Control plan creation system

Abstract

To provide a technique for reducing the possibility that the temperature of a friction brake becomes excessive.SOLUTION: A sharing ratio determining unit configured to determine a sharing ratio that is a ratio at which each of the friction brake, a regenerative brake configured to generate electric power by the motor generator, and a thermal brake configured to generate a larger amount of heat by reducing energy conversion efficiency of the motor generator to be lower than predetermined efficiency is responsible for the deceleration force at each position on the scheduled traveling route; The control plan creation system includes: SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a control plan creation system. [Background technology]

[0002] Conventionally, vehicles capable of using both friction braking and regenerative braking have been known. In such vehicles, when the battery's SOC reaches an upper limit, the regenerative braking cannot be used, and the vehicle must be decelerated using only the friction braking. When decelerating the vehicle using only the friction braking, a technique is known in which the auxiliary equipment is forcibly driven before the vehicle reaches the braking-heavy section to lower the battery's SOC value in order to prevent the friction brake temperature from exceeding a predetermined temperature in the braking-heavy section (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-170445 Summary of the Invention [Problem to be solved by the invention]

[0004] When a vehicle is decelerated using both friction and regenerative braking, if the regenerative braking is unavailable or if the deceleration force of the regenerative braking is small, the deceleration force of the friction brake increases, and the temperature of the friction brake may rise above a predetermined temperature. If the SOC value is lowered by forcibly driving the auxiliary equipment, as in the conventional technology described above, it becomes possible for the regenerative braking to generate energy equivalent to the lowered SOC value. However, even when the regenerative braking is used in this way, the temperature of the friction brake may still rise above a predetermined temperature. The present invention has been made in consideration of the above-mentioned problems, and aims to provide a technique for reducing the possibility that the temperature of a friction brake will become excessive. [Means for solving the problem]

[0005] In order to achieve the above object, the control plan creation system comprises a planned driving route acquisition unit that acquires a planned driving route for a vehicle equipped with a friction brake and a motor generator; a deceleration force acquisition unit that acquires the deceleration force for each position when the vehicle travels on the planned driving route; and a sharing ratio determination unit that determines the sharing ratio, which is the proportion of the deceleration force that each of the friction brake, the regenerative brake that generates electricity using the motor generator, and the heat generation brake that reduces the energy conversion efficiency of the motor generator below a predetermined efficiency to increase the amount of heat generated, will bear at each position on the planned driving route.

[0006] That is, the vehicle can select from friction brakes, regenerative brakes, and heat-generating brakes as brakes that provide deceleration force for each position when traveling along a planned travel route. This configuration increases the number of brakes that can provide deceleration force compared to a configuration in which regenerative brakes provide as much deceleration force as possible and friction brakes provide the remaining deceleration force. As a result, it becomes possible for brakes other than friction brakes to provide more deceleration force. Therefore, it is possible to reduce the possibility of the temperature of the friction brakes becoming excessive. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram showing the configuration of a control plan creation system. [Figure 2] FIG. 3 is a diagram for explaining control of a motor generator. [Figure 3] 10 is a flowchart of a control plan creation process. [Figure 4] 10A and 10B are diagrams for explaining the gradient of a planned travel route, deceleration force, SOC, and temperature of a friction brake according to an example. [Figure 5] 10A and 10B are diagrams for explaining the gradient of a planned travel route, deceleration force, SOC, and temperature of a friction brake according to an example. [Figure 6] 10A and 10B are diagrams for explaining the gradient of a planned travel route, deceleration force, SOC, and temperature of a friction brake according to an example. [Figure 7] 10 is a flowchart of a control plan creation process. DETAILED DESCRIPTION OF THE INVENTION

[0008] Here, the embodiments of the present invention will be described in the following order. (1) Configuration of the control plan creation system: (2) Control plan creation process: (3) Control plan execution process: (4) Other embodiments:

[0009] (1) Configuration of the control plan creation system: FIG. 1 is a block diagram showing the configuration of a control plan creation system according to one embodiment. In this embodiment, the control plan creation system is a system used to create a vehicle control plan for traveling a planned travel route before the vehicle starts traveling. In this embodiment, the control plan creation system is implemented by an ECU (Electronic Control Unit) 10 mounted on an electric vehicle and including a CPU, RAM, ROM, etc. The vehicle according to this embodiment is a Battery Electric Vehicle (BEV) mounted with a battery 50, which is a rechargeable storage battery, and is driven by supplying the electric power stored in the battery 50 to a motor generator 30.

[0010] The vehicle includes an ECU 10, a navigation device 20, a motor generator 30, an inverter 40, a battery 50, a friction brake 60, and auxiliary equipment 70. The navigation device 20 is a device for guiding the vehicle to a destination. The navigation device 20 includes a storage medium for storing map information, a position acquisition device for identifying the current location of the vehicle, and a display unit. The navigation device 20 searches for a planned driving route from a departure point to a destination based on the map information, and guides the vehicle using a map display or the like so that the vehicle can travel along the planned driving route based on the current location of the vehicle.

[0011] Map information is information indicating roads, facilities, etc., and may be defined in various ways. For example, a configuration including node data, link data, shape interpolation point data, and facility data may be employed. Node data is data indicating the location of intersections. Link data indicates road sections and is associated with nodes corresponding to the endpoints of the road sections. In other words, link data indicates links connecting nodes. In this embodiment, link data also includes information indicating road attributes of the road sections indicated by the link data. Road attributes include, for example, information indicating expressways, general roads, narrow streets, etc. Link data also includes shape interpolation point data indicating the locations of shape interpolation points for identifying the shape of the road between nodes. Link data also includes information indicating the gradient of the road section. The gradient may be represented in various ways, such as by defining the gradient at each position every fixed distance, or by defining the average gradient of the road section. Facility data indicates the name, location, and attributes of facilities located near the road. In this embodiment, facilities include various types of facilities, and may be starting points or destinations.

[0012] The motor generator 30 is a device that functions as an electric motor and a generator. The battery 50 is a source of DC power. In this embodiment, the battery 50 is capable of outputting information indicating the SOC (State Of Charge) of the battery to the ECU 10. The SOC is a value that indicates the state of charge of the battery 50 in a range of 0 to 100%, with a completely discharged state of the battery 50 being regarded as 0% and a fully charged state of the battery 50 being 100%. The battery 50 may be controlled by an ECU that exchanges information with the ECU 10. The ECU is omitted in FIG. 1. The same applies to other devices, where an ECU may be used to obtain information about various devices provided in the vehicle.

