JP2005192319A - Controller of hybrid vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller of a hybrid vehicle capable of enhancing fuel consumption. <P>SOLUTION: In a controller of a hybrid vehicle, a navigation system specifies a scheduled traveling course of the vehicle (S101), and a vehicle controller estimates the traveling vehicle speed on that scheduled traveling course as a vehicle speed pattern (S103) and then divides the scheduled traveling course from start to stop in the vehicle speed pattern into a plurality of traveling sections (S105). The vehicle controller estimates the time required for traveling each traveling section (S107), sets an operation plan for traveling such a traveling section as the traveling time falls within an optimal time TX entirely in motor drive mode (S111), and performs the drive control of the vehicle according to that operation plan (S113). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a control device for a hybrid vehicle that uses an internal combustion engine and an electric motor as driving force sources.

  In a hybrid vehicle that uses an engine (internal combustion engine) and a motor (electric motor) as driving force sources, the motor is used as a driving force source when starting, and when the vehicle speed increases to some extent, the motor is stopped and the engine is switched to the driving force source. Or, switch to hybrid drive using both engine and motor. This is because the efficiency of the output torque with respect to the fuel consumption of the engine (hereinafter referred to as “engine efficiency”) is low in the low engine speed range including when the vehicle is starting.

  On the other hand, in the rotation region where the engine efficiency is good, the torque that exceeds the torque output necessary for driving is output, the generator is operated with the surplus torque, and the generated power is charged to the battery that supplies power to the motor. To do. As described above, a hybrid vehicle generally uses a technique of driving with a motor in a region where the engine efficiency is low and supplementing electric power for driving the motor in a region where the engine efficiency is high. The battery is also charged by regenerative power generated during braking.

  Here, the vehicle speed pattern of the route on which the hybrid vehicle is scheduled to travel (hereinafter referred to as the “scheduled route”) is estimated in advance (the predicted value of the vehicle speed at each point on the route is linked to the entire route). If possible, the distribution of the driving force source by the motor and the driving force source by the engine (hereinafter referred to as “driving force source distribution”) can be made more efficient based on the vehicle speed pattern.

Therefore, as a method for predicting a vehicle speed pattern, for example, a “drive control device for a hybrid vehicle” disclosed in Patent Document 1 below has been proposed. In this disclosed technology, “the route to the destination at the point where the start and stop are predicted is divided into a plurality of sections, and for each section based on the road condition of the route to the destination and the driving history of the driver. Estimate the vehicle speed pattern, and based on the vehicle speed pattern and the fuel consumption characteristics of the engine, set the engine and motor operation schedule for each section so that the fuel consumption to the destination is minimized. Reference 1; paragraph number 0007). Further, as a method for selecting a travel section by a motor, “a section in which the engine is operated at an operation point with the lowest efficiency is selected as a travel section by a motor” (Patent Document 1; paragraph 0040).
JP 2000-333305 A (2nd to 8th pages, FIGS. 1 to 10)

  However, in the “drive control device for a hybrid vehicle” disclosed in Patent Document 1, “in general, the lower the engine speed, the lower the efficiency. (Omitted). An example of a charging / discharging schedule is shown, such as `` Running the motor with a motor and pre-generating electric energy consumed by the motor in this section in the traveling section with a 50 km / h engine and storing it in the main battery ''. (Patent Document 1; Paragraph 0020), the vehicle speed always changes in general traveling. For this reason, when the control of the driving force source distribution depending on the vehicle speed is performed, for example, when a route section that travels at a low vehicle speed is motor-driven and the other is an engine or a hybrid drive of an engine and a motor, Not only frequent switching of drive stop occurs, but also engine start / stop frequently occurs.

  That is, in the control of the driving force source distribution depending on the vehicle speed, the vehicle speed is constantly changing, and the engine efficiency is reduced when the engine is started. Therefore, the engine is frequently stopped and started due to fluctuations in the vehicle speed. Such control results in a reduction in fuel consumption efficiency. Furthermore, the engine speed changes separately from the change in vehicle speed. For example, even if the vehicle speed is constant, when the accelerator is turned off, the engine speed decreases to near the idling region. Therefore, if the engine is stopped when the engine speed is reduced, the fuel consumption efficiency is reduced as described above when the engine is started next time. As described above, the conventional technique in which the driving force source distribution is controlled depending on the vehicle speed or the engine rotational speed has a problem that the fuel consumption is not necessarily suppressed.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control device for a hybrid vehicle that can improve the fuel efficiency of the hybrid vehicle.

  In order to achieve the above object, the hybrid vehicle control device according to claim 1, which is described in the claims, is a hybrid vehicle control device using an internal combustion engine and an electric motor as a driving force source, and the hybrid vehicle travels. A plurality of planned travel routes, with a planned travel route identifying means for identifying a planned route, vehicle speed pattern estimating means for estimating a vehicle speed traveling on the planned travel route as a vehicle speed pattern, and starting and stopping in the vehicle speed pattern as one segment. A planned travel route dividing means for dividing the travel section, travel time estimation means for estimating the travel time required for traveling in the travel section for each travel section, and a travel section in which the travel time is within a predetermined time. An operation plan setting means for setting an operation plan for running by the driving force source of the electric motor; And drive control means for controlling the driving of Brides vehicle, in that it comprises the technical features.

  Further, in the hybrid vehicle control device according to claim 2, the predetermined time is defined as “the driving force of the internal combustion engine is defined as a travel section in which the travel time is within the predetermined time”. The amount of power consumed when the vehicle is driven by the power source and the amount of power consumed when the vehicle is driven by the driving force source of the motor in the travel section within the predetermined time. Alternatively, it is a technical feature that it is a time when the difference from the “fuel consumption for power generation consumed when supplemented by power generation by regenerative braking” is maximized. Here, “power generation by regenerative braking” refers to power generation using deceleration energy during braking (the same applies hereinafter).

