JP6680152B2 - Control device for rotating electric machine - Google Patents

Description

  The present invention relates to a control device applied to a rotary electric machine including a rotor having field windings and a stator having armature windings.

  As a control device of this kind, as seen in Patent Document 1 below, while controlling the field current flowing from the DC power supply to the field winding, the power of the DC power supply is converted into AC power to generate an armature winding. It is known to supply power to. Specifically, in this control device, at the time of starting the internal combustion engine, at the same time when the field current starts to flow in the field winding or immediately before the field current starts to flow, the magnetic flux generated by flowing the field current is The armature winding is energized from the power converter so that magnetic flux in the opposite direction is generated. As a result, torque is quickly generated in the rotating electric machine.

JP, 2004-144019, A

  Here, in the control method described in Patent Document 1, it is not always possible to quickly raise the torque generated by the rotating electric machine to the target torque after the field current is started to flow. For this reason, there is still room for improvement in the technology for improving the response of the torque generated by the wound-field type electric rotating machine.

  It is a main object of the present invention to provide a controller for a rotary electric machine that can improve the response of the torque generated by the rotary electric machine.

  INDUSTRIAL APPLICATION This invention is applied to the rotary electric machine (10) provided with the rotor (12) which has a field winding (11), and the stator (13) which has an armature winding (13U-13W). In the present invention, in the rotating coordinate system of the rotating electric machine, a current flowing through the armature winding along the direction of a field magnetic flux generated by flowing a field current through the field winding is defined as a d-axis current. , The current flowing through the armature winding in the direction orthogonal to the d-axis current is defined as the q-axis current. Further, the sign of the d-axis current flowing in the direction of canceling the field magnetic flux is defined as negative, and the sign of the q-axis current when the rotating electric machine generates torque is defined as positive. The present invention relates to a field control section (40) for controlling the field current, and a period from when the field current starts to flow by the field control section until the field current increases and reaches a field target current. An electric machine that controls the current flowing through the armature winding in order to change the d-axis current and to flow a positive q-axis current on the condition that the changing direction of the d-axis current is only in the negative direction. A child controller (40).

  In the present invention, the d and q axis currents and the signs of the d and q axis currents are defined as described above. Here, by changing the d-axis current in the canceling direction of the field magnetic flux in the middle of the period from when the field current begins to flow to when the field current increases and reaches the field target current, The time required for the magnetic current to reach the field target current can be shortened. However, if the change direction of the d-axis current is in the positive direction during the process of changing the d-axis current, the self-inductance of the field winding increases in the positive direction, and the field current is It will decrease. As a result, even if a torque is generated in the rotating electric machine by flowing a positive q-axis current, the responsiveness of the generated torque will deteriorate.

  Therefore, in the present invention, the condition that the changing direction of the d-axis current is only in the negative direction in the middle of the period from when the field current starts flowing to when the field current increases and reaches the field target current In order to change the d-axis current and flow a positive q-axis current, the current flowing through the armature winding is controlled. Therefore, in the middle of the process of changing the d-axis current, it is possible to prevent the process in which the changing direction of the d-axis current is in the positive direction from being included, and it is possible to prevent the field current from decreasing. Thereby, the responsiveness of the torque generated by the rotating electric machine can be improved.

1 is an overall configuration diagram of an in-vehicle control system according to a first embodiment. The block diagram which shows the torque control process of a control apparatus. The flowchart which shows the procedure of an engine starting process. The figure which shows the constant current circle drawn by a current vector in a dq coordinate system. The characteristic view which shows the relationship between the d-axis efficiency current and field current which specify the maximum efficiency point. The figure which shows the equivalent circuit of a field winding. The time chart which shows an example of the engine starting processing concerning a 1st embodiment and related art 1. The time chart which shows an example of the engine starting processing concerning a 1st embodiment and related art 2. The figure which shows the maximum efficiency point set to the positive side of d-axis. The flowchart which shows the procedure of the engine starting process which concerns on 2nd Embodiment. The figure which shows the change method of d, q-axis current which concerns on other embodiment. The figure which shows the change method of d, q-axis current which concerns on other embodiment.

