JP6111516B2 - Electric vehicle motor control device - Google Patents

Description

  The present invention relates to a motor control device for an electric vehicle, and more particularly to an apparatus for realizing drive control for preventing damage to an electric motor mounted as a drive source.

  In an electric vehicle that travels using an electric motor as a drive source, such as a hybrid vehicle or an electric vehicle, the output torque of the electric motor can be stopped in the middle of a slope by balancing the output torque of the electric motor with a driving force required for climbing. At this time, a so-called motor lock occurs in which the rotation drive of the electric motor is stopped while the energization of supplying electric power to the electric motor is maintained by converting the DC power in the storage battery into AC power via the inverter circuit. Will do. In a vehicle equipped with an electric motor, if such a motor lock state is maintained, there is a possibility that problems such as damage to the switching elements of the inverter circuit due to continued energization may occur.

  Therefore, in this type of electric vehicle motor control device, when detecting the occurrence of a motor lock state of the electric motor, the output torque is reduced more than the driving force required for climbing, thereby moving the vehicle backward. It has been proposed to execute control processing for rotating the rotating shaft of the electric motor (for example, Patent Documents 1 and 2). In this case, the energization phase in the electric motor can be switched to avoid continuous energization to the same switching element, and the driver who notices that the vehicle is moving backward is encouraged to switch from the accelerator pedal to the brake pedal. The continuous energization of the electric motor can be terminated.

JP 11-215687 A JP 2008-301547 A

  However, in such a motor control device for an electric vehicle, the driver does not notice the reverse of the vehicle, for example, by concentrating on the conversation with the passenger, so that the accelerator pedal is not switched to the brake pedal. It may not be.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a motor control device for an electric vehicle capable of avoiding damage to the electric motor due to the motor lock while ensuring safety.

The first aspect of the invention according to the motor controller of an electric vehicle for solving the aforementioned problems is a motor control device mounted on the vehicle with an electric motor functioning as a driving source for driving the vehicle, the electric motor An abnormality determination unit that determines whether or not an abnormality has occurred, an angle detection unit that detects a rotation angle of the electric motor, and the angle detection unit that detects when the electric motor outputs a driving force An abnormality has occurred in the electric motor by a lock detection unit that detects that the electric motor is in a locked state based on a rotation angle of the electric motor after a predetermined time has elapsed from a reference time to be operated, and the abnormality determination unit. If it is determined that there is no lock and the lock detection unit detects the lock state of the electric motor, the vehicle is moved in the forward direction or the reverse direction, and then the angle is detected. When There it detects the rotation of the electric motor of the angle that has been set in advance, the reverse direction or the backward direction to adjust the output torque of the electric motor so as to move in the opposite direction to the said forward direction And a torque control unit.

According to a second aspect of the invention relating to the motor control device for an electric vehicle that solves the above-described problem, in addition to the specific matter of the first aspect, the abnormality determination unit includes: a coil temperature of the electric motor; Whether or not an abnormality has occurred in the electric motor is determined based on at least one of input power and actual torque output from the electric motor.

According to a third aspect of the invention relating to the motor control device for an electric vehicle that solves the above problem, in addition to the specific matter of the first or second aspect, the electric motor is fixed by energizing a coil of a plurality of phases. the rotor in the child are configured to drive rotation, wherein the torque control section, an angle at least one phase or more rotation angle switches the move in the forward direction or the backward direction of the vehicle of the electric motor It is characterized by being set as.

In a fourth aspect of the invention relating to a motor control device for an electric vehicle that solves the above problem, in addition to any one of the first to third specific items, the angle detection unit is a stator of the electric motor. And a detection coil disposed on the rotor side, and an excitation coil disposed on the rotor side of the electric motor, wherein the rotational position is detected based on an electromotive force generated in the excitation coil on the rotor side. To do.

According to a fifth aspect of the invention of a motor control device for an electric vehicle that solves the above problem, in addition to the specific matter of any one of the first to fourth aspects, the torque control unit may The adjustment amount of the output torque after the start of the adjustment of the output torque when the vehicle is moved in the reverse direction is gradually changed so that the adjustment output torque smoothly continues.

A sixth aspect of the invention according to the motor controller of an electric vehicle to solve the above problems, in addition to the specific matters of the fifth embodiment, the torque control unit, the adjustment amount of the output torque of the electric motor, the output Adjustment that is set in advance according to the elapsed time from the start of the adjustment process that gradually changes the torque adjustment amount or the judgment process that releases the adjustment control that gradually changes the adjustment amount of the output torque It is characterized in that it is determined by searching from a map.

  According to a seventh aspect of the invention of the motor control device for an electric vehicle that solves the above-mentioned problem, in addition to the specific matter of any one of the first to sixth aspects, the torque control unit performs an accelerator pedal non-depressing operation. Alternatively, the adjustment control of the output torque of the electric motor is canceled based on the sensor information that detects the depression of the brake pedal.

  An eighth aspect of the invention relating to the motor control device for an electric vehicle that solves the above-described problems is that in addition to the specific matter of any one of the first to seventh aspects, an obstacle that exists in the traveling direction of the vehicle. An obstacle detection unit for detecting presence / absence is provided, and the torque control unit executes adjustment control of the output torque of the electric motor when no obstacle in the traveling direction is detected by the obstacle detection unit. It is characterized by.

  In a ninth aspect of the invention relating to the motor control device for an electric vehicle that solves the above problem, in addition to the specific matter of the eighth aspect, the torque control unit is configured such that the obstacle detection unit detects an obstacle. The adjustment control of the output torque of the electric motor in a non-traveling direction is continued.

