JP6624031B2 - Drive system controller - Google Patents

Description

  The present invention relates to a drive system for a hybrid vehicle, which can perform temperature increase of a catalyst device for purifying exhaust gas of an engine by predetermined catalyst temperature increase control of the engine and by energizing an electric heater. The present invention relates to a control device for controlling an electric heater.

  When an electric heater is provided in the catalyst device for purifying the exhaust of the engine, the temperature of the catalyst device can be increased by controlling the temperature of the catalyst using the engine as a heat source, while the temperature can be increased by energizing the electric heater. It is also possible. For example, in the hybrid vehicle disclosed in Patent Literature 1, one of the engine catalyst temperature increase control and the energization of the electric heater is selected based on the engine water temperature.

  In the vehicle disclosed in Patent Literature 2, in a drive system having an engine and a continuously variable transmission, when the speed ratio of the continuously variable transmission is increased to increase the engine speed and raise the temperature of the catalyst, the temperature of the catalyst increases. When the engine speed becomes higher than the allowable value for suppressing vibration, the gear ratio is limited to the allowable value, and the catalyst temperature is increased by the air-fuel ratio control.

JP 2012-224147 A JP-A-2000-230418

  However, in the vehicle of Patent Literature 1, when either the catalyst temperature increase control using the engine as a heat source or the electric heater is selected, the fuel efficiency of both is not studied. Further, in the vehicle of Patent Document 2, when either the temperature increase of the catalyst by the speed ratio control or the temperature increase of the catalyst by the air-fuel ratio control can be selected, the engine speed is limited to an allowable value or less. In realizing the required catalyst temperature raising performance, fuel efficiency by both types has not been studied. Further, in the vehicle of Patent Document 2, neither the possibility of using an electric heater for raising the temperature of the catalyst nor the effect of this on fuel economy is examined.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a drive system capable of increasing the temperature of a catalyst device for purifying exhaust gas of an engine by a predetermined catalyst temperature increase control of the engine and by energizing an electric heater. In order to achieve the required catalyst temperature raising performance while suppressing the discomfort or discomfort caused by the fuel consumption, by selecting one of the combination of the catalyst temperature raising control and the electric heater in consideration of the fuel efficiency, the fuel efficiency is improved. It is an object of the present invention to provide a device capable of improving the performance.

In order to solve the above-described problems, a drive system control device according to the present invention includes:
A continuously variable transmission that changes the rotational power transmitted from the internal combustion engine and outputs it to the drive wheels, a rotary electric machine that can generate electric power using the rotational power transmitted from the internal combustion engine, and a catalyst that purifies exhaust gas from the internal combustion engine An electric heater provided in the device, and mounted on a vehicle including the internal combustion engine, the continuously variable transmission, a driving system control device for controlling the rotating electric machine and the electric heater,
A first mode in which the temperature of the catalyst device is increased by at least a predetermined catalyst temperature increase control using the internal combustion engine as a heat source; and an output rotation speed and an output torque having a lower fuel consumption rate than the internal combustion engine in the first mode. A second mode in which the temperature of the catalyst device is raised by supplying electric power generated by the rotating electric machine to the electric heater while operating at the same time, in order to shift the catalyst device to a predetermined temperature rising state. The required output speed and output torque are calculated, the fuel consumption rate when operating at the calculated output speed and output torque is predicted, and the amount of change from the current value of the calculated output speed is determined by a predetermined value. If the guard value deviates from the guard area, the amount of change in the output rotation speed is limited to the guard value that defines the guard area, and the guard value is appropriately used as the change amount. In order to supply an insufficient amount of heat due to the operation at the output rotation speed, the calculated output torque is corrected to the increasing side, and the electric power generated by the rotating electric machine is increased by the increased output power accompanying the correction. Fuel supply prediction means configured to predict a fuel consumption rate as a supply to the heater;
According to the mode with the lower predicted fuel consumption rate of the first mode and the second mode, and when the variation is out of the guard area, the guard value is applied as the variation. Controlling the internal combustion engine by the output rotation speed and the corrected output torque, and, in order to supply the electric heater with electric power generated by the rotating electric machine by an output power increased by the correction, the internal combustion engine; Control means configured to control the continuously variable transmission, the rotating electric machine, and the electric heater.

  According to the configuration of the present invention, the control means selects and executes a mode having a low fuel consumption rate from the first mode and the second mode. Therefore, fuel efficiency can be improved by selecting one of the temperature increasing modes in consideration of fuel efficiency while achieving the required catalyst temperature increasing performance.

  Further, when the amount of change in the output rotation speed from the current value deviates from a predetermined guard region, the fuel efficiency prediction unit limits the amount of change in the output rotation speed to a guard value that defines the guard region, and In order to supply an insufficient amount of heat due to the operation at the output rotation speed to which the guard value was applied as the amount, the output torque was corrected to the increasing side and the rotating electric machine generated power by the increased output power accompanying the correction. Assuming that electric power is supplied to the electric heater, a fuel consumption rate is predicted. Therefore, a sense of discomfort or discomfort caused by a rapid change in the output rotation speed can be suppressed, and the result of the correction can be reflected in the prediction of the fuel consumption rate, the selection of the heating mode, and the specification of the operation.