(First embodiment)
Hereinafter, a first embodiment in which the control device according to the present invention is applied to a vehicle including an engine as a vehicle-mounted main unit will be described with reference to the drawings.

  As shown in FIG. 1, the vehicle includes a rotating electric machine 10 and an engine 20. The rotary electric machine 10 is of a winding field type, and specifically is a winding field type synchronous machine having three-phase windings. In this embodiment, an ISG (Integrated Starter Generator) in which the functions of the starter and the alternator are integrated is used as the rotary electric machine 10. Particularly, in the present embodiment, in addition to the initial start of the engine 20, the engine 20 is automatically stopped when a predetermined automatic stop condition is satisfied, and then the engine 20 is automatically stopped when a predetermined restart condition is satisfied. The rotating electric machine 10 also functions as a starter when executing the idling stop function of restarting the rotating electric machine.

  The rotor 12 that constitutes the rotary electric machine 10 includes the field winding 11, and is capable of transmitting power to the output shaft 20a of the engine 20. In the present embodiment, the rotor 12 is mechanically connected to the output shaft 20a via the belt 21.

  A U-phase winding 13U, a V-phase winding 13V, and a W-phase winding 13W are wound as armature windings on the stator 13 that constitutes the rotating electric machine.

  The vehicle includes an inverter INV and a battery 22 that is a DC power supply. The rotary electric machine 10 and the battery 22 are electrically connected to the inverter INV.

  The inverter INV includes three sets of U, V, W-phase upper arm switches SUp, SVp, SWp and U, V, W-phase lower arm switches SUn, SVn, SWn connected in series. The first end of the U-phase winding 13U is connected to the connection point of the U-phase upper and lower arm switches SUp and SUn. The first end of the V-phase winding 13V is connected to the connection point of the V-phase upper and lower arm switches SVp and SVn. The first end of the W-phase winding 13W is connected to the connection point of the W-phase upper and lower arm switches SWp and SWn. The second ends of the U-phase winding 13U, the V-phase winding 13V, and the W-phase winding 13W are connected at a neutral point.

  In this embodiment, N-channel MOSFETs are used as the switches SUp to SWn. The diodes DUp to DWn are connected in antiparallel to the switches SUp to SWn, respectively. The diodes DUp to DWn may be body diodes of the switches SUp to SWn. Further, each of the switches SUp to SWn is not limited to the N-channel MOSFET and may be, for example, an IGBT.

  The positive terminal of the battery 22 is connected to the drain, which is the high-potential side terminal of each of the upper arm switches SUp to SWp. The negative terminal of the battery 22 is connected to the source, which is a low-potential side terminal of each of the lower arm switches SUn to SWn.

  The vehicle includes a field circuit 36. A DC voltage can be applied to the field winding 11 by the field circuit 36. The field circuit 36 controls the field current flowing through the field winding 11 to the field target current by adjusting the DC voltage applied to the field winding 11.

  The vehicle includes a rotation angle detector 30, a voltage detector 31, a field current detector 32, and a phase current detector 33. The rotation angle detection unit 30 detects the electrical angle of the rotary electric machine 10. The voltage detection unit 31 detects the output voltage of the battery 22 as the power supply voltage VINV of the inverter INV. The field current detector 32 detects the field current flowing through the field winding 11. The phase current detector 33 detects a current for at least two phases among the currents flowing through the phase windings 13U to 13W. As the rotation angle detection unit 30, for example, a resolver can be used. Further, as the field current detection unit 32 and the phase current detection unit 33, for example, one having a current transformer or a resistor can be used.

  The vehicle includes a control device 40. The control device 40 takes in the detection values of the various detection units. The control device 40 includes a CPU and a memory as a storage unit, and the CPU executes a program stored in the memory. The control device 40 generates and outputs an operation signal for operating the inverter INV based on the detection values of various detection units in order to control the torque of the rotary electric machine 10 to the target torque Trq *.