  Furthermore, in the hybrid vehicle control device according to claim 3, when the vehicle travels in the travel section having the travel time that is less than a predetermined threshold value by the drive power source of the internal combustion engine in claim 1. A fuel consumption amount estimating means for estimating the amount of fuel consumed for traveling, and a power consumption amount consumed when traveling by a driving force source of the electric motor in a travel section having the travel time less than the predetermined threshold. Power consumption estimation means for estimating the power consumption, and for power generation consumed when the power consumption is compensated by power generation by the internal combustion engine or power generation by regenerative braking within the travel section where the travel time is equal to or greater than the predetermined threshold Fuel consumption estimation means for estimating fuel consumption, and a fuel consumption consumption calculation for calculating a fuel consumption consumption as a difference between the fuel consumption for traveling and the fuel consumption for power generation Means, a threshold value changing means for increasing or decreasing the predetermined threshold by a predetermined amount after calculating the saved fuel consumption, the traveling fuel consumption estimating means, the power consumption estimating means, a fuel consumption Predetermined time setting means for repeatedly executing the estimation means, the saved fuel consumption amount calculating means, and the threshold value changing means, and setting the predetermined threshold value at which the saved fuel consumption amount reaches a maximum value as the predetermined time. Is a technical feature.

  Furthermore, in the hybrid vehicle control device according to claim 4 described in the claims, in claim 2 or 3, the fuel consumption for power generation is at a maximum efficiency point according to engine characteristics of the internal combustion engine. It is a technical feature.

  Moreover, in the hybrid vehicle control device according to claim 5, wherein the driving plan setting unit according to any one of claims 2 to 4, the travel time exceeds the predetermined time. Technically, a plan is made such that, among the travel sections, a section having a long travel section is preferentially selected over a shorter section, and the power consumption is compensated in the selected travel section. Features.

  In the first aspect of the invention, the planned travel route of the hybrid vehicle is specified by the planned travel route specifying means, the vehicle speed traveling on the planned travel route is estimated as the vehicle speed pattern by the vehicle speed pattern estimating means, and the planned travel route dividing means is used. The planned travel route is divided into a plurality of travel sections, with the vehicle speed pattern from start to stop as one break. Then, the travel time required for traveling in this travel section is estimated for each travel section by the travel time estimating means, and for the travel section where the travel time is within a predetermined time, all of the travel section is driven by the driving force of the motor. An operation plan for traveling by the power source is set by the operation plan setting means, and the drive control of the hybrid vehicle is performed by the drive control means according to the operation plan. As a result, an operation plan is set for driving the entire driving section with the driving force source of the electric motor for the driving time required for driving the driving section within a predetermined time, and the hybrid vehicle drive control is performed accordingly. Therefore, in the travel section that can travel within a predetermined time, all of the travel section is traveled by the driving force source of the electric motor.

  That is, according to the first aspect of the present invention, focusing on the time from the start to the stop (the travel time within the travel section) without depending only on the vehicle speed and the rotational speed of the internal combustion engine, the travel time is within a predetermined time. In some cases, drive control using the electric motor as the driving force source is performed in the entire travel section. Therefore, since the drive control by the internal combustion engine is not performed in the travel section in which the travel time estimated in this way is within a predetermined time, the drive force between the electric motor and the internal combustion engine is not performed in the travel section. Source switching does not occur. Therefore, since the start and stop of the internal combustion engine is not repeated, an increase in fuel consumption due to the start of the internal combustion engine can be suppressed, and the fuel efficiency of the hybrid vehicle can be improved.

  In the invention of claim 2, the predetermined time is “the amount of fuel consumed for traveling that is consumed when the entire driving section within the predetermined time is traveled by the driving force source of the internal combustion engine” and “the predetermined time”. Fuel consumption for power generation that is consumed when the power consumption that is consumed when traveling within the traveling section within the time by the driving power source of the motor is compensated by power generation by the internal combustion engine or power generation by regenerative braking "Is the time when the difference from

  That is, the predetermined time, which is a criterion for determining whether or not to travel all within the travel section with the driving force source of the electric motor, is the fuel consumption for traveling when the internal combustion engine is used as the driving power source and the electric motor as the driving power source. The difference from the fuel consumption for power generation when the power consumption consumed at the time is compensated, that is, the time when the fuel consumption that can be saved when the electric motor is used as the driving power source is maximized. Thereby, the operation plan setting means (claim 1) can set an operation plan as to whether or not the entire driving section is driven by the driving force source of the electric motor based on such time. Therefore, an increase in fuel consumption due to the start of the internal combustion engine can be efficiently suppressed, and the fuel efficiency of the hybrid vehicle can be improved more reliably.

  In the invention of claim 3, the travel fuel consumption estimating means consumes the travel fuel consumption that is consumed when the entire travel section having a travel time less than a predetermined threshold is traveled by the driving power source of the internal combustion engine. The power consumption estimation means estimates the power consumption that is consumed when the vehicle travels with the driving force source of the electric motor in the entire travel section where the travel time is less than the predetermined threshold, and the fuel consumption estimation means determines the power consumption. The fuel consumption for power generation consumed when the power consumption is compensated by power generation by the internal combustion engine or power generation by regenerative braking in a travel section having a travel time equal to or greater than the threshold value of is estimated. Further, after the saving fuel consumption is calculated as the difference between the travel fuel consumption and the power generation fuel consumption by the saving fuel consumption calculation means, the threshold value changing means increases or decreases the predetermined threshold by a predetermined amount. The predetermined time setting means repeatedly executes the travel fuel consumption estimation means, the power consumption estimation means, the fuel consumption estimation means, the saved fuel consumption calculation means, and the threshold value changing means, and the saved fuel consumption becomes the maximum value. Is set as a predetermined time.