[0013] Inverter 40 is a power conversion device connected to motor generator 30 and battery 50, and converts power between the direct current of battery 50 and the multi-phase alternating current (e.g., three-phase alternating current) of motor generator 30. The vehicle is equipped with a power transmission mechanism (not shown), such as a transmission and a transaxle, and the power output from motor generator 30 is transmitted to the wheels via the power transmission mechanism.

[0014] In this embodiment, the power output from the motor generator 30 is used to drive the vehicle forward or backward. That is, the motor generator 30 is rotated by AC power converted from DC power of the battery 50 via the inverter 40, and the power generated by this rotation drives the vehicle (power running). The motor generator 30 is also rotated by the rotational driving force transmitted from the wheels of the vehicle, and when this rotation generates AC power, the AC power is converted into DC power via the inverter 40. The converted DC power is used to charge the battery 50 (regeneration).

[0015] The friction brake 60 is a device that applies a deceleration force to the vehicle by applying a friction force to a rotating body that rotates integrally with the wheels. The deceleration force is a force in the opposite direction to the direction of travel of the vehicle. The friction brake 60 of this embodiment is a so-called hydraulic brake device that applies friction force by bringing brake pads into contact with the rotating body using the hydraulic pressure of brake fluid. The friction brake 60 also includes a temperature sensor (not shown) that detects the temperature of the friction brake 60, and is capable of outputting information indicating the temperature of the friction brake 60 to the ECU 10.

[0016] The accessories 70 are devices other than the motor generator 30 and other equipment necessary for running the vehicle, and are operated by power supplied from the battery 50. The accessories 70 include, for example, a high-voltage hot water heater (HVH), an air conditioner, a light device, a wiper device, and the like.

[0017] The ECU 10 executes programs recorded in a ROM (not shown) to perform various functions. In this embodiment, the programs include a control plan creation program. Execution of the program causes the ECU 10 to function as a control plan creation system. When the control plan creation program is executed, the ECU 10 functions as a planned travel route acquisition unit 10a, a deceleration force acquisition unit 10b, a sharing ratio determination unit 10c, and a control plan unit 10d.

[0018] The planned driving route acquisition unit 10a has a function of acquiring a planned driving route for the vehicle. That is, the ECU 10 acquires the planned driving route from the navigation device 20 using the function of the planned driving route acquisition unit 10a. Specifically, the navigation device 20 performs a route search using the current location of the vehicle as a starting point and a point specified by the user as a destination, and acquires the planned driving route. Once the planned driving route is acquired, information indicating the planned driving route is transmitted to the ECU 10. The ECU 10 acquires the planned driving route by acquiring the transmitted information. In this embodiment, the information indicating the planned driving route includes the permutation of road sections that make up the planned driving route, i.e., the permutation of links. Furthermore, each link is associated with information indicating the gradient of the road section and information indicating the road attributes of the road section.

[0019] The deceleration force acquisition unit 10b has a function of acquiring the deceleration force for each position when the vehicle travels along the planned travel route. That is, the ECU 10 uses the function of the deceleration force acquisition unit 10b to acquire the vehicle speed when the vehicle travels along the planned travel route, and acquires the deceleration force required for traveling at that vehicle speed for each position on the planned travel route.

[0020] The sharing ratio determination unit 10c has a function of determining the sharing ratio, which is the ratio at which the friction brake 60, the regenerative brake, and the heat generation brake each bear the deceleration force at each position on the planned traveling route. Here, the regenerative brake is a brake that applies a deceleration force to the vehicle by generating electricity using the motor generator 30. Specifically, the rotational driving force of the wheels is transmitted to the motor generator 30 via a power transmission mechanism, and when the motor generator 30 rotates, the rotational torque energy is converted into electrical energy. In this series of energy conversion processes, a deceleration force is applied to the vehicle, functioning as a brake. In the regenerative brake, a portion of the rotational torque that rotates the motor generator 30 is converted into electrical energy and used to charge the battery 50. In addition, a portion of the rotational torque is converted into thermal energy.

[0021] The heat generation brake is a brake that increases the amount of heat generated by reducing the energy conversion efficiency of the motor generator 30 below a predetermined efficiency. In this embodiment, the motor generator 30 is controlled by a vector control method. Figure 2 is a diagram for explaining the control of the motor generator 30, showing the configuration related to the control in the motor generator 30 and the inverter 40.

[0022] The inverter 40 includes a processor 41 and a switching element 42. The processor 41 is an integrated circuit that controls the on / off of the switching elements included in the inverter 40. The switching element 42 is an element that realizes conversion between DC power and AC power between the battery 50 and the motor generator 30 by combining the on / off states of these elements. Such power conversion can be realized by a known circuit in which circuits in which upper and lower switching elements are connected in series are connected in parallel for multiple phases (three in the case of three phases). The switching element 42 is preferably a power semiconductor element capable of operating at high frequencies, and can be realized by, for example, an IGBT.

[0023] The processor 41 operates the switching element 42 by PWM control using a vector control method, causing the motor generator 30 to perform powering operation and regenerative operation. These operations are usually controlled so that the energy conversion efficiency is a predetermined efficiency (generally the maximum efficiency). Powering operation is an operation in which electrical energy is converted into rotational energy, and is controlled so that the energy conversion efficiency when torque is generated by electricity supplied to the motor generator 30 is a predetermined efficiency. Regenerative operation is an operation in which rotational energy is converted into electrical energy, and is controlled so that the energy conversion efficiency when electricity is generated by torque supplied to the motor generator 30 by the power transmission mechanism is a predetermined efficiency.

[0024] Specifically, the processor 41 performs PWM control using a vector control method that performs feedback control to control the current I flowing through the windings of the winding unit 31 so that it approaches a predetermined value. In vector control, the d-axis is defined as the direction of the north pole (magnetic pole position) of a magnet that is assumed to rotate with the rotor, and the q-axis is defined as a direction that advances from this in terms of an electrical angle of π / 2. A dq-axis rotating coordinate system is then established, consisting of the d-axis and q-axis, which rotate in synchronization with the rotor's rotation in terms of the electrical angle. In vector control, current command values ​​Ids and Iqs are determined for current components in the respective axial directions of the dq-axis rotating coordinate system. The current command values ​​Ids and Iqs are determined so that the energy conversion efficiency of the motor-generator 30 becomes a predetermined efficiency (generally, maximum efficiency).

[0025] In order to ensure that currents corresponding to the current command values ​​Ids and Iqs flow through the windings, the motor generator 30 is provided with a current sensor 32, which outputs current values ​​Iu, Iv, and Iw for the U, V, and W phases of the winding section 31. The processor 41 acquires the current values ​​Iu, Iv, and Iw of the winding section 31, and a current axis converter 41a performs three-phase to two-phase conversion and rotating coordinate conversion based on the magnetic pole positions to convert the current values ​​Iu, Iv, and Iw into two-phase currents Id and Iq expressed in a dq-axis rotating coordinate system.

