JP2006207457A - Control device of rotary electric equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To crank an engine by driving a starter by proper torque corresponding to the oil temperature, while restraining a cost increase and impairment of a degree of freedom of a layout of an apparatus. <P>SOLUTION: An engine ECU executes a program including a step (S108) of estimating the oil temperature (the temperature of engine oil), a step (S110) of estimating friction of the engine from the estimated oil temperature, a step (S112) of determining driving voltage of the starter in low voltage as the friction becomes low, that is, the oil temperature becomes high, a step (S114) of cranking the engine by driving the starter by the determined driving voltage, and a step (S120) of starting the engine by igniting air-fuel mixture in a cylinder by a spark plug when an engine speed NE becomes a threshold value NE(O) or more (YES in S118) when the engine speed NE increases by cranking. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a control device for a rotating electrical machine in a vehicle equipped with a heat storage system that temporarily stores a liquid medium in a warm state, and particularly to a vehicle that supplies a high-temperature liquid medium to an internal combustion engine to control the temperature of the internal combustion engine. The present invention relates to a control device for a rotating electrical machine.

  When an internal combustion engine mounted in an automobile or the like is started in a cold state, the wall surface temperature of the intake port, the combustion chamber, etc. becomes low, so that it is difficult for the fuel to atomize and flame extinguishing occurs at the periphery of the combustion chamber This will cause a decrease in startability and a deterioration in exhaust emission.

  To solve this problem, a water-cooled internal combustion engine is equipped with a heat storage device that retains high-temperature cooling water, and the internal combustion engine is supplied with cooling water stored in the heat storage device when the internal combustion engine is started. Techniques have been proposed for increasing the engine temperature, thereby improving startability and speeding up warm-up.

  For example, an internal combustion engine provided with a heat storage device disclosed in Japanese Patent Application Laid-Open No. 2003-184553 (Patent Document 1) is formed in a cylinder head of the internal combustion engine, and a heat medium flow passage through which a heat medium flows, and a heat medium flow A heat storage device that retains and stores a part of the heat medium flowing through the passage, a first heat medium passage that guides the heat medium from the heat storage device to the heat medium flow passage, and a second that guides the heat medium from the heat medium flow passage to the heat storage device And a passage switching means for selectively conducting the first heat medium passage and the second heat medium passage.

  According to the internal combustion engine provided with this heat storage device, the passage switching means causes the first heat medium passage to conduct, so that the high-temperature heat medium stored in the heat storage device through the first heat medium passage passes through the first heat medium passage. While being directly supplied to the heat medium flow passage, the passage switching means causes the second heat medium passage to conduct, so that the high-temperature heat medium in the heat medium flow passage directly passes through the second heat medium passage. Is supplied to the heat storage device. When the heat medium is directly exchanged between the heat medium flow passage and the heat storage device in this way, heat loss when supplying the heat medium from the heat storage device to the heat medium flow passage is minimized. In addition, heat loss when supplying the heat medium from the heat medium flow path to the heat storage device is also suppressed to a minimum. As a result, even if the heat medium in the heat medium flow passage has a small amount of heat, the small amount of heat is efficiently stored in the heat storage device.

  In order to improve fuel efficiency and exhaust emission performance, vehicles equipped with an idling stop system that stops an internal combustion engine (engine) when the vehicle is stopped have been put into practical use. In a vehicle equipped with this idling stop system, the engine is frequently stopped and started repeatedly. The engine is generally started by a rotating electric machine such as a starter motor. At this time, since the viscosity of the lubricating oil of the engine varies depending on the temperature state of the engine, the torque required for the starter motor varies depending on the temperature state of the engine.

  Japanese Patent Laid-Open No. 2001-159384 (Patent Document 2) discloses an engine starter that can be started smoothly and stably even when the engine is in either a low temperature state or a high temperature state. An engine starting device described in Patent Document 2 is coupled to an output shaft of an engine, and is coupled to a first electric motor that outputs a low torque within a range in which an engine in a high temperature state can be smoothly started, and an output shaft, and is in a low temperature state. And a second electric motor that outputs a high torque sufficient to start the engine.