  That is, the predetermined time, which is a criterion for determining whether or not the entire driving section is driven by the driving force source of the electric motor, is the fuel consumption for driving when the internal combustion engine is used as the driving power source (estimating the fuel consumption for driving). Fuel consumption for power generation (estimated by the fuel consumption estimation means) when the power consumption consumed when the motor is used as the driving force source (estimated by the power consumption estimation means) The difference, that is, the saved fuel consumption (calculated by the saved fuel consumption calculation means) that can be saved when the electric motor is used as the driving force source is set to a predetermined threshold value. Thereby, the operation plan setting means (claim 1) can set an operation plan as to whether or not the entire driving section is driven by the driving force source of the electric motor based on such time. Therefore, an increase in fuel consumption due to the start of the internal combustion engine can be efficiently suppressed, and the fuel efficiency of the hybrid vehicle can be improved more reliably.

  In the invention of claim 4, since the fuel consumption for power generation is at the highest efficiency point due to the engine characteristics of the internal combustion engine, the motor is controlled based on the fuel consumption for power generation when the most efficient power generation is possible. It is possible to calculate the fuel consumption or the saved fuel consumption that can be saved when the driving force source is used. In other words, from the viewpoint of engine characteristics of the internal combustion engine, the operation plan can be set based on a predetermined time during which the fuel consumption that can be saved or the maximum value of the saved fuel consumption is obtained. Therefore, it is possible to improve the fuel consumption based on the engine characteristics of the internal combustion engine.

  In the invention of claim 5, the operation plan setting means preferentially selects, from the travel sections in which the travel time exceeds a predetermined time, the one having the longer travel section than the shorter one, and the selected Plan to make up for power consumption in the travel section. In other words, it is assigned as a travel section that compensates for power consumption in the order of the longest travel section, so based on the general power generation characteristics that the longer the stable travel time, the better the power generation efficiency Planning is possible. Therefore, it can contribute to the improvement of fuel consumption from the aspect of power generation characteristics.

  Embodiments of a control apparatus for a hybrid vehicle of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory diagram illustrating a configuration example of a hybrid vehicle and a control device thereof according to the present embodiment, and in particular, schematically illustrates a configuration example of a drive system of a hybrid vehicle and a configuration example of a control system thereof. is there. Therefore, it should be noted that the brake and clutch, and the gear mechanism that changes the gear ratio and reverses the output for reverse drive, which are necessary for actually configuring the vehicle, are omitted in FIG. .

  As shown in FIG. 1, a hybrid vehicle 10 (hereinafter referred to as “vehicle 10”) according to the present embodiment uses an engine 11 and a motor generator 12 as driving force sources, and the driving system includes an engine 11, The motor generator 12, the battery 13, the transmission 14, the differential gear 15, the drive wheels 18 and the like are configured. Specifically, for example, the output shafts of the engine 11 and the motor generator 12 are connected to the transmission 14, and further connected to the axle of the drive wheel 18 via the differential gear 15. As a result, the driving force output from the engine 11 and / or the motor generator 12 can be transmitted to the drive wheels 18. In FIG. 1, the engine 11 is represented as “E / G”, the motor generator 12 as “M / G”, the transmission 14 as “T / M”, and the differential gear 15 as “DF”.

  The engine 11 is, for example, a reciprocating type gasoline engine and can correspond to the “internal combustion engine” described in the claims. The motor generator 12 is an AC motor, for example, and has both a function as an electric motor and a function as a generator. Therefore, for example, when the rotational force of the driving wheel 18 that rotates even during braking is input to the motor generator 12 via the differential gear 15 or the transmission 14, it also functions as a generator. The motor generator 12 can correspond to an “electric motor” described in the claims.

  The battery 13 is a chargeable / dischargeable secondary battery and is electrically connected to the motor generator 12. Thereby, when the motor generator 12 functions as an electric motor, electric power is supplied to the motor generator 12 by discharging of the battery 13, and when the motor generator 12 functions as an electric generator, electric power is supplied from the motor generator 12 to the battery 13. Supplied and charged.

  The transmission 14 includes a planetary gear (not shown). For example, a planetary gear carrier shaft is connected to the engine 11, a sun gear shaft is connected to the motor generator 12, and a ring gear shaft as an output shaft is connected to the differential gear 15. Yes.

  The differential gear 15 transmits the driving force input from the transmission 14 to the left and right axles, and transmits the driving force to the left and right axles while giving a rotational difference to the left and right axles when the vehicle 10 turns a curve or the like. It is configured to be possible. Drive wheels 18 are attached to the left and right axles.

  By configuring the drive system of the vehicle 10 in this way, the engine torque output from the engine 11 can be distributed to the differential gear 15 and the motor generator 12, so that when the motor generator 12 is set to the driven state, The engine torque is transmitted to the differential gear 15 to drive the vehicle 10 and at the same time, a part of the engine torque is transmitted to drive the motor generator 12. As a result, even when the vehicle is running with the driving force of the engine 11, the motor generator 12 can generate power.

  Further, when the motor generator 12 is driven as an electric motor by supplying power from the battery 13, a resultant torque of the engine torque from the engine 11 and the motor torque from the motor generator 12 can be transmitted to the differential gear 15. Therefore, the vehicle 10 can be driven with a driving torque larger than the engine torque output from the engine 11 alone. Further, at the time of acceleration, the vehicle 10 can obtain acceleration performance higher than the horsepower performance of the engine 11 by the hybrid drive mode in which the engine 11 and the motor generator 12 are used together.

  Further, when the engine 11 is stopped and the carrier shaft of the transmission 14 is fixed, the vehicle 10 can be driven only by the driving force of the motor generator 12. In engine driving at the time of starting or at low vehicle speeds, the fuel efficiency of the vehicle 10 can be improved by setting the motor drive mode in a region where the fuel efficiency is low. Further, at the time of deceleration, the engine 11 is disconnected from the transmission 14 while the motor generator 12 is driven by the rotational force of the drive wheels 18 input to the transmission 14 via the differential gear 15, so that the energy generated by the deceleration is generated by the motor generator 12. It can be converted into electrical energy by power generation. Thereby, the electric power output from the motor generator 12 functioning as a generator can be effectively stored in the battery 13.

