JP5470747B2 - Motor control device - Google Patents

Description

  The present invention relates to a drive control device for a vehicle, and more particularly to a control device that increases or decreases a driving force in accordance with a road gradient.

A vehicle including an electric motor as a driving force source is known. Patent Document 1 includes a gradient sensor (G sensor), and controls the torque response of the electric motor according to the road gradient detected by the gradient sensor. The apparatus which performs the driving | operation support at the time of starting so that the adjustment amount of an accelerator operation amount may be reduced by performing is disclosed.
JP 2005-0667603 A

  However, since the gradient sensor has variations due to the state of attachment to the vehicle in addition to variations in characteristics due to temperature changes and deterioration, variations in individual sensors, etc., gradient detection accuracy is not necessarily high. Furthermore, it is difficult to detect the gradient with high accuracy because it is affected by the longitudinal G generated in the vehicle when the vehicle suddenly stops. Therefore, with the apparatus disclosed in Patent Document 1, it is difficult to obtain an appropriate driving support at the time of starting, and in some cases, the drivability may be deteriorated.

  Therefore, an object of the present invention is to realize driving support at an accurate start.

The present invention relates to a drive motor for driving a vehicle, an accelerator operation detecting means for detecting an accelerator operation of a driver, a brake operation detecting means for detecting a brake operation of the driver, and a motor torque adjustment for controlling a supply current to the drive motor. A torque command value calculating means for calculating a torque command value for the drive motor based on an accelerator operation, and further comprising a stepping on the brake based on a detection value of the brake operation detecting means A brake depression amount calculation means for calculating the amount, an operation system response speed calculation means for calculating a response speed to the operation system of the driver based on a detection value of at least one of the accelerator operation detection means and the brake operation detection means, and a brake depression amount A slope estimator that estimates the road slope at the current position of the vehicle based on the control system response speed And a torque response determining means for determining a torque response of the drive motor according to a road gradient when the vehicle starts, wherein the motor torque adjusting means supplies the current supplied to the drive motor based on the motor torque command value and the torque response. To control. The gradient estimation means estimates that the vehicle is on an uphill road when the brake depression amount is equal to or greater than a predetermined threshold and the operation system response speed is equal to or greater than the predetermined first threshold, and the brake depression amount is equal to the predetermined threshold. be more than, and operating system response speed is estimated that in downhill in the case of less than a predetermined first threshold value smaller than the second threshold value, when the amount of brake pedal depression is smaller than a predetermined threshold value, and the brake depression amount is If the operating system response speed is less than the first threshold and greater than the second threshold, the road is estimated to be a flat road.

  According to the present invention, since the road gradient of the current vehicle position is estimated based on the brake depression amount and the operation system response speed, it is possible to set the torque response at the start according to the road gradient without using the gradient sensor. Driving support can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram showing an example of a system configuration to which this embodiment is applied. 1 is a drive motor, 2 is an inverter that controls the drive of the drive motor 1, 3 is a power source that is a power supply source to the drive motor 1, 4 is a controller that controls the inverter 2, the power source 3, and the like, and 5 is an accelerator pedal , 6 is a brake pedal, 7 is an accelerator switch sensor for detecting whether or not the accelerator pedal 5 is depressed, and 8 is a brake depression amount sensor for detecting the depression amount of the brake pedal 6. The unit of the depression amount of the brake pedal 6 is [mm].

  One drive motor 1 is arranged per vehicle as shown in FIG. 1 and drives wheels via a drive shaft (not shown). Note that two or four drive motors 1 per vehicle may be arranged in the wheel of the drive wheel to directly drive the wheel. Further, as the drive motor 1, for example, a three-phase induction motor is used.

  As the power source 3, for example, a power plant system including a fuel cell stack, a battery, or the like can be used.

  The controller 4 calculates the drive motor torque commanded to the inverter 2 from the detection value of the accelerator switch sensor 7 and the vehicle speed detected by a vehicle speed sensor (not shown), and further estimates the power consumption of the drive motor 1 and takes out the power from the power source 3. Is calculated. Based on these calculation results, the inverter 2 and the power source 3 are controlled. Details of the calculation executed by the controller 4 will be described later.

