JP2017214893A - Engine mounted with exhaust-driven generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve purification performance of a purification device while securing power generating capacity.SOLUTION: An engine mounted with an exhaust-driven generator comprises: a power generation turbine 74 installed in an exhaust passage 130; a turbine side generator 72 which is driven by the power generation turbine and generates power; and an engine side generator 82 which is connected to an output shaft 106 of an engine body 1. The engine mounted with the exhaust-driven generator: causes the turbine side generator 72 to generate power when a temperature of a purification device 90 is not less than a first reference temperature during deceleration; stops power generation with the turbine side generator 72 when the temperature is lower than a second reference temperature; and causes the engine side generator 82 to generate power when the temperature of the purification device 90 is lower than the second reference temperature and power generation request is received.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an engine equipped with an exhaust drive generator.

  Conventionally, in an engine system, a generator is provided in order to generate electric power to be supplied to various electric devices.

  For example, Patent Document 1 discloses an engine system that includes a turbocharger and a generator that generates power using exhaust energy, and the generator is connected to a shaft that connects a turbocharger turbine and a compressor. In other words, a device that generates electric power by the rotational force of a shaft is disclosed. In this engine system, the energy of the exhaust is effectively used for supercharging and power generation, so that the energy efficiency of the entire system can be improved.

JP 2007-262970 A

  However, in the engine system of Patent Document 1, as a result of exhaust energy being consumed by power generation, the temperature of the exhaust gas flowing into the purification device provided downstream of the exhaust passage is lowered, and the purification performance of the purification device is maintained well. There is a risk that it will not be possible. In particular, when the engine is decelerated, the temperature of the purification device is likely to decrease as the temperature of the exhaust gas is low. Therefore, if power is generated during deceleration of the engine in the engine system of Patent Document 1, the purification performance of the purification device deteriorates. There is a fear.

  This invention is made | formed in view of the above situations, and provides the engine provided with the exhaust drive generator which can make the purification performance of a purification apparatus more favorable, ensuring the amount of electric power generation. Objective.

  In order to solve the above-mentioned problems, the present invention is an engine including an exhaust drive generator, and is provided in an engine body, an intake passage and an exhaust passage connected to the engine body, and the exhaust passage. A power generation device including a power generation turbine that rotates in response to exhaust energy and a turbine-side generator that is driven by the power generation turbine to generate power, and is connected to the output shaft of the engine body and is rotationally driven by the output shaft. An engine-side generator for generating electricity, a purification device for purifying exhaust gas provided downstream of the power generation turbine in the exhaust passage, an engine including the turbine-side generator and the engine-side generator Control means capable of controlling each part, and the control means is preset with a temperature of the purification device when the engine body is decelerated. When the temperature is equal to or higher than one reference temperature, at least the turbine-side generator is configured to generate power. When the temperature of the purification device is lower than the second reference temperature set lower than the first reference temperature at the time of deceleration, Exhaust gas that stops power generation by a turbine-side generator and causes the engine-side generator to generate power when the temperature of the purification device is lower than the second reference temperature and there is a power generation request at the time of deceleration. An engine including a drive generator is provided.

  According to this structure, the energy at the time of deceleration can be collect | recovered as electric power by generating with an engine side generator or a turbine side generator using the energy at the time of deceleration.

  In addition, if the temperature of the purification device is lower than the second reference temperature during engine deceleration, power generation by the turbine-side generator is stopped and power generation is performed by the engine-side generator even when there is a power generation request. It is possible to improve the purification performance of the purification device by suppressing an excessive decrease in the temperature of the device.

  Further, in this configuration, when the temperature of the purification device is as high as the first reference temperature or higher during deceleration, at least power generation by the turbine-side generator is performed. Therefore, it is possible to suppress an excessive increase in the temperature of the purification device by reducing the temperature of the exhaust gas in the turbine-side generator while effectively using the energy of the exhaust gas for power generation. Therefore, it is possible to improve the purification performance of the purification device more reliably while securing the power generation amount.