[0026] The processor 41 then uses the feedback calculation unit 41b to calculate command values ​​for voltages to be applied to the winding unit 31 so that the two-phase currents Id and Iq approach the current command values ​​Ids and Iqs. The command values ​​for voltage obtained by the feedback calculation unit 41b are two-phase voltage values ​​Vd and Vq expressed in a dq-axis rotating coordinate system. Various feedback control methods can be used, such as PI control.

[0027] Furthermore, the processor 41 uses a voltage axis converter 41c to perform fixed coordinate conversion and two-phase-to-three-phase conversion based on the magnetic pole positions to convert the two-phase voltage values ​​Vd and Vq into three-phase AC voltage values ​​Vu, Vv, and Vw, which are AC voltage values ​​applied to the windings of each of the three phases. Furthermore, the processor 41 uses a PWM controller 41d to compare each of the three-phase AC voltage values ​​Vu, Vv, and Vw with a reference voltage waveform (e.g., a triangular wave) and generate three-phase control signals Uu, Uv, and Uw so that a rectangular pulse wave is turned on when each of the three-phase AC voltage values ​​Vu, Vv, and Vw exceeds the reference voltage waveform and turned off when each of the three-phase AC voltage values ​​Vu, Vv, and Vw falls below the reference voltage waveform. The processor 41 then controls the switching elements 42 based on the three-phase control signals Uu, Uv, and Uw. Specifically, the switching elements 42 include a drive circuit (not shown), which turns each of the switching elements 42 on or off based on the three-phase control signals Uu, Uv, and Uw from the PWM controller 41d.

[0028] The motor generator 30 normally operates using the above-described vector control and converts power at a predetermined efficiency. The heat generation control is a control that deliberately reduces the energy conversion efficiency during normal operation. Therefore, when the heat generation control is performed during power running, the power consumption of the battery 50 increases compared to when the heat generation control is not performed. Furthermore, when the heat generation control is performed during regenerative operation, a deceleration force equivalent to the extra energy consumed by heat is added to the deceleration force obtained by regenerative braking when the heat generation control is not performed. Therefore, it is possible to further increase the deceleration force in addition to the regenerative braking force. In this way, the portion of the deceleration force when the heat generation control is performed that exceeds the deceleration force obtained by regenerative braking when the heat generation control is not performed is considered to be the deceleration force obtained by the heat generation brake.

[0029] When performing heat generation control, the processor 41 controls the inverter 40 in PWM control so as to reduce the energy conversion efficiency below a default efficiency. Specifically, the processor 41 reduces the efficiency by changing the current command values ​​Ids and Iqs so that they are different from the current command values ​​Ids and Iqs used in vector control. In this embodiment, a plurality of combinations (Ids1, Iqs1 to Idsn, Iqsn: n is an integer of 2 or more) of the current command values ​​after the change are assumed in advance, and the deceleration force due to the heat generation brake obtained when each combination is selected is specified in advance. The correspondence between the combination of current command values ​​and the deceleration force may be stored in a memory (not shown) or the like.

[0030] When one of a plurality of deceleration forces is output by the heat generation brake, the processor 41 inputs a combination of current command values ​​corresponding to the desired deceleration force to the feedback calculation unit 41b. As a result, the desired deceleration force can be obtained by the heat generation brake. Note that if the deceleration force by the regenerative brake varies when the heat generation brake is used compared to when the heat generation brake is not used, the combination of the deceleration force by the heat generation brake and the deceleration force by the regenerative brake is stored in a memory (not shown) or the like.

[0031] In this embodiment, as described above, deceleration is possible using the heat generation brake in addition to the friction brake 60 and the regenerative brake. Therefore, the sharing ratio determination unit 10c of the ECU 10 creates a control plan for the planned travel route by determining the sharing ratio of the deceleration force required when traveling along the planned travel route. In other words, the ECU 10 determines the sharing ratio so that the deceleration force for each position on the planned travel route is borne by the friction brake 60, the regenerative brake, and the heat generation brake.

[0032] The process for determining the sharing ratio will be described in detail later. Once the sharing ratio of the deceleration force at each position on the planned travel route is determined, the sharing ratio becomes a control plan for the planned travel route. Information indicating the control plan is stored in the RAM of the ECU 10, for example. As described above, in this embodiment, deceleration force can be applied to the vehicle using not only the friction brake 60 and the regenerative brake, but also the heat generation brake. Therefore, there is less need to rely on the friction brake compared to a vehicle that can use only the friction brake 60 and the regenerative brake. This reduces the possibility that the temperature of the friction brake 60 will become excessive.

[0033] The control plan unit 10d includes a function for creating a control plan for the vehicle along the planned travel route and a function for controlling the vehicle in accordance with the control plan. That is, the ECU 10 creates the control plan based on the sharing ratio determined by the function of the sharing ratio determination unit 10c. Note that, as will be described in detail later, the control plan may include a plan for heat generation control of the motor generator 30 in flat sections or uphill sections.

[0034] When executing the control plan, the ECU 10, using the function of the control planning unit 10d, acquires the current location of the vehicle from the navigation device 20 and acquires the brake distribution ratio at the current location by referring to the control plan. The ECU 10 also, using the function of the control planning unit 10d, acquires the deceleration force requested by the user at the current location from the amount of operation of the foot pedal by the user. The ECU 10 then, using the function of the control planning unit 10d, controls each brake so that the brake distribution ratio responsible for the deceleration force becomes the distribution ratio indicated in the control plan. If the control plan includes a plan to perform heat generation control on the motor-generator 30 in a flat section or an uphill section, the ECU 10 controls the current command value in the corresponding section to become the planned command value.

[0035] (2) Control plan creation process: Next, the control plan creation process executed by the ECU 10 will be described. Fig. 3 is a flowchart of the control plan creation process. Fig. 4 is a diagram for explaining the gradient, deceleration force, SOC, and temperature of the friction brake 60 of a certain planned travel route. In Fig. 4, the horizontal axis represents position. The top row shows a schematic representation of the gradient for each position. In the second to fourth rows from the top, the vertical axis represents the deceleration force, SOC, and temperature of the friction brake 60. The temperature and SOC of the friction brake 60 have upper limits, which are indicated by dashed lines.