  As described above, in a vehicle that travels by driving wheels by the drive motor 1, the number of gear stages of the transmission is generally 1 or a small number according to the same, and the accelerator pedal opening and the motor torque are further reduced. Correspond one-on-one. Therefore, regardless of the driving situation, the vehicle only performs uniform acceleration / deceleration corresponding to the accelerator operation. Therefore, it is not easy for the driver to perform a smooth driving according to the driving situation. For example, when starting acceleration on an uphill road, it is desirable that the amount of change in vehicle acceleration (torque response) relative to the amount of accelerator operation is large. On the other hand, it is desired that the torque response is small on the downhill road. However, as described above, the configuration in which the accelerator pedal opening and the motor torque are in one-to-one correspondence, that is, the accelerator operation amount and the torque response are in one-to-one correspondence does not meet such a requirement. As a result, a desired acceleration / deceleration cannot be obtained unless the driver adjusts the accelerator operation amount in accordance with the road gradient.

  On the other hand, driving support control in which a gradient sensor (G sensor) is mounted on the vehicle and the magnitude of the torque response of the drive motor 1 at the start is adjusted according to the detected value of the gradient sensor is conceivable. However, even if the road slope is the same, the torque response required by the driver differs depending on the driving skill level. For example, even on a downhill road with the same slope, a driving beginner feels more scared than an advanced person. Want a smaller torque response than the advanced. That is, in the driving support control by adjusting the torque response according to the road gradient, there may be a situation where sufficient support cannot be obtained depending on the driving skill level of the driver.

  Therefore, in the present embodiment, driving support at the start is performed by the control described below.

  FIG. 2 is a control block diagram showing a basic configuration for controlling the drive motor 1 in the system of FIG. As shown in FIG. 2, a brake depression amount detection unit B101 that detects the brake depression amount of the driver, a driver operation system response speed detection unit B102 that detects the operation response speed of the driver operation system (accelerator pedal and brake pedal), and the brake In order to control the drive motor 1 based on the drive motor torque command value response and the drive motor torque command value response determination unit B103 that determines the torque response commanded to the drive motor 1 based on the depression amount and the driver operation system response speed. And a drive motor control unit B104 for controlling the inverter 2 and the power source 3.

  FIG. 12 is a flowchart of drive motor control executed by the controller 4. This control is executed every predetermined time (for example, every 10 [ms]) from the start of the motor control.

  In step S2001, the maximum value of the brake depression amount of the driver is calculated by executing a subroutine described later.

  In step S2002, the operation response speed of the driver's operation system (accelerator pedal 5 and brake pedal 6) is calculated by executing a subroutine described later.

  In step S2003, the duration of the state in which the accelerator pedal 5 is depressed (accelerator ON state) is calculated by executing a subroutine described later.

  In step S2004, it is determined whether or not the accelerator ON state continuation time is shorter than a predetermined threshold value set in advance. If it is shorter, the process proceeds to step S2006, and if it is longer, the process proceeds to step S2005.

  In step S2005, the brake depression maximum value and the driver operation system response speed are reset to zero.

  In step S2006, the drive motor 1 is instructed by searching a map to be described later using the brake depression maximum value calculated in step S2001 and the driver operation response speed (brake OFF operation response speed) calculated in step S2002. Determine the torque response.

  In step S2007, a subroutine to be described later is executed to calculate a drive motor torque command value based on the torque response determined in step S2006.

  In step S2008, the drive motor 1 is controlled by adjusting the current supplied to the drive motor 1 by the inverter 2 based on the drive motor torque command value calculated in step S2007. Thereafter, this routine is repeated.

  It is determined whether or not a re-brake operation has been performed between step S2003 and step S2004 or between step S2004 and step S2006. If a re-brake operation has been performed, the process proceeds to step S2005. If not, the process may proceed to step S2004 or step S2006. The “re-brake operation” here refers to an operation of depressing the brake pedal 6 again after returning from a state where the brake pedal 6 is depressed to a state where the depression amount is zero.

  By performing this determination and the determination in step S2004, it is possible to eliminate the influence of the adjustment of the brake depression amount performed for vehicle speed control or the like when determining the torque response described later.

  FIG. 13 is a flowchart for calculating the maximum brake depression amount executed in step S2001.

  In step S2101, the current value of the brake depression amount output from the brake depression amount sensor 8 is detected.

