JP5321204B2 - Control device for hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for hybrid vehicle that suppresses inefficient fuel consumption to improve mileage by reducing timing separation between engine warm-up completion and battery charging completion at the cold start of the engine. <P>SOLUTION: The FR hybrid vehicle is equipped with an engine Eng and a motor/generator MG driven by power charged to a battery 4, and performs control to warm-up the engine by load driving at the cold start of the engines Eng. In the FR hybrid vehicle, an engine warm-up control means (Fig.2) predicts charging time of the battery 4 and warm-up time of the engine Eng at the cold start of the engine Eng, extracts operation points wherein engine warm-up completion timing and battery charging completion timing are within a predetermined range, and performs load operation by one of the extracted operation points. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a control apparatus for a hybrid vehicle that performs control for encouraging engine warm-up by load operation when the engine is cold-started.

  A hybrid vehicle equipped with a mode (hereinafter referred to as `` motor travel mode '') in which a vehicle travel engine (hereinafter referred to as `` engine '') is stopped and traveled only by a travel motor mounted on the vehicle is Due to problems with combustion stability and exhaust performance, idling stop is prohibited until the engine water temperature reaches a certain temperature. Therefore, a hybrid vehicle that has improved fuel efficiency by stopping an inefficient engine in a low-load travel region will deteriorate the fuel efficiency due to an increased number of opportunities for the engine to continue to rotate without load at the time of cold start. Therefore, warming up the engine early at the time of cold start is an important issue from the viewpoint of improving fuel efficiency.

  A hybrid vehicle is known to be able to warm up earlier by increasing the engine load and promoting heat generation by outputting the engine even when the vehicle is stopped, using the motor as a generator, and charging the battery. It has been. Specifically, immediately after the engine is cold-started, control is performed to increase the target SOC (= target charge capacity) of the battery, and the engine is added with a power generation load to accelerate warm-up (for example, Patent Literature 1).

  At this time, the engine consumes more fuel as much as the power generation load is added, but the power charged by the power generation is used for starting and running in the “motor running mode” after the engine is warmed up. Is possible.

JP 2000-40532 A

However, in the conventional hybrid vehicle control device, the engine warm-up can be accelerated by increasing the target SOC by a certain value, but the fuel consumption before and after the warm-up may deteriorate. There was a problem. Below are two examples.
1. When the initial water temperature is low or the initial SOC is high, the heat energy required to warm up the engine is larger than the electric energy charged in the battery. That is, even if the power generation load operation is performed, the battery SOC is fully charged before the warm-up is completed, and thereafter, no load operation is performed. In general, the fuel efficiency decreases as the load decreases, and in the case of idling with no load, a lot of fuel is consumed just by turning the engine.
2. When the initial water temperature is high or the initial SOC is low, the heat energy required for engine warm-up is smaller than the electric energy charged in the battery. That is, even if the power generation load operation is performed, the warm-up is completed first before the battery SOC is fully charged, so the subsequent load operation is not used for the warm-up, only the heat energy is released from the radiator. , Useless fuel is consumed.

  The present invention has been made paying attention to the above-mentioned problem, and by reducing the difference between the engine warm-up completion timing and the battery charge completion timing at the time of engine cold start, the inefficient fuel consumption is suppressed, and the fuel consumption is improved. An object of the present invention is to provide a hybrid vehicle control device that can be improved.

In order to achieve the above object, in the hybrid vehicle control device of the present invention, the driving source is equipped with a vehicle driving engine and a driving motor driven by charging power to the battery, and when the engine is cold-started, An engine that uses the traveling motor as a generator to cause the traveling motor to generate electric power according to the output of the engine and controls the engine to be warmed up by a load operation that charges the battery while using the engine as a load. A warm-up control means is provided.
In this hybrid vehicle control device, the engine warm-up control means predicts the engine warm-up time and the battery charging time when the engine is cold, and the engine warm-up completion timing and the battery charge completion timing are determined. A set of operating points that fall within a predetermined range is extracted, and load operation is performed at any operating point of the extracted set.

Therefore, in the hybrid vehicle control apparatus of the present invention, when the engine is cold-started, the engine warm-up control means predicts the engine warm-up time and the battery charge time, and the engine warm-up completion timing and battery charge A set of operating points whose completion timing is within a predetermined range is extracted, and load operation is performed at any operating point of the extracted set.
That is, the engine cold start condition is not constant and varies, and for example, by adding a power generation load, charging of the battery is completed before the engine is warmed up or charging of the battery is completed. The engine warm-up is completed before. On the other hand, in the present invention, the engine warm-up completion timing and the battery charging completion timing end within the predetermined range without fail, so that no-load idling operation can be continued or heat energy can be continuously released by load operation. It will be resolved.
As a result, by reducing the difference between the engine warm-up completion timing and the battery charge completion timing at the time of engine cold start, inefficient fuel consumption can be suppressed and fuel consumption can be improved.

