JP4797537B2 - Motor control device - Google Patents

Description

  The present invention relates to a motor control device.

  A motor control device is known that detects the magnetic pole position of a synchronous motor using a three-phase Hall element (see, for example, Patent Document 1).

Prior art documents related to the invention of this application include the following.
JP 2000-116175 A

  However, in the above-described conventional motor control device, the magnetic pole position is detected using the three-phase pulse output every 120 degrees from the three-phase Hall element. Detection deviation may occur. There is a problem that the drive control of the synchronous motor cannot be started smoothly due to the detection deviation of the magnetic pole position.

  Using position detection means that outputs a pulse signal corresponding to the magnetic pole position of the synchronous motor, the elapsed time from when the output signal level of the position detection means changes is counted, the magnetic pole position of the synchronous motor is calculated, and the magnetic pole position is calculated. In the motor control device that drives and controls the synchronous motor based on this, the synchronous motor is driven based on the calculated magnetic pole position after the output signal level of the position detecting means is changed for the first time by rotating the synchronous motor to rotate the synchronous motor. Start control.

  According to the present invention, the drive control of the synchronous motor can be smoothly started even if there is a detection deviation of the magnetic pole position before the output signal level of the position detecting means first changes.

  An embodiment in which the motor control device of the present invention is applied to a motor control device for a hybrid vehicle will be described. The present invention is not limited to the motor control device for a hybrid vehicle, but can be applied to an electric vehicle or a motor control device other than a vehicle.

  FIG. 1 is a diagram illustrating a configuration of a hybrid vehicle according to an embodiment. The hybrid vehicle according to this embodiment includes an engine 104 and a motor generator 105, and travels by driving force of either or both of the engine 104 and the motor generator 105. One motor generator 105 has functions of traveling drive, engine starting, regenerative braking, and power generation.

  The motor generator 105 is connected to the engine 104 via the clutch 109 to start the engine 104 and is driven by the engine 104 to generate electric power. The motor generator 105 is also connected to the transmission 106 via the clutch 110, and travels driving wheels (not shown).

  The motor generator 105 is a synchronous motor including a rotor having magnets divided and magnetized into a plurality of poles, and a stator having a plurality of drive coils and a magnetic detector arranged at a predetermined angle. In this embodiment, an example using a three-phase synchronous motor is shown. In this embodiment, an example in which a three-phase Hall element is used for the above-described magnetic detector is shown.

  The inverter 108 converts DC power of a battery (not shown) into AC power and supplies it to the motor generator 105 to generate a driving force from the motor generator 105 and reversely convert the regenerative power of the motor generator 105 into DC power. Charge the battery.

  The vehicle controller 102 calculates the required driving force of the vehicle based on the vehicle information 101 such as the vehicle speed, transmission shift position, brake pedal depression pressure, accelerator pedal depression amount, etc., and performs energy management so that the fuel consumption is minimized. The torque command value Teng of the engine 104 and the torque command value Tmg of the motor generator 105 are determined. The vehicle controller 102 also transmits start / stop commands for the engine 104 to the engine controller 103 based on the vehicle information 101, and transmits a discharge request to the motor controller 107 during shutdown (when the main key of the hybrid vehicle is off).

  Further, the vehicle controller 102 receives a clutch request from the motor controller 107 and controls opening and closing of the clutches 109 and 110. That is, when the engine is started, the clutch 109 is connected and the clutch 110 is released, and the engine 104 is driven by the motor generator 105 to start. On the other hand, at the time of shutdown, the clutches 109 and 110 are released in order to discharge the charge of a smoothing capacitor (not shown) of the inverter 108.

  The engine controller 103 starts and stops the engine 104 according to the engine start / stop command from the vehicle controller 102, and controls a throttle valve opening / closing device, a fuel injection device, and an ignition timing control device (not shown) according to the engine torque command value Teng. The output torque of the engine 104 is adjusted.

  The motor controller 107 controls the inverter 108 according to the motor generator torque command value Tmg of the vehicle controller 102 and adjusts the output torque of the motor generator 105. The motor controller 107 also receives a discharge request from the vehicle controller 102, controls the inverter 108 to flow a d-axis current to the motor generator 105, and discharges the charge of a smoothing capacitor (not shown) of the inverter 108. On the other hand, when the engine 104 is started, an opening / closing command for the clutches 109 and 110 is output to the vehicle controller 102.