  In step S2102, the previous value that is the brake depression amount before a predetermined time is stored. Note that the predetermined time represents the calculation cycle (for example, 10 [ms]) of the controller 4, but due to the influence of sensor noise, etc., when high calculation cannot be performed in the same calculation cycle, There are a method of expanding the time when it is difficult to be affected, and a method of performing a first-order lag filtering process for removing the influence of sensor noise.

  In step S2104, the current value of the brake depression amount is compared with the previous value. If the current value is larger, the process proceeds to step S2104. If the previous value is larger, the process proceeds to step S2105.

  In step S2104, the brake depression amount maximum value is updated to the current value. In step S2105, the brake depression amount maximum value is maintained as the previous value, and the process is terminated.

  FIG. 3 is a time chart showing a change in the maximum brake depression amount when the control of FIG. 13 is executed. The horizontal axis of the chart indicates one calculation cycle of the controller 4.

  Since the brake depression amount is zero between time zero and t1, the maximum value also remains zero. When the brake pedal 6 is depressed at time t1, the maximum value is updated. Since the brake depression amount is smaller at time t2 than at time t1, the maximum value is held as the previous value. When the amount of brake depression exceeds the amount of depression at time t1 at time t3, the maximum value is updated. Thereafter, the same processing is repeated. At time t5, the maximum value is once reset to zero.

  This is because the brake operation amount at time t5 corresponds to the re-brake operation because the brake depression amount is zero at time t4. Also, the reason why the maximum value is reset at time t7 is that a predetermined time has elapsed since the accelerator was turned on at time t6, so that the maximum value was reset to zero in step S2005 of FIG.

  In addition, although the predetermined time after becoming an accelerator ON state is made into the time for two cycles here, it is not limited to the time for two cycles, What is necessary is just the time before and behind this.

  FIG. 14 is a flowchart for driver operation system response speed detection executed in step S2002 of FIG. Here, the “driver operation system response speed” is a speed of change from the ON state of the brake pedal 6 to the OFF direction (brake OFF operation speed [mm / sec]).

  Steps S2201 and S2202 are the same as steps S2101 and S2102 in FIG.

  In step S2203, it is compared whether or not the current value of the brake depression amount is smaller than the previous value. If the current value is smaller, the process proceeds to step S2204. If the previous value is smaller, the process proceeds to step S2205.

  In step S2204, the brake OFF operation speed is calculated, and the process ends. The brake OFF operation speed is obtained by dividing the amount of change from the previous value of the brake depression amount to the current value by the calculation cycle.

  In step S2205, the previous value of the brake OFF operation speed is held, and the process ends.

  FIG. 5 is a time chart showing a change in brake OFF operation speed when the control of FIG. 14 is executed. One scale on the horizontal axis of the time chart indicates one calculation cycle of the controller 4.

  The brake pedal 6 is depressed at time t1, but since the depression amount is larger than the previous value, the brake OFF operation speed is maintained at the previous value, that is, zero.

  When the amount of brake depression at the time t2 falls below the amount of depression at the time t1, the brake OFF operation speed increases. When the brake depression amount increases again at time t3, the depression amount becomes larger than the previous value, so that the brake OFF operation speed is maintained at the value at time t2. Thereafter, this process is repeated.

  Note that the brake OFF operation speed is reset to zero at time t4 and time t6 for the same reason as in FIG.

  FIG. 15 is a flowchart for the accelerator ON state duration calculation performed in step S2003 of FIG.

  In step S2301, the accelerator switch sensor 7 detects the ON / OFF state of the accelerator pedal 5.

  In step S2302, it is determined whether or not the accelerator is on. If it is ON, the process proceeds to step S2303, and if it is OFF, the process proceeds to step S2304.

  In step S2303, the accelerator ON state duration counter is incremented. In step S2304, the accelerator ON state duration counter is reset to zero, and the process ends.

  FIG. 4 is a diagram illustrating a method of calculating the accelerator ON state duration. One scale on the vertical axis and the horizontal axis indicates one calculation cycle of the controller 4.

  Until the accelerator is turned on at time t1 and until the accelerator is turned off at time t2, the accelerator on state duration counter is continuously incremented every calculation cycle, and the counter is reset to zero at time t2.

  FIG. 6 is a map used for determining the torque response executed in step S2006 of FIG. The vertical axis represents the brake OFF operation response speed [mm / sec], and the horizontal axis represents the maximum brake depression amount [mm].