As described above, according to the first and second aspects of the present invention, when the lock state of the electric motor that maintains the vehicle in a stopped state is detected on a slope or the like, the output torque of the electric motor is adjusted. Since the vehicle is moved in a short distance in the forward direction and the reverse direction, it is possible to avoid the state in which the drive shaft of the electric motor has stopped rotating. Therefore, it is possible to prevent the energized phase of the electric motor from being fixed, and to prevent damage due to continuous energization to the same switching element by switching the energized phase at each of forward and backward movements. In addition, it is possible to minimize the possibility that the movement of only one direction forward or backward continues and collides with an obstacle such as another vehicle. In addition, the driver can be more actively aware that the electric motor is in a locked state than when moving forward or backward in only one direction, and the switch from the accelerator pedal to the brake pedal is surely urged. be able to.

According to the first and second aspects of the present invention, since the rotation angle of the electric motor (drive shaft) is detected, the output torque is increased or decreased so that the vehicle is moved a short distance in the forward direction and the reverse direction. The amount of movement of the vehicle (advancing amount or reversing amount) can be set arbitrarily. Therefore, it can be effectively noticed by increasing the amount of movement to greatly change the scenery that enters the eye, or by repeatedly experiencing a small amount of movement and switching the moving direction at a high frequency.

  According to the third aspect of the present invention, since the short-distance movement of the vehicle in the forward or backward direction is switched at a rotation angle of one phase or more of the electric motor, the movement direction can be switched at an extremely short distance. it can. Therefore, damage to the electric motor can be prevented more safely.

  According to the fourth aspect of the present invention, since the rotation of the electric motor is detected by the electromotive force of the exciting coil, the rotation of the rotor can be detected with high reliability. Therefore, the output torque of the electric motor can be controlled with high accuracy.

  According to the fifth aspect of the present invention, since the output torque of the electric motor is smoothly continued to switch between forward and backward movement of the vehicle, it is possible to prevent the vehicle moving direction and magnitude from being greatly changed. can do. Accordingly, it is possible to avoid abruptly changing the movement of the vehicle, and to prevent the driver from feeling uncomfortable such as being surprised.

  According to the sixth aspect of the present invention, since the output torque of the electric motor is adjusted by the numerical value of the adjustment map that has been set according to the elapsed time, the torque adjustment rate (decrease rate or increase rate) is calculated. Doing so can be eliminated, and the output torque can be adjusted with simple control. Therefore, it is possible to avoid erroneous control due to sensor detection errors or calculation errors due to noise, etc., and to perform adjustment control of the electric motor with high reliability, resulting in unpleasant output torque adjustment results. It can be avoided.

  According to the seventh aspect of the present invention, when the depression of the accelerator pedal is canceled or the brake pedal is depressed, the adjustment control of the output torque of the electric motor is released, so that the driver's operation is directly performed. Immediately after being sensed, energization of the electric motor can be terminated. Therefore, when starting again, energization control to the electric motor can be started anew so that sufficient torque is generated.

  According to the eighth aspect of the present invention, since the adjustment control of the output torque of the electric motor is executed when there is no obstacle in the traveling direction of the vehicle, the vehicle is moved in the traveling direction with the obstacle. The collision can be avoided in advance. Therefore, the safety of the control process for avoiding the locked state of the electric motor can be enhanced.

  According to the ninth aspect of the present invention, the output torque of the electric motor is adjusted so as to go in the forward direction or the backward direction of the vehicle where there is no obstacle, so the vehicle is moved in the forward direction without the obstacle. be able to. Therefore, the electric motor can be removed from the locked state while avoiding the vehicle from colliding with the obstacle.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the motor control apparatus of the electric vehicle which concerns on this invention, and is a conceptual block diagram which shows schematic structure of the electric vehicle for demonstrating the application location. It is a block diagram which shows the principal part structure. It is a flowchart which shows the whole flow of the countermeasure control process of the motor lock. It is a flowchart which shows the motor abnormality determination process in the motor lock countermeasure control process. It is a flowchart which shows the motor lock determination process in the motor lock countermeasure control process. It is a flowchart which shows the reverse destination state determination process in the motor lock countermeasure control process. It is a flowchart which shows the advance destination state determination process in the motor lock countermeasure control process. It is a flowchart which shows the torque suppression control process in the motor lock countermeasure control process. It is a list which shows the table map used by the torque suppression control. It is a graph which illustrates the relationship between the output torque according to an accelerator opening, and a motor rotation speed utilized by the torque suppression control. It is a flowchart which shows the torque increase control process in the motor lock countermeasure control process. It is a list which shows the table map used by the torque increase control. It is a flowchart which shows the torque control return process in the motor lock countermeasure control process. It is a flowchart which shows the torque control cancellation | release determination process in the motor lock countermeasure control process. It is a figure which shows 2nd Embodiment of the motor control apparatus of the electric vehicle which concerns on this invention, and is a flowchart which shows the whole flow of the countermeasure control process of the motor lock.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIGS. 1-14 is a figure which shows 1st Embodiment of the motor control apparatus of the electric vehicle which concerns on this invention.

  In FIG. 1, an electric vehicle 10 rolls drive wheels 13 by supplying electric energy in a high-voltage battery (storage battery) 11 to an electric motor 12 via a power cable D and rotating a drive shaft 12a. Built to travel. The electric vehicle 10 achieves traveling by using an electric motor 12 as a drive source and an ECU (Electronic Control Unit) 20 that acquires information from various sensors and the like that are arranged in each unit and performs overall control. ECU20 is connected to each part including the electric motor 12 side via various signal cables d, and acquires various information.

