JP2021188586A - Control device - Google Patents

Abstract

To provide a control device which can reversely operate a rotating electric machine in which a commutation sensor for acquiring commutation position information is arranged by merely one phase without causing a power swing of the rotating electric machine.SOLUTION: A control device 10 comprises a position information estimation part 11 for estimating commutation position information on a first phase, a second phase and a third phase of a rotating electric machine 30, and an angular acceleration estimation part 13 for estimating the angular acceleration of the rotating electric machine 30. The position information estimation part 11 estimates the commutation position information on the first phase on the basis of a signal from a commutation sensor 31, and on the other hand, estimates the commutation position information on the second phase and the third phase on the basis of the estimated angular acceleration. When reversely operating the rotating electric machine 30, the angular acceleration estimation part 13 estimates the angular acceleration by a second estimation method in which a value of the angular acceleration is estimated as a small value rather than a first estimation method when forwardly operating the rotating electric machine.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a vehicle control device.

A vehicle having an internal combustion engine is provided with a rotary electric machine for starting the internal combustion engine. The rotary electric machine is also generally referred to as a "starter motor".

When the internal combustion engine is started by the rotary electric machine, the rotary electric machine operates while resisting the load torque received from the internal combustion engine. Such a load torque tends to be particularly large in the vicinity of a position where the crank angle of the internal combustion engine is an angle at which the compression process is switched to the explosion process. Therefore, for example, if an attempt is made to start the internal combustion engine by a rotary electric machine while the crank angle is immediately before the above position, the approach distance is insufficient and the internal combustion engine is started over the above position. May not be possible.

Therefore, in the control device described in Patent Document 1 below, the rotary electric machine is operated in reverse in advance when the internal combustion engine is stopped. As a result, the approaching distance at the time of starting is always secured, so that the internal combustion engine can be started stably.

Japanese Patent No. 5929342

By the way, in controlling a rotary electric machine operated by three-phase AC power, the commutation position information for each of the first phase, the second phase, and the third phase is estimated or acquired, and these commutation position information is obtained. It is necessary to control the current of each phase based on. For this reason, the rotary electric machine generally has a built-in sensor for acquiring the commutation position information and outputting it to the outside.

The "commutation position information" is the relative relationship between the coils of the first phase, the second phase, and the third phase provided in the stator of the rotary electric machine and the permanent magnets provided in the rotor. It is information showing a typical positional relationship. The above sensor uses a signal that alternately switches between L and H as commutation position information each time the rotation angle of the rotary electric machine changes by a predetermined angle (for example, 180 degrees). In general, the sensor is often provided individually for each of the first, second, and third phase coils. In this case, the commutation position information corresponding to each of the first phase, the second phase, and the third phase is output individually.

In the rotary electric machine, sensors for acquiring the commutation position information and outputting it to the outside are not individually provided corresponding to the coils of the first phase, the second phase, and the third phase. , There are some that are provided only for the first phase. The present inventors are studying how to reverse-operate the rotary electric machine in the same manner as the control described in Patent Document 1 while using the rotary electric machine having such an inexpensive configuration.

When operating the rotary electric machine having the above configuration, the commutation position information of the second phase and the third phase cannot be obtained from the sensor, so these can be used as the commutation position information of the first phase obtained by the sensor. It needs to be estimated based on. However, it is generally difficult to always accurately estimate the commutation position information, and the rotation electric machine may be out of step due to the deviation of the estimation. In particular, when the rotary electric machine is reversely operated before the start of the internal combustion engine, the crank angle at the present time is often unknown, so that the rotary electric machine is particularly likely to be out of step.

An object of the present disclosure is to provide a control device capable of reversely operating a rotary electric machine provided with only one phase of a sensor for acquiring commutation position information without causing step-out. do.

The control device according to the present disclosure is a vehicle (MV) control device (10). The vehicle to be controlled is provided with an internal combustion engine (20) for generating a driving force for traveling and a rotary electric machine (30) for starting the internal combustion engine. This control device is used for the position information estimation unit (11) that estimates the commutation position information for each of the first phase, the second phase, and the third phase in the rotary electric machine, and the estimated commutation position information. Based on this, an operation control unit (12) for controlling the operation of the rotary electric machine and an angular acceleration estimation unit (13) for estimating the angular acceleration of the rotary electric machine are provided. The operation control unit is configured to perform a preparatory process for causing the rotary electric machine to reversely operate in advance before the internal combustion engine is started. The position information estimation unit estimates the commutation position information for the first phase based on the signal from the commutation sensor (31) provided in the rotary electric machine, while the position information estimation unit estimates the commutation position information for each of the second phase and the third phase. The commutation position information is estimated based on the angular acceleration estimated by the angular acceleration estimation unit with reference to the commutation position information for the first phase. The angular acceleration estimation unit estimates the angular acceleration of the rotary electric machine by the first estimation method when the rotary electric machine is rotated in the forward direction, and when the rotary electric machine is rotated in the reverse direction for the preparatory process, the angular acceleration estimation unit rotates more than the first estimation method. The angular acceleration of the rotary electric machine is estimated by the second estimation method in which the angular acceleration value of the electric machine is calculated as a small value.

In the control device having such a configuration, the commutation position information for each of the second phase and the third phase is estimated based on the angular acceleration of the rotary electric machine estimated by the angular acceleration estimation unit, and the estimated commutation. The operation of the rotary electric machine is controlled based on the position information. The angular acceleration estimation unit estimates the angular acceleration of the rotary electric machine by the first estimation method when the rotary electric machine is rotated in the forward direction, and when the rotary electric machine is rotated in the reverse direction for the preparatory process, the angular acceleration estimation unit rotates more than the first estimation method. The angular acceleration of the rotary electric machine is estimated by the second estimation method in which the angular acceleration value of the electric machine is calculated as a small value.