[0036] The control plan creation process is executed in response to a predetermined trigger, for example, when a new planned driving route is set in the navigation device 20. When the control plan creation process starts, the ECU 10 acquires a planned driving route using the function of the planned driving route acquisition unit 10a (step S100). The planned driving route is information indicating a route from the departure point to the destination of the vehicle, which is searched by the navigation device 20. In this embodiment, this information includes link data of the links that make up the planned driving route. Therefore, this information includes the gradient and road attributes of each link.

[0037] Next, the ECU 10 sets section boundaries based on the gradient of the planned travel route using the function of the deceleration force acquisition unit 10b (step S105). Here, the section boundaries are boundaries of sections where the road gradient changes within a certain range. That is, the ECU 10 sets sections where the road gradient changes within a certain range, and sets the start point and end point of the sections as the section boundaries.

[0038] Specifically, ECU 10 identifies the gradient of the planned driving route and identifies gradient variations based on the information on the planned driving route acquired in step S100. For example, if a gradient is defined for each road section (each link), ECU 10 acquires the absolute value of the difference in gradient between adjacent road sections, and if the absolute value of the difference is less than a threshold, combines the adjacent road sections and regards them as one section whose gradient variations are within a certain range. If a gradient is defined for each position, ECU 10 acquires the absolute value of the difference in gradient between adjacent positions, and if the absolute value of the difference is less than a threshold, regards a section whose start point and end point are adjacent positions as one section whose gradient variations are within a certain range.

[0039] When a section is defined in which the gradient varies within a certain range, the start and end points of that section become the section boundaries. In the example shown in Figure 4, points A, B, C, and D after the departure point S are set as section boundaries on the planned route from departure point S to destination G. For example, section Z1 from departure point S to point A is a gentle descent, while section Z2 from point A to point B is a steep descent, with the average gradients of the two sections being different. The sections from point B to point C, point C to point D, and point D to destination G are called sections Z3, Z4, and Z5, respectively.

[0040] Next, the ECU 10 acquires the vehicle speed for each section using the function of the deceleration force acquisition unit 10b (step S110). The vehicle speed may be acquired using various methods. Here, an example is assumed in which the vehicle speed for each section is acquired using the average vehicle speed for each road section. Specifically, the ECU 10 refers to the road attributes included in the information about the planned travel route, and considers the average vehicle speed corresponding to the road attributes of the road section to be the vehicle speed for each road section. The average vehicle speed corresponding to the road attributes may be predetermined, for example, 80 km / h on expressways, 60 km / h on general roads, and 30 km / h on narrow streets.

[0041] If the road between the section boundaries set in step S105 is made up of multiple road sections (links), ECU 10 uses the average vehicle speeds of those road sections to obtain the average vehicle speed for the entire section. In the example shown in Fig. 4, when the average vehicle speed for each section is obtained, the average vehicle speed for each of sections Z1 to Z5 has been obtained. Of course, the method for obtaining the vehicle speed is just one example, and the vehicle speed may also be obtained based on the gradient or congestion level of each road section, vehicle speed statistics, measured values, etc. Furthermore, the vehicle speed for each location may be specified in more detail.

[0042] Next, ECU 10 acquires the deceleration force for each section using the function of deceleration force acquisition unit 10b (step S115). In this embodiment, ECU 10 acquires the deceleration force for each section based on the gradient for each section set in step S105 and the vehicle speed for each section acquired in step S110. That is, ECU 10 acquires, for each section, the deceleration force required to travel on a road with the gradient of that section at the vehicle speed for that section. The deceleration force may be acquired by various methods. For example, the deceleration force may be acquired by assuming that, in order to move linearly on a descending gradient at a constant vehicle speed, a deceleration force is applied to the vehicle so as to cancel out the acceleration acting on the vehicle on the descending gradient.

[0043] In this case, the ECU 10 acquires the acceleration a acting on the vehicle based on the gradient angle and the pre-specified vehicle mass m, and can obtain the deceleration force F = m × a. If the vehicle speed does not match the vehicle speed for the section at the beginning, the vehicle can accelerate or decelerate to match the vehicle speed for the section. After that, a deceleration force is applied to cancel out the acceleration acting on the vehicle, allowing the vehicle to travel at a constant speed through the section. For simplicity, FIG. 4 omits the adjustment of vehicle speed at the beginning of the section, and shows the deceleration force for each section as a constant value. In this embodiment, the deceleration force is specified for downhill sections, but not for flat sections or uphill sections. The above method of acquiring the deceleration force is merely an example, and the deceleration force for each position may be acquired in more detail based on the detailed gradient, vehicle speed, vehicle specifications, etc. for each position. The deceleration force for a road section with a gradient of 0 (flat road) is 0, and the acceleration force is specified for an uphill section.

[0044] Next, the ECU 10 determines the brake sharing ratio for each position using the function of the sharing ratio determination unit 10c. When determining the sharing ratio, the ECU 10 determines the sharing ratio by preferentially allocating the deceleration force for each position to the regenerative brake, preferentially allocating the remaining deceleration force to the friction brake, and preferentially allocating the remaining deceleration force to the heat generation brake. By determining the sharing ratio according to this policy, the regenerative brake is used preferentially and the remaining deceleration force is borne by the friction brake 60, thereby making it possible to control the temperature of the friction brake 60 to be as low as possible. Furthermore, by determining the sharing ratio so as to give priority to using the friction brake 60 over the heat generation brake, it is possible to suppress the use of the heat generation brake, which reduces energy conversion efficiency, as much as possible and prevent an excessive decrease in energy efficiency.

[0045] To achieve this allocation, the sharing ratio is determined so that the regenerative brake shares the maximum amount of the required deceleration force that it can bear, the friction brake 60 shares the maximum amount of the remaining deceleration force that it can bear, and the heat generation brake shares the remaining deceleration force.

[0046] Specifically, the ECU 10 acquires the regenerative braking share ratio (step S120). At this time, the ECU 10 first acquires the SOC on the assumption that the regenerative brakes will share the maximum possible deceleration force in the downhill road section, and the friction brake 60 will share the remaining deceleration force. In this embodiment, setting the deceleration force that can be shared by the regenerative brakes to the maximum possible deceleration force means that the vehicle travels without the SOC exceeding an upper limit value and the deceleration force is set so that the SOC at a specific reference point becomes the upper limit value. In other words, the ECU 10 sets the deceleration force shared by the regenerative brakes to a deceleration force that maximizes the amount of power charged to the battery 50 while the vehicle travels along the planned travel route to the reference point.