  In the above configuration, a turbocharger including a turbocharger provided upstream of the power generation turbine in the exhaust passage and a compressor provided in the intake passage, and the supercharger provided in the exhaust passage. A bypass passage that communicates a portion between the turbine and the power generation turbine and a portion upstream of the supercharging turbine; and an on-off valve that opens and closes the bypass passage; and the control means includes the engine It is preferable to open the on-off valve during deceleration of the main body (Claim 2).

  According to this configuration, since the supercharging and power generation are performed by the exhaust energy, the exhaust energy can be used effectively.

  In addition, according to this configuration, the on-off valve is opened when the engine body is decelerated, and at least a portion of the exhaust bypasses the supercharging turbine and is led to the downstream side. Therefore, it is possible to suppress cooling of the supercharging turbine by introducing relatively low temperature exhaust discharged from the engine body during deceleration. Accordingly, the temperature of the turbocharging turbine can be increased even after deceleration, and the driving force of the turbocharging turbine, that is, the turbocharging performance of the turbocharger can be increased during acceleration after deceleration.

  In the above configuration, when the engine body is decelerating, the temperature of the purification device is equal to or higher than the second reference temperature and lower than the first reference temperature, and there is a request for power generation. In this case, it is preferable that power generation is performed only by the engine-side generator when the power generation request is low, and that power generation by the turbine-side power generator is performed in addition to the engine-side generator when the power generation request is high. 3).

  According to this configuration, appropriate power generation according to the power generation request can be performed by the engine-side generator and the turbo-side generator while maintaining the temperature of the purification device appropriately.

  As described above, according to the engine provided with the exhaust drive generator of the present invention, the purification performance of the purification device can be improved while securing the amount of power generation.

It is a schematic block diagram of an engine system. It is a schematic sectional drawing of an engine main body. It is a schematic sectional drawing of VGT. It is the figure which showed the control block. It is the flowchart which showed the procedure of control concerning electric power generation etc.

(1) Overall Configuration FIG. 1 is a schematic configuration diagram of an engine system 100 to which an engine including an exhaust drive generator according to an embodiment of the present invention is applied.

  The engine system 100 includes an engine body 1, an intake passage 120 through which intake air introduced into the engine body 1 flows, an exhaust passage 130 through which exhaust gas (combustion gas) derived from the engine body 1 flows, and an exhaust passage 130. The turbocharger 60 is driven by the exhaust gas flowing through the exhaust passage 130, and the power generator 70 is driven by the exhaust gas flowing through the exhaust passage 130 to generate electric power. Here, as shown in FIG. 1 and the like, a case will be described in which the engine body 1 is a four-stroke in-line four-cylinder gasoline engine and is mounted on a vehicle as a drive source.

  FIG. 2 is a schematic sectional view of the engine body 1.

  The engine body 1 includes a cylinder block 101 in which a cylinder 10 is formed, a cylinder head 102 provided on the upper surface of the cylinder block 101, and a piston 103 that is inserted into the cylinder 10 so as to be slidable back and forth. Yes.

  The piston 103 is connected to a crankshaft (an output shaft of the engine main body 1) 106 via a connecting rod, and the crankshaft 106 rotates around its central axis in accordance with the reciprocating motion of the piston 103.

  As shown in FIG. 1, an engine-side generator 82 that is driven by the rotational force of the crankshaft 106 to generate electric power is connected to the crankshaft 106. In the present embodiment, the engine-side generator 82 is a generator with a motor function, so-called ISG (Integrated Starter Generator), which is driven by the crankshaft 106 as described above to function as a generator, and at the time of starting or acceleration. It functions as a motor at times and assists the rotation of the crankshaft 106. Below, the engine side generator 82 is called ISG82. The ISG 82 is controlled by the ISG driving device 85, and the ISG driving device 85 switches between the generator and the motor, and the amount of power generation and the driving force as the motor are changed.

  A combustion chamber 5 is formed above the piston 103. An injector 105 is attached to the side wall of the cylinder block 101 so as to face the combustion chamber 5. Fuel is injected from the injector 105 into the combustion chamber 5. The injected fuel / air mixture burns in the combustion chamber 5, and the piston 103 is pushed down by the expansion force generated by the combustion, and reciprocates up and down. The injector 105 may be attached to the cylinder head 102.