The angular acceleration of the rotary electric machine estimated by the second estimation method is estimated as a smaller value than the angular acceleration estimated by the first estimation method. Therefore, the commutation position information of the second phase and the third phase estimated based on the angular acceleration is estimated to be switched at a later timing than the actual one.

As described above, if there is a discrepancy between the estimated commutation position information and the actual commutation position information, there is a high possibility that the rotary electric machine will be out of step. However, according to the experiments conducted by the present inventors, when the commutation position information is estimated to be switched at a later timing than the actual timing, it is estimated to be switched at an earlier timing than the actual timing. It has been found that step-out is relatively less likely to occur than in the case of.

As described above, if the angular acceleration of the rotary electric machine is estimated by the second estimation method when the rotary electric machine is operated in reverse, it is estimated that the commutation position information is switched at a timing earlier than the actual timing. It never ends up. Therefore, it is possible to reverse the rotary electric machine without causing step-out.

According to the present disclosure, there is provided a control device capable of reversely operating a rotary electric machine provided with only one phase of a commutation sensor for acquiring commutation position information without causing step-out. To.

FIG. 1 is a diagram schematically showing a configuration of a control device according to the present embodiment and a configuration of a vehicle on which the control device is mounted. FIG. 2 is a diagram schematically showing a configuration of a drive circuit for operating a rotary electric machine. FIG. 3 is a diagram showing an example of time change of a signal or the like indicating commutation position information. FIG. 4 is a diagram for explaining a method of estimating the commutation position information. FIG. 5 is a diagram for explaining the load torque received by the rotary electric machine. FIG. 6 is a flowchart showing a flow of processing executed by the control device. FIG. 7 is a flowchart showing the flow of processing executed by the control device. FIG. 8 is a flowchart showing the flow of processing executed by the control device.

Hereinafter, the present embodiment will be described with reference to the accompanying drawings. In order to facilitate understanding of the description, the same components are designated by the same reference numerals as possible in the drawings, and duplicate description is omitted.

The control device 10 according to the present embodiment is mounted on the vehicle MV, and is configured as a device for performing various controls on the vehicle MV. The control includes, for example, control for starting the internal combustion engine 20, operation control of the internal combustion engine 20 after the start, and the like.

FIG. 1 schematically shows the configuration of the vehicle MV and the control device 10. As shown in the figure, the vehicle MV includes an internal combustion engine 20 and a rotary electric machine 30. The internal combustion engine 20 is a device for generating a driving force for traveling of a vehicle MV by burning fuel. The internal combustion engine 20 is configured as a 4-cycle reciprocating engine.

The rotary electric machine 30 is a so-called "starter motor", which is a device for rotating the crankshaft (not shown) of the internal combustion engine 20 and thereby starting the internal combustion engine 20. The rotary electric machine 30 is configured as a three-phase motor, and operates by being supplied with three-phase AC power including a U-phase, a V-phase, and a W-phase. The operation of the rotary electric machine 30 is controlled by the control device 10 as described later. The rotary electric machine 30 includes a commutation sensor 31 and a drive circuit 300.

The commutation sensor 31 is configured as a sensor for acquiring commutation position information of the W phase among the above U phase, V phase, and W phase and outputting a signal corresponding to the information. The "commutation position information" is the relative position between the U-phase, V-phase, and W-phase coils provided in the stator of the rotary electric machine 30 and the permanent magnets provided in the rotor. Information indicating the relationship. That is, it is information indicating the rotation angle (that is, phase) of the rotor possessed by the rotary electric machine 30. In the present embodiment, the above-mentioned commutation position information is used as information for alternately switching between L and H each time the rotation angle of the rotary electric machine 30 changes by 180 degrees. Depending on the configuration of the rotary electric machine 30, the above angle of "180 degrees" may be changed.

Such commutation position information is information that should be estimated individually for each of the phases, but only the commutation position information for the W phase is detected by the commutation sensor 31. The W phase in which the commutation position information is detected by the commutation sensor 31 corresponds to the "first phase" in the present embodiment. The other V phase and U phase correspond to the "second phase" and the "third phase" in the present embodiment, respectively. Although the commutation sensor 31 is schematically drawn at a position away from the rotary electric machine 30 in FIG. 1, the commutation sensor 31 is actually built in the rotary electric machine 30. ..

The drive circuit 300 is a circuit for adjusting the U-phase, V-phase, and W-phase electric powers supplied to the rotary electric machine 30 to adjust the operation of the rotary electric machine 30. The operation of the drive circuit 300 is controlled by the control device 10.

As shown in FIG. 2, the drive circuit 300 is configured as an inverter circuit having six switching elements 311, 312, 321, 322, 332, 332. The switching elements 311 and 312 are elements for adjusting the power of the U phase, which is the third phase. The switching element 311 is arranged at a position that becomes the upper arm of the U phase, and the switching element 312 is arranged at a position that becomes the lower arm of the U phase.

The switching elements 321 and 322 are elements for adjusting the power of the V phase, which is the second phase. The switching element 321 is arranged at a position that becomes the upper arm of the V phase, and the switching element 322 is arranged at a position that becomes the lower arm of the V phase.