  Control device 40 turns on / off each switch SUp-SWn so that the command current for achieving target torque Trq * and the current flowing through each phase winding of rotating electric machine 10 match. In FIG. 1, signals for operating the switches SUp to SWn of the inverter INV are shown as operation signals gUp to gWn. The field circuit 36 may be built in the control device 40 or external to the control device 40.

  Subsequently, the torque control of the rotary electric machine 10 executed by the control device 40 will be described with reference to FIG. In the present embodiment, the control device 40 includes a “field control unit” and an “armature control unit”.

  The target current setting unit 40a sets d, q-axis target currents Id *, Iq *, which are current command values of the rotating coordinate system (dq coordinate system) of the rotary electric machine 10, based on the target torque Trq *. The d-axis is defined as a direction along the direction of the field magnetic flux generated by passing a field current through the field winding 11. The q axis is defined in the direction orthogonal to the d axis.

  The two-phase conversion unit 40b calculates the U, V, and W phase currents in the fixed coordinate system based on the electrical angle θ detected by the rotation angle detection unit 30 and the phase current detected by the phase current detection unit 33. It is converted into a d-axis current Idr and a q-axis current Iqr in the dq coordinate system.

  The d-axis deviation calculation unit 40c subtracts the d-axis current Idr output from the two-phase conversion unit 40b from the d-axis target current Id * output from the target current setting unit 40a to obtain the d-axis current deviation ΔId. calculate. The q-axis deviation calculation unit 40d subtracts the q-axis current Iqr output from the two-phase conversion unit 40b from the q-axis target current Iq * output from the target current setting unit 40a to obtain the q-axis current deviation ΔIq. calculate.

  The d-axis controller 40e calculates the d-axis command voltage Vd * as an operation amount for feedback controlling the d-axis current Idr to the d-axis target current Id * based on the d-axis current deviation ΔId. In the present embodiment, the d-axis controller 40e calculates the d-axis command voltage Vd * by proportional-plus-integral control based on the d-axis current deviation ΔId. The q-axis controller 40f calculates the q-axis command voltage Vq * as an operation amount for feedback-controlling the q-axis current Iqr to the q-axis target current Iq * based on the q-axis current deviation ΔIq. In the present embodiment, the q-axis controller 40f calculates the q-axis command voltage Vq * by proportional-plus-integral control based on the q-axis current deviation ΔIq.

  The three-phase conversion unit 40g converts the d, q-axis command voltages Vd *, Vq * into three-phase command voltages VU *, VV *, VW * in the fixed coordinate system based on the electrical angle θ. The modulator 40h generates operation signals gUp to gWn for setting the phase voltages of the inverter INV to the command voltages VU *, VV *, VW *. In the present embodiment, by the triangular wave PWM processing based on the magnitude comparison between the signal in which the command voltages VU *, VV *, VW * are standardized by the power supply voltage VINV detected by the voltage detection unit 31 and the carrier signal such as the triangular wave signal. , Operation signals gUp to gWn are generated. The modulator 40h outputs the generated operation signals gUp to gWn to the inverter INV. As a result, a sinusoidal current having a phase difference of 120 degrees in electrical angle flows through each of the phase windings 13U to 13W.

  The field deviation calculation unit 40i calculates the field current deviation ΔIf by subtracting the field target current If * from the field current Ifr detected by the field current detection unit 32.

  The field controller 40j is a command value of a DC voltage applied to the field winding 11 as an operation amount for feedback controlling the field current Ifr to the field target current If * based on the field current deviation ΔIf. The field command voltage Vf is calculated. In the present embodiment, the field controller 40j calculates the field command voltage Vf by proportional-plus-integral control based on the field current deviation ΔIf. The field circuit 36 is operated to apply the field command voltage Vf to the field winding 11.

  Subsequently, FIG. 3 shows a procedure of an engine starting process according to the present embodiment. This processing is repeatedly executed by the control device 40, for example, in a predetermined processing cycle.