  When the brake depression amount is equal to or greater than the first brake depression amount and the brake OFF operation response speed is equal to or greater than the first operation response speed, the first torque response is selected. When the brake depression amount is equal to or greater than the first brake depression amount and the brake OFF operation response speed is equal to or less than the second operation response speed, the second torque response is selected. Outside the region where the first torque response or the second torque response is selected, that is, when the brake depression amount is equal to or less than the first brake depression amount, and the brake depression amount is equal to or greater than the first brake depression amount, and the brake OFF operation response speed is the first When the operation response speed is less than 1 and greater than the second operation response speed, the third torque response is selected.

  The first brake depression amount is a boundary value between the brake depression amount on an uphill road or a downhill road and the brake depression amount on a flat road. On flat roads, the amount of brake depression is smaller than that on uphill and downhill roads. By using this boundary value, can the vehicle's current position be a flat road, or it can be other than a flat road? Can be determined. Since this boundary value varies depending on the vehicle weight, brake specifications, and the like, those previously examined through experiments or the like are used.

  The first operation response speed is a boundary value between a brake OFF operation response speed on an uphill road and a brake OFF operation response speed on a flat road. On an uphill road, the speed drop when the brake is depressed is faster than on a flat road, so the response speed of the brake-off operation tends to be faster than that on a flat road. Can be determined whether the road is an uphill road or a flat road.

  The second operation response speed is a boundary value between a brake OFF operation response speed on a downhill road and a brake OFF operation response speed on a flat road. On downhill roads, if the amount of brake depression is small, the vehicle is accelerated by the action of gravity, so the brake-off operation tends to be slower than on a flat road. As this boundary value, a value obtained through an experiment or the like in advance is used.

  By setting the first brake depression amount and the first and second operation response speeds as described above, the first torque response is selected when starting on an uphill road, and the second torque response is selected when starting. When starting on a slope, the third torque response is selected when starting on a flat road. That is, the first torque response is a faster torque response than when starting on a flat road, and the second torque response is a slower torque response than when starting on a flat road, so the response speed of each torque response is It becomes a relationship like this.

First torque response> Third torque response> Second torque response Note that the maximum brake depression amount and the brake OFF operation response speed are reset to zero when a re-brake operation is performed or after a predetermined time has elapsed since the accelerator was turned on. Therefore, the third torque response is selected.

  By the way, for example, when driving on an uphill road, beginners of driving tend to step on the brakes more than advanced drivers. And, since the brake is decelerated more than expected by depressing the brake more than necessary, the brake OFF operation becomes faster. That is, it becomes easier for a beginner to enter the first response torque region. In consideration of traveling downhill, beginners of driving are more fearful of the slope than advanced drivers, so the amount of brake depression is large and the brake-off operation tends to be slow. That is, it becomes easy to enter the second torque response region.

  On the other hand, an advanced driver can perform an appropriate brake operation according to the gradient when traveling on an uphill road, so the amount of brake depression is smaller and the brake OFF operation response speed is slower than a beginner. When traveling downhill, the fear of the slope is weaker than that of a beginner, so the amount of brake depression is small and the brake OFF operation response speed tends to be high. That is, it becomes easy to enter the third torque response region.

  Therefore, it is easier for beginners to receive torque assistance when starting on an uphill or downhill road, and advanced drivers are less likely to receive unnecessary torque assistance. As a result, torque assistance corresponding to the level of driving skill is performed. It becomes.

  FIG. 7 is a time chart showing a torque command value to the drive motor 1 when the brake operation shown in FIGS. 3 and 5 is performed. The brake operation, the maximum brake depression amount, the brake OFF operation response speed, and the accelerator switch ON / OFF are the same as in FIGS. 3 and 5, respectively. The torque commanded to the drive motor 1 is a creep torque. The example shown in FIG. 7 shows a vehicle incorporating control for limiting the creep torque when the brake pedal 6 is depressed.

  After the brake operation is started at time t1, when the brake depression amount becomes zero at time t2, a torque response is selected based on the torque response determined in step S2006 of FIG. Here, since the maximum brake depression amount is larger than the first brake depression amount and the brake OFF operation response speed is equal to or higher than the first operation response speed, the first torque response indicated by the solid line in FIG. 7 is selected. For comparison, the second and third torque responses are indicated by broken lines.