  The cylinder head 102 is provided with a spark plug 18 that performs ignition by spark discharge on the mixture of fuel and air injected from the injector 105.

  In the cylinder head 102, corresponding to each cylinder 10, an intake port 13 for introducing air supplied from the intake passage 120 into the combustion chamber 5 of each cylinder 10 and an intake valve 14 for opening and closing the intake port 13. And an exhaust port 11 for leading exhaust generated in the combustion chamber 5 of each cylinder 10 to the outside of the engine body 1 and an exhaust valve 12 for opening and closing the exhaust port 11.

  The intake passage 120 is provided so as to be connected to each intake port 13. In the intake passage 120, a compressor 62, an intercooler 122, a throttle valve 123, and a surge tank 124 are provided in this order from the upstream side.

  The compressor 62 is a component part of the turbocharger 60. That is, the turbocharger 60 includes a turbocharger 64 that is provided in the exhaust passage 130 and is rotationally driven by exhaust gas, and a compressor 62 that is provided in the intake passage 120 and is rotationally driven by the turbocharger turbine 64. The supercharging turbine 64 (specifically, an impeller 64a to be described later of the supercharging turbine 64) rotates upon receiving the introduction of exhaust gas, whereby the compressor 62 rotates to supercharge intake air.

(2) Exhaust System The exhaust passage 130 is provided so as to be connected to each exhaust port 11 of the engine body 1. In the exhaust passage 130, a supercharging turbine 64, a power generation turbine 74, and a catalyst device (purification device) 90 are provided in this order from the upstream side.

  As shown in FIG. 3, in the present embodiment, the supercharging turbine 64 is a variable capacity turbine, that is, a VGT (Variable Geometry Turbine), and is provided around an impeller 64a that rotates by receiving the energy of the exhaust, and the impeller 64a. A plurality of nozzle vanes 64b whose angles can be changed, a rod 64c associated with each nozzle vane 64b, and a vane actuator 64d that changes the angle of each nozzle vane 64b by driving the rod 64c forward and backward. When the nozzle vane 64b is driven by the vane actuator 64d and the rod 64c in the closing direction (the direction in which the distance between the adjacent nozzle vanes 64b is reduced), the area of the flow path of the exhaust gas flowing into the impeller 64a of the supercharging turbine 64 is reduced. The exhaust flow rate is increased.

  Hereinafter, the angle of the nozzle vane 64b is referred to as a VGT opening. The larger the value of the VGT opening, the larger the flow passage area of the exhaust passage toward the blades of the supercharging turbine 64 and the lower the flow velocity of the exhaust gas that collides with the blades, the smaller the value. This is a parameter indicating that the flow area of the exhaust gas is reduced by reducing the flow path area.

  In the present embodiment, during the operation of the engine, the VGT opening is controlled to be equal to or more than a predetermined opening on the opening side with respect to the fully closed state (a state in which the flow passage is completely closed).

  Returning to FIG. 1, the power generation turbine 74 is a component of the power generation device 70. The power generation device 70 includes the power generation turbine 74, a turbine side generator 72 that is rotationally driven by the power generation turbine 74, and a generator drive device 75 that drives the turbine side power generator 72.

  The power generation turbine 74 is a turbine that rotates by receiving the energy of the exhaust gas, and the turbine generator 72 is driven to rotate by the power generation turbine 74 to generate power. Specifically, the turbine-side generator 72 has a rotor coil that rotates in conjunction with the power generation turbine 74, and generates power by electromagnetic induction accompanying the rotation of the rotor coil. The electric power generated by the turbine-side generator 72 is stored in a battery (not shown) or supplied to various electric devices (not shown).

  The generator drive device 75 switches between execution / stop of power generation by the turbine-side generator 72, that is, execution / stop of application of a current for magnetization to the rotor coil of the turbine-side generator 72, and the power generation amount of the turbine-side generator 72. To change.

  The catalyst device 90 is a device for purifying exhaust gas, and includes, for example, an oxidation catalyst.