  In this series of processes, first, in step S10, it is determined whether a start command has been input. Here, the start command is a command that causes the rotary electric machine 10 to generate torque in order to apply initial rotation to the output shaft 20a and start the engine 20. The start command is input not only when the rotation of the rotor 12 is stopped but also when the rotor 12 is rotating.

  When an affirmative decision is made in step S10, the field target current If * is raised stepwise to a value larger than 0, and the routine proceeds to step S12. In step S12, the d-axis target current Id * is set to the d-axis positive side maximum value Idmax which is the maximum value of the d-axis current in the positive direction. As a result, the d-axis target current Id * is changed in the positive direction at the same time when the field current is started to flow. In step S12, the q-axis target current Iq * is set to 0. Since the q-axis target current Iq * is set to 0, the rotary electric machine 10 does not generate torque.

  The operating point in the dq coordinate system defined by the d and q axis currents set in step S12 will be referred to as the initial operating point. Further, the d-axis positive side maximum value Idmax is set to a maximum current value that does not reduce the reliability of the rotating electrical machine 10.

  In the following step S14, the d-axis efficiency current Ide and the q-axis efficiency current Iqe are calculated based on the field target current If *. The d-axis efficiency current Ide and the q-axis efficiency current Iqe are currents that define the maximum efficiency point at which the torque generated by the rotary electric machine 10 per unit amplitude of the current vector Ivtr flowing through the rotary electric machine 10 becomes maximum in the dq coordinate system. . In the present embodiment, the maximum efficiency point exists on the constant current circle SI that is the locus drawn by the current vector Ivtr when the amplitude of the current vector Ivtr has its maximum value, as shown in FIG. In the present embodiment, the maximum value of the amplitude of the current vector Ivtr is equal to the d-axis positive side maximum value Idmax. It should be noted that in the present embodiment, the phase β of the current vector Ivtr is defined as a positive direction in which it rotates counterclockwise with respect to the positive d axis.

  In the present embodiment, the q-axis efficiency current Iqe that defines the maximum efficiency point is a positive value. Further, as shown in FIG. 5, the d-axis efficiency current Ide that defines the maximum efficiency point has a characteristic that it shifts to the positive side of the d-axis as the field target current If * increases. In the low current region where the field target current If * is equal to or lower than the predetermined current, the d-axis efficiency current Ide has a negative value. This is because when the field current is small and magnetic saturation does not occur, the torque Trq generated by the rotary electric machine 10 becomes maximum when the phase β of the current vector Ivtr becomes 110 to 115 degrees, for example. On the other hand, in the large current region where the field target current If * is larger than the predetermined current, the d-axis efficiency current Ide has a positive value. This is because when the field current is large and magnetic saturation occurs, the torque Trq generated by the rotary electric machine 10 becomes maximum when the phase β of the current vector Ivtr becomes less than 90 degrees, for example.

  In the present embodiment, the d, q-axis efficiency currents Ide, Iqe are calculated using map information in which the d, q-axis efficiency currents Ide, Iqe are associated with the field target current If *. This map information is stored in the memory as the current information storage unit of the control device 40. Note that in the present embodiment, the process of step S14 corresponds to the "current calculation unit".

  Returning to the explanation of FIG. 3 described above, in the subsequent step S16, the field current increases when it is assumed that the actual operating point is changed from the initial operating point set in step S12 to the maximum efficiency point set in step S14. Predict the amount ΔF. Specifically, the increase amount ΔF is the increase amount of the field current Ifr in the period from the current processing cycle to the next processing cycle, assuming that the actual operating point is changed. In the present embodiment, the process of step S16 corresponds to the “prediction unit”.

  In the present embodiment, the increase amount ΔF is predicted using the following equations (eq1) to (eq3).