  Further, after the re-brake operation is started at time t3, when the brake depression amount becomes zero at time t4, the torque response is selected in the same manner. Here, since the maximum brake depression amount is smaller than the first brake depression amount, and the brake OFF operation response speed is less than the first operation response speed and greater than the second operation response speed, the third line indicated by the solid line in FIG. A torque response is selected.

  As described above, according to the present embodiment, the following effects can be obtained.

  (1) A drive motor 1 that drives the vehicle, an accelerator switch sensor 7 that detects the driver's accelerator operation, a brake depression sensor 8 that detects the driver's brake operation, and an inverter that controls the current supplied to the drive motor 1 2, torque command value calculation means for calculating a torque command value for the drive motor 1 based on the accelerator operation, brake depression amount calculation means for calculating the brake depression amount based on the detection value of the brake depression amount sensor 8, accelerator switch An operation system response speed calculating means for calculating a response speed of the driver to the operation system based on a detection value of at least one of the sensor 7 and the brake depression amount sensor 8, and a vehicle current position based on the brake depression amount and the operation system response speed. Gradient estimation means for estimating the road gradient, and depending on the road gradient when the vehicle starts And a controller 4 as a torque response determining means for determining the torque response of the drive motor 1, and the inverter 2 controls the supply current to the drive motor 1 based on the motor torque command value and the torque response. The road gradient can be estimated without using it, and accurate driving support can be performed.

  (2) When the brake depression amount is equal to or greater than the first brake depression amount and the brake OFF operation response speed is equal to or greater than the first operation response speed, it is estimated that the road is an uphill road and the first torque response is selected. When the brake depression amount is equal to or greater than the first brake depression amount and the brake OFF operation response speed is equal to or less than the second operation response speed that is smaller than the first operation response speed, the first torque is estimated as a downhill road. If the second torque response smaller than the response is selected, the brake depression amount is smaller than the first brake depression amount, and the brake OFF operation response speed is smaller than the first operation response speed and larger than the second operation response speed, the road is flat. Since it is assumed that there is a third torque response that is smaller than the second torque response, it is possible not only to estimate the road gradient without using a gradient sensor, Rolling easily as severely torque assist beginners, will be selected torque response as a torque assist more advanced decreases, it is possible to torque the auxiliary in accordance with the operating skill level as a result.

  (3) The controller 4 sequentially updates the maximum value of the brake depression amount after the brake is turned on, and starts when the brake is turned on and ends when a predetermined time elapses after the accelerator is turned on after the brake is turned on. When the maximum brake depression amount during the period is detected as the brake depression amount, the brake is once turned off after the brake is turned on and the brake is turned on again, or when a predetermined time has elapsed since the accelerator was turned on after the brake was turned on. Since the maximum value of the brake depression amount is reset to zero, it is possible to determine whether or not the road is flat without being affected by the adjustment of the depression amount performed by the driver during the brake operation.

  (4) Because the brake OFF operation response speed, which is the brake operation speed in the brake OFF direction from the brake ON state, is detected as the operation system response speed, an irregular situation occurs where the brake is strongly depressed for the convenience of driving conditions. Even so, the road gradient can be accurately determined according to the subsequent brake operation response speed.

  (5) The controller 4 sequentially calculates the brake OFF operation response speed. If the brake OFF operation response speed is negative, the controller 4 holds the previous calculation value. After the brake is turned ON, the brake is temporarily turned OFF and the brake is turned ON again. If the specified time has elapsed since the accelerator was turned on after the brake was turned on, the brake OFF operation response speed is reset to zero. For example, when running on a congested road with only creep torque, or on a downhill road Even when the vehicle speed is controlled only by the brake operation, the road gradient can be determined according to the brake operation immediately before the stop.

  A second embodiment will be described.

  In this embodiment, the system configuration and the control logic of the drive motor 1 are basically the same as those in the first embodiment. However, the driver operation response speed calculation calculated in step S2002 in the flowchart of FIG. 12 is different, and accordingly, the torque response determination in step S2006 is also different. In the present embodiment, a pedal switching speed from the brake OFF to the accelerator ON (hereinafter referred to as a brake / accelerator operation transition response speed) is used as the driver operation response speed. The stepping speed is obtained by dividing the distance between the accelerator pedal 5 and the brake pedal 6 by the time from when the brake pedal 6 is turned off until the accelerator pedal 5 is turned on. That is, in the present embodiment, a counter is provided that measures the time required for the pedal switching operation (operation transition time).