According to the engine starter described in this publication, the first motor suitable for starting in a high temperature state and the second motor suitable for starting in a low temperature state can be provided, while reducing the size of the device. It is possible to start the engine smoothly and stably under the operating conditions.
JP 2003-184553 A JP 2001-159384 A

  However, Japanese Patent Application Laid-Open No. 2003-184553 has no description regarding the torque of the rotating electrical machine required at the time of starting the engine. Therefore, it is difficult to apply the engine starting device described in Japanese Patent Laid-Open No. 2001-159384 to a vehicle including the heat storage device described in Japanese Patent Laid-Open No. 2003-184553. In addition, the engine starter described in Japanese Patent Application Laid-Open No. 2001-159384 is provided in a vehicle provided with a plurality of rotating electrical machines connected to a rotating shaft of an engine, such as a hybrid vehicle that can be driven by the driving force of the engine and the rotating electrical machine. Is preferred. However, in a vehicle that travels using only the driving force from the engine, at least two rotating electrical machines are required to start the engine, which may increase the cost and impair the degree of freedom of device layout.

  The present invention has been made to solve the above-described problems, and its object is to reduce the temperature and the temperature of the lubricating oil of the internal combustion engine while suppressing an increase in cost and impairing the degree of freedom of equipment layout. It is an object of the present invention to provide a control device for a rotating electrical machine that can start an internal combustion engine with an appropriate torque according to the requirements.

  According to a first aspect of the present invention, there is provided a control device for a rotating electrical machine, wherein a storage means for keeping a part of a liquid medium circulating in a flow path provided in an internal combustion engine is kept warm, a liquid medium in the storage means is stored in the storage means, A rotating electrical machine for starting the internal combustion engine is controlled in a vehicle equipped with a circulation means for circulating between the internal combustion engines. The control device includes means for detecting the temperature of the lubricating oil of the internal combustion engine, and control means for controlling the rotating electric machine so as to change the torque generated from the rotating electric machine based on the temperature of the lubricating oil of the internal combustion engine. Including.

  According to the first aspect of the present invention, in the vehicle equipped with the circulation means for circulating the liquid medium in the storage means between the storage means and the internal combustion engine, the internal combustion engine is started by the liquid medium in the storage means. The temperature of the lubricating oil at times can change. When the temperature of the lubricating oil is high, the friction of the internal combustion engine is low because the viscosity of the lubricating oil is lower than when the temperature is low. Therefore, the torque required for the rotating electrical machine for starting the internal combustion engine is low. Therefore, for example, when the temperature of the lubricating oil of the internal combustion engine is high, the torque generated from the rotating electrical machine is made lower than when the temperature is low. Thus, the rotating electrical machine can be driven with an appropriate torque according to the temperature of the lubricating oil of the internal combustion engine without providing a plurality of rotating electrical machines having different output torques. Therefore, a control device for a rotating electrical machine capable of starting an internal combustion engine with an appropriate torque according to the temperature of the lubricating oil of the internal combustion engine while suppressing an increase in cost and impairing the degree of freedom of equipment layout is provided. be able to.

  In the control apparatus for a rotating electrical machine according to the second aspect of the invention, in addition to the configuration of the first aspect, the control means causes the rotating electrical machine to lower the torque when the temperature of the lubricating oil is high than when it is low. Means for controlling.

  According to the second invention, when the temperature of the lubricating oil of the internal combustion engine is high, the viscosity of the lubricating oil is lower than when the temperature is low, so the friction of the internal combustion engine is low. Therefore, the torque required for the rotating electrical machine for starting the internal combustion engine is low. Therefore, when the temperature of the lubricating oil of the internal combustion engine is high, the torque generated from the rotating electrical machine is made lower than when the temperature is low. Thus, the rotating electrical machine can be driven with an appropriate torque according to the temperature of the lubricating oil of the internal combustion engine without providing a plurality of rotating electrical machines having different output torques.

