JP4075812B2 - Coordinated control device for vehicle - Google Patents

Description

  The present invention relates to a vehicle cooperative control device that cooperatively controls an internal combustion engine mounted on a vehicle, and a generator and an air conditioner that are driven by the output of the internal combustion engine.

A vehicle that stores cold energy generated by an air conditioner and electric energy generated by an alternator is described in the following [Patent Document 1]. In the vehicle described above, the fuel efficiency is improved by controlling the air conditioner and the alternator according to the traveling state during the regeneration control. Examples of the running state include outside air temperature, solar radiation conditions, road gradient information and altitude information obtained by a navigation system.
JP 2002-36903 A

  Energy (cooling / electricity) is generated in the air conditioner and alternator using the output of the engine. For this reason, when energy is generated by an air conditioner or an alternator, the vehicle driving force is reduced accordingly. In the apparatus described in [Patent Document 1], as described above, energy efficiency is improved by controlling accumulation and release of energy generated by an air conditioner and an alternator during regenerative control. Improvement is desired. An object of the present invention is to provide a cooperative control device for a vehicle that can improve energy efficiency by storing energy.

A vehicle cooperative control device according to claim 1 is an internal combustion engine mounted on a vehicle, a generator that generates electric power using the output of the internal combustion engine, an air conditioner that is driven using the output of the internal combustion engine, and a generator Energy storage means for storing the electric energy generated by the engine and the cold energy generated by the air conditioner, environmental condition acquisition means for acquiring the traveling environment condition on the traveling route of the vehicle, and driving of the internal combustion engine, the generator and the air conditioner And cooperative control means for controlling in a coordinated manner. Then, the cooperative control means regenerates a period in which power generation by the generator or cold generation by the air conditioner can be generated based on the traveling environment situation acquired by the environment situation acquisition means and the energy amount stored in the energy storage means. If the regenerative period is less than the predetermined time, power generation using the generator is prioritized over cold generation using the air conditioner during the regeneration period.
According to a second aspect of the present invention, in the vehicle cooperative control device according to the first aspect, the predetermined time used by the cooperative control means is set based on a temperature state of the air conditioner.
According to a third aspect of the present invention, in the vehicle cooperative control device according to the first or second aspect, the predetermined time used by the cooperative control means is set based on an outside air temperature.

According to a fourth aspect of the present invention, in the vehicle cooperative control device according to any one of the first to third aspects, the cooperative control means predicts a load situation of the internal combustion engine based on the traveling environment situation, and It is characterized by predicting the regenerative period based on the load situation prediction.

According to a fifth aspect of the present invention, in the vehicle cooperative control device according to any one of the first to fourth aspects, the environmental status acquisition means includes an intersection position, a signal position / crossing position, a road gradient, It is characterized in that at least one of the road curve curvature and the presence / absence of traffic jam is acquired as a traveling environment situation.

In the vehicle cooperative control device according to the first aspect, when the regenerative available time is less than the predetermined time, the generation of electric energy by the generator is given priority over the generation of cold energy by the air conditioner. When regeneration is performed by generating cold energy by the air conditioner, the air conditioner compressor is driven using the output of the internal combustion engine. However, compared with regeneration by power generation by a generator such as an alternator, regeneration by an air conditioner has poor responsiveness due to the characteristics of the compressor, and regeneration efficiency (energy efficiency) is not good in a short time operation. Therefore, as described above, when the regenerative time is less than the predetermined time, the generation of electrical energy by the generator is prioritized over the generation of cold energy by the air conditioner to improve the energy efficiency.
According to the second aspect of the present invention, it is possible to determine in more detail whether the predetermined time used by the cooperative control means is varied based on the temperature state of the air conditioner, which leads to improvement in energy efficiency.
According to the third aspect of the present invention, it is possible to determine in more detail whether the predetermined time used by the cooperative control means is further varied based on the outside air temperature, which leads to improvement in energy efficiency.

