RU2754594C1 - Controller for hybrid system - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to a controller for a hybrid system and, in particular, to a controller for controlling a hybrid system made with the ability to generate driving torque using an internal combustion engine and a motor generator. The device contains a unit for detecting operating conditions for the controller, a unit for calculating the total required torque, a unit for dividing the total required torque, a unit for estimating the total moment of losses of the internal combustion engine, a unit for calculating the compensatory torque of the motor, a unit for performing torque compensation.

EFFECT: providing compensation for the lost torque caused by the internal combustion engine and decreasing the reduction in torque.

8 cl, 12 dwg

Description

Technology area

The present invention relates to a controller for a hybrid system, and in particular to a controller for controlling a hybrid system configured to generate driving torque using an internal combustion engine and a motor generator.

State of the art

In recent years, internal combustion engines have been developed having a supercharger (which includes all force induction devices including, for example, turbochargers). Some superchargers use energy from the exhaust gas to boost the combustion engine in order to generate more drive torque. Such internal combustion engines can be installed, for example, in vehicles, construction machinery or the like. Also be disclosed are internal combustion engines with two superchargers, such as a first supercharger and a second supercharger, or more (multiple) superchargers. For example, blower arrangements have been disclosed in which a first blower and a second blower are placed in series, or a first blower and a second blower are placed in parallel. Also described are vehicles, construction machinery, and the like having a hybrid system that generates driving torque by means of an internal combustion engine and a motor generator.

An internal combustion engine with two relatively small superchargers placed in series or in parallel has the advantage of improved response and the ability to draw torque from a lower rpm range, etc. above the engine with only one large supercharger. However, with a dual-supercharger internal combustion engine, it is necessary to switch boost between (effectively) one supercharger and two superchargers in response to operating modes. A temporary decrease in boost may occur during the transition period from one to two (or two to one) superchargers. This reduction in boost can cause a reduction in torque. The reduction in torque is undesirable because it occurs at a level that the user can clearly feel, thus providing the user with a feeling of discomfort. Therefore, it is desirable to reduce the amount of torque reduction during the transition period when switching the number of superchargers to be used for boost control.

For example, Japanese Laid-Open Patent Application Publication No. 2010-190070 (JP 2010-190070) discloses a controller for an internal combustion engine system configured to control an internal combustion engine with a first supercharger and a second supercharger arranged in series. Each cylinder is equipped with a cylinder pressure sensor. The internal pressure of the cylinders during the exhaust process is obtained by means of this in-cylinder pressure sensor. Parameters associated with fluctuations in exhaust pressure that occur in response to changes in the state of supply of exhaust gases to the first and second superchargers are derived from the obtained in-cylinder pressure. Based on the obtained parameters, the pumping loss level is calculated. This is done by calculating the pumping loss before the supercharger changeover (the loss associated with the pumping action of the intake and exhaust piston) and the pumping loss during the supercharger changeover transition period. The injection amount for the torque adjustment is calculated and the fuel injection amount is increased (to increase the torque) based on the obtained pumping loss level. This suppresses fluctuations in torque caused by pumping losses.

However, even if the amount of torque is increased to compensate for the pumping torque loss, the adjusted output torque will not be sufficient to compensate for all of the torque loss. Additionally, in the system according to JP 2010-190070, it is necessary to provide a cylinder pressure sensor in each of the cylinders. This increases the cost of the system and requires significant modifications to the cylinders (or cylinder head).

Therefore, in a hybrid system in which driving torque is generated by an internal combustion engine and a motor generator, it has traditionally been desirable to provide a controller for the hybrid system that can correctly compensate for the lost torque caused by the internal combustion engine and further reduce the torque reduction. which causes discomfort for the user.

The essence of the invention

One embodiment of the present invention relates to a controller for a hybrid system configured to control a hybrid system configured to generate driving torque from an internal combustion engine and a motor generator. The operating condition detection unit of the controller detects the operating conditions of the internal combustion engine and the motor generator. The total required torque calculator of the controller calculates the total required torque based on the operating conditions. The controller's total required torque dividing unit divides the total required torque by the required combustion engine torque and the required motor torque. The total loss torque estimation unit of the internal combustion engine of the controller estimates the total loss torque of the internal combustion engine, which is the total amount of loss based on the actually generated driving torque relative to the target output torque of the internal combustion engine based on the required torque of the internal combustion engine. The motor compensation torque calculator of the controller calculates the motor compensation torque to be compensated by the motor generator based on the total loss torque of the combustion engine. The controller torque compensation execution unit adds the required motor torque and the motor compensation torque to determine the target motor output torque to be generated by the motor generator.

Therefore, the total torque loss of the internal combustion engine is compensated by the motor-generator using the compensating motor torque. While it is relatively difficult to compensate for the total loss torque of the internal combustion engine by the internal combustion engine, it is relatively easy to compensate for the total loss of the internal combustion engine by the motor generator. The total loss torque of the internal combustion engine generated by the internal combustion engine can thus be properly compensated by the motor generator, so that the torque reduction, which may cause discomfort to the user, can be further reduced.

According to another aspect of the present invention, an internal combustion engine may include a plurality of blowers, and blower switching means configured to change the number of blowers to be used for boost control. The controller may include a blower changeover unit configured to control the blower changeover means based on operating conditions and change the number of blowers to be used for boost control. The unit for estimating the total loss torque of the internal combustion engine can estimate the total loss torque of the internal combustion engine resulting from the boost reduction in the shift transition period. The switching transition period is a period of time from a state in which a boost reduction occurring immediately after changing the number of blowers by controlling the blower switching means until the target boost state is reached. The total loss torque of the internal combustion engine includes the loss torque during cooling, which is lost due to the increased amount of heat loss in the pistons and cylinders of the internal combustion engine caused by reduced boost.

Although the amount of boost reduction can be controlled to some extent, the occurrence of boost reduction is inevitable during the switching transition period immediately after the change in the number of boost control superchargers. As a result of this reduction in boost during the shift transition period, torque losses occur in the internal combustion engine. Various experiments and simulations have shown that torque losses due to reduced boost during the transient switching period of superchargers are loss (loss) on cooling, loss (loss) due to incomplete combustion, exhaust torque (gain), and pumping (loss) torque. losses. Among them, it was also found that the moment of loss on cooling is predominant (with the greatest proportion). According to the above-described aspect, the total loss torque of the internal combustion engine can be estimated more suitably because the total loss torque of the internal combustion engine includes the cooling loss torque.

According to another aspect of the present invention, the total loss moment of the internal combustion engine due to reduced boost, as estimated by the controller, includes the moment of loss due to incomplete combustion of fuel due to an increased amount of fuel not fully reacted with the air in the cylinders. Therefore, it seems possible to estimate a more correct value of the total loss torque of the internal combustion engine.

According to another aspect of the present invention, the cumulative loss torque of the internal combustion engine due to the boost reduction, as estimated by the controller, includes an exhaust loss torque that is amplified based on the reduced exhaust gas loss amount based on the exhaust gas flow rate from the cylinders. Therefore, it seems possible to estimate a more correct value of the total loss torque of the internal combustion engine.

According to another aspect of the present invention, the cumulative loss torque of the internal combustion engine due to reduced boost, as estimated by the controller, includes a pump loss torque that is lost based on the increased amount of pump loss due to the injection and discharge pumping action by the piston. Therefore, it seems possible to estimate a more correct value of the total loss torque of the internal combustion engine.

According to another aspect of the present invention, a hybrid system can be installed in a vehicle. The target output torque of the internal combustion engine generated by the internal combustion engine is transmitted to the front wheels of the vehicle. The target motor output torque generated by the motor generator is transmitted to the rear wheels of the vehicle. The hybrid system can be appropriately applied to such a vehicle.