1 is an overall system diagram showing an FR hybrid vehicle (an example of a hybrid vehicle) by rear wheel drive to which a control device of Embodiment 1 is applied. 3 is a flowchart showing a flow of engine warm-up control processing executed by the engine controller of the first embodiment. It is an operating point comparison figure which shows the contrast of the engine operating point on the area | region A in the engine warm-up control of Example 1, and the high efficiency operating point on a high efficiency driving line. It is a schematic diagram which shows an example of the battery charge map which wrote the equal charge amount line in the engine warm-up control of Example 1. FIG. FIG. 3 is a schematic diagram illustrating an example of an engine heat generation map in which an equal heat generation amount line is written in the engine warm-up control according to the first embodiment. In the engine warm-up control of the first embodiment, when the equal charge line is changed, the point where the charging ends before the warming-up, the point where the warming-up ends before the charging, and the point where the warming-up and charging end simultaneously It is a battery charge map figure which shows an example showing this tendency. FIG. 6 is an engine heat generation map showing an example of a region A that is a set of operating points at which warm-up and charging end without excess or deficiency in the engine warm-up control according to the first embodiment. In the engine warm-up control according to the first embodiment, an engine showing a state in which a region B in which charging ends first and a region C in which warm-up ends first change depending on each condition of initial engine water temperature, engine heat capacity, initial SOC, and battery capacity. It is a heat_generation | fever map figure. It is a power generation load amount-fuel consumption amount relationship characteristic diagram showing a method of selecting a power generation load amount Pmin that minimizes the amount of fuel consumption from the region A extracted in the engine warm-up control of the first embodiment. FIG. 3 is an engine heat generation map showing a method for determining a final idling operating point at an intersection of a region A and an equal output (Pmin) line in the engine warm-up control according to the first embodiment.

  Hereinafter, the best mode for realizing a control device for a hybrid vehicle of the present invention will be described based on a first embodiment shown in the drawings.

First, the configuration will be described.
FIG. 1 is an overall system diagram showing a rear-wheel drive FR hybrid vehicle (an example of a hybrid vehicle) to which the control device of the first embodiment is applied.

  As shown in FIG. 1, the drive system of the FR hybrid vehicle in the first embodiment includes an engine Eng, a flywheel FW, a motor / generator MG (traveling motor), an automatic transmission AT, a propeller shaft PS, It has a differential DF, a left drive shaft DSL, a right drive shaft DSR, a left rear wheel RL, and a right rear wheel RR. Note that FL is the left front wheel and FR is the right front wheel.

  The engine Eng is a gasoline engine or a diesel engine, and engine start control, engine stop control, and throttle valve opening control are performed based on an engine control command from the engine controller 1. The engine output shaft is provided with a flywheel FW.

  The motor / generator MG is a synchronous motor / generator in which a permanent magnet is embedded in a rotor and a stator coil is wound around a stator, and a three-phase AC generated by an inverter 3 based on a control command from the motor controller 2. It is controlled by applying. The motor / generator MG can operate as an electric motor that is driven to rotate by receiving electric power from the battery 4 (hereinafter, this state is referred to as “powering”), and the rotor is rotated from the engine Eng or the driving wheel. When receiving energy, the battery 4 can be charged by functioning as a generator that generates electromotive force at both ends of the stator coil (hereinafter, this operation state is referred to as “regeneration”). Note that the rotor of the motor / generator MG is connected to the transmission input shaft of the automatic transmission AT via a damper.

  The automatic transmission AT is, for example, a stepped transmission that automatically switches stepped gears according to vehicle speed, accelerator opening, etc., and a stepless gear ratio automatically according to vehicle speed, accelerator opening, etc. It is a continuously variable transmission that switches to. The output shaft of the automatic transmission AT is connected to the left and right rear wheels RL and RR via a propeller shaft PS, a differential DF, a left drive shaft DSL, and a right drive shaft DSR.

  The hybrid drive system of the first embodiment has a “motor travel mode”, an “engine travel mode”, a “motor assist travel mode”, a “travel power generation mode”, a “deceleration regeneration mode”, and the like as travel modes. . “Motor travel mode” travels only with the power of the motor / generator MG. In “engine running mode”, the vehicle runs only with the power of the engine Eng. The “motor-assisted travel mode” travels while assisting the power of the engine Eng by the motor / generator MG. The “running power generation mode” travels while using a part of the power of the engine Eng as the power generation of the motor / generator MG. In the “deceleration regeneration mode”, the vehicle travels at a reduced speed while regenerative power is generated by the motor / generator MG during braking or deceleration.