According to the invention described in claim 4 , the cooperative control means predicts the load situation of the internal combustion engine based on the traveling environment situation, and predicts the regeneration possible period based on the load situation prediction. Thus, the prediction accuracy of the regeneration possible time can be improved by predicting the regeneration possible time based on the load situation prediction based on the traveling environment situation. If the prediction accuracy of the regenerative time is improved, the accuracy of the above-described priority control is improved, and the energy efficiency can be further improved.

According to the fifth aspect of the present invention, the environmental condition acquisition means obtains at least one of information on the position of the intersection, the position of the signal / the level crossing, the road gradient, the road curve curvature, and the presence / absence of traffic congestion. Get as. Since these pieces of information have a great influence on whether or not regeneration is possible, it is possible to improve the prediction accuracy of the period during which regeneration is possible by acquiring these pieces of information as travel environment conditions.

  An embodiment of the control device of the present invention will be described below. The main components of a vehicle having the control device of this embodiment are shown in FIG. The driving force that drives the vehicle 1 is generated by the engine 2 that is an internal combustion engine. The engine 2 itself is a known general engine. The output of the engine 2 is transmitted to drive wheels via a transmission 3 and a differential gear (not shown) to drive the vehicle 1. Further, an alternator (generator) 4 that is driven by utilizing a part of the output of the engine 2 and a compressor 6 of the air conditioner 5 are attached to the engine 2. The alternator 4 and the compressor 6 are auxiliary machines that generate energy using the output of the engine 2.

  The alternator 4 is an AC generator, and includes a rectifier that rectifies the generated AC current into a DC current and an IC regulator that adjusts the voltage to obtain a constant output, and outputs DC power. The electric power generated by the alternator 4 is used as it is by the engine 2 and other auxiliary machines as well as for charging the battery 7. That is, the battery 7 stores the electric energy generated by the alternator 4. The alternator 4 can control the power generation amount by controlling the excitation current.

  The air conditioner 5 introduces air cooled by a heat exchanger 8 serving as a heat source or air heated by a heater core (not shown) serving as a heat source into the vehicle interior by a blower fan 9, thereby cooling and heating the vehicle interior. (Or dehumidification). In the air conditioner 5, one refrigerant circulation system is formed by the compressor 6, the condenser 10, the cool storage unit 12 of the heat accumulator 11, and the compressor 6. Further, another circulation system is formed between the cold storage unit 12 and the heat exchanger 8. That is, the cold generated by the air conditioner 5 is temporarily stored in the cold storage unit 12, and the cold heat of the cold storage unit 12 is introduced into the vehicle via the heat exchanger 8.

  Although the cold storage part 12 mentioned above is a part which stores the produced | generated cold heat, the thermal storage 11 is provided with the warm storage part 13 which stores warm heat. The warm storage unit 13 has a circulation system in which the coolant of the engine 2 is branched and circulated, and stores the heat of the coolant. Moreover, the warm storage part 13 has another circulation system between the heater core (not shown) mentioned above. That is, the warm storage unit 13 temporarily stores the warm heat of the coolant of the engine 2, and the warm heat of the warm storage unit 13 is introduced into the vehicle via the heater core. The heat storage unit 12 and the battery 7 described above function as a storage device (energy storage unit) 14 that stores energy.

  The generation of cold heat in the air conditioner 5 will be briefly described. The refrigerant is compressed by the compressor 6, the heat is taken away by the condenser 10, and the refrigerant is liquefied. The expansion valve built in the regenerator 12 makes it easy to vaporize the refrigerant, and the regenerator 12 vaporizes the refrigerant The regenerator material inside the regenerator 12 is cooled by the heat of vaporization at this time. The cold storage unit 12 accumulates cold heat by keeping the temperature of the internal cold storage material low. The refrigerant discharged from the cold storage unit 12 is compressed again by the compressor 6 and circulates repeatedly through the compressor 6 -the condenser 10 -the cold storage unit 12 described above.

  Further, the inside of the circulation pipe between the cold storage unit 12 and the heat exchanger 8 is also filled with the refrigerant, and the cold heat stored in the cold storage unit 12 is transmitted to the heat exchanger 8 in the passenger compartment by the circulation of the refrigerant. It is done. The cold heat of the heat exchanger 8 is introduced into the vehicle interior by the blower fan 9 described above. As the refrigerant filled in the circulation pipe between the cold storage section 12 and the heat exchanger 8 described above, liquid such as water, brine (brine), ethylene glycol solution, or gas such as carbon dioxide is used. The cold storage unit 12 includes a temperature sensor that detects an internal cold storage material temperature and a refrigerant temperature. The heat exchanger 8 also has a built-in temperature sensor.