FIG. 1 is a conceptual diagram illustrating an overall configuration of a drive system control device according to an embodiment of the present invention. FIG. 3 is a skeleton diagram showing details of a drive system. 9 is an engagement operation table showing engagement or disengagement of a friction engagement element used for a shift speed switching process at each shift speed. FIG. 4 is a collinear diagram illustrating a rotation operation of each rotation element of a planetary gear included in a drive system. A shift diagram illustrating a shift switching control based on a vehicle speed and a required torque, a shift switching diagram showing a boundary line for switching between a stepped shift and a stepless shift in the shift switch control, and an engine running and a motor running. It is a map which shows an example of each with a power source switching diagram showing a boundary line to be switched. FIG. 3 is a block diagram illustrating a configuration of a control system. 8 is an engine speed-engine torque map showing a procedure for setting an operating point of an engine when a catalyst temperature increase request is issued. It is a flowchart which shows the procedure of a mode selection process. 9 is an engine rotation speed-engine torque map showing a procedure for setting an operating point of an engine when a catalyst temperature rise request is made and a rotation speed change amount is larger than a predetermined value. 5 is a graph showing an exhaust loss and a net fuel consumption rate in the case of a first mode. 9 is a graph showing an exhaust loss and a net fuel consumption rate in the case of a second mode.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a conceptual diagram showing a configuration of a hybrid vehicle according to an embodiment of the present invention. The hybrid vehicle 1 includes a drive system including an engine 10 that is an internal combustion engine, and rotating electric machines MG1 and MG2 that are connected to the engine 10 via a power distribution mechanism 14, respectively. The power distribution mechanism 14, the rotary electric machines MG1, MG2, and the stepped transmission unit 15 constitute a power transmission mechanism 110. The rotating electric machines MG1 and MG2 are composed of, for example, a permanent magnet type three-phase synchronous motor generator. The first rotating electrical machine MG <b> 1 is mainly used for controlling the engine 10 and generating electric power by rotating power transmitted from the engine 10. On the other hand, the second rotating electric machine MG2 is mainly used for powering and regenerative braking of the hybrid vehicle 1.

  An intake passage 11 and an exhaust passage 12 are connected to the engine 10. In the intake passage 11, an air flow meter 21, a throttle valve 22, a compressor 23c of a turbocharger 23, and an intercooler 24 are provided. In the exhaust passage 12, a turbine 23t of the turbocharger 23, a start converter 25, and a post-processing device 26 are provided. The exhaust passage 12 is further provided with a bypass passage communicating with the upstream of the turbine 23t and between the turbine 23t and the start converter 25, and a waste gate valve 27 is provided in the bypass passage.

  The start converter 25 purifies exhaust gas at the time of starting the engine in which the aftertreatment device 26 is not activated, and is composed of, for example, a three-way catalyst. The post-processing device 26 includes, for example, one of a storage reduction type NOx catalyst (NSR: NOx Storage Reduction) and a selective reduction type NOx catalyst (SCR: Selective Catalytic Reduction).

  The post-processing device 26, which is a catalyst device in the present invention, is provided with an electric heater 28 configured to be able to heat the catalyst by supplying electric power. As a heat source of the electric heater 28, a heat source that generates Joule heat (for example, a heating wire), a heat source that performs dielectric heating or induction heating by the action of an electromagnetic wave (for example, a magnetron), or the like can be used. The heater power supply 29 connected to the electric heater 28 includes a relay and the like inside, and is configured to supply electric power from a battery (not shown) to the electric heater 28. When the relay inside the heater power supply 29 is closed, the electric heater 28 is energized, and the temperature of the catalyst in the post-processing device 26 rises. When the relay inside the heater power supply 29 is opened, the energization of the electric heater 28 is stopped. In this way, by controlling the heater power supply 29, the amount of power supply to the electric heater 28 (hereinafter, appropriately referred to as "heater power supply amount") is controlled.

  As shown in FIG. 2, the power transmission mechanism 110 includes an input shaft 111 to which the rotational power output from the engine 10 is input, and a left and right drive wheel 109 connected to a differential gear (differential gear device) 150. An output shaft 112 that outputs rotational power transmitted to the motor, a transmission shaft 113 that is interposed between the input shaft 111 and the output shaft 112 and transmits the rotational power so as to relay the rotational power, and between the input shaft 111 and the transmission shaft 113. And a power distribution mechanism 14 that distributes the rotational power of the engine 10 to the rotary electric machines MG1 and MG2 and outputs the power, and a rotational power transmitted from the power distribution mechanism 14 that is disposed between the output shaft 112 and the transmission shaft 113. And a stepped transmission unit 15 that outputs the power by automatically shifting at a speed with power.

  In this power transmission mechanism 110, an input shaft 111, an output shaft 112, and a transmission shaft 113 are housed in series in a transmission case 119 such that the shaft centers are a common axis, and each of the power transmission mechanisms 110 is rotatably provided via a bearing or the like. Supported. Here, the rotation speed (rotation speed) of the output shaft 112 is detected by the vehicle speed sensor 51, the rotation speed of the rotor of the first rotating electric machine MG1 is detected by the first MG rotation speed sensor 53, and the rotation speed of the rotor of the second rotating electric machine MG2 is determined. The rotation speed of the integral transmission shaft 113 is installed so that the second MG rotation speed sensor 54 detects the rotation speed. The vehicle speed sensor 51, the first MG rotation speed sensor 53, and the second MG rotation speed sensor 54 are connected to be able to transmit a sensor signal to the HVECU 31 described later. In addition, FIG. 2 is a skeleton diagram (skeleton diagram) in which the lower side in the figure is omitted because the power transmission mechanism 110 is configured to be rotationally symmetric about the axis of the input shaft 111 and the like.