  FIG. 16 is a flowchart of the driver operation response speed calculation executed in this embodiment.

  Step S2401 is the same as step S2101 in FIG.

  In step S2402, it is determined whether or not the current detected value of the brake depression amount is zero. If zero, the process proceeds to step S2403; otherwise, the process proceeds to step S2404.

  In step S2403, a brake / accelerator operation transition response speed is calculated by executing a subroutine to be described later, and the process ends.

  In step S2404, the brake / accelerator operation transition response speed maximum value is held, and the process ends. Note that the maximum value here is the response speed when a general driver changes the distance from the brake pedal 6 to the accelerator pedal 5 actually measured by the vehicle at the fastest speed. That is, it is the maximum changeover operation speed possible for a general driver.

  FIG. 17 is a flowchart for the brake / accelerator operation transition response speed calculation executed in step S2403 of FIG.

  In step S2501, the accelerator ON / OFF state is detected from the detection value of the accelerator switch sensor 7.

  In step S2502, it is determined whether or not the accelerator is on. If the accelerator is on, the process proceeds to step S2503. If the accelerator is off, the process proceeds to step S2505.

  In step S2503, the brake / accelerator operation transition response speed is calculated by dividing the distance between the accelerator pedal 5 and the brake pedal 7 by the value of the transition time counter.

  In step S2504, the value of the transition time counter is reset to zero and the process ends.

  On the other hand, in step S2505, the maximum value of the brake / accelerator operation transition response speed is held.

  In step S2506, the transition time counter is incremented and the process ends.

  When the driver depresses both the accelerator pedal 5 and the brake pedal 6 at the same time, the brake / accelerator operation transition response speed is not calculated in step S2503 in FIG. / The maximum value of accelerator operation transition response speed.

  FIG. 8 is a time chart showing a change in the brake / accelerator operation transition response speed when the control of FIG. 16 is executed. The horizontal axis of the chart indicates one calculation cycle of the controller 4.

  Before time t1, since the brake depression amount is zero, the brake / accelerator operation transition response speed is maintained at the maximum value. Here, since the accelerator switch has not been turned ON after the brake depression amount becomes zero, the operation is not shifted. Therefore, the brake / accelerator operation transition response speed is zero.

  When the brake pedal 6 is depressed at time t1, the brake / accelerator operation transition response speed becomes a predetermined maximum value. Thereafter, the brake depression amount changes at times t2 and t3, but since the brake depression amount is greater than zero, the brake / accelerator operation transition response speed is held at the maximum value. Although the maximum value is held here, the present invention is not limited to this, and any value that is larger than the first operating system response speed described later may be used.

When the brake depression amount becomes zero at time t4, the brake / accelerator operation transition time is incremented (every controller 1 calculation cycle) until the next accelerator is turned on. As a result, the brake / accelerator operation transition response speed is decremented. The brake / accelerator operation transition response speed is temporarily reduced. However, it is reset to the maximum value when the brake depression amount increases thereafter.
Since the accelerator switch is OFF, the maximum value is kept.

  When the brake depression amount becomes zero at time t5 and the aquacel switch is turned on at time t6, the brake / accelerator operation transition response time is changed by the calculation in step S2504, and at time t7, a predetermined time has passed since the accelerator switch is turned on. Reset to.

  FIG. 11 is a diagram showing a transition time calculation method of the brake / accelerator operation transition response time counter. Note that one scale on the vertical axis and the horizontal axis in FIG. 11 represents one calculation cycle of the controller 4.

  When the brake depression amount becomes zero at time t0, the counter starts incrementing. When the accelerator switch is turned on at time t1, the counter is reset to zero.

  Next, a method for determining a torque response in step S2006 will be described.

  FIG. 9 is a map for determining a torque response according to this embodiment. The vertical axis represents the brake / accelerator operation transition response speed [mm / sec], and the horizontal axis represents the brake depression amount [mm].