  The above-described compressor 6 of the present embodiment is of an externally controlled variable displacement type, and can continuously variably control the refrigerant compression and discharge amount by an external signal (DUTY signal). The structure is of a known general swash plate type, and the capacity is changed by changing the inclination of the swash plate. The compressor 6 can have a capacity of zero so that the refrigerant is not discharged, and does not require a clutch or the like.

  The alternator 4 described above is connected to an electronic control unit (ECU) 15 that controls the engine 2, and its power generation amount is variably controlled. The above-described compressor 6 is connected to an air conditioner ECU 16 that controls the air conditioner 5, and the refrigerant protrusion amount (compressor capacity) is variably controlled. The engine ECU 15 and the air conditioner ECU 16 are connected to an integrated ECU 17 that comprehensively controls various controls of the entire vehicle 1. The ECUs 15 to 17 coordinate the control of the engine 2, the power generation control by the alternator 4, and the air conditioning control by the air conditioner 5. The battery 7 is also connected to the integrated ECU 17, and the voltage of the battery 7 is monitored by the integrated ECU 17.

  Furthermore, the temperature sensor built in the cool storage unit 12 described above is also connected to the air conditioner ECU 16, and the refrigerant temperature of the cool storage unit 12 is monitored by the air conditioner ECU 16. A wheel speed sensor 18 and an outside air temperature sensor 19 are also connected to the integrated ECU 17. The wheel speed sensor 18 is attached to each wheel and detects the number of rotations of each wheel. The speed of the vehicle 1 can also be detected from the detection result of the wheel speed sensor 18. The outside air temperature sensor 19 detects the temperature outside the vehicle.

  The air conditioner ECU 16 is also connected with a vehicle interior temperature sensor 20 for detecting the temperature in the vehicle interior and an operation panel 21. The operation panel 21 sets a set temperature, a blowing mode, an air volume, and the like. Further, the engine ECU 15 is also connected to a navigation system 22 mounted on the vehicle 1. The navigation system 22 incorporates a storage medium such as a hard disk or a DVD disk that stores road / terrain information and other information (facility information, etc.). The information in this recording medium is information (running environment status) regarding non-variable intersections (signals), presence / absence of level crossings, road gradient (terrain), altitude, etc. that do not change in a short time. In addition, the navigation system 22 has a communication function, and can acquire from the outside of the vehicle 1 a traveling environment situation that can fluctuate in a short time, such as weather (weather) or a traffic jam situation. The non-variable driving environment information described above may be acquired by the communication function.

  The communication function may be a communication function that completes itself, such as a dedicated communication interface, or may use a mobile phone or the like. Furthermore, so-called VICS, optical beacons, FM communication, and the like are one of the communication functions described here. Moreover, if the destination is set, it is also possible to acquire travel environment information over the entire section of this route along with the recommended route. In addition, the own vehicle position of the vehicle 1 can be detected using GPS, a gyro, or the like. The engine ECU 15 can acquire the above-described traveling environment situation from the navigation system 22 as information. The navigation system 22 functions as an environmental status acquisition unit.

  Next, control using the above-described apparatus will be described. The control flowchart by this embodiment apparatus is shown in FIG.2 and FIG.3. First, as shown in FIG. 2, it is determined whether or not the air conditioner 5 is in operation (requires cooling) (step 200). Here, the case where the air conditioner 5 is used as a heater is not included. The output of the engine 2 is consumed when the refrigerant is circulated by the compressor 6 of the air conditioner 5 to generate cold. The control of the present embodiment device is to coordinate the power generation by the alternator 4 using the output of the engine 2 and the cold heat generation by the air conditioner 5. Therefore, “in operation of the air conditioner” mentioned here does not include the case where the air conditioner 5 is used as a heater.