  In the power distribution mechanism 14, the first rotary electric machine MG1 and the second rotary electric machine MG2 are connected to a single pinion type planetary gear mechanism 121 having a switching clutch C0 and a switching brake B0, and distribute and output the rotational power of the engine 10. It has become. The planetary gear mechanism 121 includes a sun gear S0, a planetary gear P0, a carrier CA0, and a ring gear R0 as rotating elements. The first rotary electric machine MG1 is connected to the sun gear S0 of the planetary gear mechanism 121 so that the rotor rotates integrally. The second rotary electric machine MG2 is connected to the ring gear R0 of the planetary gear mechanism 121 and the transmission shaft 113 so that the rotor rotates integrally therewith. The carrier CA0 of the planetary gear mechanism 121 is connected to the input shaft 111, that is, the output shaft of the engine 10. The switching brake B0 is installed in the transmission case 119, and engages or releases the sun gear S0. The switching clutch C0 engages or releases the connection between the sun gear S0 and the carrier CA0. The switching clutch C0 and the switching brake B0 are driven by hydraulic pressure to adjust an engagement pressure with a target member to be brought into pressure contact, thereby maintaining an engaged state, a released state, and a frictional contact (so-called sliding) state. It is constructed by a combination element.

  For example, when the switching clutch C0 and the switching brake B0 are released, the power distribution mechanism 14 is placed in a differential state in which the sun gear S0, the carrier CA0, and the ring gear R0 can relatively rotate. At this time, the output (rotary power) of the engine 10 is distributed to the first rotary electric machine MG1 and the second rotary electric machine MG2 (the transmission shaft 113), and, for example, the first rotary electric machine MG1 generates electric power with the distributed output of the engine 10. And the second rotating electric machine MG2 is driven as an electric motor. As a result, the power distribution mechanism 14 is in a so-called continuously variable transmission state (electrical CVT: Continuously Variable Transmission) by the rotary electric machines MG1 and MG2, and the rotational speed of the transmission shaft 113 is independent of the predetermined rotational speed of the engine 10. Can be changed to a differential state in which the speed of the input shaft 111 / the speed of the transmission shaft 113 is continuously changed to output to the driving wheel side. It can function as a machine. When functioning as electric motors, rotating electric machines MG1 and MG2 receive supply (discharge) of electric power stored in battery 108 via inverter 107 to rotate and rotate, and function as generators. The generated power is charged (stored) in the battery 108 via the inverter 107.

  When one of the switching clutch C0 and the switching brake B0 is engaged, the power distribution mechanism 14 is set to a non-differential state in which differential rotation is impossible. For example, when the sun gear S0 and the carrier CA0 are engaged by the switching clutch C0, the power distribution mechanism 14 is brought into a locked state in which the power distribution mechanism 14 and the ring gear R0 are integrally rotated, and is brought into a non-differential state in which differential rotation is impossible. . At this time, the speed ratio of the engine 10 and the speed of the transmission shaft 113 are fixed to a gear ratio “1”. As a result, the power distribution mechanism 14 is brought into the constant speed change state in the non-stepless speed change state, so that the stepped speed change unit 15 is in a state where the stepped speed change is possible.

  Further, even if sun gear S0 is connected to transmission case 119 by switching brake B0 and locked, power distribution mechanism 14 is in a non-differential state in which differential rotation is impossible. At this time, the ring gear R0 is rotated at a higher speed than the carrier CA0. As a result, the power distribution mechanism 14 enters a constant speed-up (shift) state in a non-stepless speed-change state, and a state in which the step-variable transmission unit 15 can perform a step-wise speed change.

  The stepped transmission unit 15 includes switching clutches C1, C2 and switching brakes B1, B2, B3 together with a first planetary gear mechanism 125, a second planetary gear mechanism 126, and a third planetary gear mechanism 127, all of which are of a single pinion type. In addition, it functions as a four-speed stepped automatic transmission. The first planetary gear mechanism 125 includes a sun gear S1, a planetary gear P1, a carrier CA1, and a ring gear R1 as rotating elements. The second planetary gear mechanism 126 includes a sun gear S2, a planetary gear P2, a carrier CA2, and a ring gear R2 as rotating elements. The third planetary gear mechanism 127 includes a sun gear S3, a planetary gear P3, a carrier CA3, and a ring gear R3 as rotating elements. The switching clutches C1, C2 and the switching brakes B1, B2, B3 are constructed by the same frictional engagement elements as the switching clutch C0 and the switching brake B0.

  In this stepped transmission portion 15, the sun gear S1 and the sun gear S2 are connected so as to rotate integrally, and are connected to the transmission shaft 113 via the switching clutch C2 so as to be fastened or released. Further, the ring gear R2 and the sun gear S3 are connected so as to rotate integrally, and are connected to the transmission shaft 113 via the switching clutch C1 so as to be fastened or released. Further, the ring gear R1, the carrier CA2, and the carrier CA3 are connected to the output shaft 112 so as to rotate integrally. The switching brakes B1, B2, and B3 are installed in the transmission case 119. The switching brake B1 engages or releases the sun gear S1 and the sun gear S2 that rotate together, and the switching brake B2 engages or releases the carrier CA1. The brake B3 engages or releases the ring gear R3.

  In the power transmission mechanism 110 configured as described above, one of the switching clutch C0 and the switching brake B0 of the power distribution mechanism 14 is driven to be engaged by the drive control of the HVECU 31 described below, and the stepped transmission portion 15 The switching clutches C1, C2 and the switching brakes B1, B2, B3 are selectively driven to be engaged. As a result, the rotational power of the engine 10 and the rotary electric machines MG1 and MG2 transmitted from the power distribution mechanism 14 via the transmission shaft 113 is switched to a later-described gear position in accordance with various driving conditions such as the vehicle speed, thereby changing the speed. The output is output from the output shaft 112 to the drive wheel 109 side. That is, the power transmission mechanism 110 constitutes a stepped transmission.

  In addition, the power transmission mechanism 110 is brought into the continuously variable transmission state by the switching control of the power distribution mechanism 14 being released by the drive control of the HVECU 31 to be described later. As a result, a state in which it can function as an electric continuously variable transmission is established.