The switching elements 331 and 332 are elements for adjusting the power of the W phase, which is the first phase. The switching element 331 is arranged at a position that becomes the upper arm of the W phase, and the switching element 332 is arranged at a position that becomes the lower arm of the W phase.

In FIG. 2, the reference numeral “350” is attached to the storage battery provided in the vehicle MV. The drive circuit 300 converts the DC power supplied from the storage battery into three-phase AC power and supplies it to the rotary electric machine 30 by opening and closing each of the switching elements 311 and the like. The opening / closing operation of the switching element 311 or the like is controlled by the control device 10.

The configuration of the control device 10 will be described with reference to FIG. 1 continuously. The control device 10 is configured as a computer system including a CPU, a ROM, a RAM, and the like. The control device 10 includes a position information estimation unit 11, an operation control unit 12, and an angular acceleration estimation unit 13 as block elements representing the functions thereof.

The position information estimation unit 11 performs a process of estimating the commutation position information for each of the W phase (first phase), the V phase (second phase), and the U phase (third phase) in the rotary electric machine 30. It is a part. As described above, the rotary electric machine 30 is provided with a commutation sensor 31 for detecting the commutation position information of the W phase. Therefore, the position information estimation unit 11 estimates the commutation position information for the W phase based on the signal from the commutation sensor 31. On the other hand, the position information estimation unit 11 estimates the commutation position information for each of the V phase and the U phase based on the angular acceleration of the rotary electric machine 30 with reference to the commutation position information for the W phase. As the "angular acceleration of the rotary electric machine 30", a value estimated by the angular acceleration estimation unit 13 described later is used. A specific method for the position information estimation unit 11 to estimate the commutation position information will be described later.

The operation control unit 12 is a unit that controls the operation of the rotary electric machine 30 based on the respective commutation position information of the W phase, the V phase, and the U phase estimated by the position information estimation unit 11. .. The operation control unit 12 controls the operation of the rotary electric machine 30 by controlling the opening / closing operation of the switching element 311 and the like included in the drive circuit 300.

The angular acceleration estimation unit 13 is a part that performs a process of estimating the angular acceleration of the rotary electric machine 30. As described above, the angular acceleration estimated by the angular acceleration estimation unit 13 is used for the estimation of the commutation position information by the position information estimation unit 11. A specific method for the angular acceleration estimation unit 13 to estimate the angular acceleration of the rotary electric machine 30 will be described later.

The control device 10 having the above configuration may be configured as a single device, but may be configured as a plurality of devices that operate in cooperation with each other. The specific device configuration of the control device 10 for realizing the functions described below is not particularly limited.

In addition to the commutation sensor 31, signals from various sensors provided in the vehicle MV are input to the control device 10. FIG. 1 shows a crank angle sensor 21 as one of these sensors. The crank angle sensor 21 is a sensor for detecting the rotation angle of the crankshaft (not shown) of the vehicle MV, that is, the crank angle. The control device 10 can acquire the current crank angle value based on the signal from the crank angle sensor 21.

With reference to FIG. 3, changes in commutation position information during operation of the rotary electric machine 30 and the like will be described. FIG. 3A shows an example of a change in commutation position information for the W phase. As described above, the commutation position information about the W phase is detected by the commutation sensor 31. The commutation sensor 31 outputs a signal that alternately switches between H and L, as in the example of FIG. 3A, every time the rotation angle of the rotary electric machine 30 changes by 180 degrees.

FIG. 3B shows an example of a change in commutation position information for the V phase. Further, what is shown in FIG. 3C is an example of a change in the commutation position information for the U phase. As described above, the rotary electric machine 30 is not provided with a sensor for detecting the commutation position information of these two phases. Therefore, the commutation position information shown in FIGS. 3 (B) and 3 (C) cannot be directly detected by the sensor and is estimated by the position information estimation unit 11. It is a thing.

In each of the W phase, the V phase, and the U phase, the timing at which the commutation position information is switched between H and L is the timing at which the rotation angle of the rotor deviates from each other by a predetermined angle. The above-mentioned "predetermined angle" is 1/3 of the angle in the range in which the commutation position information does not change and is constant, that is, 60 degrees in the present embodiment.

For example, in the example of FIG. 3, the rotation of the U phase is changed from the timing when the commutation position information of the W phase changes from L to H (arrow AR1) to the timing when the rotation angle of the rotor changes by 60 degrees (arrow AR2). The flow position information is changing from H to L. Further, at the timing (arrow AR3) in which the rotation angle of the rotor is further changed by 60 degrees from the timing, the commutation position information of the V phase changes from L to H. From this timing, at the timing when the rotation angle of the rotor is further changed by 60 degrees (arrow AR4), the commutation position information of the W phase is changed from H to L again.

The rotary electric machine 30 is not provided with a sensor that detects the rotation angle of the rotor with high resolution. Therefore, the position information estimation unit 11 cannot estimate the change in the commutation position information of the V phase and the U phase based on the change in the rotation angle of the rotor. As will be described later, the position information estimation unit 11 calculates the elapsed time required for the commutation position information of each phase to change based on the angular acceleration estimated by the angular acceleration estimation unit 13, and the elapsed time. It is configured to estimate the change timing of the commutation position information based on.

When the commutation position information of each phase is estimated as shown in FIGS. 3 (A), 3 (B), and 3 (C), the operation control unit 12 operates the rotary electric machine 30 based on these. To control.