  If step 200 is negative and the air conditioner 5 does not require generation of cold, only the power generation by the alternator 4 may be considered, and the operation of the alternator 4 is prioritized (step 205). The determination of the priority status is stored in a memory of the integrated ECU 17 using a flag or the like. Next, the traveling environment situation described above is acquired (step 210). This traveling environment situation includes the non-variable and the variable described above. Non-fluctuating driving environment conditions that do not fluctuate in a short time include information on intersections (signals), the presence / absence of railroad crossings, road gradients, etc., and driving environment conditions that can fluctuate in a short time include weather (weather) and traffic congestion As described above, information on the situation and the like is included.

  These traveling environment situations are acquired by the navigation system 22 (including the case where the navigation system 22 itself stores it). That is, the navigation system 22 functions as environmental status acquisition means. The non-variable environmental situation can be stored by the navigation system 22 itself, and can be acquired from the outside by the communication function of the navigation system 22. The variable driving environment situation is acquired by communication with the outside of the vehicle 1 by the communication function.

  Here, various vehicle environmental conditions may be acquired. The vehicle environmental conditions include the inside temperature, the outside temperature, the amount of solar radiation, the air conditioner set temperature, and the like. These values are detected by the vehicle interior temperature sensor 20, the outside air temperature sensor 19, and the solar radiation sensor (not shown). As for the set temperature, the air conditioner ECU 16 detects an operation by the air conditioner operation panel 21. When the traveling environment situation is acquired, the engine load in the fixed traveling direction section is predicted based on the traveling environment situation (and the vehicle environment condition) (step 215). Here, the engine load is applied to a certain section in the traveling direction. However, when the destination is set by the navigation system 22 and the route to the destination is determined, The engine load prediction for the section may be performed.

  For example, FIG. 4 shows a map used when determining the engine load from a road gradient (an example of a traveling environment situation). Here, such a map is created in advance through experiments or the like, and the engine load is obtained from such a map. When there are a plurality of various situations and conditions, the map as shown in FIG. Further, FIG. 5A shows a change in altitude (another example of the driving environment state) within the above-described fixed section, and FIG. 5B shows a change in engine load α with respect to this altitude change. Then, after the engine load is predicted, a regeneration possible period is predicted (step 220). The regenerative period is a period in which there is a margin in the output of the engine 2 (in this case, it is determined whether or not there is a margin based on the fuel consumption), and power generation by the alternator 4 and cold generation by the air conditioner 5 can be performed. Say.

  This step 220 is performed by the subroutine shown in FIG. This control will be described with reference to FIG. First, the engine load α [see FIG. 5B] predicted in step 215 of the flowchart of FIG. 2 is read (step 300). After step 300, based on the driving environment situation (and vehicle environmental conditions), the load amount that minimizes the fuel consumption is calculated as the margin load amount β (step 305). This marginal load amount β is also shown in FIG. That is, in FIG. 5B, when the marginal load amount β line is above the predicted engine load α, the fuel consumption is minimized even if the necessary engine load α is output. It can be said that the engine 2 can be operated and the load (torque) can be spared.

  FIG. 5C shows a change with time of (α−β), and the lowest line on which the compressor 6 should be operated is also shown on this graph. When the margin is small, it is conceivable that the engine load α is changed by operating the compressor 6 so that the margin is not actually generated. Therefore, when the margin is small, the compressor 6 is not operated, and the above-described minimum line is set as this threshold value. After step 305, t1 and t2 in FIG. 5 (c), which are regenerative periods, are obtained (step 310). Each regeneration possible period is one continuous period in which (α−β) exceeds the above-described minimum line. That is, the section of t1 and t2 is a period (duration) during which the compressor 6 of the air conditioner 5 can be operated.