Brief Description of Drawings

FIG. 1 is an illustrative view of an example of an internal combustion engine system (dual-blower internal combustion engine system) in a hybrid system having an internal combustion engine and a motor generator;

FIG. 2 is an illustrative view of an example of a vehicle equipped with a hybrid system having an internal combustion engine system and a motor generator system (example of transmitting the driving torque of an internal combustion engine and the driving torque of a motor generator to the rear wheels of the vehicle);

FIG. 3 is a diagram illustrating an example of the operations of the present embodiment for switching control from regulation with one blower (with only the first blower) to regulation with two blowers (with the first and second blowers), boost reduction that occurs during the transition period. switching, and compensation that occurs due to a decrease in boost;

FIG. 4 is a diagram illustrating an example of conventional operation in which the reduction in torque caused by the reduction in boost is not compensated for;

FIG. 5 is a diagram illustrating the total loss torque of an internal combustion engine;

FIG. 6 is a diagram illustrating the moment of loss due to incomplete combustion of fuel and is an example of a map of the moment of loss due to incomplete combustion of fuel for fuel that has not fully reacted with air in the cylinder in a low pressure environment;

FIG. 7 is a diagram illustrating a moment of loss due to incomplete combustion of fuel and is an example of a map of a moment of loss due to incomplete combustion of fuel for a fuel that has not fully reacted with air in a cylinder in a low temperature environment;

FIG. 8 is a flowchart illustrating an example of a controller processing procedure;

FIG. 9 is a flowchart illustrating details of the SB000 process (boost control switching process) in step S030 of the flowchart shown in FIG. eight;

FIG. 10 is a flowchart illustrating an example of a processing procedure (fuel injection process) of the controller;

FIG. 11 is a flowchart illustrating an example of a processing procedure (motor generator control process) of the controller; and

FIG. 12 is an illustrative view of an example vehicle in which driving torque for an internal combustion engine is transmitted to the front wheels of the vehicle and the driving torque of a motor generator is transmitted to the rear wheels of the vehicle, in contrast to the example vehicle equipped with a hybrid system shown in FIG. ... 2 (which is an example of the transmission of the drive torque of an internal combustion engine and the drive torque of a motor generator to the rear wheels of a vehicle).

Detailed description of the invention

Hereinafter, an example of the structure of the system 2 of the internal combustion engine (FIG. 1) will be described.

Thus, an embodiment for carrying out the present invention will be described with reference to the drawings. FIG. 1 shows an example of the structure of a system 2 of an internal combustion engine. The vehicle may be equipped with a hybrid system 1 having an internal combustion engine system 2 and a motor-generator system 3 (see FIG. 2). As an example of an internal combustion engine, an internal combustion engine 10 (for example, a diesel engine) installed in a vehicle will be described. An example of an internal combustion engine system 2 shown in FIG. 2 has two blowers including a first blower 31 and a second blower 32 arranged in parallel. However, the second blower 32 and the first blower 31 can also perform the boosting operation sequentially, for example, with the inlet bypass pipe 11CB and the inlet bypass valve 61.

Hereinafter, the system 2 of the internal combustion engine will be described, in order from the inlet side (upper portion in FIG. 1) to the outlet side (lower portion in FIG. 1), using FIG. 1. On the inlet side of the intake pipe 11A, intake air flow detecting means 21 (for example, intake air flow sensor), atmospheric pressure detecting means 22D (for example, pressure sensor) and intake air temperature detecting means 22E (for example, temperature sensor) may be provided. ... The intake air flow rate detecting means 21 outputs a signal according to the intake air flow rate of the internal combustion engine 10 to the controller 70. The atmospheric pressure detecting means 22D outputs a signal according to the atmospheric pressure to the controller 70, while the intake air temperature detecting means 22E air outputs a signal according to the temperature of the air sucked in by the internal combustion engine 10 (ambient temperature) to the controller 70. The outlet side of the intake pipe 11A is branched into two intake pipes 11B1, 11B2. The outlet side of the intake pipe 11A is connected to the intake sides of the intake pipes 11B1, 11B2.

The outlet side of the intake pipe 11B1 is connected to the intake side of the compressor 31A for the first supercharger 31 (first turbocharger). The outlet side of the inlet bypass pipe 11CB is connected to the middle portion of the inlet pipe 11B1. The outlet side of the compressor 31A is connected to the inlet side of the intake pipe 11C1. The downstream side of the intake pipe 11C1 is connected to the downstream side of the intake pipe 11C2 and is connected to the upstream side of the intake pipe 11D. The compressor 31A is rotated by the turbine 31B, so that the air sucked in through the intake pipe 11B1 is compressed and discharged (pumped) into the intake pipe 11C1.

The outlet side of the intake pipe 11B2 is connected to the intake side of the compressor 32A for the second supercharger 32 (second turbocharger). The outlet side of the compressor 32A forks into an inlet pipe 11C2 and an inlet bypass pipe 11CB. The first outlet side of the compressor 32A is connected to the inlet side of the intake pipe 11C2. The second outlet side of the compressor 32A is connected to the inlet side of the inlet bypass pipe 11CB. The downstream side of the intake pipe 11C2 is connected to the downstream side of the intake pipe 11C1 and is connected to the upstream side of the intake pipe 11D. The intake pipe 11C2 is provided with an intake air switching valve 62 configured to open and close the intake pipe 11C2 in response to a control signal from the controller 70. The outlet side of the intake bypass pipe 11CB is connected to the intake pipe 11B1. The inlet bypass pipe 11CB is provided with an inlet bypass valve 61 configured to open and close the inlet bypass pipe 11CB in response to a control signal from the controller 70.

The turbine 32B for rotationally driving the compressor 32A is rotated by the energy of the exhaust gas if the exhaust gas changeover valve 63 is open. The exhaust gas changeover valve 63 opens and closes the exhaust pipe 12B2 in response to a control signal from the controller 70. The controller 70 opens one of the intake air changeover valve 62 or the intake bypass valve 61 and closes the other when the turbine 32B is driven while the exhaust gas changeover valve 63 is open. The controller 70 closes the intake air changeover valve 62 and the intake bypass valve 61 when the exhaust gas changeover valve 63 is closed.

Compressor 32A compresses air drawn in through intake pipe 11B2 and discharges (pumps) it into intake pipe 11C2 when compressor 32A is driven by turbine 32B with intake air changeover valve 62 open and intake bypass valve 61 closed. On the other hand, compressor 32A compresses the air sucked in through the intake pipe 11B2 and discharges (pumps) it into the intake bypass pipe 11CB when the compressor 32A is driven by the turbine 32B with the intake air switching valve 62 closed and the intake bypass valve 61 open.

The inlet side of the inlet pipe 11D is connected to the outlet side of the inlet pipe 11C1 and the outlet side of the inlet pipe 11C2. The downstream side of the intake pipe 11D is connected to the downstream side of the intake manifold 11E. The intake manifold 11E is provided with an intake manifold detecting means 22A (for example, a pressure sensor) for detecting the boost pressure in the intake manifold 11E, and an intake manifold detecting means 28A (for example, a temperature sensor) for detecting the temperature of the intake air in the intake manifold 11E. Intake manifold detecting means 22A outputs a signal corresponding to the intake air pressure (blown intake air) of the intake manifold 11E to the controller 70. Intake manifold detecting means 28A outputs a signal according to the intake air temperature of the intake manifold 11E to the controller 70.

The outlet side of the intake manifold 11E is connected to the corresponding cylinders of the internal combustion engine 10.

The internal combustion engine 10 includes a plurality of cylinders, and the cylinders are provided with injectors 43A to 43H, respectively. Fuel is supplied from the high pressure fuel supply system 42, through a fuel line, to injectors 43A-43H. Injectors 43A-43H are driven in response to a control signal from controller 70 to inject fuel into each of the cylinders.