  Next, the configuration of the control device 20 that controls the drive system of the vehicle 10 will be described with reference to FIG. The control device 20 can correspond to a “hybrid vehicle control device” recited in the claims. The control device 20 that controls the engine 11 and the motor generator 12 described above mainly includes a vehicle controller 21 and a navigation device 24.

  The vehicle controller 21 is, for example, a peripheral LSI such as a control device as a microcomputer (hereinafter referred to as “microcomputer”), an arithmetic processing device, a storage device, an input / output interface or an A / D converter as a peripheral device thereof, or a communication device. An ASIC type MPU including an LSI or the like is configured to be able to exchange various data with the storage device 23, the navigation device 24, and various sensors (not shown). In addition to the basic system program, the storage device of the vehicle controller 21 includes a drive system control program that enables drive control of the engine 11 and the motor generator 12, a vehicle control program that enables fuel efficiency improvement control, which will be described later, and the like. Are stored, and the engine 11 and the motor generator 12 are driven and controlled by the microcomputer processing these programs.

  That is, for example, the acceleration requested by the driver of the vehicle 10 based on the opening signal input from the accelerator opening sensor, and based on the voltage signal or current signal output from the voltage / current sensor of the battery 13. By calculating the charged amount of the battery 13 and the rotational speed of the engine 11 based on the rotational speed signal input from the rotational speed sensor of the engine 11, it is possible to grasp the running state of the vehicle 10. . Therefore, select one of the engine drive mode, motor drive mode, or hybrid drive mode from the acceleration, engine speed, amount of power stored in the battery 13, vehicle speed data obtained from the storage device 23, etc. obtained from these sensors. Then, the target driving force is commanded to the engine 11 and the motor generator 12. Thereby, drive control of the engine 11 and the motor generator 12 according to a driving | running | working state is attained. As will be described later, the vehicle controller 21 cooperates with the navigation device 24 to estimate the vehicle speed pattern, divide the planned travel route, estimate the travel time, calculate the optimum time TX, set the operation schedule, and set the engine / motor. Although drive control etc. can be performed, these are explained in full detail later.

  The vehicle controller 21 is described in the claims “vehicle speed pattern estimation means, travel planned route division means, travel time estimation means, operation plan setting means, drive control means, travel fuel consumption estimation means, power consumption It can correspond to “amount estimating means, fuel consumption estimating means, saving fuel consumption calculating means, threshold changing means, predetermined time setting means”.

  The storage device 23 is, for example, a hard disk device or a semiconductor non-volatile memory device, and temporarily stores the route searched by the navigation device 24 or when the vehicle 10 travels and travels along the route. It is configured to be able to store travel data composed of acquired vehicle speed data and the like. In addition to the navigation device 24, the storage device 23 is electrically connected to the vehicle controller 21 so that the vehicle controller 21 described above can be accessed as a shared memory. Therefore, the contents stored in the storage device 23, for example, travel data including vehicle speed data, can also be referred to by the vehicle controller 21.

  In addition to a basic function such as a function for searching for a route from a departure place to a destination and a function for guiding a route according to the searched route, the navigation device 24 uses the travel data of the vehicle 10 acquired by the navigation device 24. Similar to the vehicle controller 21, for example, a control device as a microcomputer, an arithmetic processing device, a storage device, an input / output interface, an A / D converter as a peripheral device, a clock function, etc. Consists of the above-mentioned storage device 23, map database 26, gyro 27, GPS 28, vehicle speed sensor 29, display device, input / output device, etc. Has been.

  For the map database 26, for example, a large capacity storage device having a storage capacity of several hundred megabytes to several tens of gigabytes such as a CD-ROM, DVD, or hard disk device is used. The map database 26 stores map information and road information. As the road information, for example, a road network is subdivided into short distances of 10 m to several hundreds m, and is converted into data. This subdivided road is called a “road link”, and each road link is coordinated at both ends (northern latitudes), the name of the road, the number of lanes, whether it is a tunnel, whether it is elevated, and one-way. Whether it is an expressway, whether it is a highway, etc., road data, and either of the end points of the road link is an intersection, if it is an intersection, its name, identification of other road links connected to the intersection Numbers, etc. are stored.

  The GPS 28 is for outputting current position data of the vehicle 10 according to longitude and latitude, and is connected to the MPU of the navigation device 24 via an input / output interface (not shown). The GPS 28 includes a GPS receiver that receives signals from a plurality of GPS satellites and measures the absolute position of the user.

  The gyro 27 and the vehicle speed sensor 29 are for measuring the relative position of the vehicle, and are connected to the MPU of the navigation device 24 via an input / output interface (not shown). These sensors are originally used for autonomous navigation, etc., and the relative positions measured by these sensors are obtained in tunnels where the GPS receiver cannot receive radio waves from satellites, or measured by the GPS receiver. This is used for correcting the positioning error of the absolute position.

  That is, the navigation device 24 acquires the outputs of the gyro 27, the GPS 28, the vehicle speed sensor 29, and the like at regular intervals, for example, 100 milliseconds while the vehicle 10 is traveling, and acquires the acquired current position data and vehicle speed. A travel locus is calculated from data and the like, and the road on which the vehicle 10 is traveling is specified by comparing the travel locus with road information in the map database 26.

  In the present embodiment, the road link of each road identified by the navigation device 24, the vehicle speed when traveling on the road link, and the time, etc. are stored in the storage device 23 as travel data as needed. For example, when the road link reaches several hundred meters, for example, traveling data including vehicle speed data is stored every 50 meters. In addition, since travel data including vehicle speed data is stored every time the vehicle travels, when the same road link is traveled a plurality of times, travel data including a plurality of vehicle speed data is accumulated for one road link. Go. The process of specifying the road link and storing the storage data including the vehicle speed data for each road link in the storage device 23 and accumulating in this way is a travel data storage program stored in the storage device of the navigation device 24 ( The travel data storage means) is processed by the microcomputer of the navigation device 24.