  Next, after step 310, it is determined at each continuation time t whether the length exceeds a predetermined determination value (step 315). If step 315 is negative, that is, if the regenerative time is shorter than the predetermined time, the operation of the alternator is prioritized (step 330). This is because the regeneration by the compressor 6 is not efficient unless it is continued to some extent, and when the duration is short, the drive of the compressor 6 is suppressed to suppress a decrease in efficiency. This determination value is determined using the map of FIG. A plurality of curves in the map of FIG. 6 are isothermal curves, and a curve to be used is determined according to the outside air temperature. The higher the outside air temperature, the more the upper curve is applied. The vertical axis represents the temperature difference between the regenerator temperature of the regenerator 12 and the temperature of the refrigerant flowing into the regenerator 12, and the horizontal axis represents the determination value ts. That is, under a constant outside air temperature condition, the determination value ts is set to be smaller as the above-described temperature difference is larger (the temperature of the inflowing refrigerant is sufficiently lower than the cool storage material temperature), and the compressor is more easily operated. Further, if the temperature difference is the same, the determination value ts is set to be larger as the outside air temperature is higher.

  On the other hand, when step 315 is affirmed, it is then determined whether or not the cold storage amount is less than a predetermined determination value (step 320). This determination value may be fixedly determined in advance, or may be variably determined based on the vehicle environmental conditions described above. Further, this determination value may be corrected as needed by learning performed based on vehicle environmental conditions. Note that the amount of cold heat calculated in step 225, which will be described later, is stored in the memory of the air conditioner ECU 16, and is determined based on this value. Alternatively, it may be newly calculated here.

  If step 320 is negative, it can be determined that a sufficient amount of cold energy has been accumulated, so it is considered that the necessity of generating cold energy by driving the compressor 6 is low. Further, as described above, the regeneration efficiency by the compressor 6 is often inferior to the regeneration efficiency by the alternator 4. Therefore, even when step 230 is denied, the operation of the alternator is prioritized (step 330). On the other hand, if step 320 is affirmed, it can be determined that the regenerative efficiency can be sufficiently secured even if the compressor 6 generates cold heat, and that the accumulated amount of cold heat is reduced. Gives priority to the operation of the compressor 6 (step 325). If it is already determined in step 205 that the alternator 4 is prioritized, the determination in step 205 is prioritized.

  Since the description of the prediction of the regenerative period has ended, the process returns to step 225 in the flowchart of FIG. After step 220, the energy storage status in the storage device 14 is acquired (step 225). Below, the calculation method of the accumulation | storage state in the cool storage part 12 is shown. An explanatory diagram relating to this is shown in FIG. As shown in FIG. 7, the refrigerant temperature before the cold storage unit 12 is T1, the refrigerant temperature after the cold storage unit 12 is T1 ', the flow volume is M1, and the heat quantity of the refrigerant is Q1. Similarly, the temperature of the cold storage material in the cold storage unit 12 is T2, the volume thereof is M2, and the amount of heat of the cold storage material is Q2. Moreover, the temperature before the heat exchanger 8 of the refrigerant circulating between the cold storage unit 12 and the heat exchanger 8 is T3, the temperature after the heat exchanger 8 is T3 ′, and the flow volume is M3. Q3. Further, the temperature of the heat exchanger 8 is T4, and the air conditioning heat load is Q4 as described above.

If it does in this way, calorie | heat amount Q2 is shown by following formula (I) or formula (II). Formula (I) is for determining Q2 based on temperature, and Formula (II) is for determining Q2 based on the amount of heat. T2start is the temperature of the cold storage material in the initial (normal temperature) state.
Q2 = (T4-T2) × M2 (I)
Q2 = Q1-Q3-[(T2start-T4) * M2]
= [(T1′−T1) × M1] − [(T3′−T3) × M3] − [(T2start−T4) × M2] (II)

Next, a method for calculating the charged amount of the battery 7 will be described. An explanatory diagram relating to this is shown in FIG. When the voltage of the battery 7 is V, the stored energy is E, t1 to tn are the control time, i1 is the charging current of the battery 7, and i2 is the discharging current of the battery 7, the energy (storage amount) E is expressed by the following formula ( III).
E = [(i1-i2) * V * t1] + [(i1-i2) * V * t2] + ... + [(i1-i2) * V * tn] (III)

  After step 225, the operation interval between the alternator 4 and the compressor 6 is scheduled based on the regenerative period calculated in step 220 (and the priority status [steps 325, 330] and the accumulation state calculated in step 225). (Step 230) That is, it is scheduled which auxiliary machine is driven in which period, and how the power generation amount and compressor capacity at that time are to be performed (operation ratio). Based on the above, it is determined whether or not power storage / cold storage is actually possible (step 235), and if it is possible, the operating ratio is determined (step 240). The process is executed again from step 200 again.