Next, the control system of the hybrid vehicle will be described.
As shown in FIG. 1, the control system of the FR hybrid vehicle in the first embodiment includes an engine controller 1, a motor controller 2, an inverter 3, a battery 4, a battery controller 5, an AT controller 7, and a brake controller 9. And an integrated controller 10. The engine controller 1, the motor controller 2, the battery controller 5, the AT controller 7, the brake controller 9, and the integrated controller 10 are connected via a CAN communication line 11 that can mutually exchange information. .

  The engine controller 1 includes engine speed information from the engine speed sensor 12, engine water temperature information from the engine water temperature sensor 23 (engine water temperature detecting means), and outside air temperature from the outside air temperature sensor 24 (outside air temperature detecting means). Enter information. Then, battery SOC information, battery voltage information, target engine torque command, and the like are input from the integrated controller 10. Then, a command for controlling the engine operating point (Ne, Te) is output to the throttle valve actuator or the like of the engine Eng. The battery SOC information and the battery voltage information are supplied to the integrated controller 10 from the battery controller 5 (battery charge capacity detection means, battery voltage detection means) that monitors the battery SOC and battery voltage.

  The motor controller 2 inputs information from the resolver 13 that detects the rotor rotational position of the motor / generator MG, a target MG torque command and a target MG rotational speed command from the integrated controller 10, and other necessary information. Then, a command for controlling the motor operating point (Nm, Tm) of the motor / generator MG is output to the inverter 3.

  The AT controller 7 inputs information from an accelerator opening sensor 16, a vehicle speed sensor 17, and other sensors 18 (transmission input rotation speed sensor, inhibitor switch, etc.). Then, when driving with the D range selected, a control command for obtaining the searched gear position is searched for the optimum gear position based on the position where the operating point determined by the accelerator opening APO and the vehicle speed VSP exists on the shift map. Output to AT hydraulic control valve unit CVU. When a shift control command such as a shift prohibition command is input from the integrated controller 10 in addition to the automatic shift control, the shift control based on the instruction from the integrated controller 10 is performed in preference to the normal shift control using the shift map. Is called.

  The brake controller 9 inputs a wheel speed sensor 19 for detecting the wheel speeds of the four wheels, sensor information from the brake stroke sensor 20, a regenerative cooperative control command from the integrated controller 10, and other necessary information. And, for example, at the time of brake depression, if the regenerative braking force is insufficient with respect to the required braking force required from the brake stroke BS, the shortage is compensated with mechanical braking force (hydraulic braking force or motor braking force) Regenerative cooperative brake control is performed.

  The integrated controller 10 manages the energy consumption of the entire vehicle and has a function for running the vehicle with the highest efficiency. The motor rotation speed sensor 21 for detecting the motor rotation speed Nm and other sensors and switches 22 Necessary information and information via the CAN communication line 11 are input. Then, the target engine torque command to the engine controller 1, the target MG torque command and the target MG rotational speed command to the motor controller 2, the charge / discharge command to the battery controller 5, the shift control command to the AT controller 7, and the regenerative cooperative control to the brake controller 9 Outputs a command. In addition, on the indicator 26 set on the instrument panel or the like in the passenger compartment, during the warm-up operation of the engine Eng, it is displayed that the engine is warming up, and the scheduled warm-up end time is displayed.

  FIG. 2 is a flowchart showing a flow of engine warm-up control processing executed by the engine controller 1 of the first embodiment (engine warm-up control means). Hereinafter, each step of FIG. 2 will be described.

  In step S1, the current engine water temperature is read from the engine water temperature sensor 23, and the process proceeds to step S2.

  In step S2, following the reading of the engine water temperature in step S1, the current engine water temperature is subtracted from the engine water temperature at which the warm-up is completed, thereby calculating the engine water temperature increase required for engine warm-up. Proceed to

  In step S3, following the calculation of the required engine water temperature rise amount in step S2, the heat energy required for engine warm-up is calculated by multiplying the required engine water temperature rise amount by the engine Eng heat capacity, and to step S4 move on.

  In step S4, following the calculation of the heat energy required for engine warm-up in step S3, the current battery SOC is read, and the process proceeds to step S5.

  In step S5, following the reading of the current battery SOC in step S4, the current battery SOC is calculated by subtracting the current battery SOC from the battery SOC at the battery charge limit, and the process proceeds to step S6.

  In step S6, following the calculation of the required battery SOC increase in step S5, the current battery voltage is read, and the process proceeds to step S7.

  In step S7, following the reading of the current battery voltage in step S6, the battery voltage and the battery SOC are multiplied by the required battery SOC increase amount to calculate the electric energy required for charging, and the process proceeds to step S8.

  In step S8, following the calculation of the electric energy required for charging in step S7, the outside air temperature from the outside air temperature sensor 27 is read, and the process proceeds to step S9.

  In step S9, following reading of the outside air temperature in step S8, an engine heat generation map (see FIG. 5) of a preset engine heat generation amount is read, and the process proceeds to step S10. As shown in FIG. 5, the engine heat generation map has the engine speed on the horizontal axis and the engine torque on the vertical axis. If the engine operating point (rotation speed, torque) is determined, The calorific value is referred to.