  As described above, based on the travel data stored in the storage device 23 by the travel data storage program (travel data storage means), for example, a route that is frequently used, such as a commuting route that is frequently used from the usual, is used. Can be identified. In addition, since the time of the day is also recorded in the travel data, the navigation device may also indicate what day of the week (including the year, month, day) and such a route is used on a route that is frequently used. 24 can grasp.

  Thereby, for example, based on the time data when the ignition switch of the vehicle 10 is turned on and the position data of the vehicle 10, the past travel data stored in the storage device 23 is retrieved. . Then, when information related to a route that has been almost the same from the information related to the time and position and has been frequently used in the past hits, the route to be traveled from now on is the route that has been hit (For example, commuting road). In addition, it is possible to estimate a travel pattern on the predicted route based on past travel data. About the estimation method of a running pattern, it is realizable by utilizing the technique described in the previous application specification (application number: Japanese Patent Application No. 2003-68685) by the present applicant. Such specification of the planned travel route is performed by the microcomputer of the navigation device 24 performing arithmetic processing on the planned travel route specifying program (scheduled travel route specifying means) stored in the storage device of the navigation device 24.

  Next, the flow of the fuel efficiency improvement control process that is calculated by the microcomputer of the vehicle controller 21 and the navigation device 24 will be described with reference to FIGS. Here, when the motor generator 12 is caused to function as an “electric motor”, it is simply referred to as a “motor 12”.

  As shown in FIG. 2, in the fuel efficiency improvement control process, first, in step S <b> 101, a process for specifying a scheduled travel route is performed. This process is performed by the navigation device 24 executing the planned travel route specifying program described above, and can correspond to the “scheduled travel route specifying means” recited in the claims. Note that the step S101 is not limited to that performed by the planned travel route specifying program. For example, the driver of the vehicle 10 can input frequently used routes via the input device of the navigation device 24. You may perform the process which can input data.

  In the subsequent step S103, processing for estimating the vehicle speed pattern is performed. This process is performed, for example, when the microcomputer of the vehicle controller 21 performs arithmetic processing on the vehicle speed pattern estimation program stored in the storage device of the vehicle controller 21, and “vehicle speed pattern estimation means” described in the claims. It can correspond to. The vehicle speed pattern estimation method by this vehicle speed pattern estimation program is disclosed, for example, in the previous application specification (application number: Japanese Patent Application No. 2003-68685) by the applicant of the present application, and is realized by using the disclosed technology. it can.

  Here, for example, the vehicle speed pattern estimated in step S103 is illustrated in FIG. In FIG. 4, the vertical axis represents the vehicle speed, and the horizontal axis represents the elapsed time from the departure time. That is, the vehicle speed pattern is shown when the vehicle travels along the planned travel route from the starting point to the destination from the left end to the right end of the horizontal axis. In such a vehicle speed pattern, the scheduled travel route is delimited by taking a series from start to stop of the vehicle 10 as one delimiter (from start to stop as one delimiter). Such a process is performed in the next step S105.

  In step S105, a scheduled travel route dividing process is performed. This process is performed, for example, when the microcomputer of the vehicle controller 21 performs an arithmetic process on the planned travel route division program stored in the storage device of the vehicle controller 21. It can correspond to "means". For example, in the example of the planned travel route shown in FIG. 4, the sections e1 to e6 represent the travel sections divided by the step S105. Note that there are blank sections between the travel section e1 and the travel section e2, between the travel section e3 and the travel section e4, between the travel section e4 and the travel section e5, and between the travel section e5 and the travel section e6. However, these represent that the vehicle 10 has been temporarily stopped by an instruction from a traffic signal or the like, and shows that the vehicle speed has elapsed with 0 (zero).

  In the subsequent step S107, estimation processing such as travel time is performed. This process is performed, for example, when the microcomputer of the vehicle controller 21 performs an arithmetic processing on an estimation program stored in the storage device of the vehicle controller 21. ". More specifically, the travel time and the fuel consumption consumed when traveling in the hybrid drive mode are calculated for each travel section divided in step S105. For example, the travel time can be calculated by summing the lengths in the horizontal axis direction of travel sections e1 to e6 shown in FIG. The fuel consumption amount is calculated by simulating the motion state when the vehicle 10 takes the speed pattern of each travel section shown in FIG. 4 based on the motion equation modeling the dynamic characteristics of the vehicle 10. be able to.

  Here, FIG. 5 shows an example of characteristics of the travel time estimated in step S107 and the fuel consumption corresponding thereto. In FIG. 5, the travel time is plotted on the horizontal axis and the fuel consumption is plotted on the vertical axis for each of the travel sections e1 to e6 shown in FIG. Further, e * (* is an integer of 1 to 6) in the circles (circles) shown in FIG. 5 respectively correspond to the symbols e1 to e6 of the traveling section shown in FIG. As can be seen from FIG. 5, the longer the running time, the greater the fuel consumption.

  In the next step S109, the optimum time TX is calculated. This process is performed, for example, when the microcomputer of the vehicle controller 21 performs arithmetic processing on the optimum time calculation program stored in the storage device of the vehicle controller 21. Claims 2 and Claims in Claims Can correspond to 3. Specifically, the details are shown in FIG. 3. Here, the concept of the optimum time TX will be described as follows. First, Tx can correspond to a “predetermined threshold” described in the claims, and the optimum time TX can correspond to a “predetermined time” described in the claims. The optimum time TX is “the amount of fuel consumed for traveling that is consumed when the vehicle travels in the engine driving mode within the traveling section where the traveling time is within the predetermined threshold Tx” and “the traveling within the predetermined threshold Tx”. The difference with the “power consumption for power generation consumed when the power consumption consumed when traveling in the motor drive mode in the entire driving section as time is compensated by power generation by the engine 11 or power generation by regenerative braking” is the largest. It is time to become. In other words, the optimum time TX is the maximum value of time that is a reference for planning whether or not to travel all in the travel section in the motor drive mode.