  As shown in FIG. 2, the ECU 20 executes a control program stored in the storage device 15 to drive and control the electric motor 12 based on various parameters. For example, the drive wheel 13 is driven to rotate. As an output request for torque of the electric motor 12, the accelerator opening corresponding to the amount of depression of the accelerator pedal by the driver (driver) is received from the accelerator opening sensor 16, and the traveling speed of the electric vehicle 10 is received from the vehicle speed sensor 17. Then, the electric motor 12 is supplied with an amount of power that meets the output request. The ECU 20 controls the braking mechanism (not shown) according to a detection signal from a brake switch (SW) 18 that detects the depression of the brake pedal, thereby braking the rotation of the driving wheel 13 and stopping the electric vehicle 10. Then, control processing such as causing the electric motor 12 to function as a generator and storing regenerative energy in the battery 11 is also executed. The ECU 20 also has a warning unit 19 for notifying the occurrence of an abnormality by turning on / flashing a warning light or the like prepared on an instrument panel (not shown) when the occurrence of an abnormality in each part of the vehicle such as the electric motor 12 is detected. It is connected.

  The ECU 20 has a motor rotation composed of a rotation angle sensor for detecting the rotation angle of the electric motor 12 in order to acquire and collect various information necessary for controlling the driving of the electric motor 12 as a countermeasure against motor lock on the slope. An angle detection device (angle detection unit) 21, a torque detection device 22 that calculates (detects) the output torque of the electric motor 12 based on the power supplied to the electric motor 12, and a temperature rise when the electric motor 12 is driven A coil temperature detector 23 for detecting the coil temperature for management, a confirmation timer 24 for measuring an elapsed time for confirming whether or not the electric motor 12 is locked, and a motor lock measure for the electric motor 12 An adjustment timer 25 for measuring the elapsed time taken into account when adjusting the torque control as the control processing of the electric vehicle 10, An obstacle detection device 26 for detecting an obstacle such as other vehicles existing in a square and behind the setting within a distance, are connected prepared. As the motor rotation angle detection device 21, for example, a detection coil is attached to the stator side of the electric motor 12, and an excitation coil is attached to the rotor side integral with the drive shaft 12a, thereby rotating the drive shaft 12a. A so-called resolver type that can detect the rotation angle of the drive shaft 12a with a voltage (electromotive force) generated in the exciting coil according to the angle is employed. Further, as the obstacle detection device 26, for example, a sensor type that detects a separation distance to the obstacle by reflection of ultrasonic waves, infrared rays, or the like emitted in the traveling direction is used. For example, an acquired image by a stereo camera is used. Needless to say, detection principles other than these may be employed, such as detecting the separation distance to the obstacle.

  Further, the ECU 20 continues and maintains a state where the electric motor 12 is substantially stopped from rotating while the electric motor 12 is supplied with power, so that countermeasure control for eliminating the so-called motor lock state is performed. A control program for executing the processing is prepared for storage in the storage device 15 and prevents the electric motor 12 including the inverter circuit for supplying power from being damaged due to the continuation of the motor lock state. It is like that. The ECU 20 controls the drive of the electric motor 12 based on the acquired information received from each of the units in accordance with a control program for executing the motor lock countermeasure control process, whereby a motor abnormality determination unit 20A, a motor lock determination unit ( Lock detection unit) 20B, traveling direction state determination unit (obstacle detection unit) 20C, torque suppression control unit (torque control unit) 20D, torque increase control unit (torque control unit) 20E, torque control release determination unit 20F, torque control It functions as the return unit 20G.

  Specifically, the motor lock countermeasure control process when the drive gear or the back gear is selected and the vehicle moves forward in the uphill direction will be described. As shown in the flowchart of FIG. 3, the ECU 20 detects the vehicle speed sensor 17. When it is confirmed from the information that the electric vehicle 10 is almost stopped (vehicle speed ≈ 0 km / hour) (step S11), a process described later for determining whether or not an abnormality has occurred in the electric motor 12 was executed. Later (step S12), if the determination result indicates that a motor abnormality has occurred (Fs = 1), the motor lock countermeasure control process ends as it is, while the determination result that a motor abnormality has not occurred ( If Fs = 0), the process proceeds to the next step S14 (step S13). In the present embodiment, the vehicle speed ≈ 0 km / hour is set as a determination criterion based on the almost stopped state. However, the present invention is not limited to this, and a motor that may be damaged due to energization of the same energization coil of the electric motor 12 may be used. What is necessary is just to set the vehicle speed which should be judged as a locked state, for example, you may set vehicle speed ≒ 5km / hour.

  As a result, it is possible to avoid continuing unstable driving despite the occurrence of an abnormality such as disconnection or overheating in the electric motor 12, and the warning unit 19 warns of the occurrence of the abnormality. It is possible to prompt the user to take appropriate measures by informing through a lamp or the like.

  After this, after executing a process to be described later for determining whether or not the motor lock has occurred in the electric motor 12 (step S14), the determination result (Ft = 0) that the motor lock has not occurred. In some cases, the motor lock countermeasure control process is terminated as it is, whereas in the case of a determination result (Ft = 1) that the motor lock has occurred, the process proceeds to the next step S16 (step S15). It should be noted that the confirmation of the occurrence of motor lock in step S14 and step S26 described later is constructed so as to be repeated even during the same routine as will be described later, so that the presence or absence of occurrence is always confirmed. ing. Further, since the vehicle stop state in step S11 is also repeatedly confirmed, it goes without saying that the motor lock may be constructed so as to be skipped until it is determined in step S23 described later that the torque control can be released.

  Next, in executing a process for controlling countermeasures against the substantial motor lock generated in the electric motor 12, first, a process to be described later for determining the presence or absence of an obstacle at the retreat destination in the descending direction is executed (step S16). If the determination result (Fb = 1) indicates that there is an obstacle at the retreat destination, the motor lock countermeasure control process is finished as it is, while the determination result (Fs = No) exists at the retreat destination. In the case of 0), the process proceeds to the next step S18 (step S17).

  Next, when it is confirmed in the previous step S17 that there is no obstacle in the reverse direction, “1” is stored in the flag Ms, “0” is stored in the flag Mt, and torque for moving forward in the uphill direction is output. Then, a process to be described later is performed to suppress the output torque of the electric motor 12 that is substantially in a stopped state (step S18).