In step S10, following the reading of the engine heat generation map in step S9, by subtracting heat loss from the engine heat generation map of the engine heat generation amount, a substantial engine heat generation engine heat generation map is created and updated, Proceed to step S11.
Here, the heat loss is calculated by subtracting the outside air temperature from the temperature of the engine Eng and multiplying by a preset coefficient. The temperature of the engine Eng is represented by the average value of the initial engine water temperature in step S1 and the water temperature at the end of warm-up.

In step S11, following the creation of the engine heat generation map in step S10, a preset engine output map of engine output is read, and the process proceeds to step S12.
In this engine output map, the engine speed is taken on the horizontal axis and the engine torque is taken on the vertical axis. When the engine Eng operating point (rotation speed, torque) is determined, the engine output, that is, the work per hour is Referenced.

In step S12, following the reading of the engine output map in step S11, the electric loss during charging is calculated, and the process proceeds to step S13.
That is, the electric loss during charging is calculated by calculating the motor loss from the motor loss map of the motor / generator MG and taking the sum of the motor loss and the battery 4 loss. Here, the loss of the battery 4 is calculated from the resistance read from the resistance map of the battery 4 multiplied by the square of the current.

  In step S13, following the calculation of the electric loss during charging in step S12, the electric charge during charging is subtracted from the output of the engine Eng. Reference) is created, and the process proceeds to step S14.

In step S14, following the creation of the battery charge map in step S13, the warm-up time and the charge time are calculated at each operating point, and the process proceeds to step S15.
By calculating the warm-up time and the charge time at each operating point, it is possible to extract a region B where charging ends first and a region C where warm-up ends first (see FIG. 8).

In step S15, following the calculation of the warm-up time and the charge time at each operating point in step S14, the part that becomes the boundary between region B where charging ends first and region C where warm-up ends first is extracted as region A Then, the process proceeds to step S16.
That is, a set of operating points at which the engine warm-up completion timing and the battery charging completion timing are within a predetermined range are extracted as the region A.

  In step S16, following the extraction of the area A in step S15, based on the warm-up end time calculated in step S14, the display 26 indicates that the warm-up operation is being performed and the warm-up is scheduled to end. A command to display the time is output, and the process proceeds to step S17.

In step S17, following the display of the scheduled warm-up end time in step S16, the fuel flow rate per unit time is read at each operating point in region A, and the process proceeds to step S18.
Here, the fuel flow rate per unit time is read from a fuel flow rate map (fuel injection amount map) at each operating point used for fuel injection control of the engine Eng.

In step S18, following the reading of the fuel flow rate per unit time in step S17, the amount of fuel consumed by the end of warm-up at each operating point in region A is calculated, and the process proceeds to step S19.
The amount of fuel consumed by the end of warm-up is calculated by multiplying the fuel flow rate (step S17) by the engine warm-up time (step S14).

  In step S19, following the calculation of the amount of fuel consumed by the end of warm-up in step S18, the operating point with the smallest amount of fuel consumed by the end of warm-up is extracted at each operating point in region A, Proceed to step S20.

  In step S20, following the selection of the operating point with the minimum fuel consumption in step S19, the load operation is performed at the operating point with the selected minimum fuel consumption, and the process proceeds to step S21.

  In step S21, following the load operation at the selected operating point in step S20, it is determined whether the engine water temperature is higher or lower than the warm-up end water temperature, and if YES (engine water temperature <warm-up end water temperature), Since it is necessary to continue the machine operation, the process returns to step S1, and if NO (engine water temperature ≧ warm-up water temperature), the warm-up is terminated, and the process proceeds to step S22.

In step S22, following the determination in step S21 that the engine water temperature is equal to or higher than the warm-up end water temperature, a warm-up end signal is sent to the integrated controller 10 and the process proceeds to the end.
When the integrated controller 10 receives this warm-up end signal, the FR hybrid vehicle can perform idling stop control when the signal is stopped or in a low-load travel area.

Next, the operation will be described.
In the first embodiment, as an example, it is assumed that after starting the engine from a low temperature state, the engine warm-up is completed, the indoor heater is effective, and the window is cleared until the window is cleared. The driver waits until such a state is reached, and then the fuel consumed before the completion of warm-up to start running and the amount of electric power charged by the power generation load affect the overall fuel consumption. Hereinafter, the effects of the control apparatus for the FR hybrid vehicle of the first embodiment are “engine warm-up control action”, “fuel efficiency improvement action during engine warm-up”, and “minimization action of fuel consumption until engine warm-up is completed”. The explanation will be divided into “notification of the warm-up operation and the scheduled warm-up end time”.