  The vehicle controller 102, the engine controller 103, and the motor controller 107 each include peripheral components such as a microcomputer, ROM, RAM, and A / D converter, and exchange information via a communication network in the vehicle.

FIG. 2 is a block diagram showing a detailed configuration of the motor controller 107. The current command unit 1 has a table of two-phase DC current command values, and sets dq-axis current command values id ^* and iq ^* according to a torque command value Tmg to be described later and an electrical angular frequency ω of the motor generator 105. When a discharge request is received, the q-axis current iq ^{* is set} to zero. The current command unit 1 also outputs a request to open and close the clutches 109 and 110 to the vehicle controller 102 when the engine 104 is started and when a capacitor discharge is requested.

The current control unit 2 calculates d and q-axis voltage command values vd ^* and vq ^* for making the d and q-axis actual currents id and iq coincide with the command values id ^* and iq ^* . The two-phase / three-phase converter 3 converts the d and q-axis voltage command values vd ^* and vq ^* into the three-phase AC voltage command values vu ^* , vv ^* and vw ^* based on the magnetic pole position detection value θ of the motor generator 105. . The inverter 108 switches the DC power supply of the battery 111 by a switching element such as IGBT in accordance with the three-phase AC voltage command values vu ^* , vv ^* , vw ^* , and converts it to the three-phase AC voltages vu, vv, vw.

  The three-phase / two-phase converter 4 converts the three-phase AC actual currents iu, iv, iw of the motor generator 105 detected by the current sensors 112 to 114 into the two-phase DC actual currents id, iq based on the magnetic pole position detection value θ. To do. The magnetic pole position detector 5 detects the magnetic pole position θ of the motor generator 105 based on the pulse signal from the position sensor 115 directly connected to the rotation shaft of the motor generator 105. The motor generator electrical angular frequency detector 6 detects the electrical angular frequency ω of the motor generator 105 based on the pulse signal from the position sensor 115.

  The position sensor 115 is a three-phase Hall element arranged in a stator coil (not shown) of the motor generator 105 that is a three-phase synchronous motor, and outputs a three-phase pulse signal corresponding to the magnetic pole position of the rotor (not shown). Output.

FIG. 3 shows three-phase pulse signals U, V, and W output from the position sensor 115. The U, V, and W phase pulse signals have a width of an electrical angle of 180 degrees and are out of phase with each other by an electrical angle of 120 degrees. Therefore, the position signal of the motor generator 105 output from the position sensor 115 changes every 60 degrees of electrical angle, and the electrical angular frequency ω of the motor generator 105 is obtained by the following equation.
ω = 2π · (1/6) · (1 / (sensor signal change time every 60 degrees)) (1)

Further, the magnetic pole position θ of the motor generator 105 represents the level of the three-phase U, V, W pulse signals of the position sensor 115 as H or L, and the elapsed time from the signal change every 60 degrees of the position sensor 115 is ΔT. Then
When (U, V, W) = (H, L, H), the magnetic pole position θ is between 0 and 60 degrees,
θ = 0 + ω · ΔT · (180 / π) (2),
When (U, V, W) = (H, L, L), the magnetic pole position θ is between 60 and 120 degrees,
θ = 60 + ω · ΔT · (180 / π) (3),
When (U, V, W) = (H, H, L), the magnetic pole position θ is between 120 and 180 degrees,
θ = 120 + ω · ΔT · (180 / π) (4),
When (U, V, W) = (L, H, L), the magnetic pole position θ is between 180 and 240 degrees,
θ = 180 + ω · ΔT · (180 / π) (5),
When (U, V, W) = (L, H, H), the magnetic pole position θ is between 240 and 300 degrees,
θ = 240 + ω · ΔT · (180 / π) (6),
When (U, V, W) = (L, L, H), the magnetic pole position θ is between 300 and 0 degrees,
θ = 300 + ω · ΔT · (180 / π) (7)
It becomes.