  Here, the flow of the process for calculating the optimum time TX will be described with reference to FIG. As shown in FIG. 3, the process for calculating the optimum time TX starts from the process for setting the initial value of Tx in step S201. As described above, the predetermined threshold value Tx is a threshold value for selecting whether the travel section is the motor drive motor, the hybrid drive mode, or the engine drive mode based on the travel time. Therefore, for example, as a result of calculating the travel time, the shortest travel time is set as the initial value of the predetermined threshold Tx.

  In the subsequent step S203, processing for calculating the fuel consumption amount (Q1) in the short-time traveling section is performed. This process can correspond to “traveling fuel consumption estimation means” described in the claims. Specifically, the total amount of fuel consumption in the travel section in which the travel time is smaller than the predetermined threshold value Tx is calculated as Q1 with respect to the predetermined threshold value Tx that has been set. For example, assuming that a predetermined threshold Tx is set between the traveling section e2 and the traveling section e1 in FIG. 5 as shown in FIG. 5, the traveling sections e2, e4, e6 located on the left side of the predetermined threshold Tx in FIG. The fuel consumption amount Q1 of the short-time travel section is obtained by adding the fuel consumption amount of these travel times (hereinafter referred to as “short-time travel section”).

  In the next step S205, a process for calculating the motor power consumption in the short-time traveling section is performed. This process may correspond to “power consumption estimation means” described in the claims. Specifically, the power consumption by the motor 12 is calculated when it is assumed that the motor 12 travels in the entire short travel section. The calculation method uses the equation of motion of the vehicle 10 to determine the power consumption required to realize the speed pattern of each traveling section using only the motor 12 without operating the engine 11.

  In the subsequent step S207, processing for calculating the fuel consumption (Q2) necessary for power generation is performed. This processing can correspond to “fuel consumption estimation means” described in the claims. Specifically, a fuel consumption amount (Q2) for supplying the power consumption obtained in step S205 by power generation by the engine 11 is calculated. Also in this case, the calculation is performed based on the equation of motion of the vehicle 10. Here, since the power generation is performed outside the travel section in the motor drive mode, power is generated in any of the travel sections located on the right side of the predetermined threshold Tx in FIG. 5, that is, the travel sections e1, e3, e5. It will be. Again, the fuel consumption is calculated based on the equation of motion of the vehicle 10.

  First, in each travel section, the time change of the engine speed when normal hybrid control (engine drive mode or hybrid drive mode) is performed in order to realize the initially estimated speed pattern is obtained. Here, an example of the time change of the engine speed is shown in FIG. FIG. 6 is a characteristic diagram showing the relationship between the engine speed and the output torque. Note that the dot sequence marked with ◆ (black diamond) surrounded by a broken line shown in FIG. 6 represents the engine speed at each time point in the traveling section, and the x (cross) mark shown in FIG. The points of good engine efficiency are shown. Furthermore, the curve shown in FIG. 6 represents an iso-efficiency curve.

  In normal engine control, the engine speed changes as indicated by a dotted line marked with ◆ (black diamond) surrounded by a broken line in FIG. Therefore, assuming that the engine operating point is operated in the vicinity of the most efficient x (X) mark, the motor generator 12 generates power with a surplus torque that exceeds the torque required for driving the vehicle 10, and the required power generation amount The motion system that obtains enough power to cover the above is realized on the equation of motion. In step S207, the fuel consumption (W1) at this time is calculated. On the other hand, the fuel consumption (W2) in the case of normal operation, such as a dot sequence marked with ◆ (black diamond) surrounded by a broken line shown in FIG. 6, is also calculated in step S207. Then, the difference W1-W2 is calculated as the fuel amount necessary for power generation. In addition, since it is most efficient when the traveling section for generating electricity is traveling stably, starting from the traveling section e3 with the longest traveling time in FIG. 5, the traveling section e3 cannot cover the power consumption of the motor. Repeats the calculation until the power consumption of the motor is covered, assuming that power is generated even during the next long travel time e5. In this way, the fuel consumption (Q2) necessary to cover the motor power consumption is calculated. In order to cover the power consumed by the motor 12, regenerative energy at a place where deceleration is expected on the speed pattern is taken into consideration, and the amount of fuel consumption sufficient to generate power is calculated by subtracting that amount. Anyway.

  In the next step S209, Cx = (Q1-Q2) / Qtotal is calculated. This process may correspond to “saving fuel consumption calculation means” described in the claims. Here, Qtotal is the total amount of fuel consumed when normal hybrid control is performed over the entire route. In other words, Cx is an index indicating the ratio of fuel that can be saved with respect to the amount of fuel consumed when normal hybrid control is performed, and is hereinafter referred to as “fuel efficiency improvement rate”.

  In subsequent steps S211, S213, the above-described steps S203 to S209 are repeated according to some predetermined threshold values Tx. The increment of the predetermined threshold Tx set in step S213 is to increase the predetermined threshold Tx by a predetermined time interval, and is set to an appropriate value. Further, in step S213, the predetermined threshold value Tx may be decreased in increments of a predetermined time. Step S211 can correspond to “predetermined time setting means” described in the claims, and step S213 can correspond to “threshold changing means” described in the claims. .

  In the next step S215, processing for determining the optimum time TX is performed. This process can correspond to “predetermined time setting means” described in the claims, and sets a predetermined threshold value Tx at which the saved fuel consumption is the maximum value as the optimum time TX. Here, when the fuel efficiency improvement rate in step S209 becomes the highest value, the predetermined threshold Tx becomes the predetermined threshold Tx that improves the fuel efficiency most. For example, FIG. 7 shows the fuel efficiency improvement rate when the predetermined threshold value Tx of the travel time is changed with respect to the travel time distribution of FIG.