[0047] If a deceleration force greater than this deceleration force is set, the SOC will exceed the upper limit, and it will not be possible to charge the electric power generated by regenerative braking. In this sense, the deceleration force that maximizes the amount of electric power charged to the battery 50 during the course of traveling to the reference point is the maximum value of the deceleration force. In this embodiment, the maximum value of the deceleration force that can be provided by regenerative braking is achieved by maximizing the amount of electric power charged to the battery 50 during the course of traveling of the section in which the vehicle travels to the reference point. It is sufficient that the amount of electric power be maximized over the entire section, and the deceleration force at each position does not have to match the maximum value of the deceleration force that can be provided by regenerative braking at that position at that moment.

[0048] The reference point may be determined by various methods, such as the end of a descending gradient or destination G. The end of a descending gradient is the point where the increased SOC due to the use of regenerative braking on the descending gradient reaches a maximum value, so a limit is imposed so that the SOC does not exceed an upper limit at the end of the descending gradient. Furthermore, if the SOC is maximized at destination G, it is possible to reduce the possibility of an SOC shortage in the next trip, which is preferable. Figure 4 shows an example in which the SOC is maximized at destination G because destination G is the end of a descending gradient.

[0049] Once the reference point where the SOC should be maximized is identified, ECU 10 sets a target section whose end point is the reference point and whose start point is located before the end point, and identifies an increase in SOC based on an SOC decrease in the target section. The target section may be set using various methods. For example, it may be the entire section from the departure point S to the destination G, or multiple target sections may be set between the departure point S and the destination G. In the example shown in FIG. 4, sections Z1 and Z2 are one target section, and sections Z3, Z4, and Z5 are one target section. Here, an example will be described in which the entire section from the departure point S to the destination G is the target section.

[0050] The SOC decrease may be determined by various methods, such as a method in which the SOC decrease per unit distance for each gradient is determined in advance and the SOC decrease is determined according to the gradient of the target section. More specifically, if the SOC decrease per unit distance in the powering section, for example, a flat road and an uphill gradient section, is determined for each gradient, the ECU 10 can determine the SOC decrease based on the distance of the flat road or uphill gradient section included in the target section. Note that if the SOC decrease also occurs in a downhill gradient section, the SOC decrease in the downhill gradient section may also be determined.

[0051] Here, an example is assumed in which the SOC decrease on a flat road and an uphill gradient section is identified. Therefore, for example, in the example shown in FIG. 4, the SOC decrease on section Z3, which is a flat road, is identified. Once the SOC decrease on the target section is identified, the ECU 10 obtains the current SOC from the battery 50 and regards it as SOC0 at the departure point S. Furthermore, the ECU 10 obtains the minimum value SOCmin by subtracting the SOC decrease ΔE on the target section from the SOC0 on the departure point S. The ECU 10 then regards the SOC upper limit value SOCmax-minimum value SOCmin as the chargeable SOC amount ΔSOC corresponding to the amount of electric energy that can be charged on the target section.

[0052] The ECU 10 determines the deceleration force so that the regenerative brake can provide the necessary deceleration force on the downhill slope of the target section, thereby charging the battery 50 with the chargeable amount ΔSOC. In this embodiment, the increase in SOC resulting from traveling a unit distance at a given deceleration force is determined in advance. The ECU 10 provisionally determines the deceleration force for each downhill slope, determines the increase in SOC for each downhill slope by multiplying the increase in SOC per unit distance corresponding to the provisionally determined deceleration force by the distance, and repeatedly determines whether the increase in SOC for the entire target section matches the chargeable amount ΔSOC. When the increase in SOC for the entire target section matches the chargeable amount ΔSOC, the deceleration force has been determined to maximize the amount of power charged to the battery 50 during the vehicle's travel to the reference point.

[0053] Once the deceleration force provided by the regenerative brakes is determined, ECU 10 obtains the regenerative brake share ratio at each location based on the deceleration force provided by the regenerative brakes and the deceleration force at each location obtained in step S115. Of course, in the process of determining the deceleration force, constraints may be imposed, such as ensuring that the SOC does not exceed an upper limit at any point before destination G. Alternatively, a lower limit may be set for the SOC, and the regenerative brake share ratio may be determined so that the SOC does not fall below the lower limit.

[0054] Next, ECU 10 acquires the sharing ratio of friction brake 60 (step S125). Here, ECU 10 acquires the remaining ratio of the deceleration force borne by the regenerative brake among the deceleration force at each position as the sharing ratio of friction brake 60. FIG. 4 shows an example of the sharing ratio, assuming that the deceleration force acquired in step S115 is shared between the regenerative brake and friction brake 60 as described above. That is, FIG. 4 shows that part of the deceleration force is borne by the regenerative brake (hatched by a straight line extending from the upper right to the lower left), and the remaining deceleration force is borne by friction brake 60 (hatched by a straight line extending from the upper left to the lower right).

[0055] Next, the ECU 10 acquires the temperature of the friction brake 60 using the function of the sharing ratio determination unit 10c (step S130). That is, the ECU 10 acquires the transition of the estimated temperature of the friction brake 60 when traveling along the planned travel route. Specifically, the ECU 10 acquires the current temperature of the friction brake 60 from the friction brake 60 and regards it as the temperature of the friction brake 60 at the departure point S. Then, the ECU 10 estimates the temperature of the friction brake 60 based on the deceleration force and distance that the friction brake 60 will bear after the departure point S. Note that the temperature rise of the friction brake 60 per unit distance is predetermined for each deceleration force, and the ECU 10 estimates the temperature of the friction brake 60 by integrating the temperature rise due to the deceleration force at each position according to the distance traveled with that deceleration force.

[0056] Next, the ECU 10 determines whether or not there is a position where the temperature of the friction brake 60 is equal to or higher than a threshold value, using the function of the sharing ratio determination unit 10c (step S135). Here, the threshold value is the upper limit value of the temperature that is allowed for the friction brake 60. In the example shown in FIG. 4, at a position P1 just before the destination G, the temperature of the friction brake 60 exceeds the upper limit value indicated by the dashed line.

[0057] If it is not determined that there is a position where the temperature of the friction brake 60 is equal to or higher than the threshold, the ECU 10 skips steps S145 to S165. On the other hand, if it is determined that there is a position where the temperature of the friction brake 60 is equal to or higher than the threshold, the ECU 10, using the function of the sharing rate determination unit 10c, acquires the SOC for each position when heat generation control is performed in the powering section before the section where the temperature is equal to or higher than the threshold (step S140). That is, the ECU 10 reduces the energy conversion efficiency when rotating the motor generator 30 using the electric power of the battery 50 in the powering section compared to normal. As a result, the SOC in the powering section is lower than when heat generation control is not performed, and therefore it becomes possible to perform additional regenerative braking that generates energy equivalent to the reduced SOC.