  The elapsed time ΔT after the change of the output signal level of the position sensor 115 is measured using the clock of the microcomputer of the motor controller 107. When the motor generator 105 is rotating, the magnetic pole position θ can be accurately detected by the above equations (2) to (7) by measuring the elapsed time ΔT from the signal level change every 60 degrees of the position sensor 115. Can do. However, when the motor generator 105 is stopped, the magnetic pole position θ is 0 to 60 degrees, 60 to 120 degrees, 120 to 120 based on the level of the three-phase pulse signal (U, V, W) of the position sensor 115. Although it is possible to detect the range of 180 degrees, 180 to 240 degrees, 240 to 300 degrees, and 300 to 360 degrees, it is impossible to detect a detailed position within the detection range. That is, when the motor generator 105 is stopped, there is a magnetic pole position detection deviation in the range of 0 to 60 degrees.

  FIG. 4 is a diagram illustrating a change in output torque with respect to magnetic pole position detection deviation when the motor generator is activated. In FIG. 4, the current phase [degree] on the horizontal axis is the phase angle between the dq-axis currents id and iq shown in FIG. When the correct magnetic pole position of the motor generator 105 is detected and the dq axis currents id and iq are supplied according to the current command value, the maximum torque of the starting torque output point indicated by the black circle in the figure is generated. If there is a deviation in detection of the B magnetic pole position, the output torque may be reduced to a maximum of A and B points. For this reason, when the engine is started at an extremely low temperature, the output torque of the motor generator 105 becomes smaller than the static torque of the engine 103 and the engine cannot be started. Although a current map including a current that compensates for the torque drop corresponding to the magnetic pole position detection deviation may be created and used, it is not efficient.

  In addition, the same problem as that at the time of starting the engine described above also occurs when starting the motor travel in the hybrid vehicle. That is, when driving by driving the drive wheels by the motor generator 105 and the output torque of the motor generator 105 decreases due to the detection error of the magnetic pole position, the vehicle travels by overcoming running resistance such as a gradient road and high load. Can not be made.

  FIG. 5 is a diagram showing a change in the output torque with respect to the magnetic pole position detection deviation when the charge of the inverter smoothing capacitor is discharged to the motor generator 105 at the time of system shutdown. In FIG. 5, the current phase [degree] on the horizontal axis is the phase angle between the dq-axis currents id and iq shown in FIG. When the correct magnetic pole position of the motor generator 105 is detected and the dq-axis currents id and iq are supplied according to the current command value, the discharge can be performed at the zero torque point indicated by the black circle in the figure, but the magnetic pole positions of C to D If there is a discrepancy, there is a possibility of generating maximum C and D point output torque. Therefore, when the clutches 109 and 110 at both ends of the motor generator 105 are released, the motor generator 105 rotates and rises with no load, giving the driver a sense of incongruity.

In this embodiment, in order to solve the problem caused by the magnetic pole position detection deviation described above, the motor controller 7 executes the control program shown in FIG. 7 to generate torque output and capacitor discharge for engine start and vehicle driving. Do. In step 1, it is confirmed whether there is a discharge request from the vehicle controller 102 or a torque output request. In the case of a torque output request, the process proceeds to Step 2, and the minimum value is obtained from the dq axis current command value table stored in advance by mapping based on the torque command value Tmg from the vehicle controller 102 and the electrical angular frequency ω of the motor generator 105. The dq-axis current command values id ^* and iq ^* that generate the desired torque Tmg with current are retrieved and output. Here, the torque command value Tmg is a target torque for starting the engine 104 when the engine is started, and is a target torque for driving drive wheels (not shown) during driving of the vehicle.

  In step 3, it is determined whether or not the absolute value of the electrical angular frequency ω of the motor generator 105 is greater than a predetermined value α. Here, the predetermined value α is the calculation formula of the magnetic pole position θ in the above formulas (2) to (7), and the correction term ω · ΔT · (180 / π) of the electrical angular frequency ω is “ Let ω be 0 ″. When the absolute value of the electrical angular frequency ω is larger than the predetermined value α, the correction term ω · ΔT · (180 / π) in the above equations (2) to (7) does not become 0, so that the magnetic pole position θ is accurately calculated. In step 7, the clutch connection request is transmitted to the vehicle controller 102. At this time, in the case of torque output for starting the engine, a request for connection of the clutch 109 is output, and in the case of torque output for driving driving, a request for connection of the clutch 110 is output.