  The exhaust passage 130 is provided with a bypass passage 132 that bypasses the supercharging turbine 64 and a wastegate valve (open / close valve) 133 that opens and closes the bypass passage 132. Specifically, the bypass passage 132 connects a portion of the exhaust passage 130 that is upstream of the supercharging turbine 64 and a portion of the exhaust passage 130 that is downstream of the power generation turbine 74. Therefore, when the wastegate valve 133 is open, most of the exhaust discharged from the engine body 1 flows into the catalyst device 90 without passing through the supercharging turbine 64.

(3) Control system The control system of an engine system is demonstrated using FIG. The engine system 100 of the present embodiment is controlled by an ECU (engine control unit, control means) 500 mounted on the vehicle. As is well known, ECU 500 is a microprocessor including a CPU, ROM, RAM, I / F, and the like.

  ECU 500 receives information from various sensors. For example, the ECU 500 is provided in the vehicle, an engine speed sensor SN1 for detecting the rotation speed of the crankshaft 106, that is, the rotation speed of the engine body 1, an air flow sensor SN2 for detecting the amount of intake air flowing into the engine body 1. An accelerator opening sensor SN3 for detecting the opening of an accelerator pedal (not shown) that is operated by the driver, a pressure downstream of the compressor 62 in the intake passage 120, that is, a supercharging pressure of the compressor 62 (hereinafter, simply referred to as “compressor pressure”). A supercharging pressure sensor SN4 for detecting the supercharging pressure), an exhaust temperature sensor SN5 for detecting the exhaust temperature which is the temperature of the exhaust passage 130, etc., and input signals from these sensors. Accept. In addition, the battery voltage and operation signals of various electric devices are also input to the ECU 500.

  The ECU 500 executes various calculations based on input signals from the sensors SN1 to SN5 and the like, and generates a generator driving device 75, an ISG driving device 85, a waste gate valve 133, and other parts of the engine (the spark plug 18, Control signals are output to the injector 105, the throttle valve 123, etc., respectively. Specifically, ECU 500 outputs a control signal to an actuator that opens and closes waste gate valve 133 to control the opening degree thereof.

  A control procedure of the generator driving device 75, the ISG driving device 85, and the waste gate valve 133 by the ECU 500 will be described with reference to the flowchart of FIG.

  First, in step S1, the controller 500 detects the engine speed detected by the engine speed sensor SN1, the accelerator opening detected by the accelerator opening sensor SN5, the supercharging pressure detected by the supercharging pressure sensor SN5, The catalyst temperature, which is the temperature of the catalyst device 90, and the SOC, which is the remaining battery level, are read. The catalyst temperature is calculated separately from the exhaust temperature detected by the exhaust temperature sensor SN4. Further, the SOC is separately calculated from the detection value of the current sensor connected to the battery.

  Next, in step S3, the target boost pressure, which is the target value of the boost pressure, and the basic VGT opening, which is the basic value of the VGT opening, are set according to the operating conditions (engine speed, engine load, etc.). Set. For example, the controller 500 stores in advance a map of the target boost pressure and the basic VGT opening degree for the engine speed and engine load, and the controller 500 corresponds to the current engine speed and engine load. Each value is extracted from each map. The engine load is calculated from the engine speed and the accelerator opening.

  Next, in step S4, it is determined whether or not the engine body 1 is decelerating (during deceleration). For example, the controller 500 determines whether or not the vehicle is decelerating based on the amount of fuel supplied to the cylinder 10 and the amount of change between the engine speed and the engine load.

  In the present embodiment, in addition to the so-called fuel cut in which the supply of fuel to the cylinder 10 is stopped, it is determined that the engine is decelerating even when the engine speed and the engine load are decreasing.

  If the determination in step S4 is YES and the engine body 1 is decelerating, the process proceeds to step S5.

  In step S5, the waste gate valve 133 is opened.

  As described above, in this embodiment, when the engine body 1 is decelerated, the waste gate valve 133 is opened to bypass the supercharging turbine 72 so that much of the exhaust gas discharged from the engine body 1 (almost all) is bypassed. Then flow downstream. After step S5, the process proceeds to step S6.

  In step S6, it is determined whether there is a power generation request.

  Specifically, the controller 500 calculates the amount of power that is currently insufficient with respect to a predetermined amount of power based on the SOC, the electrical load of various electrical devices, and the like, and if the amount of power shortage is greater than or equal to a predetermined value. It is determined that there is a power generation request. The predetermined amount of power is, for example, the maximum amount of power stored in the battery, and is calculated by subtracting the current amount of power stored in the battery and the amount of power consumed by various electric devices from the maximum amount of stored power.