Fuel is supplied to the high pressure fuel supply system 42 from a fuel pressure regulating pump 41, which is driven in accordance with a control signal from controller 70. The high pressure fuel supply system 42 is provided with fuel pressure detecting means 23 (for example, a pressure sensor) for detecting the fuel pressure in the high-pressure fuel supply system 42. The fuel pressure detecting means 23 outputs a signal according to the detected fuel pressure to the controller 70. The controller 70 controls the fuel pressure regulating pump 41 so that the fuel pressure, based on the detected signal from the fuel pressure detecting means 23, becomes the target fuel pressure.

The internal combustion engine 10 is provided with rotation detection means 25 (for example, a rotation sensor), a coolant temperature detection means 24 (for example, a temperature sensor), and the like. The rotation detecting means 25 is configured to output a signal in accordance with the rotational speed of the crankshaft of the internal combustion engine 10 (i.e., the engine speed) to the controller 70. The coolant temperature detecting means 24 is configured to detect the temperature of the coolant circulating in the engine internal combustion, and output a signal according to the detected temperature to the controller 70.

The exhaust sides of the exhaust manifolds 12A1, 12A2 are connected to the exhaust side of the internal combustion engine 10. The inlet side of the exhaust pipe 12B1 is connected to the outlet side of the exhaust manifold 12A1. The inlet side of the exhaust pipe 12B2 is connected to the outlet side of the exhaust manifold 12A2. The outlet side of the exhaust pipe 12B1 is connected to the inlet side of the turbine 31B for the first blower 31. The outlet side of the exhaust pipe 12B2 is connected to the inlet side of the turbine 32B for the second blower 32. The exhaust pipe 12B2 is provided with an exhaust gas switching valve 63, which opens and closes the exhaust pipe 12B2 in response to a control signal from controller 70. Exhaust bypass pipe 12BB, which leads exhaust gas in exhaust pipe 12B2 to exhaust pipe 12B1 when exhaust gas switching valve 63 is closed, is connected to exhaust pipe 12B1 and exhaust pipe 12B2.

The inlet side of the exhaust pipe 12C1 connects to the outlet side of the turbine 31B for the first blower 31, and the outlet side of the exhaust pipe 12C1 (exhaust pipe 12D downstream of the junction with the exhaust pipe 12C2) connects to the inlet side of the catalytic converter 51. Inlet side of the exhaust pipe 12C2 connects to the outlet side of the turbine 32B for the second blower 32, and the outlet side of the exhaust pipe 12C2 connects to the middle of the exhaust pipe 12C1. The exhaust pipe 12C1 is provided with an exhaust gas pressure detecting means 22B (for example, a pressure sensor) to detect the exhaust gas pressure in the exhaust pipe 12C1, an exhaust gas temperature detecting means 26 (for example, a temperature sensor) to detect the temperature of the exhaust gases in the exhaust pipe 12C1. The exhaust gas pressure detecting means 22B outputs a signal according to the detected pressure to the controller 70. The exhaust gas temperature detecting means 26 outputs a signal according to the detected temperature to the controller 70.

The turbine 31B for the first blower 31 is provided with an adjustable nozzle 31C adapted to regulate the flow rate of the exhaust gas, which causes the turbine 31B to rotate. The adjustable nozzle 31C is driven by a nozzle driving means 31D (for example, an electric motor), which is triggered in response to a control signal from the controller 70. The nozzle opening detection means 31E (for example, a rotation angle sensor) outputs a signal to the controller 70 in accordance with the operating the condition of the nozzle driving means 31D (in this case, the angle of rotation of the electric motor) based on the opening of the variable nozzle 31C. The controller 70 serves to control the nozzle driving means 31D so that the opening degree of the variable nozzle 31C obtained based on the detected signal from the nozzle opening detection means 31E will be the target nozzle opening value. Likewise, the second blower 32 may include an adjustable nozzle 32C for turbine 32B, nozzle actuation means 32D, and nozzle opening detection means 32E.

The outlet side of the catalytic converter 51 is connected to the inlet side of the DPF (Diesel Particulate Filter) 52 (for example, a fine particle filter). The catalytic converter 51 oxidizes and purifies HC (hydrocarbons) and CO (carbon monoxide) in the exhaust gas of the internal combustion engine 10.

The outlet side of the DPF 52 is connected to the inlet side of the urea SCR 53. The DPF 52 traps fine particles in the exhaust gas. The DPF 52 is provided with a differential pressure detecting means 22C (e.g., a differential pressure sensor) configured to detect a differential pressure between the inlet and outlet sides of the DPF 52. The differential pressure detecting means 22C outputs a signal in accordance with the pressure difference between the inlet and outlet sides of the DPF 52. controller 70. The controller 70 may estimate the amount of fine particles deposited on the DPF 52 from the differential pressure based on the detected signal from the differential pressure detecting means 22C.

Urea SCR 53 uses urea injected from a urea water addition valve (not shown) to reduce and purify NOx (nitrogen oxides) in the exhaust gas.

An accelerator pedal depression amount detecting means 27 (for example, an accelerator pedal depression angle sensor) is provided on the accelerator pedal. The accelerator pedal depression amount detecting means 27 outputs a signal in accordance with the accelerator depression amount by the driver to the controller 70.

The controller 70 includes a CPU 71 (CPU), RAM 72 (RAM), memory means 73, EEPROM 74 (EEPROM), timer 75, etc. RAM 72, memory facility 73, EEPROM 74, timer 75, etc. are connected to the CPU 71 via various buses. The memory means 73 may be, for example, a storage device such as a Flash ROM, and may store programs, data, and the like. to carry out the processes described below. The CPU 71 includes an operating condition detecting unit 71A, a total required torque calculating unit 71B, a total required torque dividing unit 71C, an internal combustion engine total loss torque estimating unit 71D, a motor compensation torque calculating unit 71E, a torque compensation performing unit 71F moment, the blower switching unit 71G, and the like. Details of the various parts of the CPU 71 will be described later.

As shown in FIG. 2, the controller 70 outputs control signals for controlling the clutch and disengagement of the first clutch 15A and the second clutch 15B. The controller 70 is configured to detect the operating condition of the motor generator 80, the inverter 81, and the battery 82. The controller 70 outputs control signals to the motor generator 80, the inverter 81, and the battery 82.

A vehicle equipped with a hybrid system 1 having an internal combustion engine system 2 and a motor-generator system 3 (FIG. 2)

As shown in FIG. 2, the vehicle described in the present embodiment is equipped with a hybrid system 1 configured to generate driving torque by an internal combustion engine system 2 having an internal combustion engine 10 (see FIG. 1) and a motor-generator system 3, having a motor generator 80. The vehicle shown in FIG. 2, has driving wheels RR, RL, driven wheels FR, FL, differential 17, transmission 16, second clutch 15B, motor generator 80, first clutch 15A, internal combustion engine 10, controller 70, inverter 81, battery 82 etc. The controller 70 is adapted to detect the rotation speed of the internal combustion engine 10 based on the detected signal from the rotation detection means 25. The controller 70 is adapted to detect the rotation speed of the motor generator 80 based on the detected signal from the rotation detection means 80A. The controller 70 is adapted to detect the rotation speed of the input shaft of the transmission 16 based on the detected signal from the rotation detection means 16A. The controller 70 may switch the first clutch 15A and the second clutch 15B between an engaged state, a disengaged state, and a semi-engaged state (slip state).

When the driving torque is generated by the motor generator 80, the power output from the battery 82 is converted into motor driving power by the inverter 81 to drive the motor generator 80. When the motor generator 80 is operating in a regenerative mode, the power generated by means of the motor generator 80, is converted into charging power by means of the inverter 81, which charges the battery 82.

Although not shown in the drawings, the motor generator 80, the inverter 81, and the battery 82 are provided with various detection means adapted to detect their respective operating conditions. The controller 70 can detect the operating conditions of the motor generator 80, the inverter 81, and the battery 82. Although not shown, the motor generator 80, the inverter 81, and the battery 82 are provided with various actuators and control circuits. The controller 70 can control the operations of the motor generator 80, the inverter 81, and the battery 82. In other words, the controller 70 controls the internal combustion engine 10, the motor generator 80, the inverter 81, the battery 82, the first clutch 15A and the second clutch 15B on based on the operating conditions of the internal combustion engine 10, the motor generator 80, the inverter 81, and the battery 82.