  On the other hand, when it is determined in step 3 that the absolute value of the electrical angular frequency ω of the motor generator 105 is equal to or less than the predetermined value α, the correction term ω · ΔT · (180 / π) in the above equations (2) to (7) is Since it becomes 0, the magnetic pole position θ cannot be calculated. Accordingly, the process proceeds to step 4 to determine whether or not the output signal level of the position sensor 115 has changed, or whether or not there has already been a signal level change and a clutch connection request has been issued.

  When the signal level of the position sensor 115 has changed, the motor generator 105 has rotated to the signal level change point of the position sensor 115, so there is no position detection deviation, and the target torque can be generated based on the accurate magnetic pole position θ. Further, if the signal level change of the position sensor 115 has already occurred at the time of execution of this control program up to the previous time and a clutch connection request has been issued, of course, the target torque can be generated based on the accurate magnetic pole position θ. In such a case, the process proceeds to step 6 to transmit a clutch 109 connection request to the vehicle controller 102. At this time, in the case of torque output for starting the engine, a request for connection of the clutch 109 is output, and in the case of torque output for driving driving, a request for connection of the clutch 110 is output.

  If there is no change in the signal level of the position sensor 115 and no clutch connection request is issued, there is a possibility that a position detection deviation of 0 to 60 degrees has occurred. Output to. Here, the half-clutch is a half-connected state that is not completely connected, and is a state in which the clutch rotates while sliding. The vehicle controller 102 rotates the motor generator 105 with a torque (β · Tmg) obtained by multiplying the motor generator torque command value Tmg by a torque reduction rate β when the magnetic pole detection position of the motor generator 105 is shifted by a maximum of 60 degrees. The clutch 109 is controlled so that a half clutch amount (half connection amount) can be obtained. In the case of torque output for starting the engine, a half-clutch request for the clutch 109 is output, and in the case of torque output for driving, a half-clutch request for the clutch 110 is output.

  As a result, even if a position detection deviation occurs, the motor generator 105 can be rotated, and the signal level change point of the position sensor 115 is passed during the rotation. When the signal level of the position sensor 115 has changed, the process proceeds from step 4 to step 6 and a clutch connection request is transmitted to the vehicle controller 102 as described above. At this time, in the case of torque output for starting the engine, a request for connection of the clutch 109 is output, and in the case of torque output for driving driving, a request for connection of the clutch 110 is output.

  When a capacitor discharge request is received from the vehicle controller 102 in step 1, the process proceeds to step 8 in order to prevent the motor generator 105 from rotating due to the magnetic pole position detection deviation and giving an impact to the vehicle. Is sent to the vehicle controller 102.

In step 9, it is determined whether or not the output signal level of the position sensor 115 has changed, or whether or not the signal level has already changed and a discharge current command has been issued to the inverter 108. When the signal level of the position sensor 115 changes, the motor generator 105 rotates to the signal level change point of the position sensor 115, so that there is no detection deviation of the magnetic pole position, and torque is not generated based on the accurate magnetic pole position θ. Capacitor discharge current can flow. If the signal level change of the position sensor 115 has already occurred at the time of execution of this control program up to the previous time and the discharge current command is issued, of course, the capacitor discharge current can be generated without generating torque based on the accurate magnetic pole position θ. Can flow. In such a case, the process proceeds to step 11 to command discharge current id ^* = id2, iq ^* = 0 for the d-axis only. As a result, it is possible to prevent the motor generator 105 from rotating during the capacitor discharge of the inverter 108 and causing the passenger to feel uncomfortable.