  If the determination in step S6 is NO and there is no power generation request, the process proceeds to step S7, and power generation by the ISG 82 is stopped.

  On the other hand, if the determination in step S6 is YES and there is a power generation request, the process proceeds to step S8 and power generation by the ISG 82 is performed.

  Thus, in this embodiment, if there is a power generation request during deceleration of the engine body 1, power generation by the ISG 82 is performed.

  After step S7 or step S8, the process proceeds to step S9.

  In step S9, it is determined whether or not the catalyst temperature is equal to or higher than a preset allowable temperature (first reference temperature). The allowable temperature is a sufficiently high temperature and is set to a minimum temperature in a temperature range that is not preferable for the catalyst device 90.

  When the determination in step S9 is YES and the catalyst temperature is higher than the allowable temperature, the process proceeds to step S10. In step S <b> 10, power generation by the turbine generator 72 is performed. Specifically, a magnetizing current is applied to the rotor coil of the turbine generator 72 by the generator driving device 75. After step S10, the process proceeds to step S16.

  On the other hand, if the determination in step S9 is NO and the catalyst temperature is less than the allowable temperature, the process proceeds to step S11.

  In step S11, it is determined whether or not the catalyst temperature is lower than a preset activation temperature.

  Here, the activation temperature is set to the lowest temperature when the catalyst device 90 is activated.

  When the determination in step S11 is YES and the catalyst temperature is lower than the activation temperature and the catalyst device 90 is not in the activated state, the process proceeds to step S12.

  In step S12, power generation by the turbine-side generator 72 is stopped. Specifically, the generator driving device 75 stops the application of magnetization current to the rotor coil of the turbine generator 72. After step S12, the process proceeds to step S16.

  On the other hand, if the determination in step S11 is NO and the catalyst temperature is equal to or higher than the activation temperature, that is, if the catalyst device 90 is in the active state, the process proceeds to step S13.

  In step S13, it is determined whether or not the power generation request is high, that is, whether or not there is a power generation request and the power should be generated urgently. Specifically, when the power shortage amount is larger than the reference shortage amount set to a value higher than the predetermined value and the power is largely insufficient (relative to the predetermined power amount), the power generation request is made. It is determined that the power is high, that is, the power should be generated urgently. For example, this determination is YES when the SOC has dropped below a predetermined value and there is a possibility that power shortage will soon occur (a state in which necessary electrical equipment cannot be operated normally) unless power generation is performed.

  If the determination in step S13 is YES and the power generation request level is high and it is necessary to generate power urgently, the process proceeds to step S14, and power generation by the turbine generator 72 is performed in step S14. After step S14, the process proceeds to step S16.

  On the other hand, if the determination in step S13 is NO and the power generation request level is low or there is no power generation request, the process proceeds to step S15, and power generation by the turbine-side generator 72 is stopped in step S15. After step S15, the process proceeds to step S16.

  In step S16, it is determined whether or not the supercharging pressure is the target supercharging pressure. If this determination is NO and the target boost pressure is not realized, the process proceeds to step S17.

  In step S17, the VGT opening is corrected. Specifically, when the supercharging pressure is lower than the target supercharging pressure, the VGT opening is decreased (corrected to the closing side), and when the supercharging pressure is higher than the target supercharging pressure, the VGT opening Is increased (corrected to the open side). For example, when the VGT opening is the basic VGT opening, the VGT opening is increased or decreased from the basic VGT opening.

  On the other hand, when the determination in step S16 is YES and the supercharging pressure is controlled to the target supercharging pressure, the processing is terminated as it is.

  In step S16, the supercharging pressure is not limited to the case where the supercharging pressure completely coincides with the target supercharging pressure, but the supercharging pressure is also increased when the difference between the supercharging pressure and the target supercharging pressure is a predetermined value or less. It may be determined that the target boost pressure is reached.