[Engine warm-up control action]
After starting the engine Eng in the low temperature state, the engine warm-up control is started when the engine water temperature <the warm-up end water temperature. In the flowchart of FIG. 2, step S1, step S2, step S3, step S4, step S5, Step S6 → Step S7 → Step S8 → Step S9 → Step S10 → Step S11 → Step S12 → Step S13 → Step S14 → Step S15 → Step S16 → Step S17 → Step S18 → Step S19 → Step S20 → Step S21 . Regardless of the load operation at the selected operating point in step S20, the flow from step S1 to step S21 is repeated as long as the engine water temperature <the warm-up end water temperature.

  Then, when the engine water temperature is equal to or higher than the warm-up end water temperature by the load operation at the selected operating point in step S20, the process proceeds from step S21 to step S22 → end, and a warm-up end signal is sent to the integrated controller 10 to The engine warm-up control is terminated after the idling stop control can be performed when the vehicle is stopped.

  Therefore, after the engine warm-up control is finished, there is no problem in combustion stability or exhaust performance even when idling stop control is performed when the signal is stopped or in a low-load traveling region. In particular, when the “motor running mode” is provided as in the FR hybrid vehicle of the first embodiment, the engine Eng that is not efficient is stopped not only when the signal is stopped but also in the low load running area, and the “motor running mode” is set. By running, fuel consumption can be improved. Furthermore, the electric power charged in the battery 4 by the power generation in the engine warm-up control can be used for starting and running in the “motor running mode” after warm-up.

[Improves fuel economy when the engine is warmed up]
In the first embodiment, at the time of cold start, the engine warm-up time and the battery charge time are predicted, and a set of operating points at which the engine warm-up completion timing and the battery charge completion timing are within a predetermined range (see region A in FIG. 3). Is extracted (steps S1 to S15). The load operation is performed at any operating point of this set until the warm-up is completed. In the first embodiment, as shown in FIG. 1, a vehicle including a hybrid system in which an engine Eng and a motor / generator MG are coaxially coupled is assumed.

  Therefore, even if conditions such as the initial engine water temperature, initial battery SOC, and outside air temperature change, the engine warm-up and battery charging will be completed without excess or deficiency, so the inefficient fuel consumption that was the problem of the conventional example will be reduced. Can be suppressed. Hereinafter, the details of the fuel efficiency improvement effect at the time of engine warm-up in Example 1 will be described.

  First, a set of operating points where the engine warm-up completion timing and the battery charge completion timing are within a predetermined range is defined as region A (see FIG. 3). As shown in FIG. 3, the operating point in the region A has a shape different from that of the high-efficiency operation line. The reason why the region A is focused will be described below.

  Normally, in order to efficiently obtain electric power generated by the engine, it is better to operate at an operating point that is above the high-efficiency operating line even when charging losses are taken into account (see the high-efficiency operating point in FIG. 3). ). However, since the battery capacity is limited, if the engine is operated on such a high-efficiency operating point, the battery is fully charged before the engine warm-up is completed. For this reason, after that, idling operation with low efficiency will be performed.

Therefore, a set of operating points (see region A in FIG. 3) at which engine warm-up and battery charging end without excess or deficiency is extracted, and operation is performed at operating points on the battery limit line. This region is a set of operating points at which energy efficiency is maximized under the limitation that the battery capacity is finite.
For this reason, if the region A is defined by the vehicle system of the first embodiment (engine Eng, motor / generator MG, battery 4, etc.), warm-up operation with high energy efficiency can be performed.

  However, since the region A changes depending not only on the vehicle system but also on conditions such as the initial engine water temperature, the initial battery SOC, and the outside air temperature, it is necessary to always perform calculation on the vehicle and extract the region A. Therefore, a method for extracting the region A will be described below.

  FIG. 4 shows a battery charge map in which a general motor equal charge amount line is shown on the engine operating point, and FIG. 5 shows an engine heat generation in which an engine equal heat amount line is shown on the engine operating point. A map is shown (horizontal axis: engine speed, vertical axis: engine torque). Here, the equal charge amount line is obtained by subtracting the loss during charging from the equal output line, but is essentially the same as the distribution of the equal output line. On the other hand, the calorific value indicated by the isothermic calorific value line tends to increase as the output increases and the rotation speed increases.

  When the battery charge amount is large, the battery charge time is shortened, and when the engine heat generation amount is large, the engine warm-up time is shortened. Since the area A is a set of operating points at which the battery charging time and the engine warm-up time are substantially equal, the area A is calculated from the relationship between the battery charging amount and the engine heat generation amount.

  This relationship is shown in FIGS. In FIG. 6, the isothermal line and the equal charge line are illustrated so as to overlap each other. For example, when attention is paid to the equal charge line (a), the load is applied at an arbitrary operating point on the equal charge line (a). When driving, the time required to complete charging is the same. On the other hand, the low rotation speed side of these operating points has a small calorific value, so the time required for engine warm-up is long, and charging ends before warm-up (for example, Δ (a) -1 point). On the contrary, since the heat generation amount on the high rotation side is large, the time required for engine warm-up is short, and warm-up is completed before charging (for example, ▲ (a) -3 points). In other words, there is an operating point between the △ (a) -1 and ▲ (a) -3 on the equal charging line (a) that always ends warm-up and charging. Is ● (a) -2.