  As a result, the electric vehicle 10 is gradually retracted in a downward direction from a state where it is substantially stopped while climbing the hill, thereby switching the energization coil of the rotor (rotor) together with the drive shaft 12a of the electric motor 12. Can be rotated.

  Next, the rotation angle θ (rad) of the rotor is acquired from the detection value output from the motor rotation angle detection device 21 built in the electric motor 12 (step S19), and the rotation angle θ is set in the storage device 15 in advance. It is confirmed whether or not the angle, for example, the rotation angle of at least one phase exceeds 120 ° at which the energized phase to the rotor coil of the three-phase electric motor 12 is switched (step S20). The rotation angle θ is not limited to the rotation angle of 120 ° for one phase in the case of three phases, and the angle of one or more phases in a plurality of phases may be set arbitrarily.

  In step S20, when it is confirmed that the rotation angle θ of the rotor of the electric motor 12 is equal to or smaller than the set angle and the rotation amount of the drive shaft 12a is insufficient, the process proceeds to step S21 and the motor lock countermeasure control process is continued. .

  In step S20, when it is confirmed that the rotation angle θ of the rotor of the electric motor 12 exceeds the set angle and the drive shaft 12a has sufficiently rotated, the electric motor 12 is returned to a steady torque output. Subsequent to executing the process described later (step S22), a process described later for determining whether or not a condition for canceling the control of the output torque of the electric motor 12 executed in the motor lock countermeasure control process is executed. (Step S23), it is confirmed whether or not the torque control release condition is satisfied (Step S24). If the determination result (Fr = 0) indicates that the torque control release condition is not satisfied, In the case of determination result (Fr = 1) that the torque control release condition is satisfied while proceeding to step S25 and continuing the motor lock countermeasure control process , To terminate the measures control processing of the motor lock.

  Thereby, after confirming whether there is an obstacle in the backward retreat destination from the state where the electric vehicle 10 is substantially stopped on the way uphill, the electric vehicle 12 is gradually retreated and the energization coil of the electric motor 12 is moved. The switch can be switched, and the short-distance movement can be repeated so as to prevent the inverter element for power supply of the electric motor 12 from being damaged while avoiding the collision with the obstacle.

  In step S21, since it is confirmed that the rotation amount of the drive shaft 12a is insufficient in step S20, it is confirmed whether or not torque suppression control is being executed as the current motor lock countermeasure control processing. When the suppression control is being executed, the process proceeds to step S14 (returns), and whether or not the motor lock is generated, and after confirming the reverse destination, the output torque suppression control of the electric motor 12 (reverse of the vehicle in the downward direction). Continue. In step S21, if the current motor lock countermeasure control process is not executing torque suppression control but executing torque increase control (to be described later), the process proceeds to step S26 (to be described later). After the confirmation of the advance destination together with the presence or absence of, the increase control of the output torque of the electric motor 12 (advance in the uphill direction of the vehicle) is continued.

  In step S25, since it is confirmed in step S24 that the torque control release condition for the electric motor 12 is not satisfied, it is determined whether torque suppression control has been executed as a countermeasure control process for the immediately preceding motor lock. If the torque suppression control has been executed, the process proceeds to step S26, and the torque increase control is executed after confirming the forward movement destination, which will be described later, together with the presence or absence of the motor lock in place of the immediately preceding torque suppression control. On the other hand, if the executed torque control is not the torque suppression control, the process proceeds to step S14, and the suppression control of the output torque of the electric motor 12 is executed after confirming the reverse destination together with the presence or absence of the motor lock.

  In step S26 and subsequent steps, in steps S21 and S25, it is selected to execute increase control of the output torque of the electric motor 12 (advance in the uphill direction of the vehicle) after confirming the advance destination together with the presence or absence of motor lock. Therefore, similarly to the case where the control for suppressing the output torque of the electric motor 12 is executed, the process described later for determining whether or not the motor lock has occurred in the electric motor 12 is executed again (step S26). If the determination result indicates that the motor lock has not occurred (Ft = 0), the motor lock countermeasure control process is terminated as it is, and the determination result that the motor lock has occurred (Ft = 1). In this case, the process proceeds to the next step S28 (step S27).

  Next, in executing the increase control of the output torque of the electric motor 12 as a countermeasure control process for the motor lock generated in the electric motor 12, first, a process to be described later for determining the presence or absence of an obstacle in the uphill destination is first performed. After execution (step S28), if the determination result indicates that there is an obstacle ahead (Ff = 1), the process advances to step S16 to continue the motor lock countermeasure control process, and the reverse destination On the other hand, if it is determined that there is no obstacle ahead (Ff = 0), the process proceeds to the next step S30 (step S29).

  Next, when it is confirmed in the previous step S29 that there is no obstacle ahead, the flag Ms stores “0”, the flag Mt stores “1”, and outputs the torque for moving forward in the uphill direction. A process to be described later for increasing the output torque of the electric motor 12 is executed (step S30).

  As a result, the electric vehicle 10 is gradually retracted in the downward direction from the state where it is substantially stopped during the climbing, and conversely, it is confirmed whether there is an obstacle in the advance destination in the climbing direction. The electric motor 12 can be reversely rotated so that the energizing coil is switched by gradually moving forward in the uphill direction. If there is an obstacle ahead in the uphill direction, it is switched again to the control for suppressing the output torque of the electric motor 12 (reverse of the vehicle in the downward direction) after confirming the reverse destination. It is possible to prevent the electric motor 12 from being damaged by continuing the countermeasure control process.

  Then, as shown in the flowchart of FIG. 4, the motor abnormality determination unit 20A (ECU 20) determines the coil temperature of the electric motor 12 detected by the coil temperature detector 23 as a motor abnormality determination process in step S12. It is confirmed whether or not the temperature is higher than a set temperature that is lower by about 30 degrees than the temperature at which damage is likely to occur (step S1201).