  When the brake depression amount is equal to or greater than the first brake depression amount and the brake / accelerator operation transition response speed is equal to or greater than the first operation response speed, the first torque response is selected. When the brake depression amount is equal to or greater than the first brake depression amount and the brake / accelerator operation transition response speed is equal to or less than the second operation response speed, the second torque response is selected. Other than the region where the first torque response or the second torque response is selected, that is, when the brake depression amount is equal to or less than the first brake depression amount, and the brake depression amount is equal to or greater than the first brake depression amount, and the brake / accelerator operation transition response speed. Is less than the first operation response speed and greater than the second operation response speed, the third torque response is selected.

  About the 1st brake depression amount, it is the same as that of 1st Embodiment.

  The first operation response speed is a boundary value between a brake / accelerator operation transition response speed on an uphill road and a brake / accelerator operation transition response speed on a flat road. On an uphill road, since the speed drop after the brake depression amount becomes zero is faster than that on a flat road, the response speed of the brake / accelerator operation transition tends to be faster than that on a flat road. Thus, it can be determined whether the current position of the vehicle is an uphill road or a flat road.

  The second operation response speed is a boundary value between a brake / accelerator operation transition response speed on a downhill road and a brake / accelerator operation transition response speed on a flat road. On downhill roads, when the brake depression amount becomes zero, the vehicle accelerates due to the action of gravity, so the time from depression of the brake to depression of the accelerator pedal 5 tends to be longer than on a flat road. As this boundary value, a value obtained through an experiment or the like in advance is used.

  FIG. 10 is a time chart showing torque command values for the drive motor 1. Brake operation, brake / accelerator operation transition response speed, and accelerator switch ON / OFF are the same as in FIG. Further, the maximum brake depression amount is calculated by the same method as in the first embodiment.

  When the brake depression amount becomes zero at time t1 and the accelerator switch is turned on at time t2, the torque response is determined. Here, since the maximum brake depression amount is larger than the first brake depression amount and the brake / accelerator operation transition response speed is larger than the first operation response speed, the first torque response is selected. For comparison, the inside of the field where the second and third torque responses are selected is indicated by a broken line.

  As described above, in the present embodiment, in addition to the same effects as in the first embodiment, the following effects can be obtained.

  (1) Since the brake / accelerator operation transition response speed, which is the response speed from when the brake is turned off to when the accelerator is turned on, is detected as the operation system response speed, it is irregular that the brake is stepped on strongly for the convenience of driving conditions. Even if the situation occurs, the road gradient can be accurately determined according to the subsequent brake operation response speed.

  (2) The brake / accelerator operation transition response speed when the accelerator is ON is held until a predetermined time has elapsed from when the accelerator is turned on after the brake is turned OFF, and is reset to zero after a predetermined time. The brake / accelerator operation transition response speed is regarded as a predetermined value that is equal to or greater than the first operation response speed. For example, when driving on a congested road with only creep torque, or when the vehicle speed is controlled only by braking on a downhill road. The road gradient can be determined according to the brake operation immediately before stopping.

  (3) If the accelerator is ON while the brake is ON, the brake / accelerator operation transition response speed is regarded as a predetermined value that is equal to or higher than the first operation response speed. However, even in a situation where the accelerator pedal 5 is depressed to prevent the vehicle from moving backward, it is possible to determine the road gradient. By determining the torque response based on the result, it is possible to provide accurate driving support.

  The present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made within the scope of the technical idea described in the claims.

It is a block diagram of the system to which this embodiment is applied. It is a control block diagram which shows the basic composition of motor control. It is a figure for demonstrating the brake depression amount maximum value calculation method. It is a figure for demonstrating the accelerator ON duration calculation method. It is a figure for demonstrating the brake OFF operation response speed calculation method. It is a figure which shows the relationship between a brake depression amount, brake OFF operation response speed, and a torque response. It is a figure which shows the relationship between a brake depression amount, a brake OFF operation response speed, and a torque command value. It is a figure for demonstrating the brake / accelerator operation transfer response speed calculation method. It is a figure which shows the relationship between a brake depression amount, a brake / accelerator operation transition response speed, and a torque response. It is a figure which shows the relationship between the brake depression amount maximum value, a brake / accelerator operation transition response speed, and a torque command value. It is a figure for demonstrating the brake / accelerator operation transfer response speed calculation method. It is a main flowchart of motor control. It is a flowchart of brake depression amount calculation. It is a flowchart of a brake OFF operation response speed calculation. It is a flowchart of an accelerator ON duration calculation. It is a flowchart (the 1) of a brake / accelerator operation transfer response speed calculation. It is a flowchart (the 2) of a brake / accelerator operation transfer response speed calculation.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive motor 2 Inverter 3 Power source 4 Controller 5 Accelerator pedal 6 Brake pedal 7 Accelerator switch sensor 8 Brake depression sensor