  Similarly, on other lines such as the equal charge line (b) and equal charge line (c), the point indicated by △ where charging ends prior to warm-up, and conversely before charging. You can find the point marked with ▲ when the warm-up ends. From this, it is possible to extract a region A, which is a set of operating points at which warm-up and charging end without excess or deficiency by tying up ● while changing the power of the equal charge line.

  As described above, the charging time is the same on the equal charging line, but there is an operating point somewhere on the line where the warm-up time and charging time are the same. Region A is determined from the set of operating points. A region A extracted by this extraction method is shown in FIG.

  Since the area A thus extracted changes depending on the conditions, the tendency of the warm-up / charge area is collectively shown in FIG.

  Here, at the operating point of a higher load than the region A, the battery charging is finished earlier than the engine warm-up, and this is defined as a region B. Further, at an operating point with a lower load than the region A, the engine warm-up ends before the battery charging. This is defined as a region C.

  In the region B, as shown on the upward arrow side in FIG. 8, the amount of heat necessary for engine warm-up is large, that is, the initial engine water temperature is low, the engine heat capacity is large, the initial battery SOC is large, and the battery capacity is small. The area occupying area increases depending on such conditions.

  Further, in the region C, as shown on the downward arrow side in FIG. 8, the condition that the power required for battery charging is large, that is, the initial battery SOC is small, the battery capacity is large, the initial engine water temperature is high, the engine heat capacity is high. The area occupied area increases depending on the condition such as small.

  As described above, in the first embodiment, the region A that is a set of operating points that maximizes the energy efficiency in consideration of the battery capacity can be extracted even under different conditions and can be charged with energy efficiency. It is possible to improve fuel efficiency from the viewpoint including the above.

[Minimization of fuel consumption until engine warm-up is completed]
In the first embodiment, an operating point that minimizes the amount of fuel consumed before warming up is selected from operating points in the region A. The idling operation is performed at this operating point until the warm-up is completed (steps S17 to S21).

  Therefore, engine warm-up and battery charging can be completed without excess or deficiency while achieving minimization of fuel consumption. Hereinafter, the details of the effect of minimizing the fuel consumption until the end of engine warm-up in the first embodiment will be described.

  First, in the set of operating points in the region A, the battery 4 is fully charged when the engine warm-up is completed, regardless of which operating point is selected. Since the charge amount at the time of full charge is set to a certain value, the charge energy obtained after engine warm-up is the same, so simply compare the estimated fuel consumption that will be consumed by the end of warm-up. It is possible to determine the superiority or inferiority of fuel consumption.

Therefore, the power generation load amount and the fuel consumption amount at each operating point are calculated and compared (see FIG. 9).
The power generation load amount in FIG. 9 is a work amount per unit time calculated by engine torque × engine speed at each operating point. The fuel consumption amount in FIG. 9 is calculated by fuel flow rate at the operating point × warm-up time, and the warm-up time is calculated by engine warm-up required heat energy / engine heat generation amount. In this calculation process, the power generation load Pmin that minimizes the fuel consumption is selected.

  Here, it is conceivable that the power generation load Pmin changes depending on conditions. For example, in a low temperature state, the heat loss increases and the substantial engine heat generation amount decreases, so that the warm-up time increases. Therefore, in such a state, it is necessary to secure an engine heat generation amount that is commensurate with heat loss, and as a result, the power generation load amount Pmin may be shifted to a high load side. In the first embodiment, as shown in the optimum point B → optimal point A in FIG. 9, the optimum load that changes according to the heat generation condition so that the power generation load Pmin is shifted to the higher load side as the temperature is lowered from the normal temperature. By selecting Pmin, it is possible to minimize the amount of fuel consumed by the end of warm-up. As shown in FIG. 10, the final engine operating point is determined by the intersection of the region A and the equal output (Pmin) line, and the power generation load operation is performed at this operating point until the warm-up is completed.

[Notification of warm-up operation and scheduled warm-up end time]
In the first embodiment, the indicator 26 (in-vehicle instrument, monitor, etc.) set at a position that can be visually recognized by the passenger is used to notify the passenger that the engine is warming up, and the scheduled warm-up end time is displayed. (Step S16).

  For example, when the outside air temperature is extremely low, or when the outside air temperature is high, an operating point with severe sound vibration may be selected. When idling is performed at such an operating point, there is a problem that distrust is given to the occupant. Therefore, by notifying the occupant that the warm-up operation is in progress, it is possible to avoid a situation in which the occupant feels distrust even when the idling operation is performed at an operating point with severe sound vibration.