For example, when the driving torque to be transmitted to the driving wheels RR, RL is generated only by the internal combustion engine 10, the controller 70 controls the internal combustion engine 10 to generate the driving torque. The controller 70 controls the first clutch 15A and the second clutch 15B to be engaged. The controller 70 controls the inverter 81 so that the driving torque is not generated by the motor generator 80. On the other hand, when the driving torque to be transmitted to the driving wheels RR, RL is generated by the internal combustion engine 10 and the motor generator 80 , the controller 70 controls the internal combustion engine 10 to generate a driving torque. The controller 70 controls the first clutch 15A and the second clutch 15B to be engaged. The controller 70 controls the inverter 81 so that the driving torque is also generated by the motor generator 80. On the other hand, when the driving torque to be transmitted to the driving wheels RR, RL is generated only by the motor generator 80, the controller 70 stops the engine 10 internal combustion and controls the first clutch 15A to be in the open state. The controller 70 controls the second clutch 15B to be engaged. The controller 70 controls the inverter 81 so that the driving torque is generated by the motor generator 80.

Example of Switching Boost Control and Decrease in Boost Pressure and Torque During a Transient Switching Period (Figs. 3-7)

FIG. 3 shows an example of switching the boost control from one turbocharger (boosting with only the first blower 31 (see FIG. 1)) to two turbochargers (boosting with the first blower 31 and the second blower 32 (see FIG. 1)). The example shown in FIG. 3 shows that boost control is performed with a single turbocharger up to time Ta. The conditions for switching from one to two turbochargers are set at time Ta. The boost control is then performed with the two turbochargers after the Tb time. The time from Ta to Tb is the changeover time when the system switches from one turbocharger to two. FIG. 3 illustrates the operation of the present embodiment in which the motor / generator compensates for the torque drop when shifting from one turbocharger to two. FIG. 4 is a diagram illustrating conventional operation without compensation by means of a motor generator. FIG. 5 is a diagram illustrating the total loss torque of an internal combustion engine that causes a torque reduction when switching from one turbocharger to two turbochargers.

As shown in FIG. 3, before time Ta, controller 70 determines that boost control should be performed with a single turbocharger. As shown in FIG. 1 and 3, in this case, the controller 70 closes the inlet bypass valve 61, the intake air changeover valve 62, and the exhaust gas changeover valve 63. As a result, the exhaust gas does not flow into the turbine 32B of the second blower 32. Therefore, the second blower 32 does not pressurize, but is only pressurized by the first blower 31.

As shown in FIG. 3, at time Ta, the controller 70 determines that the changeover conditions for switching from single-turbo boost control to dual-turbo boost control have been met. As shown in FIG. 1 and 3, in this case, the controller 70 temporarily connects the second blower 32 and the first blower 31 in series in order to reduce or prevent the boost reduction. In this case, the controller 70 opens the intake bypass valve 61, closes the intake air changeover valve 62, and opens the exhaust gas changeover valve 63. From the time Ta until the switching time has elapsed (before the time Tb is reached), this state is maintained and the second blower 32 and the first blower 31 are connected in series so as to allow the second blower 32 and the first blower 31 to be pressurized. ...

As shown in FIG. 3, after the time Tb has been reached, that is, when the shift time has elapsed from the time Ta, the controller 70 determines that the boost control is to be performed with the two turbochargers. Referring to FIG. 1 and 3, in this case, the controller 70 closes the inlet bypass valve 61, opens the intake air changeover valve 62, and opens the exhaust gas changeover valve 63. In this case, the controller 70 uses the first blower 31 and the second blower 32 in parallel, so as to allow the second blower 32 and the first blower 31 to be pressurized.

As shown in FIG. 3, the time Ta, the time Tb and the time Tc pass in this order. The time from time Ta to time Tc is the transition time. At time Ta, the changeover from one turbocharger to two turbochargers begins. During Tb, the changeover to two turbochargers is completed. The time additionally passes from the time Tb and reaches the time Tc. During the transient time (corresponding to the switching transition period), the turbine speed of the second supercharger is still insufficiently increased, thereby causing a drop in boost pressure to occur. With this decrease in boost pressure, the output torque of the internal combustion engine 10 will also be reduced. While the user will almost never feel a decrease in boost pressure, he / she will feel a decrease in torque output as this forces the vehicle to jerk. As will be described below, by the controller process described in the present embodiment, this decrease in output torque will be reduced to a level that the user cannot easily feel.

As shown by the boost pressure section in FIG. 3, a decrease in boost pressure occurs during a transient, the time between the time Ta and the time Tc. Therefore, although the "target output torque of the internal combustion engine" section shown in FIG. 3, which is the target driving torque generated by the internal combustion engine is constant between the time Ta and the time Tc, in reality, a decrease in torque will occur as shown as the section "driving torque actually generated by the internal combustion engine" shown in FIG. 3 due to a decrease in boost pressure. The times Td and Te shown in FIG. 3 is the time between the time Ta and the time Tc, which is the time of the turbo 1 to turbo 2 changeover state. The time Td is the time at which the driving torque actually generated in the internal combustion engine 10 starts to decrease. The time Te is the time at which the reduction in the driving torque actually generated in the internal combustion engine 10 ends.

Hereinafter, the decrease in torque, which is shown by the decrease in the section "Drive Torque Actually Generated in the Internal Combustion Engine" shown in FIG. 3, will be called the total moment ДTQ of losses of the internal combustion engine. The decrease in the output torque in this case occurs because the torque of the internal combustion engine is lower due to the decrease in the boost pressure, but is not compensated for by the torque generation by the motor generator. Therefore, DTQ is called the "total loss torque of the internal combustion engine". In the present embodiment, as will be described later, the total loss torque DTQ of the internal combustion engine is compensated by the motor generator. More specifically, "compensation motor torque" (see FIG. 3) is determined, and then a "target motor output torque obtained by adding the compensation motor torque to the required motor torque" (see FIG. 3) is obtained. The motor generator is then controlled to achieve a specific target motor torque output. As a result, as shown at the bottom in FIG. 3, the reduction (DQ) of the drive torque actually generated by the combustion engine and the motor generator relative to the total required torque (total required torque) is further reduced. In contrast, FIG. 4 shows a conventional operation in which the motor compensation torque to compensate for the total loss torque of the internal combustion engine is not determined. Therefore, the decrease (DQz) in the drive torque actually generated by the combustion engine and the motor generator is significantly larger relative to the total required torque (total required torque), as shown at the bottom in FIG. 4. As a result, the user may feel a decrease in torque.

The inventors carried out numerous experiments and simulations and analyzed factors to determine the total loss torque DTQ of the internal combustion engine. The inventors then found that the total loss moment DTQ of the internal combustion engine is the sum of the cooling loss moment, the exhaust loss moment, the pumping loss moment and the moment of loss due to incomplete combustion of the fuel, as shown in FIG. 5. As can be seen in FIG. 5, the moment of loss during cooling is predominant in (a much larger proportion) of the total moment DTQ of losses of the internal combustion engine.

Cooling loss is the torque that is lost due to the amount of heat (heat loss) taken from the cylinders and pistons. This can happen when the fuel injected into the cylinders hits the cylinders and pistons before being fully atomized when the boost pressure rises. The injected fuel can remove heat from the cylinders and pistons. The method for calculating the cooling loss torque can be based on the coolant temperature and the boost pressure. This loss can be determined by obtaining and analyzing various experimental data regarding the actual coolant temperature and boost pressure of the internal combustion engine. More specifically, the increase in cooling loss can be determined by subtracting the cooling loss before the boost control is switched from the cooling loss during the transient. The controller can estimate the heat loss moment that is lost due to heat loss to the pistons and cylinders of the internal combustion engine based on the increased amount of heat loss caused by the decrease in boost.