FIG. 3D shows an example of the opening / closing operation of the switching element 331 arranged at the position of the upper arm of the W phase. In this example, the switching element 331 is switched to the closed state (ON) at the timing when the commutation position information of the W phase shown in FIG. 3 (A) changes from L to H, and the commutation position information is H. It is controlled to switch to the open state (OFF) at the timing of changing from to L.

FIG. 3E shows an example of the opening / closing operation of the switching element 332 arranged at the position of the lower arm of the W phase. In this example, the switching element 332 switches to the open state (OFF) at the timing when the commutation position information of the W phase shown in FIG. 3A changes from L to H, and the commutation position information becomes H. It is controlled to switch to the closed state (ON) at the timing of changing from L to L.

FIG. 3F shows an example of the opening / closing operation of the switching element 321 arranged at the position of the upper arm of the V phase. In this example, the switching element 321 is switched to the closed state (ON) at the timing when the V-phase commutation position information shown in FIG. 3B changes from L to H, and the commutation position information is H. It is controlled to switch to the open state (OFF) at the timing of changing from to L.

FIG. 3 (G) shows an example of the opening / closing operation of the switching element 322 arranged at the position of the lower arm of the V phase. In this example, the switching element 322 switches to the open state (OFF) at the timing when the V-phase commutation position information shown in FIG. 3B changes from L to H, and the commutation position information becomes H. It is controlled to switch to the closed state (ON) at the timing of changing from L to L.

FIG. 3H shows an example of the opening / closing operation of the switching element 311 arranged at the position of the upper arm of the U phase. In this example, the switching element 311 switches to the closed state (ON) at the timing when the U-phase commutation position information shown in FIG. 3C changes from H to L, and the commutation position information is L. It is controlled to switch to the open state (OFF) at the timing of changing from H to H.

FIG. 3I shows an example of the opening / closing operation of the switching element 312 arranged at the position of the lower arm of the U phase. In this example, the switching element 312 switches to the open state (OFF) at the timing when the U-phase commutation position information shown in FIG. 3C changes from H to L, and the commutation position information is L. It is controlled to switch to the closed state (ON) at the timing of changing from H to H.

As in the above example, the operation control unit 12 opens and closes the switching element 311 and the like at the timing based on the change in the commutation position information of each phase, thereby operating the rotary electric machine 30. Further, the operation control unit 12 also performs a process of adjusting the torque generated by the rotary electric machine 30 by shifting the timing at which the switching of the switching element 311 and the like is switched from the timing at which the commutation position information of each phase changes. As a specific method for controlling the operation of the rotary electric machine 30 based on such a change in the commutation position information of each phase, various known methods can be adopted.

Subsequently, a method in which the angular acceleration estimation unit 13 estimates the angular acceleration of the rotary electric machine 30 will be described. The angular acceleration estimation unit 13 estimates the angular acceleration of the rotary electric machine 30 by using any of two types of methods including a first estimation method and a second estimation method.

In the first estimation method, the angular acceleration α ₁ is estimated by the following equation (1).
_{α 1 = (T M -T L} ) / I ··· (1)

"T _M" in the formula (1) is the value of the drive torque generated by the rotary electric machine 30. Such T _M, for example, can be calculated based on the opening and closing timing of the switching element 311 such as in the example of FIG. Also, based on measurements of the power of the voltage and current supplied to the rotary electric machine 30, may be above T _M is calculated. Furthermore, the operation control unit 12 is a target value of the driving torque at the time of performing control of the rotary electric machine 30, it may be used as the above-described T _M.

_"TL " in the formula (1) is a value of the load torque received when the rotary electric machine 30 rotates the internal combustion engine 20. Such a _TL value is obtained in advance by an experiment or the like corresponding to each value of the crank angle. The control device 10 can calculate the value _{of the load torque TL at} the present time according to the crank angle detected by the crank angle sensor 21. "I" in the formula (1) is the moment of inertia of the member rotated by the rotary electric machine 30.

In the second estimation method, the angular acceleration α ₂ is estimated by the following equation (2).
_{α 2 = (T M -max (} T L)) / I ··· (2)

The equation (2) is an equation in which " _TL " in the equation (1) is replaced with "max ( _TL )". max ( _TL ) is the maximum value of _TL that changes with the operation of the rotary electric machine 30. Specifically, max ( _TL ) is the maximum value _{that the variable load torque TL} can take when the motion control unit 12 reversely operates the rotary electric machine 30 for the preparation process described later. .. _{Α 2} calculated by the equation (2) is the angular acceleration of the rotary electric machine 30 when the load torque is the maximum value in the operating range. Therefore, the value of _{α 2} is estimated as a value smaller than the value of _{α 1.} In other words, the second estimation method can be said to be an estimation method in which the value of the angular acceleration of the rotary electric machine 30 is estimated as a smaller value than the first estimation method.

The value of max ( _TL ) can be calculated or experimentally obtained in advance in consideration of various factors that may affect the load torque. Examples of the element include frictional resistance between each member constituting the internal combustion engine 20 and inertial resistance of each member. In addition, the spring force of the valve springs provided in the intake valve and exhaust valve (both not shown) provided in the internal combustion engine 20, the viscosity of the lubricating oil supplied to the internal combustion engine 20, and the cooling supplied to the internal combustion engine 20. The pumping resistance when pumping water with a pump, the rotational resistance when rotating the cooling fan for pumping air into the radiator, etc. are also mentioned as factors that can be considered when calculating the value of _{max (TL).} Be done.

The position information estimation unit 11 describes a method of estimating the commutation position information. FIG. 4A shows an example of a change in the commutation position information for the W phase, as in FIG. 3A. FIG. 4B shows an example of a change in the commutation position information for the V phase, as in FIG. 3B. FIG. 4C shows an example of changes in the commutation position information for the U phase, as in FIG. 3C.