  If it is confirmed in step S1201 that the coil temperature of the electric motor 12 is equal to or higher than the set temperature, it is not preferable to drive the electric motor 12 by energizing it, so “1” is set in the motor abnormality determination flag Fs. Store (step S1202), and the motor abnormality determination process is terminated. In this case, at the same time, the warning unit 19 is lit or blinked with a warning light or the like for notifying the corresponding abnormal state of the electric motor 12 (the same applies to the following processing).

  If it is confirmed in step S1201 that the coil temperature of the electric motor 12 is lower than the set temperature, the input power supplied to the electric motor 12 may continue to be damaged, for example. It is checked whether or not the set power is about 5 kW lower than the input power that comes out (step S1203).

In step S1203, when it is confirmed that the input power of the electric motor 12 is equal to or higher than the set power, it is not preferable to continuously drive the electric motor 12, and the process proceeds to step S1202. “1” is stored in the abnormality determination flag Fs, and the motor abnormality determination process is terminated.

  In step S1203, when it is confirmed that the input power of the electric motor 12 is less than the set power, the actual torque actually output by the electric motor 12 detected by the torque detection device 22 is, for example, Then, it is confirmed whether or not the set torque is lower by about 30 Nm than the output torque at which the motor itself may be damaged (step S1204).

In step S1204, when it is confirmed that the actual torque output from the electric motor 12 is equal to or greater than the set torque, it is not preferable to continuously drive the electric motor 12, and the process proceeds to step S1202. Then, “1” is stored in the motor abnormality determination flag Fs, and the motor abnormality determination process is terminated.

  In step S1204, only when it is confirmed that the actual torque output from the electric motor 12 is less than the set torque, the motor abnormality determination flag Fs is set so as to permit the continuation of the motor lock countermeasure control process. “0” is stored and the motor abnormality determination process is terminated.

  As a result, it is possible to prevent the electric motor 12 from continuing to supply power despite the occurrence of a malfunction in the electric motor 12, and the electric motor 12 can be prevented from other factors. It is possible to prevent damage from occurring.

Next, as shown in the flowchart of FIG. 5, the motor lock determination unit 20B (ECU 20) detects the motor rotation angle detection device 21 at the start of this determination process (reference time) as the motor lock determination process in step S14. After the rotation angle of the rotor of the electric motor 12 is set to the reference angle A (step S1401), the confirmation timer 24 for confirming whether or not the lock has occurred is activated after resetting to start counting elapsed time Tr (step S1402). .

  Next, after confirming that the elapsed time Tr counted by the confirmation timer 24 has exceeded 10 seconds (step S1403), the rotational angle from the reference angle A of the rotor of the electric motor 12 detected by the motor rotational angle detector 21 ( (Shift angle) B is acquired (step S1404), and the absolute value of the rotation angle B is preset, for example, the rotation angle for at least one phase at which the energization phase to the rotor coil of the electric motor 12 is switched. It is confirmed whether it is less than 120 ° (step S1405).

  In step S1405, when the rotation angle B of the electric motor 12 is equal to or larger than the set angle, the energized phase of the electric motor 12 is switched, so that the motor lock is not generated and the motor lock determination flag Ft is set. “0” is stored (step S1406), and the motor lock determination process is terminated. In step S1405, when the rotation angle B of the electric motor 12 is less than the set angle, it is determined that the motor lock has occurred because the energized phase of the electric motor 12 has not been switched, and the motor lock determination flag Ft “1” is stored in (Step S1407), and the motor lock determination processing is terminated.

  Thus, the motor lock determination unit 20B can reliably detect the occurrence of the motor lock in the electric motor 12 and start the countermeasure control process, and prevent the electric motor 12 from being damaged in advance. can do.

  Next, as shown in the flowchart of FIG. 6, the traveling direction state determination unit 20 </ b> C (ECU 20), as shown in the flowchart of FIG. Within the range, for example, the presence or absence of an obstacle is confirmed within the rear range to the extent that the electric motor 12 is rotated several times by execution of the motor lock countermeasure control process (step S1601).

  In step S1601, when it is confirmed that there is an obstacle such as another vehicle at the retreat destination within the range where the electric vehicle 10 may retreat (fall), the electric vehicle 10 is retreated as it is. Since this is not preferable, “1” is stored in the reverse destination state determination flag Fb (step S1602), and the reverse destination state determination process is terminated.

  Further, only in the case where it is confirmed in step S1601 that there is no obstacle at the retreat destination within the range where the electric vehicle 10 may retreat, the continuation of the motor lock countermeasure control process is permitted. Then, “0” is stored in the reverse destination state determination flag Fb (step S1603), and the reverse destination state determination process is ended.

  Similarly, as shown in the flowchart of FIG. 7, the traveling direction state determination unit 20 </ b> C (ECU 20) performs the obstacle within the set short distance range detected by the obstacle detection device 26 as the advance destination state determination process in step S <b> 28. The presence / absence of an object is confirmed (step S2801).

  If it is confirmed in step S2801 that there is an obstacle ahead of the range in which the electric vehicle 10 may move forward (uphill), it is not preferable to move the electric vehicle 10 forward as it is. Then, “1” is stored in the forward destination state determination flag Ff (step S2802), and this forward destination state determination process ends.

  Also, in step S2801, the continuation of the motor lock countermeasure control process is permitted only when it is confirmed that there is no obstacle at the forward destination within the range where the electric vehicle 10 may move forward. Then, “0” is stored in the advance destination state determination flag Ff (step S2803), and the advance destination state determination process ends.

  As a result, the motor lock countermeasure control process is continued as it is despite the presence of an obstacle within the range of the traveling direction in which the electric vehicle 10 is moved back and forth in the motor lock countermeasure control process. It is possible to prevent the vehicle from colliding with an obstacle such as another vehicle in the traveling direction.