On the other hand, when there is no change in the signal level of the position sensor 115 and no discharge current command is issued, a position detection deviation of 0 to 60 degrees may occur. Until the motor generator 105 is rotated. That is, in step 10, assuming that a position detection deviation of 60 degrees at the maximum has occurred, the motor generator 105 searches the current map with the torque command value Tmg_B and ω = 0 that rotate 60 degrees within the predetermined time T1, Set id ^* = id1, iq ^* = iq1. Here, the predetermined time T1 is a time set in advance to prevent the motor generator 105 from rotating unnecessarily beyond 60 degrees, and the torque command value Tmg_B for rotating the motor generator 105 by 60 degrees within the predetermined time T1. Is set in advance by experiments or the like.

As a result, the motor generator 105 rotates 60 degrees at time T1, and passes the signal level change point of the position sensor 115 during the rotation. When the signal level of the position sensor 115 is changed, the process proceeds from step 9 to step 11 to command the d-axis discharge current id ^* = id2, iq ^* = 0 as described above.

  Thus, according to one embodiment, the position sensor 115 that outputs a pulse signal corresponding to the magnetic pole position of the motor generator 105 that is a synchronous motor is used, and the process after the output signal level of the position sensor 115 changes. In a motor control device that counts the time ΔT to calculate the magnetic pole position of the motor generator 105 and drives and controls the motor generator 105 based on the magnetic pole position, a predetermined current is passed through the motor generator 105 to rotate it, and the position sensor 115 Since the drive control of the motor generator 105 based on the calculated magnetic pole position is started after the output signal level has changed for the first time, the magnetic pole position is not changed until the output signal level of the position sensor 115 changes for the first time. Even if there is a detection error, motor generator 1 5 of the drive control can be started smoothly.

  Further, according to one embodiment, when the engine 104 is started by the motor generator 105 that is a synchronous motor, the clutch 109 is in a semi-connected state, and the motor generator 105 is rotated by supplying a current according to the target torque, After the output signal level of the position sensor 115 changes for the first time, the clutch 109 is completely connected and the drive control of the motor generator 105 based on the magnetic pole position calculated by the magnetic pole position detector 5 is started. Since torque is output, even if there is a deviation in detection of the magnetic pole position before the output signal level of the position sensor 115 changes for the first time, the engine 104 in a state where the static friction torque is large in a low-temperature environment is reliably ensured. Can be started.

  Furthermore, according to one embodiment, when driving wheels are driven by the motor generator 105, which is a synchronous motor, to start driving the vehicle, the clutch 110 is set in a semi-connected state and the motor generator 105 is subjected to a target torque. After the first change in the output signal level of the position sensor 115, the clutch 110 is completely connected and the drive control of the motor generator 105 based on the magnetic pole position calculated by the magnetic pole position detector 5 is performed. Since the target torque is output from the motor generator 105, even if there is a misdetection of the magnetic pole position before the output signal level of the position sensor 115 changes for the first time, It is possible to drive the vehicle overcoming a high load.

  Furthermore, according to one embodiment, when discharging the power supply smoothing capacitor of the inverter 108, the clutch 110 is released and the motor generator 105 is rotated by supplying a current corresponding to a predetermined torque to the position sensor 115. After the output signal level has changed for the first time, the drive control of the motor generator 105 based on the magnetic pole position calculated by the magnetic pole position detector 5 is started, and the d-axis current is caused to flow through the motor generator 105. Therefore, the position sensor 115 Even if there is a detection deviation of the magnetic pole position until the output signal level first changes, it is possible to suppress the rotation increase of the motor generator 105 during capacitor discharge, and to prevent the passenger from feeling uncomfortable.

<< Modification of Embodiment of Invention >>
FIG. 8 is a diagram illustrating a configuration of a hybrid vehicle according to a modification of the embodiment. In addition, the same code | symbol is attached | subjected with respect to the apparatus similar to the apparatus shown in FIG. 1, and it demonstrates centering around difference. In this modification, an auxiliary machine 122 is connected to an output shaft of the motor generator 105 via a power transmission mechanism 120 such as a belt or a chain and a clutch 121. In order to suppress the impact on the vehicle and the rotation increase of the motor generator 105 during the capacitor discharge of the inverter 108, the clutch 121 is connected and the auxiliary machine 122 is connected to the motor generator 105 to increase the load on the motor generator 105.