In the example of FIG. 4, the timing at which the commutation position information for the W phase is switched from L to H is shown as time t1. The timing at which the commutation information about the U phase is switched from H to L after the time t1 is shown as the time t2. The timing at which the commutation information about the V phase is switched from L to H after the time t2 is shown as the time t3. The timing at which the commutation position information for the W phase is switched from H to L after the time t3 is shown as the time t4.

As described above, in each of the W phase, V phase, and U phase, the timing at which the commutation position information is switched between L and H is 60 degrees with respect to the rotation angle of the rotor of the rotary electric machine 30. The timings are shifted by each. That is, every time the rotation angle of the rotor changes by 60 degrees, the timings of the above times t1, t2, t3, and t4 come in order.

Therefore, if the rotary electric machine 30 is rotating at a constant angular velocity (that is, when the angular acceleration is 0), the period α from time t1 to time t2 and the period β from time t2 to time t3. , And the period γ from the time t3 to the time t4 are all periods of the same length.

In this case, assuming that the length of the period in which the commutation position information for the W phase is L before the time t1 is TM, the respective lengths of the period α, the period β, and the period γ are 1 / of the TM. It should be 3. Therefore, the timing at which the TM / 3 period elapses from the time t1 when the commutation sensor 31 detects that the commutation position information for the W phase is switched from L to H is the commutation for the U phase. It can be estimated as the timing (time t2) when the flow position information is switched from H to L. Similarly, the timing at which the TM / 3 period has further elapsed from the time t2 can be estimated as the timing (time t3) when the commutation information for the V phase is switched from L to H.

However, the angular acceleration of the rotary electric machine 30 is not 0 in many cases. For example, when the value of the angular acceleration is a positive value and the angular velocity of the rotary electric machine 30 gradually increases, the period α becomes shorter than TM / 3, for example, (TM / 3) / K. Similarly, the period β is even shorter, for example, the ^{(TM / 3) / K 2} . It becomes shorter period gamma, for example, the ^{(TM / 3) / K 3} . It should be noted that "K" in each of the above values is a value larger than 1.0 and is a constant determined corresponding to the angular acceleration of the rotary electric machine 30. The larger the angular acceleration of the rotary electric machine 30, the larger the value of K. Therefore, if the angular acceleration of the rotary electric machine 30 is known, it is possible to set the value of K based on the angular acceleration and calculate the respective lengths of the periods α, β, and γ using the K.

The position information estimation unit 11 determines the value of K above based on the angular acceleration of the rotary electric machine 30 estimated by the angular acceleration estimation unit 13. After that, the position information estimation unit 11 calculates the respective lengths of the periods α, β, and γ as in the above example by using the determined value of K.

Using the commutation position information for the W phase, that is, the time t1 obtained from the signal from the commutation sensor 31, the lengths of the periods α, β, and γ calculated as described above are used. The timings of the times t2 and t3 can be estimated. That is, the time t3 can be estimated as the timing at which the commutation position information for the V phase is switched, and the time t2 can be estimated as the timing at which the commutation position information for the U phase is switched. The position information estimation unit 11 estimates the commutation position information of each phase based on the angular acceleration of the rotary electric machine 30 by the above method.

The process executed by the operation control unit 12 at the time of starting the internal combustion engine 20 will be described. FIG. 5 shows the relationship between the phase of the crank angle (horizontal axis) and the load torque (vertical axis) received from the internal combustion engine 20 by the rotary electric machine 30. When the internal combustion engine 20 is started, the crank angle changes toward the right side in FIG. 5 due to the driving force of the rotary electric machine 30. The direction of the change is the same as the direction in which the crank angle changes when the internal combustion engine 20 is operating. The operation of the rotary electric machine 30 that changes the crank angle in that direction is also referred to as "normal rotation operation" below.

As shown in FIG. 5, the load torque when the rotary electric machine 30 is in the normal rotation operation gradually increases in the compression process and becomes maximum at the timing of switching from the compression process to the explosion (combustion) process. In FIG. 5, such load torque peaks are shown as "PK1" and "PK2".

In addition to the above timings, there are timings when the load torque increases. “PK3” shown in FIG. 5 is the peak of the load torque caused by the lifting of the intake valve in the middle of the intake process. Although such a peak is smaller than that of PK1 and PK2, it cannot be ignored because it may affect the control of the rotary electric machine 30.

When the internal combustion engine 20 is started, if the initial crank angle is P1 in FIG. 5, the load torque suddenly increases immediately after the rotary electric machine 30 starts the normal rotation operation. In this case, since the approaching distance is insufficient, the rotary electric machine 30 may not be able to operate the internal combustion engine 20 beyond the peak PK1 of the load torque.

Therefore, in the control device 10 according to the present embodiment, the motion control unit 12 is supposed to reverse-operate the rotary electric machine 30 in advance before the internal combustion engine 20 is started. The "reverse rotation operation" is an operation of the rotary electric machine 30 that rotates in the direction opposite to that of the normal rotation operation. The process of causing the rotary electric machine 30 to reversely operate before the start of the internal combustion engine 20 is also referred to as "preparation process" below.