  Next, as shown in the flowchart of FIG. 8, the torque suppression control unit 20D (ECU 20) first measures and holds the elapsed time Tk up to a maximum of 10 seconds as the torque suppression control process in step S18. Is started (step S1801), and the adjustment rate (decrease rate in the suppression control) Rt corresponding to the elapsed time Tk (seconds) counted by the adjustment timer 24 is retrieved from the storage device 15 and held (step S1802). . This adjustment decrease rate Rt is stored in advance in a table map (adjustment map) of the storage device 15, and as shown in FIG. 9, the table map is used for torque suppression for each natural number including “0”. The decrease rate Rt is stored and held.

  Thereby, the torque suppression control unit 20D can obtain an adjustment rate (adjustment amount) Rt according to the elapsed time Tk with high reliability by avoiding calculation errors caused by noise and the like. The control process can function effectively. For example, in the case of Tk = 0 seconds at the beginning of time measurement of the elapsed time Tk, it is avoided that the output torque is suddenly reduced by skipping the process of substantially reducing Rt = 100%, After the elapsed time Tk = 5 seconds and Rt = 75%, the decrease rate is gradually increased so that Rt = 50% after Tk = 10 seconds (the number to be multiplied is reduced), and the output torque By setting the processing for reducing the smoothness to continue smoothly, the driver is prevented from being surprised by a sudden change in the output torque. This effect is adopted so that it can be obtained similarly in the torque increase control unit 20E described later, and can also be obtained in step S1804 described later, and this motor lock countermeasure control processing can be effectively and comfortably performed. Can function.

  Next, the voltage output value of the detection information detected by the accelerator opening sensor 16 is acquired (step S1803), and the output torque according to the accelerator opening and the rotational speed of the electric motor 12 can be derived in advance in the storage device 15. Using the stored search map shown in FIG. 10, the required torque Td1 corresponding to the amount of depression (voltage output value) of the accelerator pedal operated by the driver detected by the accelerator opening sensor 16 is searched (step S1804). ).

  Here, the search map shown in FIG. 10 is prepared in order to reflect the accelerator operation operated by the driver of the electric vehicle 10 in accordance with the driving condition in the driving speed. As shown in the map, the output torque is associated with the motor rotation speed every accelerator opening 0% to 100%, and the ECU 20 responds to the accelerator pedal depression amount% corresponding to the motor rotation speed (speed). The power supply to the electric motor 12 is adjusted and controlled so as to be output. That is, in step S1804, the required torque Td1 is obtained as it is when the driver performs the accelerator operation. At this time, the electric motor 12 is substantially non-rotating. When the accelerator opening is 0%, the torque control is set so that the torque output corresponds to the creep force in the vehicle running on the internal combustion engine, and reaches a certain running speed. After that, rotational resistance is generated including the case of resistance load due to regenerative power generation.

  Next, it is confirmed whether or not the current request torque Td1 (current value) obtained in the previous step S1804 is greater than the request torque Td1 (previous value) obtained in the previous routine (step S1805). If not, the current value is adopted (step S1806), whereas if it has increased, the previous value is adopted (step S1807) and held as the required torque Td2.

  Thereby, the torque suppression control unit 20D can execute the motor lock countermeasure control process while avoiding that the torque output from the electric motor 12 substantially increases and the effect of the torque suppression control is lost. it can. Note that the current value may be used as the previous value at the start of the control process (the same applies to the previous value in the control process described below).

  Next, the required torque Td2 held in the previous step S1806 or step S1807 is multiplied by the previous adjustment decrease rate Rt to adjust the output torque Tout derived according to the driver's accelerator pedal depression amount. (Step S1808).

  As a result, the electric vehicle 10 can be gradually retracted in the downward direction when the motor lock is generated, and the driver is not surprised and the electric motor 12 is in a locked state. You can be aware of the retreat and prompt the switch to the brake pedal.

  Next, as shown in the flowchart of FIG. 11, the torque increase control unit 20E (ECU 20) starts the adjustment timer 25 as the torque increase control process in step S30, as shown in the flowchart of FIG. In step S3001, the adjustment rate (increase rate in the case of increase control) Rt corresponding to the elapsed time Tk (seconds) measured by the adjustment timer 25 is retrieved from the storage device 15 and held (step S3002). This adjustment increase rate Rt is stored in advance in a table map of the storage device 15, and as shown in FIG. 12, the increase rate Rt for increasing torque is set for each natural number including “0” in the table map. Retained.

  Next, the voltage output value of the detection information detected by the accelerator opening sensor 16 is acquired (step S3003), and the operation detected by the accelerator opening sensor 16 using the search map shown in FIG. The requested torque Td1 corresponding to the accelerator operation (voltage output value) of the person is searched (step S3004).

  After this, the output torque Tout derived in accordance with the amount of depression of the driver's accelerator pedal by multiplying the required torque Td1 held in the previous step S3004 by the previous adjustment increase rate Rt is elapsed time according to the adjustment increase rate Rt. Adjustment is made so as to increase from 100% to 150% according to Tk (seconds) (step S3005).

  Next, the current output torque Tout (current value) obtained in the previous step S3005 is added to the output torque Tout (previous value) obtained in the previous routine by the limit value Lu1 allowed in the torque increase processing per unit time. It is confirmed whether or not the value or the maximum value Lt set as the torque that can be output by the electric motor 12 is exceeded (step S3006). If not, the current value is adopted (step S3007). If either of them is exceeded, the value obtained by adding the limit value Lu1 to the previous value Tout or the smaller one of the maximum values Lt of the output torque is adopted (step S3008) and held as the output torque Tout.

  As a result, the torque increase control unit 20E can increase the output torque while avoiding the torque output from the electric motor 12 from exceeding the limit, and execute the motor lock countermeasure control process. it can.