  In addition, the first embodiment assumes a scene in which the vehicle starts running after waiting until the warm-up ends. Therefore, starting the run immediately after the end of warm-up can be most effective in terms of energy. Accordingly, by notifying the occupant of the warm-up end time using the warm-up end time predicted during engine warm-up control, the charging power of the battery 4 is discharged and the motor / generator MG is discharged during the travel from the start after the warm-up. Will be informed that the “motor running mode” for driving is highly available. Therefore, when the driver travels while recognizing the “motor travel mode”, the travel distance traveled by stopping the operation of the engine Eng is extended, and the fuel consumption reduction effect can be maximized.

Next, the effect will be described.
In the control device for the FR hybrid vehicle of the first embodiment, the effects listed below can be obtained.

(1) The engine Eng for driving the vehicle and the motor for driving (motor / generator MG) driven by the charging power to the battery 4 are installed in the drive source, and when the engine Eng starts cold, the engine warms up by load operation. In the control device for a hybrid vehicle (FR hybrid vehicle) provided with engine warm-up control means for performing control for prompting the engine, the engine warm-up control means (FIG. 2) is configured so that the engine Eng Predicting the warm-up time and the charging time of the battery 4, extracting a set of operating points where the engine warm-up completion timing and the battery charging completion timing are within a predetermined range, and load operation at any operating point of the extracted set I do.
For this reason, when the engine Eng is cold-started, by reducing the difference between the engine warm-up completion timing and the battery charge completion timing, it is possible to suppress inefficient fuel consumption and improve fuel efficiency.

(2) An engine water temperature detecting means (engine water temperature sensor 23) for detecting the cooling water temperature of the engine Eng and an outside air temperature detecting means (outside air temperature sensor 24) for detecting the outside air temperature are provided, and the engine warm-up control means (FIG. 2) calculates the engine warm-up required thermal energy based on the engine water temperature detection value (step S3), creates an engine heat generation map based on the outside air temperature detection value and the engine heat generation map (step S10), The engine Eng warm-up time prediction based on the required warm-up heat energy and the engine heat generation map is repeated until it is determined that the warm-up has been completed (step S14).
For this reason, during the engine warm-up control, the engine Eng warm-up time can be accurately predicted regardless of changes in the conditions of the engine water temperature and the outside air temperature.

(3) Battery charge capacity detection means (battery controller 5) for detecting the charge capacity of the battery 4 and battery voltage detection means (battery controller 5) for detecting the voltage of the battery 4 are provided, and the engine warm-up is provided. The control means (FIG. 2) calculates the electric energy required for charging based on the detected battery charge capacity value and the detected battery voltage value (step S7), and creates a charging map based on the charging loss and the engine output map (step S13). The charging time prediction of the battery 4 based on the electric energy required for charging and the charging map is repeated until it is determined that the warm-up is finished (step S14).
For this reason, during the engine warm-up control, the charging time of the battery 4 can be accurately predicted regardless of changes in the battery charge capacity (battery SOC) and battery voltage conditions.

(4) The engine warm-up control means (FIG. 2) includes a second region (region B) in which charging ends first and a third in which warm-up ends according to the predicted engine warm-up time and battery charging time. First, a region (region C) is extracted, and an operating point at which the engine warm-up completion timing and the battery charge completion timing are within a predetermined range is gathered at a portion that is a boundary between the two extracted regions (regions B and C). Extracted as a region (region A) (step S15).
For this reason, when the warm-up and charging end timings at different operating points are determined while changing the power of the equal charging line, the first region (region A), the second region (region B), and the third region (region C). The first region (region A) where the operation points at which the engine warm-up completion timing and the battery charge completion timing are within a predetermined range are collected while performing extraction processing with fewer operation point checks. Can be extracted with high accuracy.

(5) The engine warm-up control means (FIG. 2) calculates the amount of fuel consumed until the end of warm-up based on the fuel flow rate per unit time at each operating point where engine warm-up and battery charging end without excess or deficiency. (Step S18), among the operating points for which the fuel consumption is calculated, select the operating point with the minimum fuel consumption (Step S19), and perform load operation at the selected operating point until the warm-up is completed (Step S19). S20).
For this reason, at the time of engine warm-up control, engine warm-up and battery charging can be completed without excess or shortage while minimizing fuel consumption.

(6) The engine warm-up control means (FIG. 2) informs the occupant that the engine is warming up during engine warm-up control (step S16).
For this reason, for example, even when idling is performed at an operating point where sound vibration is severe, it is possible to avoid a situation in which distrust is felt to the occupant.

(7) During the engine warm-up control, the engine warm-up control means (FIG. 2) sets the estimated warm-up end time to a position where a passenger in the vehicle can visually recognize the warm-up end time based on the predicted engine Eng warm-up end time. Display (step S16).
For this reason, the distance traveled by stopping the operation of the engine Eng is extended, and the fuel consumption reduction effect can be maximized.