The exhaust loss torque is the torque that is "boosted" by decreasing the exhaust gas pressure resulting from the decrease in boost pressure. The pressure loss characteristics for the exhaust gas pressure loss are largely determined by hardware such as that shown in FIG. 1 through which the exhaust gas flows from the catalytic converter 51 until it is vented to the atmosphere. The exhaust gas pressure in the exhaust manifold 12A1 of the internal combustion engine 10 can be determined from the atmospheric pressure detected by the atmospheric pressure detecting means 22D, the pressure loss characteristics described above, the differential pressure detected by the differential pressure detecting means 22C, and the opening of the variable nozzle 31C. Additionally, the exhaust loss point can be determined from the pressure of the exhaust gas in the exhaust manifold 12A1 of the internal combustion engine 10. More specifically, the amount of the exhaust loss moment that has been reduced can be determined by subtracting the exhaust loss moment before the boost control changeover from the exhaust loss moment during the transition period. As will be described later, in the exhaust gas loss based on the flow rate of the exhaust gas from the cylinders of the internal combustion engines, the controller can estimate the exhaust loss moment enhanced based on the reduced amount of exhaust gas loss resulting from the boost reduction.

Pumping loss moment is the loss of torque determined by inlet side pressure, outlet side pressure, and piston top surface area. This determination is made when the piston performs a pumping action in which the piston draws intake air from the intake manifold and supplies exhaust gas under pressure to the exhaust manifold. Since the amount of suction force increases when the boost pressure decreases, the pumping loss increases when the boost pressure decreases. In other words, the amount of increase in the pumping loss moment can be determined by subtracting the pumping loss moment before the boost control is switched from the pumping loss moment during the transient. As will be described later, by using the pumping loss based on the pumping action for intake and exhaust by the piston of the internal combustion engine, the controller can estimate the pumping loss moment amplified based on the increased pumping loss amount resulting from the boost reduction.

Moment of loss due to incomplete combustion of fuel, which is a loss due to a portion of the fuel injected into the cylinders. More specifically, it is the part that has not fully reacted with air (unburned fuel) in low pressure or low temperature environments. For example, the moment of loss due to incomplete combustion of the fuel depends on the rotational speed and injection volume for the internal combustion engine. The characteristic of the moment of loss due to incomplete fuel combustion is prepared for each pressure level in the intake manifold. Thus, the moment of loss due to incomplete combustion of the fuel (low pressure environment) in the low pressure environment can be determined (estimated).

For example, as shown in FIG. 6, the moment of loss due to incomplete combustion of the fuel depends on the characteristics of the rotational speed (N *) and the injection volume (Q *) for the internal combustion engine. The characteristic of the moment of loss due to incomplete combustion of the fuel (low pressure environment) is prepared for each of the boost pressures (a1, a2, a3, a4, etc.) in the intake manifold and is stored in the memory. The controller determines (estimates) the moment of loss due to incomplete fuel combustion (low pressure environment) from the characteristics of the moment of loss due to incomplete fuel combustion and the operating conditions of the internal combustion engine. The operating conditions of the internal combustion engine can be, for example, the rotational speed, the injection volume for the internal combustion engine, and the boost pressure at the intake manifold.

For example, as shown in FIG. 7, the characteristic of the torque (E *) loss due to incomplete combustion of the fuel depends on the rotational speed (N *) and the injection volume (Q *) for the internal combustion engine. The characteristic of the moment of loss due to incomplete combustion of the fuel (low temperature environment) is prepared for each temperature (t1, t2, t3, t4, etc.) in the intake manifold and is stored in the storage means. The controller can determine (estimate) the moment of loss due to incomplete combustion of fuel (low temperature environment) from the moment of loss due to incomplete combustion of fuel (low temperature environment) and the operating conditions of the internal combustion engine. The operating conditions of the internal combustion engine can be, for example, the rotational speed, the injection volume for the internal combustion engine, and the temperature in the intake manifold. The controller can then determine (estimate) the moment of loss due to incomplete fuel combustion, for example, by adding the moment of loss due to incomplete fuel combustion (low pressure environment) and the moment of loss due to incomplete fuel combustion (low temperature environment).

Controller 70 Processing Routines (FIGS. 8-11)

Hereinafter, examples of the processing procedures of the controller 70 (CPU 71) will be described with reference to the flowcharts shown in FIG. 8-11. The process shown in FIG. 8 begins, for example, at predetermined time intervals (eg, at intervals of several [ms] to several tens [ms] milliseconds). The controller 70 (CPU 71) proceeds to step S010.

In the next step S010, the controller 70 acquires and stores physical quantities based on the detected signals from the various detection means, and advances the process to the next step S015 to process the input signal. For example, the controller 70 receives the current intake air flow, intake air temperature (ambient temperature), intake air pressure (atmospheric pressure), intake manifold boost pressure, intake manifold temperature, coolant temperature, combustion engine speed, fuel pressure, fuel injection volume, injection time interval, exhaust gas pressure, exhaust gas temperature, opening value of the variable nozzle of the first blower, opening value of the variable nozzle of the second blower, differential pressure DPF, pressure of the accelerator pedal, battery state, inverter state, motor generator state etc. The controller 70 accordingly stores them as the current intake air flow rate, the current ambient temperature, the current atmospheric pressure, the current intake manifold boost pressure, the current intake manifold temperature, the current coolant temperature, the current rotational speed of the internal combustion engine, the current fuel pressure, current fuel volume, current injection time, current exhaust gas pressure, current exhaust gas temperature, current opening value of the first nozzle, current opening value of the second nozzle, current differential pressure, current value of accelerator pedal depression, current state of the battery, current state of the inverter, the current state of the motor generator, etc. The physical quantities to be stored in the memory of the controller 70 should not be limited to these quantities.

The controller 70 (CPU 71) includes an operating condition detecting unit 71A that executes the processing in step S010. The operating condition detecting unit 71A is used to detect the operating conditions of the internal combustion engine and the motor-generator (as well as the battery and the inverter).

In step S015, the controller 70 calculates the total required torque based on the rotational speed of the internal combustion engine, the rotational speed of the motor generator 80, the rotational speed of the transmission 16, and the accelerator pedal depression amount. The controller 70 then advances the process to step S020. For example, the memory means stores a characteristic of the total required torque in which the required torque is set in accordance with the rotational speed (of the internal combustion engine, motor generator and transmission) and the amount of accelerator pedal depression. The controller 70 determines (calculates) the total required torque desired by the driver from the characteristic of the total required torque, the rotational speed and the amount of accelerator pedal depression. The procedure for determining the total torque requirement is already a known procedure and therefore will not be described.

The controller 70 (CPU 71) includes a total required torque calculating unit 71B which executes the process in step S015 (see FIG. 1). The total required torque calculating unit 71B calculates the total required torque, which is the sum of the required torque, based on the operating conditions of the internal combustion engine and the motor generator.

In step S020, the controller 70 divides the obtained total required torque by the required combustion engine torque to be generated in the internal combustion engine and the required motor torque to be generated in the motor generator. The controller 70 then advances the process to the next step S025. The division procedure is already a known procedure and therefore will not be described.

The controller 70 (CPU 71) includes a total required torque dividing unit 71C (see FIG. 1) for executing the process in step S020. The total demanded torque dividing unit 71C divides the total demanded torque by the demanded torque of the internal combustion engine, which is the demanded torque of the internal combustion engine, and the demanded torque of the motor, which is the demanded torque of the motor generator.

In step S025, the controller 70 calculates a target output torque of the internal combustion engine. The target output torque of the internal combustion engine is the target drive torque to be generated by the internal combustion engine based on the required torque of the internal combustion engine. The controller 70 then advances the process to the next step S030. The procedure for calculating the target torque output of the internal combustion engine is already a known procedure and therefore will not be described.