  As a result, the electric vehicle 10 can be gradually advanced in the uphill direction when the motor lock is generated, and the driver is not surprised and the electric motor 12 is in a locked state. You can be aware of the forward movement and prompt the switch to the brake pedal.

  Next, the torque control return unit 20G (ECU 20) executes a process of adjusting the output torque Touch as opposed to the torque suppression / increase control described above as the torque control return process in step S22. When returning from the suppression control, the torque increase control is executed conversely, and when returning from the torque increase control, the torque suppression control is executed conversely. For example, the case of returning from torque suppression control will be described as an example. As shown in the flowchart of FIG. 13, the torque increase control described in FIG. 11 is executed in the same manner. The countdown of the elapsed time Tk (seconds) held is started (step S2201), and the adjustment rate (decrease rate used in the suppression control) Rt corresponding to the elapsed time Tk (seconds) that the adjustment timer 25 counts down is set. The storage device 15 is searched and held (step S2202). At this time, the elapsed time Tk (seconds) is gradually counted down from 10 seconds to 0 seconds, for example, and the adjustment decrease rate Rt gradually increases from 50% to 100%.

  Next, the voltage output value of the detection information detected by the accelerator opening sensor 16 is acquired (step S2203), and the operation detected by the accelerator opening sensor 16 using the search map shown in FIG. The requested torque Td1 corresponding to the accelerator operation (voltage output value) of the person is searched (step S2204).

  Thereafter, the output torque Tout derived according to the amount of depression of the driver's accelerator pedal is reduced by torque suppression control by multiplying the required torque Td1 held in the previous step S2204 by the previous adjustment reduction rate Rt. The output torque Touch is adjusted so as to be increased and returned (step S2205).

  Next, the current output torque Tout (current value) obtained in the previous step S2205 is a value obtained by adding the torque increase limit value Lu1 per unit time to the previous output torque Tout (previous value) or the torque output of the electric motor 12. It is confirmed whether or not the maximum value Lt is exceeded (step S2206), and if it is not exceeded, the current value is adopted (step S2207). The value obtained by adding the limit value Lu1 to the value or the smaller output torque maximum value Lt is adopted (step S2208) and held as the output torque Tout.

  Thus, the electric vehicle 10 can gradually return the torque output adjusted when the motor lock is generated to a value corresponding to the accelerator operation by the driver, and smoothly switch the torque output from one of suppression and increase to the other. Can be continuous. For this reason, the motor lock countermeasure control process is continued without surprised the driver, notifying that the electric motor 12 is in the locked state, or noticing the backward or forward movement, and stepping on the brake pedal. You can encourage replacement.

  Next, as shown in the flowchart of FIG. 14, the torque control release determination unit 20F (ECU 20) first performs an operation that does not cause the electric motor 12 to generate a motor lock as the torque control release determination process in step S23. The confirmation timer 24 for confirming whether or not is activated after resetting and starts counting the elapsed time Ta (step S2301).

  Next, a detection (sensing) signal of a switch for detecting depression of the accelerator pedal or a switch for detecting depression of the brake pedal is acquired to check whether the accelerator is on or off (step S2302).

  In step S2302, when neither the accelerator on or the accelerator off can be confirmed, it is determined that the driver's foot is not separated from the accelerator pedal (the motor motor 12 is not in a state where the motor cannot be locked), and the process proceeds to step S2303. Thus, “0” is stored in the torque control release determination flag Fr, and the torque control release determination process is terminated. In this step S2302, if either the accelerator on or the accelerator off can be confirmed, it is determined whether the driver's foot is away from the accelerator pedal but the operation is intentional or just happens to happen. Therefore, it is confirmed whether or not the elapsed time Ta measured by the confirmation timer 24 has exceeded a preset time (step S2304).

  If it cannot be confirmed in step S2304 that the accelerator-on or accelerator-off operation exceeds the set time, the driver's foot is away from the accelerator pedal, but it cannot be said that the operation is intentional. Again, the process returns to step S2302, and the same processing is repeated. In this step S2304, if it can be confirmed that the accelerator-on or accelerator-off operation has continued beyond the set time, it is assumed that the driver's foot is separated from the accelerator pedal by an intentional operation. Proceeding to step S2305, "1" is stored in torque control release determination flag Fr, and this torque control release determination processing is terminated.

  As a result, the torque control release determination unit 20F detects that the power supply to the electric motor 12 by the operation of the accelerator pedal is stopped and the motor lock is surely generated, and the countermeasure control is performed. The processing can be terminated, and the torque control at the time of starting can be executed again to perform efficient torque control. At this time, whether or not the torque control can be canceled is determined based on whether or not the accelerator pedal or the brake pedal is depressed, and the driver's operation can be directly detected and controlled, and the electric motor 12 is immediately de-energized. be able to.

  As described above, in this embodiment, the fact that the electric motor 12 is damaged by the motor lock that maintains the stopped state of the electric vehicle 10 by the driving force (output torque) of the electric motor 12, the backward retreat and the uphill Can be avoided by switching the energized phase of the electric motor 12 by repeating the forward short-distance movement in this direction. At this time, since the short-distance movement in the front-rear direction is repeated, it collides with an obstacle in front or rear. Can be prevented and safety can be improved. Therefore, the motor lock state of the electric motor 12 can be noticed more positively and safely than in the case of movement in only one direction before and after that, and the switch from the accelerator pedal to the brake pedal is surely urged. Can do.

  Next, FIG. 15 is a diagram showing a second embodiment of the motor control device for an electric vehicle according to the present invention. Here, since the present embodiment is configured in substantially the same manner as the above-described embodiment, the same reference numerals are given to the same configurations using the drawings, and the characteristic portions will be described.

