additional injection of the fuel is controlled for estimation of a cetane number of the fuel. The electronic controller includes a control means that, as the additional injection control, causes a plurality of fuel injections to be performed at different injection timings as the additional injection, calculates the amount of increase in torque of a crankshaft (14) due to each of the fuel injections, estimates injection timing at which misfiring starts to occur based on a trend of variation in the calculated torque increase amount as the injection timing of the fuel injections is shifted in one direction, and estimates the cetane number of the fuel based on the estimated injection timing.

Abstract: An electronic control unit 30 of a diesel engine 10 stores a relationship between a required fuel injection amount and a corresponding injection command signal. The unit 30 generates the injection command signal corresponding to the required fuel injection amount based on the stored relationship, and drives injectors 20 based on the injection command signal to inject fuel. The unit 30 includes a shifting section, which forcibly changes the engine rotational speed by temporarily shifting the fuel injection mode between a first injection mode and a second injection mode. The first injection mode is a mode in which an after injection is executed after a main injection. The after injection has less fuel injection amount than the main injection. The second injection mode is a mode in which the after injection is not executed.

Abstract: An electronic control unit 30 of a diesel engine 10 stores a relationship between a required fuel injection amount and a corresponding injection command signal. The unit 30 generates the injection command signal corresponding to the required fuel injection amount based on the stored relationship, and drives injectors 20 based on the injection command signal to inject fuel. The unit 30 includes a shifting section, which forcibly changes the engine rotational speed by temporarily shifting the fuel injection mode between a first injection mode and a second injection mode. The first injection mode is a mode in which an after injection is executed after a main injection. The after injection has less fuel injection amount than the main injection. The second injection mode is a mode in which the after injection is not executed.