When the initial crank angle is P1 in FIG. 5, the operation control unit 12 performs the above-mentioned preparatory process, so that the crank angle changes in the direction of the arrow AR5. At that time, since the load torque increases toward PK2, the rotary electric machine 30 stops when the load torque exceeds the torque of the rotary electric machine 30. For example, when the magnitude of the torque of the rotary electric machine 30 is the value shown by the dotted line DL1 in FIG. 5, the rotary electric machine 30 is stopped when the crank angle becomes P2. It can be determined that the rotary electric machine 30 has stopped, for example, based on a signal from the crank angle sensor 21.

After that, when the motion control unit 12 rotates the rotary electric machine 30 in the normal direction, the rotary electric machine 30 operates the internal combustion engine 20 so as to overcome the PK1 because the crank angle reaches PK1 after the rotation speed becomes sufficient. be able to. That is, if the preparatory process is performed in advance, a sufficient approach distance is secured from the position of P2, so that the internal combustion engine 20 can be stably started by overcoming the load torque.

In the preparatory process, the crank angle P2 at which the reverse rotation operation of the rotary electric machine 30 is stopped is a known value that can be obtained in advance by an experiment or the like. Therefore, the control device 10 can grasp the current crank angle at the timing when the reverse rotation operation of the rotary electric machine 30 is stopped. After that, since the value of the crank angle can be continuously grasped according to the signal from the crank angle sensor 21, the control device 10 can stably control the operation of the rotary electric machine 30 based on the crank angle. It will be possible.

The crank angle at the present time may be grasped at the timing when the reverse rotation operation of the rotary electric machine 30 is stopped as described above, but the signal from the crank angle sensor 21 indicates the passage of the missing tooth. It may be performed at the timing of. In any case, after the reverse rotation operation is completed, the control device 10 can stably control the operation of the rotary electric machine 30 based on the crank angle.

In other words, it is difficult to stably control the operation of the rotary electric machine 30 before the reverse rotation operation is completed and during the period when the control device 10 has not yet grasped the current crank angle. In particular, when passing through the position of PK3 during reverse rotation operation, an error occurs in the estimated value of angular acceleration due to an increase in load torque that cannot be predicted based on the crank angle, and rotation is caused by the error. There is a possibility that the electric machine 30 may be out of step.

Therefore, in the control device 10 according to the present embodiment, the rotary electric machine 30 is controlled in a method different from the control method in the normal rotation operation to prevent the rotary electric machine 30 from stepping out. There is.

The specific contents of the control executed by the control device 10 will be described. The series of processes shown in FIG. 6 is executed at the timing when the power switch of the vehicle MV is turned on. The "power switch" is a switch (not shown) provided in the vehicle MV, which is turned on in advance by the driver's operation before starting the internal combustion engine 20. Therefore, at the time when the series of processes shown in FIG. 6 is started, the internal combustion engine 20 is in a stopped state.

In the first step S01, the preparation process is executed. As described above, in the preparatory process, by rotating the rotary electric machine 30 in the reverse direction, the approaching distance for the subsequent forward rotation operation is secured.

In step S02 following step S01, it is determined whether or not the start switch has been operated. The "start switch" is a switch (not shown) provided in the vehicle MV, which is operated by the driver to start the internal combustion engine 20. If the start switch has not yet been operated, the process of step S02 is executed again. When the start switch is operated, the process proceeds to step S03. In step S03, a process of starting the internal combustion engine 20 is performed. Here, so-called cranking is performed by rotating the rotary electric machine 30 in the normal direction, whereby the internal combustion engine 20 is started.

The flowchart of FIG. 7 shows a specific flow of processing performed in step S03 of FIG. In the first step S11, the motion control unit 12 performs a process of starting the forward rotation operation of the rotary electric machine 30. As described with reference to FIG. 3, the operation control unit 12 opens and closes the switching element 311 and the like of the drive circuit 300. Since the drive circuit 300 supplies three-phase AC power to the rotary electric machine 30, the rotary electric machine 30 starts to rotate in the normal direction.

In step S12 following step S11, the angular acceleration of the rotary electric machine 30 is estimated by the angular acceleration estimation unit 13. Here, the angular acceleration is estimated by using the first estimation method described above.

At the time when the process proceeds to step S03 of FIG. 6 and the series of processes shown in FIG. 7 is started, the preparatory process is performed in advance. Therefore, the control device 10 is in a state where the current crank angle value can be grasped according to the signal from the crank angle sensor 21. Therefore, when estimating the _{angular acceleration α 1} using the equation (1) _{, the estimation can be performed while acquiring the load torque TL} as an accurate value corresponding to the crank angle. That is, the value of the angular acceleration estimated in step S12 substantially matches the value of the actual angular acceleration.

In step S13 following step S12, the position information estimation unit 11 estimates the commutation position information for each of the W phase, the V phase, and the U phase, and sets the commutation timing of each phase. The "commutation timing" here is the timing at which the commutation position information is switched between L and H, and is the time t2, t3, etc. in the example of FIG. The commutation timing is set by calculating the respective lengths of the periods α and β in the example of FIG. 4 using the _{angular acceleration α 1 estimated in step S12.}

In step S14 following step S13, the operation of the rotary electric machine 30 is controlled according to the commutation timing of each phase set in step S13. As a result, the normal rotation operation of the rotary electric machine 30 started in step S11 is continuously stably continued even after that.

Due to the preparatory processing performed in advance, the rotary electric machine 30 sufficiently secures the approaching distance before reaching PL1 in FIG. Therefore, the start of the internal combustion engine 20 by the rotary electric machine 30 is not hindered by the load torque.