  In FIG. 15, when the ECU 20 of the electric vehicle 10 executes the motor lock countermeasure control process, the above-described embodiment performs the torque suppression control of the electric motor 12 to start from the backward movement, and then the uphill direction. On the contrary, the ECU 20 of the present embodiment performs the torque increase control of the electric motor 12 to start the advance in the uphill direction, and thereafter , Torque suppression control for retreating in the downward direction is executed.

  Specifically, as in the above-described embodiment, when it is confirmed that the electric vehicle 10 is almost stopped (vehicle speed≈0 km / hour) (step S11), after determining whether the electric motor 12 is abnormal (step S11) S12, S13), the motor lock countermeasure control process is executed, and one of the suppression control or increase control of the output torque of the electric motor 12 is continued (steps S20, S21 ′, S44 to S48, S56 to S60). When the rotation angle θ (rad) of the electric motor 12 exceeds the set rotation angle such as 120 ° for one phase by the suppression control or the increase control, the electric motor 12 is returned to the normal torque output. (Step S22). After this, when the output torque control of the electric motor 12 cannot be canceled and the motor lock countermeasure control process is continued (steps S23 and S24), the suppression control and increase control of the electric motor 12 are repeated (step S23). S25 ′) After the motor lock state is released while avoiding damage to the electric motor 12, the motor lock countermeasure control process is terminated.

  In steps S44 to S48 in the present embodiment, processing similar to that in steps S26 to S30 in the above-described embodiment is executed, and also in steps S56 to S60, processing similar to that in steps S14 to S18 in the above-described embodiment. Since I am just running, I will omit further explanation. Steps S21 'and S25' are substantially the same processing steps as steps S21 and S25 and the skip destinations in the above-described embodiment are changed in accordance with steps S44 to S48 and S56 to S60. doing.

  Thus, in this embodiment, the same operation effect as the above-mentioned embodiment can be obtained, and it can prevent beforehand that electric motor 12 will be damaged by motor lock.

  The scope of the present invention is not limited to the illustrated and described exemplary embodiments, but also includes all embodiments that provide equivalent effects to those intended by the present invention. Further, the scope of the invention is not limited to the combinations of features of the invention defined by the claims, but may be defined by any desired combination of particular features among all the disclosed features. .

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 10 Electric vehicle 11 High voltage battery 12 Electric motor 13 Drive wheel 15 Memory | storage device 16 Accelerator opening degree sensor 17 Vehicle speed sensor 20 ECU
20A Motor abnormality determination unit 20B Motor lock determination unit 20C Travel direction state determination unit 20D Torque suppression control unit 20E Torque increase control unit 20F Torque control release determination unit 20G Torque control release unit 21 Motor rotation angle detection device 22 Torque detection device 23 Coil temperature Detector 24 Confirmation timer 25 Adjustment timer 26 Obstacle detection device

Claims (9)

A motor control device mounted on the vehicle together with an electric motor that functions as a drive source for running the vehicle,
An abnormality determination unit for determining whether an abnormality has occurred in the electric motor;
An angle detector for detecting a rotation angle of the electric motor;
Detecting that the electric motor is in a locked state based on a rotation angle of the electric motor after a predetermined time has elapsed from a reference time detected by the angle detection unit while the electric motor is outputting driving force. A lock detector to perform,
When it is determined by the abnormality determination unit that no abnormality has occurred in the electric motor, and the lock detection unit detects the lock state of the electric motor, the vehicle is moved in the forward or backward direction, and thereafter When the angle detection unit detects the rotation of the electric motor at a preset angle, the output of the electric motor is moved so as to move in a direction opposite to the forward direction or in a direction opposite to the reverse direction. A motor control device for an electric vehicle, comprising: a torque control unit that adjusts torque.   The abnormality determination unit determines whether an abnormality has occurred in the electric motor based on at least one of the coil temperature of the electric motor, the input power of the electric motor, and the actual torque output from the electric motor. The driving force control apparatus for an electric vehicle according to claim 1, wherein: The electric motor is configured such that the rotor in the stator is driven to rotate by energizing the coils of the plurality of phases.
3. The torque control unit according to claim 1, wherein a rotation angle of at least one phase of the electric motor is set as an angle for switching the movement of the vehicle in the forward direction or the reverse direction. The motor control apparatus of the electric vehicle described in 2. The angle detection unit includes a detection coil disposed on the stator side of the electric motor, and an excitation coil disposed on the rotor side of the electric motor,
The motor control device for an electric vehicle according to any one of claims 1 to 3, wherein the rotational position is detected based on an electromotive force generated in the excitation coil on the rotor side. The torque control unit gradually changes the adjustment amount of the output torque after starting the adjustment of the output torque when the vehicle is moved in the reverse direction so as to smoothly continue to the unadjusted output torque of the electric motor. The motor control device for an electric vehicle according to any one of claims 1 to 4, wherein the motor control device is an electric vehicle. The torque control unit cancels the adjustment control for gradually changing the adjustment amount of the output torque at the start of the adjustment control for gradually changing the adjustment amount of the output torque or the adjustment amount of the output torque of the electric motor. 6. The motor control device for an electric vehicle according to claim 5, wherein the determination is made by searching from an adjustment map set in advance according to an elapsed time from the start of the determination process .   The said torque control part cancels | releases the adjustment control of the output torque of the said electric motor based on the sensor information which detected the accelerator pedal non-depressing operation or the depression operation of a brake pedal. 2. A motor control device for an electric vehicle according to item 1. An obstacle detection unit for detecting the presence or absence of an obstacle present in the traveling direction of the vehicle;
8. The torque control unit according to claim 1, wherein the torque control unit performs adjustment control of an output torque of the electric motor when an obstacle in a traveling direction is not detected by the obstacle detection unit. The motor control apparatus of the electric vehicle as described in the item.   9. The motor control for an electric vehicle according to claim 8, wherein the torque control unit continues the adjustment control of the output torque of the electric motor in the traveling direction in which the obstacle detection unit does not detect an obstacle. apparatus.

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