  Thus, in the present embodiment, when the engine body 1 is decelerated, when the catalyst temperature is higher than the allowable temperature, or when the catalyst temperature is higher than the activation temperature and the power generation requirement is high, power generation by the turbine-side generator 72 is performed. Is implemented. On the other hand, when the catalyst temperature is lower than the activation temperature or when the power generation requirement is low when the engine body 1 is decelerated, the power generation by the turbine-side generator 72 is stopped.

  If the determination in step S4 is NO and the vehicle is not decelerating, the process proceeds to step S20.

  In step S20, the waste gate valve (W / G) 133 is fully closed. After step S20, the process proceeds to step S21.

  In step S21, while power generation by the ISG 82 is stopped, when there is a power generation request, power generation by the turbine-side generator 72 is performed accordingly. After step S21, the process proceeds to step S22. In step S22, the VGT opening is controlled to the basic VGT opening, and the process ends.

(4) Operation, etc. As described above, in the engine system 100, the ISG (engine-side generator) 82 that generates power by the rotation of the crankshaft 106 and the exhaust passage 130 are used to generate power. The turbine-side generator 72 that performs the power generation is provided, and the engine-side generator 82 and further the turbine-side generator 72 can generate power by using the energy at the time of deceleration. Therefore, energy at the time of deceleration can be recovered as electric power, and a high power generation amount can be obtained efficiently.

  Moreover, when the catalyst temperature is lower than the activation temperature during deceleration, power generation by the ISG 82 is performed in response to a power generation request, while power generation by the turbine-side generator 72 is stopped. Therefore, activation of the catalyst device 90 can be promoted while securing the amount of power generation.

  Specifically, the temperature of the exhaust discharged from the engine body 1 during deceleration is relatively low. Therefore, if the power generation by the turbine generator 72 is further performed at this time and the exhaust energy is consumed by the power generation turbine 74, the temperature of the exhaust gas flowing into the catalyst device 90 becomes very low. On the other hand, in the engine system 100, the activation of the catalyst device 90 is promoted by stopping the power generation by the turbine-side generator when the catalyst temperature is lower than the activation temperature during deceleration as described above. can do.

  Further, in the engine system 100, when the catalyst temperature is high, which is higher than the allowable temperature during deceleration, power generation by the turbine-side generator 72 is performed regardless of whether there is a power generation request. Therefore, it is possible to reduce the temperature of the exhaust in the power generation turbine 74 while effectively using the energy of the exhaust for power generation, thereby suppressing the temperature of the catalyst device 90 from becoming excessively high. Therefore, it is possible to improve the purification performance of the catalyst device more reliably while securing the power generation amount. In addition, when there is no power generation request and it is not necessary to add power to the battery and the electric device, power is supplied to, for example, an electric fan.

  Further, in the engine system 100, when the power generation request is high at the time of deceleration when the catalyst temperature is equal to or higher than the activation temperature and lower than the allowable temperature, power generation is also performed by the turbine side generator 72 in addition to the ISG 82. Is done. Therefore, it is possible to obtain a high power generation amount according to the demand while maintaining the purification performance of the catalyst device 90 satisfactorily.

  Further, in the engine system 100, at the time of deceleration, the waste gate valve 133 is opened, and the exhaust discharged from the engine body 1 flows down bypassing the supercharging turbine 64. Therefore, it is possible to suppress the supercharging turbine 64 from being cooled by the relatively low temperature exhaust discharged from the engine body 1 during deceleration. Therefore, the supercharging performance of the turbocharger 60 can be maintained high by suppressing the driving force of the supercharging turbine 64 from being reduced as the supercharging turbine 64 is cooled. In particular, the supercharging pressure can be increased more reliably during acceleration after deceleration, and acceleration performance can be improved.

(5) Modified Example In the above embodiment, the case where the supercharging turbine 64 is provided on the upstream side of the power generation turbine 74 in the exhaust passage 130 has been described, but the supercharging turbine 64 may be omitted. However, if the turbocharging turbine 64 is provided, the exhaust energy can be used for supercharging in addition to power generation, and the supercharging performance can be improved and the energy efficiency of the entire system can be increased.

  Further, in the above-described embodiment, the case where the supercharging turbine 64 is a variable capacity turbine has been described. It may be a fixed turbine.