In step S15 following step S14, it is determined whether or not the start of the internal combustion engine 20 is completed. The determination can be made based on the signal from the crank angle sensor 21. If it is determined that the start of the internal combustion engine 20 has not been completed yet, the processes after step S12 are executed again, and the normal rotation operation of the rotary electric machine 30 is continued. When it is determined that the start of the internal combustion engine 20 is completed, the process proceeds to step S16. In step S16, a process of stopping the normal rotation operation of the rotary electric machine 30 is executed.

Next, the specific contents of the preparatory process will be described. The flowchart of FIG. 8 shows a specific flow of processing performed in step S01 of FIG. In the first step S21, the motion control unit 12 performs a process of starting the reverse operation of the rotary electric machine 30. The process is the same as step S11 in FIG. 7, but is different from step S11 in FIG. 7 in the rotation direction of the rotary electric machine 30. By this process, the rotary electric machine 30 starts to reversely operate.

In step S22 following step S11, the angular acceleration of the rotary electric machine 30 is estimated by the angular acceleration estimation unit 13. Here, the angular acceleration is estimated by using the second estimation method described above.

At the time when the series of processes shown in FIG. 8 is started, the control device 10 does not accurately grasp the crank angle at the present time. Therefore, if the angular acceleration in step S22 is estimated by using the first estimation method instead of the second estimation method, the load torque _TL of the equation (1) is set to an accurate value corresponding to the crank angle. Cannot be obtained as. Therefore, there is a possibility that the value of the estimated angular acceleration and the actual angular acceleration deviate greatly, and control is performed based on erroneous commutation position information, resulting in step-out of the rotary electric machine 30. be.

Therefore, in the present embodiment, as described above, when the rotary electric machine 30 is reversely operated in the preparatory process, the angular acceleration is estimated by using the second estimation method. In the second estimation method, as described with reference to the equation (2), the angular acceleration α ₂ is estimated _{after setting the load torque to a constant value of max (TL).} Since such α _{2 is smaller than α 1} by the first estimation method, it is estimated as a value smaller than the actual angular acceleration. Therefore, the commutation position information of the V phase and the U phase estimated based on _{α 2 is estimated to be switched at a later timing than the actual timing.}

The present inventors, when the commutation position information is estimated to be switched at a later timing than the actual one, the step-out is higher than the case where the commutation position information is estimated to be switched at an earlier timing than the actual one. We have obtained the finding that it is relatively unlikely to occur. If the angular acceleration α ₂ is estimated as a value smaller than the actual angular acceleration as described above, even in a situation where an accurate load torque according to the crank angle cannot be grasped, each commutation position. The information is not estimated to switch earlier than it really is. Therefore, in the present embodiment, the rotary electric machine 30 can be operated in reverse without causing step-out.

In step S23 following step S22, as in step S13 of FIG. 7, the position information estimation unit 11 estimates the commutation position information for each of the W phase, the V phase, and the U phase, and the commutation timing of each phase is set. Set. The commutation timing is set by calculating the respective lengths of the periods α and β in the example of FIG. 4 using the _{angular acceleration α 2 estimated in step S22.}

In step S24 following step S23, the operation of the rotary electric machine 30 is controlled according to the commutation timing of each phase set in step S23. As a result, the reverse rotation operation of the rotary electric machine 30 started in step S21 is continuously stably continued thereafter.

In step S25 following step S24, it is determined whether or not the crank angle changed by the operation of the rotary electric machine 30 has reached the stop position. As described with reference to FIG. 5, the rotary electric machine 30 stops when the load torque that changes according to the crank angle exceeds the torque of the rotary electric machine 30. When the rotary electric machine 30 is stopped in this way, it is determined in step S25 that the stop position has been reached.

Instead of such an embodiment, for example, when the signal from the crank angle sensor 21 indicates the passage of the missing tooth, or when the signal changes by a predetermined angle after the missing tooth has passed, the crank is used. It may be determined that the corner has reached the stop position.

If it is determined in step S25 that the crank angle has not yet reached the stop position, the processes after step S22 are executed again, and the reverse rotation operation of the rotary electric machine 30 is continued. If it is determined that the crank angle has reached the stop position, the process proceeds to step S26. In step S26, the process of reversely operating the rotary electric machine 30 is stopped.

As described above, in the control device 10 according to the present embodiment, when the rotary electric machine 30 is rotated in the normal direction, the angular acceleration estimation unit 13 estimates the angular acceleration of the rotary electric machine 30 by the first estimation method, and performs a preparatory process. Therefore, when the rotary electric machine 30 is reversely operated, the angular acceleration estimation unit 13 is configured to estimate the angular acceleration of the rotary electric machine 30 by the second estimation method. As a result, even when the rotary electric machine 30 is reverse-operated in advance before the start of the internal combustion engine 20, it is possible to stably reverse-operate the rotary electric machine 30 without causing step-out.

As shown in the equations (1) and (2), the angular acceleration estimation unit 13 has the drive torque ( _TM ) generated by the rotary electric machine 30 and the load received by the rotary electric machine 30 when rotating the internal combustion engine 20. The angular acceleration of the rotary electric machine 30 is estimated based on the difference between the torque ( _TL and max ( _TL)). Further, when the angular acceleration estimation unit 13 estimates the angular acceleration α ₂ by the second estimation method, the load torque value is higher than that when _{the angular acceleration α 1} of the rotary electric machine 30 is estimated by the first estimation method. To a large value. That is, the value of the load torque is subtracted from the _{T L} in the formula (2), than _{T L} is set to a max _{(T L).} This makes it possible to estimate the angular acceleration α ₂ as a value smaller than the actual angular acceleration and realize a stable reverse rotation operation of the rotary electric machine 30.