In step S030, the controller 70 executes the [SB000: Boost Control Switching Process] shown in FIG. 9, and then advances the process to step S035. When the controller 70 performs step S030 as shown in FIG. 8, it advances the process to step SB010 shown in FIG. nine.

SB000: Boost Control Switching Process (Fig. 9)

In step SB010, as shown in FIG. 9, controller 70 determines whether or not it is currently performing boost control with a single turbocharger (the only boost control in which boost is performed only by the first supercharger). If performing boost control with one turbocharger (Yes), controller 70 advances to step SB020. If not performing boost control with one turbocharger (No), controller 70 advances to the next step SB110. The SB000 process shown in FIG. 9 is a known process. This SB000 process is an example of a switchover process from single turbo boost control (single boost control in which boost is only provided by the first supercharger) to dual turbo boost control (dual boost control in which boost is performed by the first and second superchargers) ... The details of step SB110, which is a changeover process from dual turbo boost control to single turbo boost control, will not be described.

As the process advances to the next step SB020, the controller 70 determines whether or not the conditions for switching from single turbo boost control to dual turbo boost control have been set based on the operating conditions of the internal combustion engine. If the switching conditions have been set (Yes), the controller 70 advances the process to the next step SB030. If the switching conditions have not been set (No), the controller 70 advances the process to the bypass step for step SB060A.

When the process advances to step SB030, the controller 70 determines whether or not the switch timer has been activated (see FIG. 3). If enabled (Yes), the controller 70 advances the process to the next step SB050. If not activated (No), the controller 70 advances the process to the substage of step SB040.

When the process advances to step SB040, the controller 70 turns on the switch start flag and activates the switch timer. The process then advances to the next step SB050.

When the process advances to step SB050, the controller 70 determines whether the switching timer indicates a time before the switching time (see FIG. 3). When the switch timer indicates the time before the switch time (Yes), the controller 70 advances the process to the next step SB060B. When the switch timer indicates the same time or advance time for the switch time (No), the controller 70 advances the process to this bypass step for step SB060C. The values for the switching times can be set to the correct values through various experiments, etc. using an actual vehicle.

When the process advances to step SB060A, boost control with one turbocharger is maintained (continued) in which boost is performed only by the first supercharger. The controller 70 controls the intake bypass valve 61 to be closed, the intake air changeover valve 62 to be closed, and the exhaust gas changeover valve 63 to be closed (see FIG. 2). The controller 70 then advances the process to the next step SB070A.

In step SB070A, the controller 70 stops and initializes the switch timer, ends the process shown in FIG. 9 and advances the process to S035 shown in FIG. eight.

When the process advances to step SB060B, switching from single turbo boost control to dual turbo boost control is in progress (switching transition in FIG. 3). During this changeover, the boost operation is performed by a second blower and a first blower placed in series. The controller 70 controls the inlet bypass valve 61 for opening, the intake air switching valve 62 for closing, the exhaust gas switching valve 63 for opening (see FIG. 3), completes the process shown in FIG. 9, and then advances the process to step S035 shown in FIG. eight.

When the process advances to step SB060C, the boost control with the two turbochargers is maintained (continues) and the boost operation is performed by the first and second superchargers arranged in parallel. The controller 70 regulates the intake bypass valve 61 to close, the intake air changeover valve 62 to open, the exhaust gas changeover valve 63 to open (see FIG. 3), and advances to step SB070C.

In step SB070C, the controller 70 stops and initializes the switch timer, ends the process shown in FIG. 9 and advances the process to S035 shown in FIG. eight.

The controller 70 (CPU 71) includes a blower switching unit 71G that performs a process [SB000: boost control switching process] shown in FIG. 9. The blower switch unit 71G is configured to switch the number of blowers to be used for boost control. This is done by controlling the blower switching means (intake bypass valve, intake air changeover valve and exhaust gas changeover valve) based on the operating conditions (of the internal combustion engine). The blower switching means can be, for example, an intake bypass valve, an intake air changeover valve, and an exhaust gas changeover valve.

Returning to the description with reference to FIG. 8, the controller 70 determines in step S035 whether the switching start flag is on (the flag is on in step SB040 in FIG. 9). If the switching start flag was turned on (Yes), the controller 70 advances the process to step S040. If not (No), the controller 70 advances the process to step S050.

When the process has advanced to step S040, the controller 70 determines whether the current time is Ta shown in FIG. 3. If so, controller 70 maintains the operating conditions of the combustion engine and motor generator prior to switching. Operating conditions can be, for example, intake manifold boost pressure before shifting and intake manifold temperature before shifting. The controller 70 then advances the process to step S045.

For example, the controller 70 may store the current intake air flow rate as the intake air flow rate before switching. Likewise, the controller 70 can store the current ambient temperature as the air temperature before the changeover, the current atmospheric pressure as the atmospheric pressure before the changeover, the current intake manifold boost pressure as the intake manifold boost pressure before the changeover, and the current intake manifold temperature as the temperature before switching in the intake manifold. The controller 70 can also store the current coolant temperature as the coolant temperature before switching, the current rotation speed of the internal combustion engine as the rotation speed of the internal combustion engine before switching, the current fuel pressure as the fuel pressure before switching, the current fuel volume as the fuel volume before switching and the current injection timing as the pre-shift injection timing. The controller 70 may further store the current exhaust gas pressure as the exhaust gas pressure before switching, the current exhaust gas temperature as the exhaust gas temperature before switching, the current opening amount of the first nozzle as the opening amount of the first nozzle before switching, the current opening amount of the second nozzle as the opening amount of the second nozzle before switching, the current differential pressure as the differential pressure before switching, and the current amount of depression of the accelerator pedal as the amount of depression of the accelerator pedal before switching. The controller 70 may also store the current state of the battery as the state of the battery before switching, the current state of the inverter as the state of the inverter before switching, and the current state of the motor generator as the state of the motor generator before switching. The different physical quantities stored in step S040 will be used in evaluating the different loss times in steps S060 to S080. The physical quantities to be stored as the "before switching" quantity need not be limited to the quantities described above.

In step S045, the controller 70 starts the switching transition timer (see FIG. 3) and advances the process to step S050.

When the process advances to step S050, the controller 70 determines whether or not the switch transition timer has been activated. If the switch transition timer is activated (Yes), the controller 70 advances the process to step S055. If the switch transition timer is not activated (NO), the controller 70 advances the process to step S090.

When the process advances to step S055, the controller 70 determines whether the switching transition timer is before the transition time (switching transition) (see FIG. 3). If before the transient time (YES), the controller 70 advances the process to step S060. When the over time is in the switching transient state, the controller 70 advances the process to step S090. The value of the transient time (switching transition period) is set to correspond to the time (period) when a decrease in boost pressure and output torque occurs. As shown in FIG. 3, this occurs at a predetermined time during and after the switch. The transient time value is set to an appropriate value based on various experiments using actual vehicles, etc. For example, the transient time can be approximately 1–2 seconds.

When the process advances to step S090, the controller 70 stops and initializes the switch transition timer. Additionally, the controller 70 initializes the total loss torque of the internal combustion engine and advances the process to step S110.

When the process has advanced to step S060, the controller 70 judges the cooling loss point (see FIG. 5) and advances the process to step S065. For example, the controller 70 may estimate a cooling loss point from a value map or the like. according to the coolant temperature and boost pressure. Map values can be determined, for example, through various experiments and various simulations using actual vehicles. The controller 70 evaluates the cooling loss moment (before the shift) using said map, the boost pressure before the shift (the boost pressure before the shift in the intake manifold), the coolant temperature before the shift, etc. The controller 70 estimates the (current) cooling loss with said map, current boost pressure (current intake manifold boost pressure), current coolant temperature, and so on. The controller 70 then subtracts the refrigeration loss (pre-changeover) from the (current) refrigeration loss to estimate the increase in refrigeration loss relative to the pre-changeover state. However, the method for evaluating the increase in the point of cooling loss is not limited to the above method.