  In the power transmission mechanism 110, a transmission path is formed so that rotational power can be output by setting one of the switching clutches C1 and C2 of the stepped transmission portion 15 to an engaged state. As a result, the transmission path of the rotational power is cut off.

  Specifically, as shown in the engagement operation table of FIG. 3, the power transmission mechanism 110 includes the switching clutch C0 and the switching brake B0 of the power distribution mechanism 14, and the switching clutches C1, C2 and the switching brake of the stepped transmission unit 15. By selectively engaging B1, B2, and B3, a continuously variable speed, or a first speed (1st), a second speed (2nd), a third speed (3rd), a fourth speed (4th), a fifth speed ( 5th), R (Reverse), or N (Neutral), a stepped speed change step is selected to form a transmission path. In FIG. 3, “を” indicates that the vehicle is in the engaged state during the selective driving, and “◎” indicates that the vehicle is in the engaged state during the selective driving during the above-described stepped shifting, but is selected during the stepless shifting. This indicates that the motor is released when driven. Further, in the hybrid vehicle 1 according to the present embodiment, for example, by selecting a shift lever (not shown), parking “P (parking)”, reverse running “R (reverse)”, and neutral “N ( Neutral), forward travel "D (drive)", and forward travel "M (manual)" are selectable. When the "D" position is selected, the continuously variable transmission control is executed. When the "M" position is selected, the stepped shift control is executed.

  The power distributing mechanism 14 and the stepped transmission portion 15 of the power transmission mechanism 110 have respective rotating elements (sun gear S) by appropriately engaging the switching clutches C0, C1, C2 and the switching brakes B0, B1, B2, B3. , The carrier CA and the ring gear R) rotate while maintaining the relationship of the rotational speed shown in the alignment chart of FIG. In the alignment chart of FIG. 4, the rotating elements (the sun gear S, the carrier CA, and the ring gear R) that are connected and integrally rotate are combined into one vertical line so that a predetermined rotation speed ratio (speed ratio) is obtained. Are set so that the intersection between the straight line crossing the vertical line and the vertical line is the rotation speed of each rotary element.

  As shown in FIG. 6, the hybrid vehicle 1 further includes, as control devices, an engine ECU (Electronic Control Unit) 32 that controls the engine 10, an MGECU 33 that controls the rotating electric machines MG1 and MG2, respectively. An HVECU 31 that controls the engine ECU 32 and the MGECU 33 based on the output of various sensors provided in the hybrid vehicle 1 and the like is mounted. The HVECU 31, the engine ECU 32, and the MGECU 33 are electrically connected so that information can be exchanged with each other. The HVECU 31, the engine ECU 32, and the MGECU 33 constitute control means in the present invention. A single control device in which the functions of the HVECU 31, the engine ECU 32, and the MGECU 33 are integrated may be used.

  Signals from various sensors are input to the HVECU 31 provided as a main computer. For example, the HVECU 31 includes a vehicle speed sensor 51 that outputs a signal corresponding to the vehicle speed of the hybrid vehicle 1, an accelerator opening sensor 52 that outputs a signal corresponding to the amount of depression of an accelerator pedal (not shown), and a rotation speed of the first rotary electric machine MG1. The first MG rotation speed sensor 53 outputs a signal corresponding to the rotation speed of the second rotating electrical machine MG2, the second MG rotation speed sensor 54 outputs a signal corresponding to the rotation speed of the second rotating electrical machine MG2, and the state of charge (SOC) of the battery 108. Output signals from an SOC sensor 56 that outputs a detected signal and a catalyst temperature sensor 57 that is provided in the post-processing device 26 and that outputs a catalyst bed temperature are input.

  The HVECU 31 calculates a torque generated by the first rotating electrical machine MG1 and the second rotating electrical machine MG2, and outputs a command to the MGECU 33 regarding the generated torque. The HVECU 31 determines the operating conditions of the engine 10 and outputs a command to the engine ECU 32 regarding the operating conditions of the engine 10. Further, the HVECU 31 individually controls a plurality of clutches and a plurality of brakes in the stepped transmission unit 15 so that a gear position according to a predetermined shift schedule or a driver's shift change request or the like can be realized. The MGECU 33 calculates a current corresponding to the torque generated in the first rotating electrical machine MG1 and the second rotating electrical machine MG2 based on the command input from the HVECU 31, and outputs the current to the first rotating electrical machine MG1 and the second rotating electrical machine MG2. I do. The engine ECU 32 performs various controls on each part of the engine 10 such as the throttle valve 22, the ignition plug 37, and the waste gate valve 27 based on the command input from the HVECU 31, and controls the operation of the heater power supply 29 described above. Control.

  The HVECU 31 calculates the required driving force (power) required by the driver for the hybrid vehicle 1 with reference to the output signal of the accelerator opening sensor 52 and the output signal of the vehicle speed sensor 51, and calculates the required driving force. The hybrid vehicle 1 is controlled while switching various driving modes so that the system efficiency is optimized. For example, in a low load region where the thermal efficiency of the engine 10 decreases, the EV running mode in which the combustion of the engine 10 is stopped and the second rotating electrical machine MG2 is driven is selected. On the other hand, if the EV traveling mode is not in the operating range to be selected, the hybrid traveling mode in which the second rotating electrical machine MG2 and the like are operated together with the engine 10 is selected.

  The HVECU 31 uses, for example, a torque and a vehicle speed required to be output from the output shaft 112 as parameters as shown in a shift diagram of FIG. The shift control process is executed by outputting a drive control signal for setting the switching clutches C0, C1, C2 and the switching brakes B0, B1, B2, B3 to the engaged state or the released state. Here, FIG. 5 shows an example of a shift diagram showing shift lines SHd and SHu used when executing shift switching control using the vehicle speed and the output (requested) torque as parameters. FIG. 5 also shows an example of a shift switching diagram showing shift boundaries GCc and GCt between a stepped shift region and a stepless shift control region for switching between a stepped shift and a stepless shift. Further, FIG. 5 shows an engine traveling area and a motor traveling area in order to switch between the engine traveling in which the rotational power of the engine 10 is the traveling torque and the motor traveling in which the rotational power of the rotary electric machines MG1 and MG2 is the traveling torque. An example of the power source switching diagram showing the power boundary line PT of FIG.