[0058] The SOC that is extra consumed per unit distance due to heat generation control in the powering section is specified in advance. The SOC that is extra consumed per unit distance due to heat generation control may be a fixed value or may be selectable from multiple values. In the former case, it is sufficient to specify one set of current command values ​​instead of the current command values ​​Ids and Iqs that result in a predetermined efficiency. In the latter case, it is sufficient to specify multiple sets of current command values ​​and select one.

[0059] Here, we assume an example in which the extra SOC consumed per unit distance due to heat generation control is a fixed value. ECU 10 determines the amount of SOC reduction in the powering section based on the distance of the powering section. If there are multiple powering sections, heat generation control may be performed in one or more sections before the section where the temperature of the friction brake 60 is above the threshold. If there are two or more powering sections, the section closest to the section where the temperature of the friction brake 60 is above the threshold may be prioritized as the section where heat generation control is performed. Figure 5 shows a state in which the SOC is reduced by using the heat generation brake in section Z3, which is a powering section, in an example similar to Figure 4.

[0060] Next, ECU 10 acquires the regenerative braking ratio (step S145). That is, the ratio is acquired so that the excess SOC created by the processing of step S140 is shared by the regenerative braking. That is, in the section after the section targeted for the processing of step S145, the regenerative braking ratio is increased by a ratio that can restore the SOC that was reduced in step S140.

[0061] Next, ECU 10 acquires the sharing ratio of friction brake 60 (step S150). Here, a ratio equivalent to the sharing ratio of regenerative brake increased in step S145 is reduced from the sharing ratio of friction brake 60. In the example shown in Fig. 5, this sharing ratio is reflected, and the sharing ratio of regenerative brake in sections Z4 and Z5 has increased and the sharing ratio of friction brake 60 has decreased compared to Fig. 4.

[0062] Next, the ECU 10 acquires the temperature of the friction brake 60 by the function of the sharing rate determination unit 10c (step S155). That is, the ECU 10 acquires the transition of the estimated temperature of the friction brake 60 in the section where the corrections were made in steps S140 to S150.

[0063] Next, the ECU 10 determines whether or not there is a position where the temperature of the friction brake 60 is equal to or higher than the threshold value by using the function of the sharing ratio determination unit 10c (step S160). In the example shown in Fig. 5, the temperature of the friction brake 60 exceeds the upper limit indicated by the dashed line at a position P2 just before the destination G.

[0064] If it is not determined that there is a position where the temperature of the friction brake 60 is equal to or higher than the threshold, the ECU 10 skips step S165. On the other hand, if it is determined that there is a position where the temperature of the friction brake 60 is equal to or higher than the threshold, the ECU 10, using the function of the sharing rate determination unit 10c, obtains the sharing rate of the heat generation brake in the downhill section before the section where the temperature of the friction brake 60 is equal to or higher than the threshold (step S165). Specifically, the ECU 10 increases the sharing rate at which the heat generation brake bears the deceleration force in the downhill section where the temperature is equal to or higher than the threshold from 0. The ECU 10 also increases the sharing rate at which the heat generation brake bears the deceleration force in the downhill section before the downhill section where the temperature is equal to or higher than the threshold from 0. The deceleration force that the heat generation brake can bear is set so that the friction brake 60 is used preferentially over the heat generation brake, while preventing the temperature of the friction brake 60 from exceeding the upper limit. Various methods can be used to determine the deceleration force of the heat generation brake. Here, it is assumed that a plurality of deceleration forces can be selected as the deceleration force of the heat generation brake (that is, a plurality of combinations of current command values ​​for heat generation control are determined).

[0065] The ECU 10 selects the deceleration force of the heat generation brake in a downhill gradient section where the temperature of the friction brake 60 is equal to or higher than a threshold value from a plurality of selectable deceleration forces. In this case, the ECU 10 selects a deceleration force such that the heat generation brake provides the minimum deceleration force within a range where the temperature of the friction brake 60 is lower than the threshold value. The selection of the minimum deceleration force can be realized, for example, by temporarily selecting a deceleration force from a plurality of selectable deceleration forces, obtaining the SOC for each position obtained by the temporarily selected deceleration force, and repeating a process of determining whether or not there is a position at the SOC where the temperature of the friction brake 60 is equal to or higher than a threshold value.

[0066] If, in a downhill gradient section where the temperature of the friction brake 60 is equal to or higher than the threshold, the temperature of the friction brake 60 does not fall below the threshold even when the maximum selectable deceleration force is selected, the ECU 10 processes sections that are closer to the downhill gradient section where the temperature of the friction brake 60 is equal to or higher than the threshold, in order of proximity, and performs the same processing. In other words, the ECU 10 selects the deceleration force of the heat generation brake in the section to be processed so that the temperature of the friction brake 60 falls below the threshold. With the above configuration, it is possible to prevent the temperature of the friction brake 60 from becoming excessive while suppressing a decrease in efficiency due to the use of the heat generation brake.

[0067] When the deceleration force of the heat generation brake in each section is determined so that the temperature of the friction brake 60 is lower than the threshold, the heat generation brake's share ratio is obtained based on the deceleration force, and the same ratio as the heat generation brake's share ratio is subtracted from the friction brake 60's share ratio to determine the share ratios of the heat generation brake, friction brake 60, and regenerative brake. As described above, of the remaining deceleration force to be borne by the regenerative brake, the friction brake 60 shares the maximum value that the friction brake 60 can bear, and it is possible to determine the share ratio so that the heat generation brake also bears the remaining deceleration force. That is, in this embodiment, it is considered that excessive use of the friction brake 60 to the extent that the temperature of the friction brake 60 exceeds the upper limit should be avoided, and the friction brake 60 is capable of bearing deceleration force within a range where the temperature does not exceed the upper limit. Therefore, when the share ratio of the deceleration force borne by the friction brake 60 is set to the maximum value within a range where the temperature of the friction brake 60 does not exceed the upper limit, it can be said that the share ratio of the remaining deceleration force to be borne by the regenerative brake is set to the maximum value that the friction brake 60 can bear. Fig. 6 shows an example similar to Fig. 4, in which the temperature of the friction brake 60 is reduced below the threshold by increasing the heat generation brake's share ratio above 0. The deceleration force provided by the heat generation brake is indicated by cross-hatching.

[0068] In step S165, the ECU 10 acquires the heat generation brake share ratio, or if it is determined in step S135 or step S160 that there is no location where the temperature of the friction brake 60 is equal to or higher than the threshold, the ECU 10 creates a control plan using the function of the control plan unit 10d (step S170). The control plan may be defined in various ways as long as it is a control plan for the vehicle traveling along the planned route from the departure point S to the destination G. Specifically, the ECU 10 generates information as a control plan in which the share ratio for each location determined by the processing before step S170 is set as the control target value for the friction brake 60, regenerative brake, and heat generation brake at each location. Note that, if there is a powering section where heat generation control is performed in step S140, the section and the target for heat generation control in that section (e.g., a combination of current command values) are included in the information indicating the control plan. The generated control plan is stored in a RAM (not shown) or the like.