  As described above, the regenerative efficiency of the compressor 6 has poor response due to the characteristics of the compressor 6 and does not sufficiently contribute to efficiency improvement in a short time. For this reason, here, when the length of one continuous regeneration possible period is shorter than the predetermined time, the operation of the alternator 4 is prioritized to improve the efficiency. At this time, the predetermined time is varied based on the state of the air conditioner 5 (the temperature of the refrigerant), and it is determined in more detail whether the efficiency is improved.

  In addition, the control apparatus of this invention is not limited to embodiment mentioned above. For example, the storage device (energy storage unit) 14 in the above-described embodiment includes the cold storage unit 12, the warm storage unit 13, and the battery 7. However, the cold storage unit, the warm storage unit, and the battery may be divided and mounted at different locations on the vehicle. Moreover, in embodiment mentioned above, although integrated ECU17, engine ECU15, and air-conditioner ECU16 share and control, the method of the sharing is not limited to embodiment mentioned above. Moreover, when using ECU for the control apparatus of this invention, it does not mean that the number must be three.

It is a block diagram which shows the structure of the vehicle which has one Embodiment of the control apparatus of this invention. It is a control flowchart by one Embodiment of the control apparatus of this invention. It is a flowchart of the regeneration possible period prediction control by one Embodiment of the control apparatus of this invention. It is an example of the map used for estimating an engine load from a driving | running | working environment condition (road gradient). (A) is a graph which shows the time change of a driving | running | working environment condition (altitude), (b) the time change of engine load (alpha) and margin load amount (beta), and (c) regeneration possible period. It is a map used at the time of determination value determination. It is explanatory drawing regarding energy storage amount (cold storage amount) calculation. It is explanatory drawing regarding energy storage amount (electric storage amount) calculation.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Vehicle, 2 ... Engine (internal combustion engine), 4 ... Alternator (generator), 5 ... Air conditioner, 6 ... Compressor, 7 ... Battery (energy storage means), 8 ... Heat exchanger, 9 ... Blower fan, 10 DESCRIPTION OF SYMBOLS ... Condenser, 11 ... Heat storage device (energy storage means), 12 ... Cold storage part (energy storage means), 15 ... Engine ECU (control means), 16 ... Air-conditioner ECU (control means), 17 ... Integrated ECU (control means), 22 Navigation system (environmental status acquisition means).

Claims (5)

An internal combustion engine mounted on the vehicle;
A generator for generating electricity using the output of the internal combustion engine;
An air conditioner driven using the output of the internal combustion engine;
Energy storage means for storing electric energy generated by the generator and cold energy generated by the air conditioner;
Environmental condition acquisition means for acquiring a driving environment condition on the driving route of the vehicle;
A cooperative control means for cooperatively controlling the driving of the internal combustion engine, the generator and the air conditioner;
Based on the traveling environment situation acquired by the environmental situation acquisition means and the amount of energy stored in the energy storage means, the cooperative control means has a period during which power generation by the generator or cold generation by the air conditioner can be generated. Predicting as a regenerative period, and if a single regenerative period is less than a predetermined time, power generation using the generator is given priority over cold generation using the air conditioner in the period. A vehicle cooperative control device. 2. The vehicle cooperative control device according to claim 1, wherein the predetermined time is set based on a temperature state of the air conditioner. The vehicle cooperative control device according to claim 1, wherein the predetermined time is set based on an outside air temperature in the cooperative control unit. The cooperative control means, based on the running environment conditions to predict the load condition of the internal combustion engine, according to claim 1 to 3 any one of which is characterized by predicting the regeneration period based on the load situation prediction The vehicle cooperative control device described in 1. The environmental condition acquisition means acquires at least one of information on the position of an intersection, the position of a signal / crossing of a road, road gradient, road curve curvature, and presence / absence of traffic jam as a driving environment condition. The cooperative control apparatus for vehicles as described in any one of 1-4 .

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