  More specifically, the HVECU 31 executes the speed change control process at the timing of crossing the shift lines SHd and SHu in FIG. At this time, the HVECU 31 executes a shift stage switching control process for upshifting from the second speed to the third speed, for example, at the timing of crossing the upshift shift line SHu from the low speed side to the high speed side during acceleration. Further, the HVECU 31 executes a shift stage switching control process for downshifting from the fourth speed to the third speed, for example, at the timing of crossing the downshift shift line SHd from the high speed side to the low speed side during deceleration.

  The HVECU 31 executes a control process for switching between the stepped shift and the stepless shift at the timing of crossing the shift boundary lines GCc and GCt in FIG. At this time, when the HVECU 31 crosses the continuously variable shift boundary GCc from the high torque side to the low torque side, the shift clutch C0 of the power distribution mechanism 14 and the switch brake A shift type switching control process is executed in which B0 is released and the process shifts to the continuously variable shift control region. The HVECU 31 switches the switching clutch C0 or the switching brake B0 of the power distribution mechanism 14 at the timing of crossing the stepped shift boundary GCt from the low torque side to the high torque side while keeping the speed of the stepped transmission portion 15 as it is. Is set to the engaged state, and a shift type switching control process for shifting to the stepped shift control region is executed.

  Now, when the hybrid driving mode is selected, the continuously variable transmission mode is basically performed, and the engine 10 and the engine 10 are moved so that the operating point of the engine moves substantially along the optimal fuel consumption line L shown in FIG. The first rotating electric machine MG1 and the like are controlled. The operating point of the engine 10 is defined by the engine speed and the engine torque, and the optimal fuel consumption line L is set so that the thermal efficiency of the engine 10 is optimized, that is, various engine powers are minimized per engine 10 alone. Are set in advance by plotting and connecting the points realized with the fuel consumption of.

  However, when there is a request for raising the temperature of the catalyst of the post-processing device 26, such as at the time of a cold start, the post-processing device 26 is shifted to a predetermined temperature rising state, that is, a predetermined activation temperature within a predetermined time. In order to perform the operation, the operation in the temperature raising mode is performed. The HVECU 31 according to the present embodiment is provided with two different modes as the temperature increasing mode, that is, a first mode and a second mode.

  In the first mode, the temperature of the post-processing device 26 is raised by controlling the temperature of the catalyst of the engine 10. Specifically, such a catalyst temperature increase control of the engine 10 is performed when the target power, which is the target value of the output power of the engine 10, is normally set (that is, when the engine 10 is operating and the temperature increase request is not satisfied). Is to change the target rotation speed, which is the target value of the output rotation speed of the engine 10, to an increasing side while maintaining the value of the rotation speed. The setting of the operating point in the first mode is performed, for example, as shown in FIG. 7, by setting the operating point from the current operating point S as much as necessary to supply the amount of heat required to raise the temperature of the post-processing device 26. This is performed by moving the engine on the power line P to the side where the engine speed increases (point A0, arrow m1). As the engine speed increases, the exhaust loss [kW], that is, the heat flow discharged from the engine 10 into the exhaust passage increases, whereby the temperature of the post-processing device 26 increases.

  In the second mode, the electric power generated by the first rotating electrical machine MG1 is supplied to the electric heater 28 while the engine 10 is operated at an engine speed and an engine torque having a lower fuel consumption rate than the first mode, thereby providing a later-described mode. The temperature of the processing device 26 is raised. In the second mode in the present embodiment, the operating point of the engine 10 is moved on the optimal fuel consumption line L to the power increasing side. In the setting of the operating point in the second mode, for example, as shown in FIG. 7, the operating point is optimized from the current operating point S by an amount necessary to supply a heat amount necessary for raising the temperature of the post-processing device 26. This is performed by moving the engine power on the fuel consumption line L to the side where the engine power increases (point B0, arrow m2). As the engine speed increases, the exhaust loss [kW], that is, the heat flow discharged from the engine 10 into the exhaust passage increases, and the first rotary electric machine MG1 increases due to an increase in engine power due to execution of the second mode. Is subjected to a power generation operation (regeneration operation), and the electric power is supplied to the electric heater 28, whereby the temperature of the post-processing device 26 is increased.

  Further, the HVECU 31 has a mode selection process for selecting one of the first mode and the second mode based on the prediction of the fuel consumption rate.

  This mode selection process will be described with reference to FIG. The processing routine of FIG. 8 is repeatedly executed at a predetermined control cycle Δt when the continuously variable transmission mode is selected and the catalyst temperature increase request is satisfied. The catalyst temperature rise request is satisfied, for example, when the detection value of the catalyst temperature sensor 57 is equal to or less than a predetermined value. When this routine is started, first, the HVECU 31 is required for the catalyst bed temperature in the after-treatment device 26 to reach a predetermined activation temperature within a predetermined time based on the detection value of the catalyst temperature sensor 57. The required amount of heat Qr, which is the amount of heat, is calculated (S10).

  Next, in step S20, the HVECU 31 calculates an operating point A0 (see FIG. 7) when the required amount of heat Qr is supplied in the first mode, and calculates the engine speed from the current operating point S in this case. A certain rotation speed change amount ΔNeA is calculated. That is, the HVECU 31 supplies the necessary heat amount Qr calculated in step S10 to the post-processing device 26 when changing the operating point of the engine 10 on the equal power line P (that is, when operating in the first mode). The rotation speed change amount ΔNeA required to shift to the activation temperature is calculated.