  As shown in FIG. 7, the predetermined threshold Tx is changed from threshold Tx1 to threshold Tx5. At this time, if the predetermined threshold value Tx of the travel time is too small (that is, if the travel section in the motor drive mode is reduced), the fuel efficiency improvement rate cannot be expected. However, if the predetermined threshold value Tx of the running time is increased too much, the power consumption by the motor drive mode increases, and therefore it is necessary to apply power generation even when the efficiency of the engine 11 is not so good for power generation to cover this. Increased fuel consumption. Therefore, even if the predetermined threshold value Tx for the travel time is increased too much, the fuel efficiency improvement rate decreases. As a result, as shown in FIG. 7, the fuel efficiency improvement rate has the maximum value, and in the case of FIG. 7, the fuel efficiency improvement rate becomes the largest when the threshold value is Tx3. Therefore, in the example shown in FIG. 7, the threshold value Tx3 is the predetermined threshold value Tx of the travel time determined as the optimum time TX.

  Thus, when the optimal time TX is determined in step S215, the calculation process of the optimal time TX ends, and the process proceeds to the fuel efficiency improvement control process shown in FIG. As shown in FIG. 2, in the next step S111, an operation schedule setting process is performed. This process can correspond to the “operation plan setting means” described in the claims. For example, the microcomputer of the vehicle controller 21 calculates the operation plan setting program stored in the storage device of the vehicle controller 21. Is done.

  For example, in the example of the fuel consumption with respect to the travel time shown in FIG. 5, since the threshold value Tx3 is determined as the optimum time TX in step S109, the travel section where the travel time is smaller than the threshold value Tx3, that is, the travel sections e2 and e4. , E6 is selected as a travel section in the motor drive mode. In step S207 shown in FIG. 3, since a travel section for generating necessary power is calculated, an operation schedule is set so that power generation is performed in that section. In the example shown in FIG. 5, the operation schedule finally obtained is as shown in FIG.

  That is, as shown in FIG. 8, the travel sections e2, e4, e6 are set as travel sections in the motor drive mode. Also, the portions marked “HEV” in the travel sections e1, e3, e5 represent sections that travel in the hybrid drive mode or the engine drive motor. Further, in the travel sections e5 and e3 having a longer travel time, the power generation control by the engine 11 is set in order to cover the power required for travel in the motor drive mode. At this time, it is assigned to the power generation control by the engine 11 from the longer travel time, and the power generation is performed by operating the engine 11 at the highest efficiency point as engine characteristics. This is because the longer the traveling time is, the longer the stable traveling time is, and thus it is considered that the power generation efficiency is good, and the engine 11 is most efficient by operating at the highest efficiency point. This is because it can generate electricity. In the example of the operation schedule shown in FIG. 8, the power generation amount is insufficient in the power generation only in the travel section e3 with the longest travel time, but in the travel section e5 with the next long travel time, from the beginning to the middle of the section (in FIG. 8). If the engine 11 is operated at the highest efficiency point to generate electric power, the necessary electric power can be covered.

  In step S113, engine / motor drive control processing is performed. This process can correspond to the “drive control means” described in the claims. For example, the microcomputer of the vehicle controller 21 performs arithmetic processing on the drive system control program stored in the storage device of the vehicle controller 21. Is done. Thereby, according to the driving schedule set in step S111, drive control in the engine drive mode is not performed in the travel section within the travel time within the optimum time TX. Therefore, in the travel section, the engine 11 and Switching of the driving force source with the motor generator 12 does not occur. For example, in the example of the driving schedule shown in FIG. 8, the traveling sections e2, e4, e6 are set as traveling sections in the motor drive mode, and therefore, driving control by the engine 11 is not performed in this traveling section. Drive control by the motor generator 12 is performed. Accordingly, since the engine 11 is not repeatedly started and stopped in the travel section, an increase in fuel consumption due to the start of the engine 11 can be suppressed, and the fuel consumption of the vehicle 10 can be improved.

  As described above, according to the control device 20 of the hybrid vehicle 10 according to the present embodiment, the navigation device 24 identifies the planned travel route of the vehicle 10 (S101), and the vehicle controller 21 travels along this planned travel route. The vehicle speed to be estimated is estimated as a vehicle speed pattern (S103), and the planned travel route is divided into a plurality of travel sections with the start to stop in this vehicle speed pattern as one break (S105). The vehicle controller 21 estimates the travel time required for traveling in this travel section for each travel section (S107). For travel sections whose travel time is within the optimum time TX, all of the travel sections are included. An operation plan for running in the motor drive mode is set (S111), and drive control of the vehicle 10 is performed according to this operation plan (S113).

  As a result, for a vehicle whose travel time required for traveling in the travel section is within the optimum time TX, an operation plan is set so that the entire travel section travels in the motor drive mode, and the drive control of the vehicle 10 is performed accordingly. For this reason, all of the travel section is allowed to travel by the driving force source of the motor generator 12 within the travel section in which travel is possible within the optimum time TX. That is, focusing on the time from the start to the stop (the travel time within the travel section) without depending only on the vehicle speed or the rotation speed of the engine 11, if the travel time is within the optimum time TX, Driving control using the motor generator 12 as a driving force source is performed in the entire travel section. Therefore, in general, assuming that the running state is unstable (the engine speed greatly changes) and the fuel consumption efficiency is poor, the drive control by the engine 11 is performed within the running section in which the estimated running time is within the optimum time TX. Therefore, the driving force source is not switched between the engine 11 and the motor generator 12 in the travel section. Therefore, since the engine 11 is not repeatedly started and stopped, an increase in fuel consumption due to the start of the engine 11 can be suppressed, and the fuel efficiency of the vehicle 10 can be improved. Further, by changing a predetermined threshold Tx of the travel time for selecting a travel section in the motor drive mode (S211, S213), the fuel consumption improvement rate (the fuel amount that can be saved by the present invention relative to the fuel amount required to reach the destination) The optimal time TX at which the fuel efficiency improvement rate is maximized is determined, so that an optimal fuel saving effect can be obtained.