  In the control apparatus for a rotating electrical machine according to the third invention, in addition to the configuration of the first or second invention, the control apparatus further includes means for detecting the rotational speed of the internal combustion engine. The control means includes means for controlling the rotating electrical machine so as to change the torque based on the rotational speed of the internal combustion engine in addition to the temperature of the lubricating oil of the internal combustion engine.

  According to the third invention, when the torque generated from the rotating electrical machine is insufficient, the rotational speed of the internal combustion engine does not increase to a predetermined rotational speed, and the internal combustion engine may not be started. Therefore, for example, when the rotational speed of the internal combustion engine is lower than a predetermined rotational speed, the torque generated from the rotating electrical machine is increased. As a result, the rotating electrical machine can be driven with an appropriate torque, and the internal combustion engine can be started quickly.

  In the control apparatus for a rotating electrical machine according to the fourth invention, in addition to the configuration of the third invention, the control means increases the torque when the rotational speed of the internal combustion engine is lower than a predetermined rotational speed. Means for controlling the rotating electrical machine are included.

  According to the fourth invention, when the rotational speed of the internal combustion engine does not increase to a predetermined rotational speed, it can be said that the torque of the rotating electrical machine is insufficient. In this case, the torque generated from the rotating electrical machine is increased. Thereby, the rotating electrical machine can be driven with an appropriate torque.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  With reference to FIG. 1, the control block diagram of the thermal storage system which is a control object of the control apparatus which concerns on this Embodiment is shown.

  The heat storage system shown in FIG. 1 is applied to a vehicle equipped with an internal combustion engine (engine). This vehicle may be a vehicle equipped only with an engine or a hybrid vehicle equipped with an engine and a motor driven by a battery.

This engine is started by being cranked by the starter 700 when the driver sets the ignition switch to the start position. Further, for such engine start, restart after the engine is temporarily stopped at idling stop is performed in the same manner. The idling stop system automatically stops the engine when the vehicle stops at a red light at an intersection or the like, and restarts the engine when the driver operates to start running again. For example, the accelerator opening is 0, 1 second or more has elapsed after the shift operation, the vehicle speed is 0, the engine speed is 1000 rpm or less, and the vehicle stops on the uphill or downhill road. If the engine coolant temperature is within a predetermined range, idling stop is permitted and the engine is temporarily stopped. Thereafter, when the idling stop condition is not satisfied, the engine is restarted.

  As shown in FIG. 1, this heat storage system keeps a part of cooling water flowing through a cooling water flow path provided in a cylinder head (hereinafter referred to as a head) 100 and a cylinder block 110 in a heat storage tank 310. The cooling water is stored and supplied to the head 100 and the cylinder block 110 from the heat storage tank 310 as necessary. Cooling water is circulated by the mechanical water pump 200 between the head 100 and the cylinder block 110 and the radiator 400 or the radiator bypass passage 410. The flow rate control valve 430 controls which of the radiator 400 and the radiator bypass passage 410 passes through. The mechanical water pump 200 receives a driving force from a crankshaft of the engine via a belt. Therefore, the mechanical water pump 200 serves as engine friction.

  Cooling water is supplied from the heat storage tank 310 to the head 100 and the cylinder block 110 by the electric water pump 300. By driving the electric water pump 300, the cooling water (hot water or cold water) in the heat storage tank 310 is supplied to the head 100, the cylinder block 110, the heater core 500, etc. via the three-way valve 610. . The three-way valve 610 is in a fully closed state, a fully open state (port A, port B and port C are in communication), port A and port B are in communication, port A and port C are in communication, port B and port C Can be realized in five different states.

  Further, as temperature sensors of this heat storage system, an engine coolant temperature sensor 120 provided on the coolant outlet side of the head 100, a heat storage tank outlet temperature sensor 320 provided on the outlet side of the heat storage tank 310, and a radiator 400 A radiator outlet water temperature sensor 420 provided at the outlet is provided. Signals from these temperature sensors are input to an engine ECU (Electronic Control Unit) 1000.

  Further, engine ECU 1000 receives a signal representing engine speed NE from a crank position sensor 1010 provided to face the outer periphery of a timing rotor that rotates integrally with the crankshaft of the engine.