Claims (12)

A drive motor for driving the vehicle;
An accelerator operation detecting means for detecting the driver's accelerator operation;
Brake operation detection means for detecting the driver's brake operation;
Motor torque adjusting means for controlling a supply current to the drive motor;
Torque command value calculating means for calculating a torque command value to the drive motor based on the accelerator operation;
A brake depression amount calculation means for calculating a brake depression amount based on a detection value of the brake operation detection means;
An operation system response speed calculation unit that calculates a response speed of the driver to the operation system based on a detection value of at least one of the accelerator operation detection unit and the brake operation detection unit;
A gradient estimating means for estimating a road gradient of the current vehicle position based on the brake depression amount and the operation system response speed;
Torque response determining means for determining a torque response of the drive motor according to a road gradient when the vehicle starts,
With
The motor torque adjusting means controls a supply current to the drive motor based on the motor torque command value and the torque response,
The gradient estimation means estimates that the slope is an uphill road when the brake depression amount is equal to or greater than a predetermined threshold and the operation system response speed is equal to or greater than a predetermined first threshold, and the brake depression amount is predetermined. When the operating system response speed is equal to or less than a second threshold value smaller than a predetermined first threshold value, it is estimated that the road is a downhill road, and when the brake depression amount is smaller than the predetermined threshold value, and a motor control device, characterized in that estimated to be flat road when the brake depression amount is larger than the predetermined threshold value or more and the operating system response speed is smaller than the first threshold and the second threshold value.   The torque response determining means selects a first torque response when the slope estimating means estimates an uphill road, and selects a second torque response smaller than the first torque response when estimating a flat road. The motor control device according to claim 1, wherein a third torque response smaller than the second torque response is selected when the downhill road is estimated.   The brake depression amount calculation means sequentially updates the maximum value of the brake depression amount after the brake is turned on, and when the brake is turned on, the start time, and when the predetermined time elapses after the brake is turned on, the last time 3. The motor control device according to claim 1, wherein a maximum value of a brake depression amount during a period to be detected is detected as the brake depression amount.   The brake depressing amount calculating means calculates the brake depressing amount that is sequentially updated when the brake is once turned off after the brake is turned on and the brake is turned on again or when a predetermined time elapses after the accelerator is turned on after the brake is turned on. The motor control device according to claim 3, wherein the maximum value is reset to zero.   5. The operation system response speed calculating means detects a brake OFF operation response speed, which is a brake operation speed in a brake OFF direction from a brake ON state, as the operation system response speed. The motor control apparatus as described in any one.   6. The motor according to claim 5, wherein the operation system response speed calculation means sequentially calculates the brake OFF operation response speed, and retains a previous calculation value when the brake OFF operation response speed is negative. Control device.   The operation system response speed calculation means is configured to turn off the brake OFF operation response speed when the brake is temporarily turned OFF after the brake is turned ON and the brake is turned ON again, or when a predetermined time has elapsed from the accelerator ON after the brake is turned ON. The motor control device according to claim 6, wherein the motor control device is reset to zero. A creep torque limiting means for limiting the creep torque when the brake is on is provided.
The motor control apparatus according to claim 1, wherein the torque response determining unit determines a response of the creep torque.   The operation system response speed calculating means detects a brake / accelerator operation transition response speed, which is a response speed from when the brake is turned off to when the accelerator is turned on, as the operation system response speed. The motor control device according to any one of 4.   The operation system response speed calculation means holds the brake / accelerator operation transition response speed when the accelerator is ON until a predetermined time elapses after the accelerator is turned ON after the brake is turned OFF, and resets to zero after the predetermined time. The motor control device according to claim 9.   11. The motor control device according to claim 9, wherein the operation system response speed calculation unit regards the brake / accelerator operation transition response speed as a predetermined value equal to or higher than the first threshold when the brake is on.   The operation system response speed calculation means regards the brake / accelerator operation transition response speed as a predetermined value equal to or higher than the first threshold when the accelerator is ON in a brake-on state. The motor control device according to any one of 11 to 11.

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