  As mentioned above, although the control apparatus of the hybrid vehicle of this invention was demonstrated based on Example 1, it is not restricted to this Example 1 about a concrete structure, The invention which concerns on each claim of a claim Design changes and additions are permitted without departing from the gist of the present invention.

  In the first embodiment, during the engine warm-up control, the warm-up operation and the scheduled warm-up end time are displayed on the display 26. However, it may be used in combination with visual notification by an instrument, a monitor, or the like, as well as auditory notification by a notification sound, tactile notification by steering wheel vibration, or the like.

  In the first embodiment, an example in which the engine heat generation map and the charge map are always created and the region A is extracted following the change in conditions at the time of cold start is shown. However, an example of extracting a region A that meets the conditions while simplifying the calculation process using a region map preset according to initial conditions at the time of cold start or a region map preset according to a change in conditions at the time of cold start. It is also good.

  In the first embodiment, an application example to a motor assist type FR hybrid vehicle in which an engine and a motor are coaxially coupled is shown. However, an FR hybrid vehicle in which a clutch is interposed between the engine and the motor, or another type of FF Or it can apply also to FR hybrid vehicle. In short, the present invention can be applied to any hybrid vehicle in which the driving source is equipped with a vehicle driving engine and a driving motor driven by charging power to the battery.

Eng engine
MG motor / generator (travel motor)
AT automatic transmission
RL left rear wheel
RR Right rear wheel 1 Engine controller 2 Motor controller 3 Inverter 4 Battery 5 Battery controller (battery charge capacity detection means, battery voltage detection means)
7 AT controller 9 Brake controller 10 Integrated controller 23 Engine water temperature sensor (engine water temperature detection means)
24 Outside air temperature sensor (outside air temperature detecting means)
26 Display

Claims (7)

The driving source is equipped with an engine for driving the vehicle and a driving motor driven by charging power to the battery,
When the engine starts cold, the traveling motor is used as a generator, and the traveling motor is caused to generate electric power by the output of the engine to load the engine and load the battery to load the engine. In a hybrid vehicle control device provided with engine warm-up control means for performing control for prompting the machine,
The engine warm-up control means predicts the engine warm-up time and the battery charging time when the engine is cold, and sets the operating point at which the engine warm-up completion timing and the battery charge completion timing are within a predetermined range. A control apparatus for a hybrid vehicle, wherein a set is extracted, and a load operation is performed at any operating point of the extracted set. In the hybrid vehicle control device according to claim 1,
Engine water temperature detecting means for detecting the cooling water temperature of the engine;
An outside air temperature detecting means for detecting the outside air temperature,
Wherein the engine warm-up control means calculates the engine warm-up required heat energy based on the engine coolant temperature detection value, based on an engine heating map of the engine heating value which is previously set based on the outside air temperature detection value and the engine operation point An engine heat generation map of the engine heat generation amount obtained by subtracting heat loss from the engine heat generation map is generated, and the engine warm-up time prediction based on the engine warm-up required heat energy and the engine heat generation map is determined to be the end of warm-up. A hybrid vehicle control device that is repeatedly performed until In the hybrid vehicle control device according to claim 1 or 2,
Battery charge capacity detection means for detecting the charge capacity of the battery;
Battery voltage detecting means for detecting the voltage of the battery; and
The engine warm-up control means calculates a required charging electric energy based on a battery charging capacity detection value and a battery voltage detection value, creates a charging map based on a charging loss and an engine output map, and The hybrid vehicle control device, wherein the battery charging time prediction based on the charging map is repeatedly performed until it is determined that the warm-up is completed. In the control apparatus of the hybrid vehicle described in any one of Claim 1- Claim 3,
The engine warm-up control means extracts a second region where charging ends first and a third region where warm-up ends first according to the predicted engine warm-up time and battery charging time, The hybrid vehicle control device is characterized in that the boundary portion is extracted as a first region where operating points at which the engine warm-up completion timing and the battery charge completion timing are within a predetermined range are gathered. In the hybrid vehicle control device according to any one of claims 1 to 4,
The engine warm-up control means calculates the amount of fuel consumed until the end of warm-up based on the fuel flow rate per unit time at each operating point where engine warm-up and battery charging end without excess or deficiency. A control apparatus for a hybrid vehicle, wherein an operating point with the minimum amount of fuel consumption is selected from each operating point and load operation is performed at the selected operating point until the warm-up is completed. In the control apparatus of the hybrid vehicle described in any one of Claim 1- Claim 5,
The engine warm-up control means informs the occupant that the engine is warming up during engine warm-up control. In the hybrid vehicle control device according to claim 6,
The engine warm-up control means displays a scheduled warm-up end time at a position where a passenger in the vehicle can visually recognize based on the predicted warm-up end time of the engine during engine warm-up control. Vehicle control device.

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