  The engine ECU 1000 controls the electric water pump 300, the three-way valve 610, and the flow control valve 430. The flow rate control valve 430 can control the flow rate of the cooling water flowing through the radiator 400 and the flow rate of the cooling water flowing through the radiator bypass passage 410 by changing the control duty. At this time, the flow rate control valve 430 can flow cooling water only to the radiator 400, only to the radiator bypass passage 410, and to the radiator 400 and the radiator bypass passage 410. When the flow control valve 430 receives a fully open command signal from the engine ECU 1000, the flow control valve 430 controls the flow rate so that the entire amount of cooling water flows to the radiator 400. Further, when the flow control valve 430 receives a full-close command signal from the engine ECU 1000, the flow control valve 430 controls the flow rate so that the entire amount of cooling water flows through the radiator bypass passage 410. Further, the flow control valve 430 can receive a command signal from the engine ECU 1000 and control the flow rate so that a part of the cooling water flows to the radiator 400 and the remaining cooling water flows to the radiator bypass passage 410. .

  Further, engine ECU 1000 can control the discharge rate of electric water pump 300 by changing the control duty of the motor that drives electric water pump 300 to control the number of revolutions of the motor. Further, this control may be performed by making the voltage of the motor of the electric water pump 300 variable. Further, by changing the energization time of the motor of the electric water pump 300, the driving time of the electric water pump 300 is controlled to control the total amount of cooling water discharged from the electric water pump 300. Good.

  Further, engine ECU 1000 controls converter 702 that adjusts the drive voltage of starter 700 to change the drive voltage of starter 700, thereby changing the torque of starter 700. Note that the method of changing the torque of the starter 700 is not limited to this.

  A control structure of a program executed by engine ECU 1000 of FIG. 1 will be described with reference to FIG.

  In step (hereinafter step is abbreviated as S) 100, engine ECU 1000 determines whether an engine start request has been detected. For example, the start request is detected by the driver operating the ignition switch to the engine start position, or the idling stop condition is not satisfied during the idling stop, and the restart request is detected. Hereinafter, such a start including the restart from the idling stop is referred to as a start. If an engine start request is detected (YES in S100), the process proceeds to S102. If not (NO in S100), the process returns to S100 and waits until an engine start request is detected.

  In S102, engine ECU 1000 detects engine coolant temperature THW (1) based on the signal transmitted from engine coolant temperature sensor 120, and based on the signal transmitted from heat storage tank outlet temperature sensor 320, The heat storage tank water temperature THW (2) is detected.

  In S104, engine ECU 1000 determines whether or not the cooling water in heat storage tank 310 is supplied to cylinder block 110. Whether or not the coolant in the heat storage tank 310 is supplied to the cylinder block 110 is determined by the engine ECU 1000 itself based on, for example, a map stored in a memory (not shown). Therefore, whether or not the cooling water in heat storage tank 310 is supplied to cylinder block 110 is determined inside engine ECU 1000. If cooling water in heat storage tank 310 is being supplied to cylinder block 110 (YES in S104), the process proceeds to S106. If not (NO in S104), the process proceeds to S108.

  In S106, engine ECU 1000 estimates the amount of cooling water supplied from heat storage tank 310 to cylinder block 110. What is necessary is just to estimate the quantity of the cooling water supplied to the cylinder block 110 from the thermal storage tank 310 based on the drive time of the electric water pump 300, and the opening degree of each port in the three-way valve 610, for example.

  In S108, engine ECU 1000 estimates the oil temperature (engine oil temperature) in cylinder block 110. When cooling water is supplied from heat storage tank 310 to cylinder block 110 (YES in S104), the oil temperature is estimated based on the amount of heat transferred from cooling water to cylinder block 110. The amount of heat transferred to the cylinder block 110 is estimated based on the amount of cooling water supplied to the cylinder block 110 and the heat storage tank water temperature THW (2). The temperature difference obtained by subtracting the engine coolant temperature THW (1) from the heat storage tank water temperature THW (2) is supplied to the cylinder block 110 and the value obtained by adding the heat capacity of the cylinder block 110 to the amount of coolant in the cylinder block 110 The amount of heat transferred from the cooling water in the heat storage tank 310 to the cylinder block 110 is estimated by dividing by a coefficient representing the ratio to the amount of the cooling water that has been performed. The relationship between the amount of heat and the amount of increase in oil temperature is measured in advance through experiments or the like, and the measurement result is stored in a memory as a map. Add to the estimated oil temperature to estimate the final oil temperature.