  Further, the waste gate valve 133 can be omitted. However, if the waste gate valve 133 is provided and opened at the time of deceleration, as described above, the temperature drop of the supercharging turbine 64 can be suppressed and the supercharging performance can be improved more reliably.

  In the above embodiment, the case where power generation by the turbine-side generator 64 is performed only when the power generation request is high when the catalyst temperature is equal to or higher than the activation temperature and lower than the allowable temperature at the time of deceleration is described. Even when the demand for power generation is low when the catalyst temperature is equal to or higher than the activation temperature and lower than the allowable temperature at the time of deceleration, the turbine-side generator 72 may be driven as the power generation request is issued. .

  However, if the power generation by the turbine-side generator 72 is performed only when the power generation requirement is high as in the above-described embodiment and the power generation by the ISG 82 is preferentially performed at the time of deceleration, the turbine-side generator 72 It is possible to more reliably suppress the catalyst temperature from being reduced with power generation, and to increase the resistance force of the engine body 1 and increase the deceleration force.

  Moreover, you may use the other apparatus which can store electric power instead of a battery. In addition, the determination of the level of the power generation request level is not limited to the above, and may be determined based on, for example, the amount of power consumed by the electrical device.

  Further, the turbine-side generator 72 is not limited to the above as long as it is driven by the power generation turbine 74 and can switch between the execution and the stop of the power generation. For example, the power generation by the generator may be stopped by releasing the connection between the generator and the power generation turbine.

  Moreover, although the said embodiment demonstrated the case where the engine main body 1 was a 4-cylinder gasoline engine, the kind of engine main body 1 is not restricted to this. For example, a diesel engine or an engine having another number of cylinders may be used.

DESCRIPTION OF SYMBOLS 1 Engine main body 60 Turbocharger 62 Compressor 64 Turbocharging turbine 70 Power generator 72 Turbine side generator 74 Power generation turbine 82 ISG (engine side generator)
90 Catalyst device (Purification device)
100 engine system (turbocharged engine)
106 Crankshaft (output shaft)
120 Intake passage 130 Exhaust passage 132 Bypass passage 133 Wastegate valve (open / close valve)
500 ECU (control means)

Claims (3)

An engine with an exhaust drive generator,
The engine body,
An intake passage and an exhaust passage respectively connected to the engine body;
A power generation apparatus including a power generation turbine that is provided in the exhaust passage and rotates by receiving energy of exhaust gas, and a turbine generator that is driven by the power generation turbine to generate electric power;
An engine-side generator that is connected to the output shaft of the engine body and is driven to rotate by the output shaft;
A purification device for purifying exhaust gas provided at the downstream side of the power generation turbine in the exhaust passage;
Control means capable of controlling each part of the engine including the turbine-side generator and the engine-side generator,
The control means includes
When the temperature of the purification device is equal to or higher than a preset first reference temperature during deceleration of the engine body, at least the turbine-side generator is configured to generate power,
When the temperature of the purifier is lower than the second reference temperature set to a temperature lower than the first reference temperature at the time of deceleration, the power generation by the turbine-side generator is stopped,
An engine equipped with an exhaust drive generator, wherein the engine-side generator is configured to generate power when the temperature of the purification device is lower than the second reference temperature and there is a power generation request during deceleration. In the engine provided with the exhaust drive generator according to claim 1,
A turbocharger including a turbocharger provided upstream of the power generation turbine in the exhaust passage and a compressor provided in the intake passage;
A bypass passage provided in the exhaust passage and communicating a portion between the supercharging turbine and the power generating turbine and a portion upstream of the supercharging turbine;
An on-off valve for opening and closing the bypass passage,
An engine equipped with an exhaust drive generator, wherein the control means opens the on-off valve when the engine body is decelerated. In the engine provided with the exhaust drive generator according to claim 1 or 2,
The control means generates a power generation request when the engine body is decelerating, the temperature of the purification device is equal to or higher than the second reference temperature and lower than the first reference temperature, and there is a power generation request. An exhaust-driven generator characterized in that power generation is performed only by the engine-side generator when power is low, and power generation by the turbine-side power generator is performed in addition to the engine-side power generator when power generation demand is high. Engine equipped.

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