The above max ( _TL ) is a constant value that does not change with the passage of time (which may be called a change in the crank angle). When estimating the _{angular acceleration α 2} by the equation (2) _{, max (TL} ) may be replaced with another constant value different from this. Even in such an embodiment, the same effects as those described above can be obtained.

Further, the second estimation method may be a method different from the equation (2). For example, an estimation method may be used in which a fixed value that is sufficiently smaller than _{α 1} is calculated as the value of _{α 2.} Further, an estimation method may be used in which 0 is always calculated as the above fixed value.

During the period in which the preparation process of FIG. 8 is being executed, the control device 10 can calculate the actual angular acceleration of the rotary electric machine 30 based on, for example, the cycle in which the signal from the commutation sensor 31 is switched. Therefore, if the difference between the actual angular acceleration calculated in this way and the angular acceleration α ₂ calculated in step S22 of FIG. 8 becomes too large, the difference is alleviated. , The value of the angular acceleration α ₂ may be corrected as appropriate. On the contrary, when the above difference becomes too small _{, the value of the angular acceleration α 2} may be appropriately corrected so as to increase the difference. In any case, the angular acceleration alpha ₂ values after correction, and the actual angular acceleration is smaller than the angular acceleration alpha ₁ of the values estimated by the first estimating method.

In this embodiment, as described with reference to FIG. 6, immediately after the power switch of the vehicle MV is turned on, the preparatory process for rotating the rotary electric machine 30 in the reverse direction is executed. Instead of such an aspect, the preparatory process is executed during the period from when the vehicle MV has finished running and the power switch is turned off until the power switch is turned on for the next running. May be good. As described above, the timing at which the preparatory process for rotating the rotary electric machine 30 in the reverse direction is executed may be a timing before the start of the internal combustion engine 20. At such a timing, the start of the internal combustion engine 20 is not delayed due to the execution of the preparatory process, so that the driver does not feel uncomfortable.

The present embodiment has been described above with reference to specific examples. However, the present disclosure is not limited to these specific examples. These specific examples with appropriate design changes by those skilled in the art are also included in the scope of the present disclosure as long as they have the features of the present disclosure. Each element included in each of the above-mentioned specific examples, its arrangement, conditions, a shape, and the like are not limited to those exemplified, and can be appropriately changed. The combinations of the elements included in each of the above-mentioned specific examples can be appropriately changed as long as there is no technical contradiction.

The controls and methods described in this disclosure are dedicated to one or more provided by configuring a processor and memory programmed to perform one or more functions embodied by a computer program. It may be realized by a computer. The control device and control method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor including one or more dedicated hardware logic circuits. The control device and control method described in the present disclosure comprises a combination of a processor and memory programmed to perform one or more functions and a processor including one or more hardware logic circuits. It may be realized by one or more dedicated computers. The computer program may be stored on a computer-readable non-transitional tangible recording medium as an instruction executed by the computer. The dedicated hardware logic circuit and the hardware logic circuit may be realized by a digital circuit including a plurality of logic circuits or an analog circuit.

10: Control device 11: Position information estimation unit 12: Motion control unit 13: Angular acceleration estimation unit MV: Vehicle 20: Internal combustion engine 30: Rotating electric machine 31: Commuting sensor

Claims (4)

It is a control device (10) of a vehicle (MV),
The vehicle is provided with an internal combustion engine (20) for generating a driving force for traveling and a rotary electric machine (30) for starting the internal combustion engine.
The position information estimation unit (11) for estimating the commutation position information for each of the first phase, the second phase, and the third phase in the rotary electric machine, and
An operation control unit (12) that controls the operation of the rotary electric machine based on each of the estimated commutation position information, and
The angular acceleration estimation unit (13) for estimating the angular acceleration of the rotary electric machine is provided.
The motion control unit is configured to perform a preparatory process for causing the rotary electric machine to reversely operate in advance before the internal combustion engine is started.
The position information estimation unit is
While estimating the commutation position information about the first phase based on the signal from the commutation sensor (31) provided in the rotary electric machine, while
The commutation position information for each of the second phase and the third phase is based on the angular acceleration estimated by the angular acceleration estimation unit with reference to the commutation position information for the first phase. It is an estimate,
The angular acceleration estimation unit is
When the rotary electric machine is rotated in the normal direction, the angular acceleration of the rotary electric machine is estimated by the first estimation method.
When the rotary electric machine is reversely operated for the preparatory process, the angular acceleration of the rotary electric machine is estimated by a second estimation method in which the angular acceleration value of the rotary electric machine is estimated as a smaller value than the first estimation method. A control device that estimates. The angular acceleration estimation unit is
The angular acceleration of the rotary electric machine is estimated based on the difference between the drive torque generated by the rotary electric machine and the load torque that the rotary electric machine receives when rotating the internal combustion engine.
When estimating the angular acceleration of the rotary electric machine by the second estimation method,
The control device according to claim 1, wherein the value of the load torque is set to a larger value than in the case where the angular acceleration of the rotary electric machine is estimated by the first estimation method. The angular acceleration estimation unit is
The control device according to claim 2, wherein when the angular acceleration of the rotary electric machine is estimated by the second estimation method, the value of the load torque is set to a constant value that does not change with the passage of time. The angular acceleration estimation unit is
The control device according to claim 3, wherein the operation control unit sets a maximum value that can be taken by the fluctuating load torque as the constant value when the rotary electric machine is reversely operated for the preparatory process.

Images