  On the other hand, when cooling water is not supplied from heat storage tank 310 to cylinder block 110 (NO in S104), the oil temperature is estimated based on engine cooling water temperature THW (1). For example, the relationship between the engine coolant temperature THW (1) and the oil temperature is measured in advance through experiments or the like, the measurement result is stored in a memory as a map, and the oil temperature is estimated from this map. Note that the method of estimating the amount of heat transmitted to the head 100 and the oil temperature is not limited thereto.

  In S110, engine ECU 1000 estimates engine friction based on the estimated oil temperature. For example, the relationship between the oil temperature and the friction is measured in advance through experiments or the like, the measurement result is stored in a memory as a map, and the friction is estimated based on this map. The method for estimating the friction is not limited to this.

  In S112, engine ECU 1000 determines the drive voltage of starter 700 based on the estimated friction. The drive voltage of starter 700 is determined according to a map stored in a memory, for example. When the friction is small, that is, when the oil temperature is high, the drive voltage of the starter 700 is set to a lower voltage than when the oil temperature is low. Thereby, when the oil temperature is high, the torque of the starter 700 is made lower than when the oil temperature is low. If the oil temperature is too high, the viscosity of the lubricating oil may be lower than the viscosity necessary for lubrication, and conversely, the friction may increase. Therefore, when the oil temperature is higher than a predetermined oil temperature, the drive voltage of starter 700 may be increased to increase the torque.

  In S114, engine ECU 1000 drives starter 700 to start engine cranking. In S116, engine ECU 1000 detects engine speed NE based on the signal transmitted from crank position sensor 1002.

  In S118, engine ECU 1000 determines whether engine speed NE is equal to or greater than a predetermined threshold value NE (0). If engine speed NE is equal to or greater than threshold value NE (0) (YES in S118), the process proceeds to S120. If not (NO in S118), the process proceeds to S122.

  In S120, engine ECU 1000 ignites the air-fuel mixture in the combustion chamber with the spark plug and starts the engine. In S122, engine ECU 1000 increases the drive voltage of starter 700. Thereafter, the process returns to S118.

  The operation of the control device for the heat storage system according to the present embodiment based on the above-described structure and flowchart will be described.

  If the driver operates the ignition switch to the engine start position or the idling stop condition is not satisfied while the engine is stopped, an engine start request is detected (YES in S100). When an engine start request is detected (YES in S100), engine cooling water temperature THW (1) is detected, and heat storage tank water temperature THW (2) is detected (S102).

  When starting the engine, high-temperature cooling water in the heat storage tank 310 may be supplied to the head 100 or the cylinder block 110 in order to improve the startability of the engine or improve the exhaust emission performance. is there.

  The temperature of the head 100 and the cylinder block 110 can be changed by the cooling water in the heat storage tank 310. In particular, when the temperature of the cylinder block 110 changes, the oil temperature changes. In order to accurately estimate the oil temperature, when the cooling water in heat storage tank 310 is supplied to cylinder block 110 (YES in S104), the amount of cooling water supplied from heat storage tank 310 to cylinder block 110 is estimated. (S106). Based on the estimated amount of cooling water and heat storage tank water temperature THW (2), the amount of heat transferred from the cooling water in heat storage tank 310 to cylinder block 110 is estimated, and the oil temperature is estimated from this amount of heat (S108). ). On the other hand, when the cooling water is not supplied from the heat storage tank 310 to the cylinder block 110, the oil temperature is estimated based on the engine cooling water temperature THW (1) (S108). Thereby, the oil temperature can be accurately estimated according to the supply state of the cooling water from the heat storage tank 310.