  Next, in step S30, it is determined whether the calculated rotation speed change amount ΔNeA is smaller than a predetermined upper limit value ΔNe1. The upper limit value ΔNe1 is a threshold value such that when the change amount of the engine speed within a predetermined time (for example, within the control cycle Δt) is larger than that, the discomfort felt by the occupant is outside the allowable range. That is, in step S30, when the operating point is changed according to the rotation speed change amount ΔNeA calculated in step S20 (that is, the operating point is changed from the current operating point S to the operating point A0), the discomfort is within the allowable range. Is determined. The upper limit ΔNe1 corresponds to a guard value that defines a guard area in the present invention.

  If the determination in step S30 is negative, that is, if the rotation speed change amount ΔNeA is equal to or greater than the upper limit value ΔNe1, then the rotation speed change amount ΔNeA is updated with the upper limit value ΔNe1 (step S40), and the operating point is reset by this updated value. It is calculated (step S50).

  The procedure for recalculating the operating point will be described with reference to FIG. 9. If the rotational speed change amount ΔNeA for the operating point A0 calculated in step S20 is equal to or greater than the upper limit value ΔNe1, first (i) The change amount ΔNeA is updated with the upper limit value ΔNe1. (Ii) In this case (that is, in the case of the operation point A1), the shortage heat amount (difference with the required heat amount Qr) in the supply heat amount in the first mode is calculated by the operation point The operating point A ′ is newly calculated so as to be ensured by changing to the torque increasing side.

  In the case of affirmative determination in step S30 and in the case where recalculation is performed in step S50, the operating point (the operating point A0 in the case of affirmative in step S30 and the operation point in the case where recalculation is performed in step S50). The net fuel consumption rate FCa [g / kWh] for the point A ′) is calculated (step S60).

  In steps S70 to S90, the same processing as that performed in the first mode in steps S20 to S60 is executed for the second mode.

  That is, first, in step S70, the operating point B0 (see FIG. 7) when the required amount of heat Qr is supplied in the second mode is calculated, and the change amount ΔNeB of the engine speed in that case is calculated. That is, the amount of change ΔNeB in engine speed required to supply the required heat amount Qr calculated in step S10 to the post-processing device 26 to shift to the activation temperature is changed by changing the operating point of the engine on the optimal fuel consumption line. The calculation is performed for the case (that is, the case of operating in the second mode).

  Next, in step S80, it is determined whether or not the calculated rotation speed change amount ΔNeB is smaller than the above-described predetermined upper limit value ΔNe1. That is, in step S80, when the operating point is changed according to the rotation speed change amount ΔNeB calculated in step S70 (that is, the operating point is changed from the current operating point S to the operating point B0), the discomfort falls within the allowable range. Is determined.

  If the determination in step S80 is negative, that is, if the rotation speed variation ΔNeB is equal to or greater than the upper limit ΔNe1, the rotation speed variation ΔNeB is updated with the upper limit ΔNe1 (step S100), and the operating point is reset by this updated value. It is calculated (step S110).

  The procedure for recalculating the operating point will be described with reference to FIG. 9. If the rotational speed change amount ΔNeB for the operating point B0 calculated in step S70 is equal to or more than the upper limit value ΔNe1, first (i) The change amount ΔNeB is updated with the upper limit value ΔNe1. (Ii) In this case (ie, according to the operation point B1), the shortage heat amount (difference with the required heat amount Qr) in the supply heat amount in the second mode is calculated as the operation point The operating point B ′ is newly calculated so as to be ensured by changing to the torque increasing side.

  In the case of affirmative determination in step S80 and in the case where recalculation is performed in step S110, the operating point (the operating point B0 in the case of affirmative determination in step S80 and the operation point in the case where recalculation is performed in step S110). The net fuel consumption rate FCb [g / kWh] for the point B ′) is calculated (step S90). Note that the processing in steps S60 and S90 corresponds to the fuel efficiency prediction means in the present invention.

  In calculating each operating point, an increase in exhaust loss (heat flow supplied to the post-processing device 26 using the engine 10 as a heat source) by correcting the engine torque to an increase side and an increase in the engine by the correction are provided. Both the increase in the amount of heat supplied by supplying the electric power generated by the first rotating electrical machine MG1 to the electric heater 28 by the torque is considered or reflected. The amount of heat lost in the exhaust passage from the engine 10 to the aftertreatment device 26 is calculated by subtracting it. In addition, since the power generation efficiency differs according to the rotation speed of the first rotating electrical machine MG1 (for example, the power generation efficiency is low at low rotation speed), the power generation efficiency according to the rotation speed is also considered or reflected.

  In step S120, the HVECU 31 determines whether the net fuel consumption rate FCa for the first mode previously calculated in step S60 is smaller than the net fuel consumption rate FCb for the second mode calculated in step S90. I do.

  If the determination in step S120 is affirmative, that is, if the net fuel consumption rate FCa for the first mode is relatively small (that is, the fuel efficiency is good), the operation in the first mode is executed (step S130). As the operating point in this case, the operating point A0 is adopted when the result is affirmative in step S30, and the operating point A 'is adopted when recalculation is performed in step S50.

  If step S120 is negative, that is, if the net fuel consumption rate FCb for the second mode is equal to or less than the net fuel consumption rate FCa (ie, the fuel efficiency is equal or good), the operation in the second mode is executed (step S120). S140). As the operating point in this case, the operating point B0 is adopted when the result is affirmative in step S80, and the operating point B 'is adopted when recalculation is performed in step S110. In this way, in steps S130 and S140, if the amount of change in the engine speed is equal to or greater than the upper limit value ΔNe1 according to the adopted operating point, the engine speed in which the upper limit value ΔNe1 is applied as the change amount The engine 10 and the power distribution device 14 are controlled so that the engine 10 is controlled by the corrected engine torque and the electric power generated by the first rotating electrical machine MG1 is supplied to the electric heater 28 by the increased engine power accompanying the correction. , The first rotating electrical machine MG1 and the heater power supply 29 are controlled.