[0069] (3) Control plan execution process: Next, a control plan execution process for executing a control plan will be described. When the vehicle starts traveling with a control plan created based on the process shown in Fig. 3, the control plan execution process is started. When the control plan execution process is started, the ECU 10 acquires the control plan (step S200). That is, the ECU 10 acquires information indicating the control plan stored in a RAM or the like (not shown).

[0070] Next, the ECU 10 executes the control plan (step S205). Specifically, the ECU 10 acquires the current location of the vehicle from the navigation device 20 and identifies the content of control to be executed at the current location by referring to the control plan. In this embodiment, when the current location is a descending gradient section, the control plan specifies the allocation ratios of the friction brake 60, the regenerative brake, and the heat generation brake at the current location. Therefore, the ECU 10 acquires the amount of operation of the foot pedal by the user based on information transmitted from the friction brake 60, and acquires the deceleration force required by the user at the current location based on the amount of operation. Then, the ECU 10 controls each brake using the function of the control plan unit 10d so that the allocation ratio of each brake becomes the allocation ratio at the current location.

[0071] Specifically, the ECU 10 multiplies the deceleration force requested by the user by the sharing ratio of the friction brake 60 to obtain the deceleration force that the friction brake 60 should provide. The ECU 10 then outputs a control signal to the friction brake 60, controlling it so that the deceleration force is output by the friction brake 60. The ECU 10 also multiplies the deceleration force requested by the user by the sharing ratio of the regenerative brake to obtain the deceleration force that the regenerative brake should provide. The ECU 10 then outputs a control signal to the inverter 40, causing the motor generator 30 to control the motor generator 30 so that the deceleration force is the deceleration force that the regenerative brake should provide.

[0072] Furthermore, ECU 10 multiplies the deceleration force requested by the user by the heat generation brake's sharing ratio to obtain the deceleration force that the heat generation brake should provide. ECU 10 then outputs a control signal to inverter 40 to change the current command value so that the deceleration force is the deceleration force that the heat generation brake should provide. Note that in the above processing related to each brake, if the sharing ratio is 0, the deceleration force provided by that brake is 0, and therefore that brake is not used.

[0073] Furthermore, if the control plan includes a plan to perform heat generation control on the motor generator 30 in a flat section or an uphill section, and the current location is a flat section or an uphill section where heat generation control is to be performed, the ECU 10 outputs a control signal to the inverter 40 to perform heat generation control, i.e., changes the current command value so that the heat generation efficiency is lower than normal.

[0074] When the control plan for the current location is executed, the ECU 10 determines whether an error serving as an index for determining whether the control plan is as planned is equal to or greater than a threshold (step S210). Here, the error may be an index for determining whether the control plan is as planned, and various errors may be used as the index. For example, the error may be an error between the planned value and the actual value of the temperature or SOC of the friction brake 60. The threshold may be a value that is predetermined to determine whether the error is outside an allowable range.

[0075] When the error between the planned value and the actual value of the temperature of the friction brake 60 is used as an index, the control plan includes the temperature of the friction brake 60 for each position identified in the planning stage. For example, in the example shown in FIG. 6, the temperature of the friction brake 60 for each position shown in the bottom row is included in the control plan. In this case, the ECU 10 acquires the current temperature from the friction brake 60 as the actual value, and acquires the temperature of the friction brake 60 at the current position defined in the control plan as the planned value. Then, the absolute value of the difference between the two is acquired and compared as a threshold value.

[0076] When the error between the planned SOC value and the actual SOC value is used as an index, the control plan includes the SOC for each location identified in the planning stage. For example, in the example shown in FIG. 6, the control plan includes the SOC for each location shown in the second row from the bottom. In this case, the ECU 10 obtains the current SOC from the battery 50 as the actual value, and obtains the SOC at the current location specified in the control plan as the planned value. Then, the absolute value of the difference between the two is obtained and compared as a threshold.

[0077] If it is determined in step S210 that the error is not equal to or greater than the threshold, the ECU 10 repeats the processing from step S205 onwards. That is, the ECU 10 performs the processing from step S205 onwards every time the vehicle travels a certain distance or for a certain period of time. If it is determined in step S210 that the error is equal to or greater than the threshold, the ECU 10 reacquires the control plan (step S215). That is, the ECU 10 re-executes the processing shown in FIG. 3 to re-create a control plan from the current location onwards. Then, the ECU 10 repeats the processing from step S205 onwards. According to the above processing, it is possible to reduce the possibility that the temperature of the friction brake 60 will become excessive while the vehicle is traveling along the planned travel route. Note that the loop processing of steps S205 to S215 in the control plan execution processing is repeated until the vehicle reaches the destination G, and the control plan execution processing ends when the vehicle reaches the destination G.

[0078] (4) Other embodiments: The above-described embodiment is merely an example for implementing the present invention, and various other embodiments are also possible. For example, at least a portion of the control plan creation system may be realized by a server capable of communicating with a communication device provided in a vehicle, or may be realized by a portable device such as a smartphone or tablet carried in the vehicle. Furthermore, the control plan creation system may be realized by multiple devices (e.g., a portable device and an on-board device, or a portable device, a remote server, and an on-board device). At least some of the planned driving route acquisition unit 10a, deceleration force acquisition unit 10b, allocation ratio determination unit 10c, and control plan unit 10d that constitute the control plan creation system may be distributed across multiple devices. Furthermore, some of the components of the above-described embodiment may be omitted, and the order of processing may be changed or omitted.

[0079] Furthermore, the error that serves as an index for determining whether the control plan is as planned is not limited to the temperature or SOC of the friction brake 60. For example, the error between the actual measured value and the planned value of the deceleration force may be used as the index. Furthermore, the error evaluation is not limited to a configuration that evaluates an instantaneous value, and a cumulative value of the error over distance or time may be obtained.

[0080] Furthermore, when determining the SOC decrease in step S120, decreases other than those due to powering may be considered. Such decreases in SOC may be caused by the accessories 70. For example, in winter, the SOC decreases when air conditioning is used, and the SOC decreases when various accessories 70 are operated along the planned travel route. Therefore, in step S120, the SOC decrease due to the operation of the various accessories 70 may be determined, and the sum of the SOC decrease and the decrease due to powering may be obtained and used to determine the share of the deceleration force of the regenerative brake. In this case, the ECU 10 creates a control plan including the operating state of the accessories 70 for each position, and when executing the control plan, the ECU 10 operates the accessories 70 at each position indicated by the control plan.