  Further, the engine friction is estimated from the estimated oil temperature (S110), and the drive voltage of the starter 700 is determined so that the torque can be cranked and started at the estimated friction. (S112). Therefore, the lower the friction, that is, the higher the oil temperature, the lower the drive voltage of the starter 700 and the lower the torque. Thereby, the power consumption of the starter 700 can be suppressed in a state where the oil temperature is high, and ultimately the fuel consumption can be improved.

  The starter 700 is driven with the determined drive voltage, and the engine is cranked (S114). When the engine is cranked, the engine speed NE is detected (S116).

  When engine speed NE rises due to cranking and engine speed NE exceeds threshold value NE (0) (YES in S118), the air-fuel mixture in the cylinder is ignited by the spark plug, and the engine is started. (S120).

  On the other hand, if the estimated friction is estimated to be smaller than the actual friction and the drive voltage of the starter 700 is insufficient, the engine speed NE does not increase to the number of revolutions necessary to start the engine, and the engine Cannot be started. Therefore, when engine speed NE is smaller than threshold value NE (0) (NO in S118), drive voltage of starter 700 is increased (S122), and torque of starter 700 is increased. As a result, the engine can be reliably cranked and the engine can be started.

  As described above, the engine ECU of the heat storage system according to the present embodiment lowers the torque by lowering the drive voltage of the starter when the oil temperature is high than when the oil temperature is low. Accordingly, the engine can be cranked and started with an appropriate torque according to the oil temperature without providing a plurality of rotating electrical machines such as a starter and a motor generator. Therefore, it is possible to start the engine with an appropriate torque corresponding to the oil temperature while suppressing an increase in cost and a loss in the degree of freedom of device layout. In particular, when the oil temperature is high, the power consumed by the starter can be suppressed, and ultimately the fuel consumption can be improved.

  In addition, although this Embodiment demonstrated the vehicle carrying a thermal storage system and an idling stop system, in the vehicle which is not equipped with a thermal storage system or an idling stop system, the drive voltage (torque) of the starter 700 according to oil temperature May be changed.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a control block diagram of the heat storage system which concerns on embodiment of this invention. It is a figure which shows the flowchart which shows the control structure of the program performed by engine ECU of FIG.

Explanation of symbols

  100 Cylinder Head, 110 Cylinder Block, 120 Engine Cooling Water Temperature Sensor, 200 Mechanical Water Pump, 300 Electric Water Pump, 310 Thermal Storage Tank, 320 Thermal Storage Tank Outlet Temperature Sensor, 400 Radiator, 410 Radiator Bypass Path, 420 Radiator Outlet Water Temperature Sensor, 430 Flow control valve, 500 Heater core, 610 Three-way valve, 620 Heater valve, 700 Starter, 1000 Engine ECU, 1010 Crank position sensor.

Claims (4)

A storage means for keeping a part of the liquid medium circulating in a flow path provided in the internal combustion engine to keep warm, and a circulation for circulating the liquid medium in the storage means between the storage means and the internal combustion engine A control device for a rotating electrical machine that starts the internal combustion engine in a vehicle equipped with means,
Means for detecting the temperature of the lubricating oil of the internal combustion engine;
And a control unit for controlling the rotating electrical machine so as to change a torque generated from the rotating electrical machine based on a temperature of lubricating oil of the internal combustion engine.   The control of the rotating electrical machine according to claim 1, wherein the control means includes means for controlling the rotating electrical machine so that the torque is lowered when the temperature of the lubricating oil is high compared to when the temperature is low. apparatus. The control device further includes means for detecting the rotational speed of the internal combustion engine,
The control means includes means for controlling the rotating electrical machine so as to change the torque based on the rotational speed of the internal combustion engine in addition to the temperature of the lubricating oil of the internal combustion engine. The control apparatus of the rotary electric machine described.   The rotating electrical machine according to claim 3, wherein the control means includes means for controlling the rotating electrical machine to increase the torque when the rotational speed of the internal combustion engine is lower than a predetermined rotational speed. Control device.

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