  Note that, as described above, in the control device 20 according to the present embodiment, the drive control of the hybrid vehicle 10 configured by arranging the engine 11 and the motor generator 12 in parallel is performed. The present invention is not limited to this, and if it is a hybrid vehicle using an internal combustion engine (engine) and an electric motor (motor) as driving force sources, for example, an output shaft of the internal combustion engine (engine) and an output shaft of the electric motor (motor) The type in which the same shaft is used, or the type in which the CVT (continuously variable transmission) is used as the transmission and the input shaft of the CVT is connected to the internal combustion engine (engine) and the output shaft of the CVT is connected to the motor (motor). It can also be applied to the above. And even if it is a case where this invention is applied to such each type of hybrid vehicle, the effect | action and effect similar to the control apparatus 20 of the hybrid vehicle 10 mentioned above can be acquired.

It is explanatory drawing which shows the structural example of the hybrid vehicle which concerns on one Embodiment of this invention, and its control apparatus. It is a flowchart which shows the flow of the fuel consumption improvement control process performed by the vehicle controller which comprises the control apparatus which concerns on this embodiment. 3 is a flowchart showing a flow of processing for calculating an optimum time TX shown in FIG. It is explanatory drawing which shows an example of the vehicle speed pattern estimated by the estimation process of the vehicle speed pattern shown in FIG. FIG. 3 is a characteristic diagram illustrating an example of travel time estimated by the travel time estimation process illustrated in FIG. 2 and fuel consumption corresponding thereto. It is a characteristic figure showing the relation of the engine output torque to the engine speed. It is explanatory drawing which shows notionally the content of the calculation process of the optimal time TX shown in FIG. It is explanatory drawing which shows an example of the driving schedule set by the setting process of the driving schedule shown in FIG.

Explanation of symbols

10 ... Hybrid vehicle 11 ... Engine (internal combustion engine)
12 ... Motor generator (electric motor)
13 ... Battery 20 ... Control device (control device for hybrid vehicle)
21 ... Vehicle controller (vehicle speed pattern estimation means, travel planned route dividing means, travel time estimation means, operation plan setting means, drive control means, travel fuel consumption estimation means, power consumption estimation means, fuel consumption estimation means, Saving fuel consumption calculation means, threshold value changing means, predetermined time setting means)
23 ... Storage device 24 ... Navigation device (planned route specifying means)
26 ... Map database S101 (planned route specifying means)
S103 (vehicle speed pattern estimation means)
S105 (planned route dividing means)
S107 (traveling time estimation means)
S111 (operation plan setting means)
S113 (drive control means)
S203 (travel fuel consumption estimation means)
S205 (power consumption estimation means)
S207 (Fuel consumption estimation means)
S209 (saving fuel consumption calculation means)
S211 (predetermined time setting means)
S213 (threshold changing means)
S215 (predetermined time setting means)

Claims (5)

A control device for a hybrid vehicle using an internal combustion engine and an electric motor as a driving force source,
A planned travel route identifying means for identifying the planned travel route of the hybrid vehicle;
Vehicle speed pattern estimating means for estimating a vehicle speed traveling on the planned travel route as a vehicle speed pattern;
A scheduled travel route dividing unit that divides the planned travel route into a plurality of travel sections by separating from start to stop in the vehicle speed pattern;
Travel time estimation means for estimating the travel time required for traveling in the travel section for each travel section;
An operation plan setting means for setting an operation plan in which a travel section in which the travel time is within a predetermined time is traveled by a driving force source of the electric motor;
Drive control means for performing drive control of the hybrid vehicle according to the operation plan;
A control apparatus for a hybrid vehicle, comprising:   The predetermined time includes “a travel fuel consumption consumed when a travel section having a travel time within the predetermined time is traveled by a driving power source of the internal combustion engine” and “a travel having a travel time within the predetermined time”. The time when the difference from the “power consumption of power generation consumed when supplementing the power consumption consumed by running the section with the driving force source of the electric motor by power generation by the internal combustion engine or power generation by regenerative braking” is maximized The hybrid vehicle control device according to claim 1, wherein the control device is a hybrid vehicle control device. A travel fuel consumption estimation means for estimating a travel fuel consumption consumed when the travel section having the travel time less than a predetermined threshold is traveled by the driving force source of the internal combustion engine;
Power consumption estimation means for estimating a power consumption consumed when traveling by a driving force source of the electric motor in a travel section having the travel time less than the predetermined threshold;
Fuel consumption estimation for estimating power consumption for power generation that is consumed when the power consumption is compensated by power generation by the internal combustion engine or power generation by regenerative braking within a travel section having the travel time equal to or greater than the predetermined threshold. Means,
Saving fuel consumption calculating means for calculating a saving fuel consumption as a difference between the traveling fuel consumption and the power generation fuel consumption;
Threshold calculating means for increasing or decreasing the predetermined threshold by a predetermined amount after calculating the saved fuel consumption;
The travel fuel consumption estimation means, the power consumption estimation means, the fuel consumption estimation means, the saved fuel consumption calculation means, and the threshold value changing means are repeatedly executed, and the saved fuel consumption becomes the maximum value. A predetermined time setting means for setting a predetermined threshold as the predetermined time;
The hybrid vehicle control device according to claim 1, comprising:   4. The control device for a hybrid vehicle according to claim 2, wherein the fuel consumption for power generation is at a maximum efficiency point according to engine characteristics of the internal combustion engine.   The operation plan setting means preferentially selects a long travel section from the travel sections in which the travel time exceeds the predetermined time over a shorter travel section, and the selected travel section The hybrid vehicle control device according to any one of claims 2 to 4, wherein the power consumption is planned to be compensated.

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