  For example, as shown in FIG. 10, when the engine speed is increased from the current value Rs to the target value R0 in the first mode, the increase in the exhaust loss is ΔEL1 [kW], while the net fuel consumption rate is increased. The increase of FCa is ΔFCa [g / kWh]. On the other hand, as shown in FIG. 11, when the engine power (output shaft power [kW]) is increased from the current value Ps to the target value P0 in the second mode, the increase in the exhaust loss is ΔEL2 [kW]. On the other hand, the increase in the net fuel consumption rate FCb is ΔFCb [g / kWh]. In this case, in step S120, the result is negative because FCa> FCb, and the operating point (B), that is, the operation in the second mode is selected.

  In the determination in step S120, the operating point A ′ is used when recalculation is performed in step S50, and the operating point B ′ is used when recalculation is performed in step S110. Will be done. When the operating point A ′ or B ′ is adopted, the electric power generated by the first rotary electric machine MG1 is supplied to the electric heater 28 by the increased engine power resulting from the correction of the engine torque to the increased side. .

  When the operating points A0 and B0 are both within the range of the upper limit value ΔNe1 of the rotation speed change amount from the current operating point S, the operating point B0 set in the second mode is on the optimal fuel consumption line L. Therefore, it is generally considered that the second mode is adopted and executed. On the other hand, when one or both of the operating points A0 and B0 are outside the range of the upper limit ΔNe1 from the current operating point S (for example, when the catalyst temperature is extremely low such as in a cold region), the first mode is set. Whether the second mode or the second mode is adopted or executed depends on the net fuel consumption rates FCa and FCb. In the first mode, when the operating point A0 is within the range of the upper limit ΔNe1, the electric heater 28 is used. When the operation point A0 is not within the range of the upper limit value ΔNe1, the energization of the electric heater 28 is executed even in the first mode. That is, in the present embodiment, even when the first mode is adopted and executed, the energization of the electric heater 28 is performed, and therefore, the mere two states (the catalyst rise of the engine 10 always on the equal power line P) occur. Rather than selecting between a first mode in which only the temperature control is performed and the electric heater 28 is not energized, and a second mode in which the electric heater 28 is always operated on the optimal fuel consumption line L and energized in the electric heater 28). From all the points on the torque map that are divided in a grid pattern, the operating point that can secure the required temperature raising performance and has the smallest fuel consumption rate can be arbitrarily adopted.

  As described above, in the present embodiment, the engine 10, the power distribution mechanism 14 functioning as a continuously variable transmission, the first rotating electric machine MG1, and the electric motor are operated in accordance with the lower fuel consumption rate of the first mode and the second mode. The heater 28 is controlled. Therefore, fuel efficiency can be improved by selecting one of the temperature increasing modes in consideration of fuel efficiency while achieving the required catalyst temperature increasing performance.

  Further, in the present embodiment, when the change amounts ΔNeA and ΔNeB of the engine speed from the current value are equal to or larger than the predetermined upper limit value ΔNe1, the change amounts ΔNeA and ΔNeB of the engine speed are limited to the upper limit value ΔNe1. In order to supply an insufficient amount of heat due to the operation at the engine speed to which the upper limit value ΔNe1 is applied as the change amount of the engine speed, the engine torque is corrected to the increasing side, and the engine power is increased by the increased engine power accompanying the correction. The fuel consumption rate is predicted on the assumption that the electric power generated by the single-rotation electric machine MG1 is supplied to the electric heater 28. In addition, the engine 10 is controlled by the engine speed to which the upper limit value ΔNe1 is applied as the change amount of the engine speed and the engine torque after the correction, and the first rotary electric machine MG1 is controlled by the increased engine power accompanying the correction. The generated power is supplied to the electric heater 28. Therefore, discomfort or discomfort caused by a rapid change in the engine speed can be suppressed, and the correction results are used to predict the fuel consumption rate, select the temperature increase mode, and specify the operation (that is, the position of the operation point). Can be reflected.

  While embodiments of the present invention have been disclosed, it will be apparent that modifications may be made by those skilled in the art without departing from the scope of the invention. All such modifications and equivalents are intended to be included within the scope of the appended claims.

  For example, when selecting the temperature increase mode, the state of charge (SOC) of a power storage device such as the battery 108 may be considered. For example, even when the amounts of change ΔNeA and ΔNeB of the engine speed from the current value are equal to or larger than the predetermined upper limit value ΔNe1, if the SOC is sufficiently high, the amount of increase in the engine torque is suppressed and For example, as the SOC is higher (closer to full charge), the rate of power supply from the power storage device may be increased, such as supplying the electric power from the power storage device to the electric heater 28. In this case, the fuel consumption rate can be further reduced. Further, when power is supplied from the power storage device to the electric heater 28 as described above, the lower the temperature of the power storage device, the lower the rate of power supply from the power storage device may be. In general, the internal resistance of the power storage device tends to increase as the temperature decreases, and thus the fuel consumption rate can be further reduced according to such a configuration.

  Further, in the calculation of the fuel consumption rate (S60, S90) in the present invention, it is more preferable that the power transmission efficiency of the continuously variable transmission portion is also taken into consideration. That is, by calculating or correcting the fuel consumption rate using the value of the known power transmission efficiency according to the gear ratio, the calculation accuracy of the fuel consumption rate is improved, and the selection of the temperature increase mode with a lower fuel consumption rate is performed. The fuel consumption rate can be further reduced.