[0081] Furthermore, the method for determining the regenerative braking share ratio in step S120 described above is merely an example, and various other methods may be used to determine the share ratio. For example, a regenerative braking share ratio corresponding to an arbitrary gradient or deceleration force may be determined in advance, and the regenerative braking share ratio may be determined according to the gradient or deceleration force of the planned travel route.

[0082] Furthermore, in the above-described embodiment, if the temperature of the friction brake 60 exceeds the threshold when only the regenerative brake and the friction brake 60 are used, the heat generation control is performed in the powering section, but the heat generation control in the powering section may be omitted. That is, it is also possible to adopt a configuration in which steps S135 to S155 are omitted.

[0083] The planned driving route acquisition unit may acquire a planned driving route of a vehicle equipped with a friction brake and a motor generator. Various configurations may be used to acquire the planned driving route. For example, a planned driving route generated by an external device such as a server may be supplied to the control plan creation system via communications. Furthermore, the vehicle is not limited to an electric vehicle that is driven by supplying power stored in a battery to the motor generator as long as it is equipped with a friction brake and a motor generator. For example, the vehicle may be a plug-in hybrid vehicle or a hybrid vehicle.

[0084] The friction brake may be any device that can apply a deceleration force to the vehicle by friction between a member that rotates integrally with the wheel and a member attached to the vehicle body. Therefore, the type of brake is not limited, and various types of brakes, such as disc brakes or drum brakes, can be used. Furthermore, instead of using hydraulic brake fluid, an actuator may use electricity to activate the friction brake. The motor generator may be any device that can be rotated by electricity and rotated by the vehicle's kinetic energy to generate electricity. Therefore, the size, type, number, etc., of the motor generator are not limited, and various types may be used.

[0085] The deceleration force acquisition unit only needs to acquire the deceleration force for each position when the vehicle travels along the planned travel route. The deceleration force for each position only needs to be defined so that a vehicle control plan can be created. The interval between positions is not limited, and deceleration forces may be defined for each discrete position, or a continuous deceleration force for a continuous section may be defined. Various configurations are possible.

[0086] The deceleration force may be any force necessary for traveling along the planned travel route, and in order to suppress temperature rise in the friction brakes, it is sufficient to mainly acquire the deceleration force in downhill sections. However, if it is predicted that deceleration force will be applied to the vehicle in flat sections or uphill sections, the deceleration force may also be defined for these sections. The method for acquiring the deceleration force is not limited to the above-mentioned embodiment. For example, the deceleration force for each road section or each location may be acquired based on the vehicle's past travel history and its statistical values, or the deceleration force for each road section or each location may be acquired based on a learning model generated by machine learning.

[0087] The sharing ratio determination unit must be able to determine the sharing ratios, which are the proportions of deceleration force that each of the friction brake, the regenerative brake that generates electricity using the motor generator, and the heat generation brake that increases the heat generation by reducing the energy conversion efficiency of the motor generator below a predetermined efficiency, will share at each position on the planned travel route.In other words, the sharing ratio determination unit must be able to select at least one method from the three methods of friction brake, regenerative brake, and heat generation brake and determine the sharing ratio of deceleration force for each position.With this configuration, the friction brake and regenerative brake can be used, and it is sufficient that the configuration can be configured to reduce the frequency of using the friction brake compared to a configuration in which the heat generation brake cannot be used.

[0088] Various methods may be used to determine the ratio of braking force to decelerating wheels. For example, if the brake with the highest priority for providing deceleration force is not a friction brake, it is highly likely that the temperature of the friction brake can be prevented from rising excessively.

[0089] The control planning unit may create a vehicle control plan for the planned travel route based on the braking ratio. The control plan may be defined in various ways. For example, the control plan may include not only the braking ratio of each brake but also the deceleration force as a control target value.

[0090] Furthermore, the techniques of the present invention can also be applied as programs or methods. The above-described systems, programs, and methods may be realized as standalone devices or may be realized using components shared with various parts of a vehicle, and thus include various aspects. They can also be modified as appropriate, such as being partly software and partly hardware. Furthermore, the invention can also be realized as a recording medium for a program that controls the system. Of course, the recording medium for the program may be a magnetic recording medium or a semiconductor memory, and any recording medium developed in the future can be considered in the same way. [Explanation of symbols]

[0091] 10...ECU, 10a...planned driving route acquisition unit, 10b...deceleration force acquisition unit, 10c...sharing ratio determination unit, 10d...control planning unit, 20...navigation device, 30...motor generator, 31...winding unit, 32...current sensor, 40...inverter, 41...processor, 41a...current axis conversion unit, 41b...feedback calculation unit, 41c...voltage axis conversion unit, 41d...PWM control unit, 42...switching element, 50...battery, 60...friction brake, 70...auxiliary equipment

Claims

1. a planned driving route acquisition unit that acquires a planned driving route of a vehicle that is equipped with a friction brake and a motor generator; a deceleration force acquisition unit that acquires a deceleration force for each position when the vehicle travels along the planned travel route; a sharing ratio determination unit that determines a sharing ratio, which is a ratio of the deceleration force to be shared by each of the friction brake, the regenerative brake that generates electricity using the motor generator, and the heat generation brake that increases the heat generation by reducing the energy conversion efficiency of the motor generator below a predetermined efficiency, at each position on the planned traveling route; A control plan creation system comprising:

2. The sharing ratio determination unit The deceleration force for each position is preferentially allocated to the regenerative brake; the remaining deceleration force is preferentially allocated to the friction brake; The remaining deceleration force is allocated to the heat generation brake to determine the allocation ratio. The control plan creation system according to claim 1 .

3. the sharing ratio determination unit determines the sharing ratio in a descending gradient section, a control planning unit that creates a control plan for the vehicle along the planned travel route based on the allocation ratio; The control planning unit When it is impossible to bear the deceleration force at each position by the regenerative brake and the friction brake in the descending gradient section, the control plan is created so that heat generation control in which the energy conversion efficiency is reduced below a predetermined efficiency to increase the amount of heat generated is performed in a flat section or an ascending gradient section.

3. The control plan creation system according to claim 1 or 2.

4. The sharing ratio determination unit determining the sharing ratio so that the sharing ratio of the heat generating brake in a downhill gradient section before a section where the deceleration force for each position cannot be borne by the regenerative brake and the friction brake is greater than 0; 3. The control plan creation system according to claim 1 or 2.

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