In step S065, the controller 70 judges the timing of the exhaust loss (see FIG. 5) and advances the process to step S070. For example, the controller 70 may estimate an exhaust loss moment from the differential pressure DPF and the value map in accordance with the exhaust gas flow rate and the exhaust gas pressure (pressure in the exhaust manifold), etc. Map values can be determined, for example, through various experiments and various simulations using actual vehicles. The controller 70 can estimate the moment of the exhaust loss (before switching) using said map, the exhaust gas flow rate before switching (calculated from the intake air flow rate before switching and the exhaust gas temperature before switching), the exhaust gas temperature before switching, differential pressure before switching, opening nozzles before switching, etc. Additionally, the controller 70 estimates the (current) exhaust loss moment using said map, the current exhaust gas flow rate (calculated from the current intake air flow rate and the current exhaust gas temperature), the current exhaust gas pressure, the current differential pressure, the current nozzle opening, etc. etc. The exhaust gas pressure before the changeover (pressure in the exhaust manifold) can be estimated from the exhaust gas pressure before the changeover (pressure downstream of the turbine), the opening of the nozzle before the changeover, etc. The controller 70 may then estimate the reduction in the exhaust loss moment by subtracting the (current) exhaust loss moment from the exhaust loss moment (before the shift). However, the method for evaluating the reduction of the exhaust loss torque is not limited to the above-described method.

In step S070, the controller 70 estimates the moment of pumping loss (see FIG. 5) and advances the process to step S075. For example, controller 70 may estimate pumping loss moment from a value map in accordance with boost pressure and exhaust gas pressure (exhaust manifold pressure), boost pressure, exhaust gas pressure, and piston top surface area. Map values can be determined, for example, through various experiments and various simulations using actual vehicles. The controller 70 can estimate the moment of pumping loss (before shifting) using a map, boost pressure before shifting (boost pressure before shifting in the intake manifold), exhaust gas pressure before shifting, boost pressure before shifting (boost pressure before shifting in intake manifold), pressure exhaust gas before switching, piston top area, etc. Additionally, controller 70 may estimate the (current) pumping loss moment using a map, current boost pressure (current intake manifold boost pressure), current exhaust gas pressure, piston top area, and so on. Additionally, the exhaust gas pressure before the changeover (pressure in the exhaust manifold) can be estimated from the exhaust gas pressure before the changeover (pressure downstream of the turbine) and the amount of opening of the nozzle before the changeover, etc. Then, the controller 70 may estimate the increase at the moment of pumping loss by subtracting the moment of the pumping loss (before the changeover) from the (current) moment of the pumping loss. The method for evaluating the increase at the point of pumping loss is not limited to the above-described method.

In step S075, the controller 70 judges the timing of the loss due to incomplete combustion of the fuel (see FIGS. 5-7) and advances the process to step S080. For example, the controller 70 may estimate the moment of loss due to incomplete combustion of the fuel from the value map (see Fig. 6 and Fig. 7) in accordance with the rotational speed and the amount of injection. The value of the map can be determined through various experiments and various simulations using actual vehicles. The controller 70 can estimate the moment of loss due to incomplete fuel combustion (before the shift) using a map (see Figs. 6 and 7), the boost pressure before the shift in the intake manifold, the temperature before the shift in the intake manifold, the rotational speed before the shift, the injection volume before switching, etc. Additionally, the controller 70 can estimate the (current) moment of loss due to incomplete fuel combustion using a map (see FIGS. 6 and 7), current intake manifold boost pressure, current intake manifold temperature, current rotational speed, current injection volume, etc. .d. Then, the controller 70 may estimate the increase in the moment of loss due to incomplete fuel combustion by subtracting the moment of loss due to incomplete fuel combustion (before switching) from the (current) moment of loss due to incomplete fuel combustion. The method for evaluating the increase at the point of loss due to incomplete combustion of the fuel is not limited to the above-described method.

In step S080, the controller 70 estimates the total loss moments of the internal combustion engine and advances the process to step S110. In this case, the controller 70 estimates (calculates) the total loss moment of the internal combustion engine as follows: "total loss moment of the internal combustion engine = cooling loss moment - exhaust loss moment + pumping loss moment + loss moment due to incomplete fuel combustion" (see FIG. . 5).

The controller 70 (CPU 71) may include a total loss torque estimating unit 71D of the internal combustion engine that performs the above-described processes of steps S025 and S060 to S080. The total loss torque estimation unit 71D of the internal combustion engine estimates the total loss torque of the internal combustion engine from the target output torque of the internal combustion engine. That is, estimates of the total amount of drive torque loss from the target drive torque to be generated by the internal combustion engine based on the required torque of the internal combustion engine. At this time, the controller 70 estimates the total loss torque of the internal combustion engine resulting from the boost reduction. The boost reduction can be effected by controlling the blower switching means. Boost reduction can occur during a transitional shift period. The boost reduction can occur immediately after the change in the number of blowers and can continue until the target boost state is reached (see FIG. 3). The blower switching means may be, for example, an intake bypass valve, an intake air changeover valve, an exhaust gas changeover valve, or the like.

In step S110, the controller 70 calculates a compensating motor torque based on the total loss torque of the internal combustion engine. The controller 70 then advances the process to step S115. For example, controller 70 may set the motor compensation torque value to be substantially the same as the total loss torque of the combustion engine (see "motor compensation torque" shown in FIG. 3).

The controller 70 (CPU 71) includes a motor compensation torque calculation unit 71E (see FIG. 1) for executing the process in step S110. The motor compensation torque calculating unit 71E calculates the motor compensation torque to be used by the motor generator to compensate for the total loss torque of the internal combustion engine.

In step S115, the controller 70 adds the compensation motor torque with the required motor torque (calculated in step S020) to determine the target motor output torque (see “target motor output torque” in FIG. 3). The controller 70 then advances the process to step S120.

The controller 70 (CPU 71) includes a torque compensation execution unit 71F for executing the process in step S115 (see FIG. 1). The torque compensation performing unit 71F adds the required motor torque and the motor compensation torque and determines the target output motor torque, which is the target driving torque to be generated by the motor generator.

In step S120, the controller 70 turns off the switching start flag and ends the process shown in FIG. eight.

Fuel injection process (Fig. 10) and motor-generator control process (Fig. 11)

FIG. 10 is an existing process schematically showing a fuel injection process. The controller 70 starts the process shown in FIG. 10 at a predetermined point in time and advances the process to step Q010.

In step SQ010, the controller 70 determines the amount of fuel in accordance with the target output torque of the internal combustion engine, stores the amount of fuel as the target amount of fuel, and advances to step SQ020.

In step SQ020, the controller 70 injects fuel of the target fuel volume from the injector at a predetermined time (fuel injection time) and ends the process.

FIG. 11 is an existing process schematically showing a process for controlling a motor generator. The controller 70 starts the process shown in FIG. 11 at a predetermined point in time and advances the process to step SM010.

In step SM010, the controller 70 controls the motor generator based on the target motor torque output and ends the process.

With the above processes, it is possible by the controller 70 to generate a driving torque with a reduced torque reduction from the total required torque, as shown by the section "driving torque actually generated by the internal combustion engine + driving torque actually generated by the motor generator" in FIG. ... 3.

An example of a vehicle equipped with an alternative hybrid system 1A (FIG. 12)

FIG. 12 shows an example of a vehicle equipped with a hybrid system 1A, an alternative to hybrid system 1 shown in FIG. 2. In the vehicle shown in FIG. 2, at least one of the internal combustion engine 10 and the motor generator 80 drives the rear wheels RR, RL. On the other hand, in the vehicle shown in FIG. 12, the internal combustion engine 10 drives the front wheels FR1, FL1 (front wheels), while the motor generator 80 drives the rear wheels RR, RL (rear wheels). More specifically, the vehicle shown in FIG. 12 is two-wheel drive when the driving torque is generated by any one of the internal combustion engine 10 or the motor generator 80. The vehicle is four-wheel drive (all-wheel drive) when the driving torque is generated by the internal combustion engine 10 and a motor generator 80. Hereinafter, the vehicle differences in FIGS. 12 from the vehicle shown in FIG. 2 will mainly be described.