  Further, the control of the engine in at least one of the first mode and the second mode may change the target rotation speed to a decrease side. For example, when the operating point is changed to the rotational speed decreasing side (torque increasing side) on the equal power line in the first mode, the operating point deviates from the optimal fuel consumption line L, so that the combustion efficiency is reduced. By supplying the corresponding energy to the catalyst, the temperature of the catalyst can be raised. When the target rotation speed is changed to the decrease side in the second mode, the target torque also decreases, so that the catalyst temperature rise due to the control of the engine itself cannot be expected, but as in the case where the SOC of the power storage device is sufficiently high. By supplying the insufficient power from the power storage device to the electric heater 28, a desired catalyst temperature increase can be performed. In the second mode, it is generally difficult to imagine the necessity of reducing the target rotation speed to a predetermined lower limit or less, but the present invention does not exclude such a configuration. As described above, in at least one of the first mode and the second mode in the present invention, the target rotation speed of the engine 10 is changed to the decrease side, and the amount of change in the engine rotation speed from the current operating point S in that case. If the rotation speed change ΔNeA is less than or equal to a predetermined lower limit that is a negative value, the rotation speed change ΔNeA is updated with the lower limit, and the operating point is recalculated based on the updated value. Is also good. That is, the fuel efficiency prediction means in the present invention calculates and calculates the output rotation speed and the output torque required to shift the catalyst device to the predetermined temperature rising state in each of the first mode and the second mode. The fuel consumption rate when operating at the output rotational speed and the output torque is predicted, and the amount of change from the current value of the calculated output rotational speed is defined by at least one of a positive guard value and a negative guard value. If the output value deviates from the predetermined guard region, the amount of change in the output rotational speed is limited to a guard value that defines the guard region, and operation at the output rotational speed to which the guard value is applied as the change amount is performed. In order to supply the shortage of heat due to the above, the calculated output torque is corrected to the increasing side, and the electric power generated by the rotating electric machine by the increased output power due to the correction. As to supply to the electric heater may be configured to predict the fuel consumption rate. In other words, the guard area used in the present invention is only a positive guard value in both the first mode and the second mode (in this case, the heating mode is caused by an increase in the output rotation speed. And, when the output rotation speed is equal to or more than the positive guard value, the positive guard value is applied), only the negative guard value (in this case, the heating mode is caused by the decrease in the output rotation speed). And the output rotation speed is equal to or less than the negative guard value, the negative guard value is applied), and the positive and negative guard values (in this case, the heating mode is the output rotation speed The positive guard value is applied when the output rotation speed is equal to or more than the positive guard value, and the negative guard value is applied when the output rotation speed is equal to or less than the negative guard value. Is applied) It may have.

  Further, as a catalyst temperature raising control of the engine 10, other methods, such as a method of retarding the ignition timing of the engine 10 than usual, a method of making the air-fuel ratio richer than usual, and a plurality of such methods A combination of methods can be employed. In the above-described embodiment, an example in which the present invention is applied to a hybrid vehicle having a rotating electric machine usable as a driving source has been described. However, the present invention relates to a rotating electric machine exclusively used for power generation (for example, a three-phase AC synchronous motor of a slip ring excitation type). The present invention can also be applied to a vehicle having an alternator including a generator. As the continuously variable transmission of the present invention, a mechanically continuously variable transmission (for example, a belt-type CVT, a chain-type CVT, or a toroidal-type CVT) may be employed instead of the above-described electric continuously variable transmission. .

DESCRIPTION OF SYMBOLS 1 Hybrid vehicle 10 Engine 14 Power distribution mechanism 15 Stepped transmission portion 31 HVECU
32 Engine ECU
33 MGECU
108 Battery MG1, MG2 rotating electric machine

Claims (1)

A continuously variable transmission that changes the rotational power transmitted from the internal combustion engine and outputs it to the drive wheels, a rotary electric machine that can generate electric power using the rotational power transmitted from the internal combustion engine, and a catalyst that purifies exhaust gas from the internal combustion engine An electric heater provided in the device, and mounted on a vehicle including the internal combustion engine, the continuously variable transmission, a driving system control device for controlling the rotating electric machine and the electric heater,
A first mode in which the temperature of the catalyst device is increased by at least a predetermined catalyst temperature increase control using the internal combustion engine as a heat source; and an output rotation speed and an output torque having a lower fuel consumption rate than the internal combustion engine in the first mode. A second mode in which the temperature of the catalyst device is raised by supplying electric power generated by the rotating electric machine to the electric heater while operating at the same time, in order to shift the catalyst device to a predetermined temperature rising state. The required output speed and output torque are calculated, the fuel consumption rate when operating at the calculated output speed and output torque is predicted, and the amount of change from the current value of the calculated output speed is determined by a predetermined value. If the guard value deviates from the guard area, the amount of change in the output rotation speed is limited to the guard value that defines the guard area, and the guard value is appropriately used as the change amount. In order to supply an insufficient amount of heat due to the operation at the output rotation speed, the calculated output torque is corrected to the increasing side, and the electric power generated by the rotating electric machine is increased by the increased output power accompanying the correction. Fuel supply prediction means configured to predict a fuel consumption rate as a supply to the heater;
According to the mode with the lower predicted fuel consumption rate of the first mode and the second mode, and when the variation is out of the guard area, the guard value is applied as the variation. Controlling the internal combustion engine by the output rotational speed and the corrected output torque, and, in order to supply the electric heater with electric power generated by the rotating electric machine by an output power increased by the correction, the internal combustion engine; A control system for a drive system, comprising: a control unit configured to control the continuously variable transmission, the rotating electric machine, and the electric heater.

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