FIG. 9 is a flowchart showing a current control program according to a modification of the embodiment. Note that steps that perform the same processing as the steps shown in FIG. 7 are given the same step numbers, and the differences will be mainly described. When a capacitor discharge request is received from the vehicle controller 102 in step 1, a release request for the clutches 109 and 110 and a connection request for the clutch 121 are output to the vehicle controller 102 in step 8. As a result, the motor generator 105 enters a load state. In the subsequent step 9, discharge current id ^* = id2, iq ^* = 0 is set regardless of the presence or absence of position detection deviation. Even if torque is generated in the motor generator 105 due to the position detection error of the position sensor 115, the auxiliary machine 122 absorbs the rotation of the motor generator 105, so that the rotation of the motor generator 105 is suppressed and it is possible to prevent the passenger from feeling uncomfortable.

  Thus, according to the modification of the embodiment, when discharging the power supply smoothing capacitor of the inverter 108, the clutch 110 is released and the clutch 121 is connected so that the d-axis current flows through the motor generator 105. Therefore, even if there is a detection deviation of the magnetic pole position before the output signal level of the position sensor 115 changes for the first time, the auxiliary machine 122 becomes a load on the motor generator 105 during capacitor discharge, and the rotation increase is suppressed. , Can prevent the passengers from feeling uncomfortable.

  The correspondence between the constituent elements of the claims and the constituent elements of the embodiment is as follows. That is, the position sensor 115 is the position detection means, the motor controller 107 is the timing means and the drive control means, the magnetic pole position detection unit 5 is the position calculation means, the clutch 109 is the first clutch, the clutch 110 is the second clutch, 121 each constitutes a third clutch. The above description is merely an example, and when interpreting the invention, the correspondence between the items described in the above embodiment and the items described in the claims is not limited or restricted.

It is a figure showing composition of a hybrid vehicle of one embodiment. It is a figure which shows the structure of the motor controller of one embodiment. It is a figure which shows the output signal of the position sensor using a three-phase Hall element. It is a figure which shows the mode of the torque reduction by the position detection shift | offset | difference of a position sensor. It is a figure which shows the mode of the torque generation by the position detection shift | offset | difference of a position sensor. It is a figure which shows the phase relationship of dq axis current id and iq. It is a flowchart which shows the electric current control program of one Embodiment. It is a figure which shows the structure of the hybrid vehicle of the modification of one embodiment. It is a flowchart which shows the current control program of the modification of one Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Current command part 2 Current control part 3 Two phase three phase conversion part 4 Three phase two phase conversion part 5 Magnetic pole position detection part 6 Motor generator electrical angular frequency detection part 102 Vehicle controller 104 Engine 105 Motor generator 107 Motor controller 108 Inverter 109, 110, 121 Clutch 111 Battery 112-114 Current sensor 115 Position sensor 120 Power transmission mechanism 122 Auxiliary machine

Claims (3)

Position detecting means for outputting a pulse signal corresponding to the magnetic pole position of the synchronous motor;
Time measuring means for measuring the elapsed time since the output signal level of the position detecting means is changed;
Position calculating means for calculating the magnetic pole position of the synchronous motor based on the time measured by the time measuring means;
A motor control device comprising drive control means for driving and controlling the synchronous motor based on the magnetic pole position calculated by the position calculation means,
The synchronous motor is connected to a driving wheel of the vehicle via a second clutch;
When the drive control means discharges the power source smoothing capacitor of the built-in inverter, the drive control means releases the second clutch and causes the synchronous motor to rotate by passing a current corresponding to a predetermined torque, and outputs the position detection means. After the signal level has changed for the first time, drive control of the synchronous motor based on the magnetic pole position calculated by the position calculation means is started, and a d-axis current is allowed to flow through the synchronous motor. . The motor control device according to claim 1 ,
The motor control device according to claim 1, wherein the predetermined torque is a torque by which the synchronous motor rotates by a predetermined angle within a predetermined time. The motor control device according to claim 1,
The synchronous motor is connected to the driving wheel of the vehicle via the second clutch, and is connected to the vehicle-mounted auxiliary machine via the third clutch,
The drive control means releases the second clutch and connects the third clutch to flow only the d-axis current to the synchronous motor when discharging the power smoothing capacitor of the built-in inverter. Motor control device.

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