The vehicle shown in FIG. 12, includes drive wheels FR1, FL1, RR, RL, differentials 17F, 17, transmission 16, clutch 15C, motor generator 80, internal combustion engine 10, controller 70, inverter 81, battery 82, etc. ... The controller 70 is adapted to detect the rotation speed of the internal combustion engine 10 based on the detected signal from the rotation detection means 25. The controller 70 is adapted to detect the rotation speed of the motor generator 80 based on the detected signal from the rotation detection means 80A. The controller 70 is further adapted to detect the rotation speed of the input shaft of the differential 17 based on the detected signals from the rotation detection means 17A.

The controller 70 detects the operating conditions of the internal combustion engine 10, the motor generator 80, the inverter 81, and the battery 82. The controller 70 controls the internal combustion engine 10, the motor generator 80, the inverter 81, the battery 82, and the clutch 15C in accordance with the operating conditions ...

For example, when only the front driving wheels FR1, FL1 are to be driven, the controller 70 controls the internal combustion engine 10 and generates a driving torque. At this time, the controller 70 controls the clutch 15C to be disengaged to control the inverter 81 so that the driving torque is not generated by the motor generator 80. In contrast, when only the rear driving wheels RR, RL must be driven in motion, the controller 70 controls the inverter 81 so that the driving torque is generated from the motor generator 80, and adjusts the clutch 15C to the engaged state. At this time, the controller 70 stops the internal combustion engine 10. When the front and rear driving wheels FR1, FL1, RR, RL are to be driven, the controller 70 controls the internal combustion engine 10 to generate a driving torque. In addition, the controller 70 controls the inverter 81 so that the driving torque is generated from the motor generator 80, and adjusts the clutch 15C to the engaged state.

The controller for a hybrid system according to the present invention should not be limited to the configuration, construction, processing procedures, operations, and the like described in the present embodiments, and various modifications, additions, and deletions can be performed without departing from the scope of the present invention. Additionally, the internal combustion engine system and the motor-generator system should not be limited to the systems described in the present embodiments, and may be applicable to various internal combustion engine systems and motor-generator systems.

The above-described internal combustion engine system includes two superchargers, namely, a first supercharger and a second supercharger. Alternatively, the internal combustion engine system can have three or more superchargers, and the above-described structures can be applied to reduce the torque drop during switching transients immediately after a change in the number of superchargers. The above-described embodiments include a first supercharger and a second supercharger for supercharging in parallel, and the first supercharger and the second supercharger may be supercharged in series. Alternatively, it is also possible to configure the provision of a plurality of superchargers to be supercharged in parallel, the plurality of superchargers being able to supercharge in series. Also with this configuration, by applying the system described above, it is possible to reduce the torque drop during the switching transition period immediately after the change in the number of superchargers. The above-described internal combustion engine includes a plurality of turbochargers as examples of the superchargers. Alternatively, the internal combustion engine system may include a plurality of mechanically driven superchargers. Alternatively, a combination of one or more turbochargers and superchargers can be used as superchargers. Also in this configuration, by applying the system described above, it is possible to reduce the torque drop during the switching transition period immediately after the change in the number of superchargers.

In the above-described embodiments, the motor generator is driven to compensate for the decrease in torque caused by the decrease in boost when the number of superchargers to be operated changes from one to two. Alternatively or in addition to this reduction in torque, the motor generator can be driven to compensate for the reduction in torque (loss moment) caused by various factors. The hybrid system may be constructed as shown, for example, the hybrid system in FIG. 2 or FIG. 12. Alternatively, the hybrid system can be of various designs to generate drive torque through an internal combustion engine and motor generator. The hybrid system, as described above, is installed in a vehicle. Alternatively, the hybrid system can be used for other purposes.

In the above-described embodiments, the total loss moment of the internal combustion engine is determined based on the cooling loss moment, the exhaust gas moment, the pumping loss moment, and the loss moment due to incomplete combustion of the fuel. As described above, the cooling loss moment is predominant (the proportion is large) in the total loss moment of the internal combustion engine. The moment of loss due to incomplete combustion of the fuel, the moment of the exhaust loss and the moment of the pumping loss are smaller than the moment of loss during cooling. Therefore, the total loss moment of the internal combustion engine may preferably include a cooling loss point, and more preferably includes at least one of a loss due to incomplete fuel combustion, an exhaust loss point, or a pumping loss point in addition to a loss point at cooling.

In addition, the numerical values used in the description of the present embodiments are merely examples and should not be limited to these numerical values. Additionally, equal to or greater than (≥), equal to or less than (≤), greater than (>), less than (<), etc., may or may not include an equal sign.

The various examples described in detail above with reference to the attached drawings are intended to be indicative of the present invention and are thus non-limiting embodiments. The detailed description is intended to teach one of ordinary skill in the art to create, use, and / or practice various aspects of the present teachings, and thus does not limit the scope of the invention in any way. In addition, each of the additional features and teachings described above can be applied and / or used alone or with other features and teachings in any combination to provide an improved controller for a hybrid system and / or ways to create and use it.

Claims (21)

1. A controller for controlling a hybrid system configured to generate driving torque by means of an internal combustion engine and a motor-generator, comprising: an operating condition detecting unit for detecting operating conditions of the internal combustion engine and the motor generator; a total required torque calculating unit for calculating the total required torque based on the operating conditions; a unit for dividing the total required torque for dividing the total required torque by the required torque of the internal combustion engine and the required torque of the motor; a total loss torque estimator of the internal combustion engine for evaluating the total loss torque of the internal combustion engine generated by the internal combustion engine based on the required torque of the internal combustion engine; a motor compensation torque calculating unit for calculating a motor compensation torque to be used by the motor generator to compensate for the total loss torque of the internal combustion engine; and a torque compensation performing unit configured to add the required motor torque and the compensating motor torque to determine the target motor output torque to be generated by the motor generator. 2. The controller of claim 1, wherein the internal combustion engine comprises: many blowers; and blower switching means configured to change the number of blowers to be used for boost control, the controller comprises a blower switching unit configured to: control blower switching means based on operating conditions and change the number of blowers to be used for boost control , wherein: the unit for estimating the total moment of losses of the internal combustion engine estimates the total moment of losses of the internal combustion engine resulting from the reduction of the boost in the transition period of switching, and the switching transition period is a period of time from immediately after switching the number of blowers by controlling the blower switching means until the target boost state is reached. 3. The controller of claim 2, wherein the total loss torque of the internal combustion engine as estimated by the controller includes a cooling loss torque that is lost due to the increased amount of heat loss of the pistons and cylinders of the internal combustion engine during the switching transition period. 4. The controller of claim 2 or 3, wherein the total loss moment of the internal combustion engine estimated by the controller further includes a loss moment due to incomplete combustion of fuel that must be lost due to an increased volume of fuel that does not fully react with air in cylinders during the transition period. 5. The controller of claim 2 or 3, wherein the total loss torque of the internal combustion engine estimated by the controller further includes an exhaust loss torque in accordance with a reduced amount of exhaust gas loss during the switching transition period. 6. The controller of claim 5, wherein the exhaust gas loss resulting from the boost reduction is based on the flow rate of the exhaust gas from the cylinders of the internal combustion engine. 7. The controller of claim 2 or 3, wherein the total loss torque of the internal combustion engine estimated by the controller further includes a pump loss torque that is lost due to the increased amount of pump loss in response to the pumping actions at inlet and outlet by the pistons in during the transitional switching period. 8. The controller according to any one of paragraphs. 1-3, while: the hybrid system is installed on the vehicle, the output torque generated by the internal combustion engine is transmitted to the front wheels of the vehicle, and the target motor output torque generated by the motor generator is transmitted to the rear wheels of the vehicle.

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