上式（ｅｑ１）において、「Ｌｆ」は界磁巻線１１の自己インダクタンスを示し、「Ｒｆ」は界磁巻線１１の巻線抵抗を示し、「Ｔｓ」は制御装置４０の処理周期（処理タイミングの時間間隔）を示し、「Ｖｐｌ」はｄ軸電流と界磁電流との干渉項を示す。また上式（ｅｑ２）において、「Ｍｆ」は各相巻線１３Ｕ〜１３Ｗと界磁巻線１１とのｄ軸上における相互インダクタンスを示す。上式（ｅｑ２），（ｅｑ３）のΔＤは、実際の動作点を初期動作点から最高効率点まで変化させた場合におけるｄ軸目標電流Ｉｄ＊の変化量を示す。なお上式（ｅｑ１）において、Ｉｆｒ［ｋ］は、現在の処理周期における界磁電流を示す。

In the above equation (eq1), “Lf” indicates the self-inductance of the field winding 11, “Rf” indicates the winding resistance of the field winding 11, and “Ts” indicates the processing cycle (processing) of the control device 40. (Time interval of timing), and “Vpl” indicates an interference term between the d-axis current and the field current. In the above equation (eq2), "Mf" represents the mutual inductance on the d-axis between the phase windings 13U to 13W and the field winding 11. ΔD in the above equations (eq2) and (eq3) indicates the amount of change in the d-axis target current Id * when the actual operating point is changed from the initial operating point to the maximum efficiency point. In the above equation (eq1), Ifr [k] represents the field current in the current processing cycle.

  The above equation (eq1) shows that the interference term Vpl can be increased as a positive value and the field current Ifr can be increased by changing the d-axis current in the negative direction. The above equation (eq1) is a model equation based on the voltage equation of the field winding 11. More specifically, the above equation (eq1) is derived by discretizing the voltage equation of the following equation (eq4) by the backward difference. In the following expression (eq4), “s” indicates a Laplace operator (differential operator). The equivalent circuit of the field winding 11 is shown in FIG.

続くステップＳ１８では、現在の処理周期における界磁目標電流Ｉｆ＊から、現在の処理周期における界磁電流Ｉｆｒを減算した値である界磁電流偏差ΔＩｆを算出する。そして、算出した界磁電流偏差ΔＩｆが、ステップＳ１６で予測した増加量ΔＦ以下であるか否かを判定する。この処理は、界磁電流を流し始めた後、次回の処理周期において負方向へのｄ軸電流の増加を完了させたと仮定した場合に、次回の処理周期において界磁電流が界磁目標電流Ｉｆ＊に到達するか否かを判断するための処理である。なお本実施形態において、ステップＳ１８の処理が「到達判定部」に相当する。

In a succeeding step S18, a field current deviation ΔIf which is a value obtained by subtracting the field current Ifr in the current processing cycle from the field target current If * in the current processing cycle is calculated. Then, it is determined whether or not the calculated field current deviation ΔIf is less than or equal to the increase amount ΔF predicted in step S16. In this process, after assuming that the increase of the d-axis current in the negative direction has been completed in the next process cycle after the flow of the field current is started, the field current becomes the field target current If in the next process cycle. This is a process for determining whether or not to reach *. In the present embodiment, the process of step S18 corresponds to the "arrival determination unit".

  When a negative determination is made in step S18, the process returns to step S16. On the other hand, when an affirmative determination is made in step S18, it is determined that the next processing cycle will be reached, and the process proceeds to step S20. In step S20, the d and q-axis currents are changed so as to change the actual operating point from the initial operating point to the maximum efficiency point, provided that the changing direction of the d-axis target current Id * is set only in the negative direction. Particularly, in the present embodiment, the actual operating point is changed from the initial operating point to the maximum efficiency point through the constant current circle SI drawn by the current vector Ivtr. As a result, the torque generated by the rotary electric machine 10 can be quickly raised.

  By the process of step S20, a positive q-axis current starts to flow in each phase winding 13U to 13W, so that the rotor 12 starts to rotate. As a result, the output shaft 20a is given initial rotation, and the combustion control of the engine 20 including the fuel injection control is performed, whereby the start of the engine 20 is completed thereafter.

  The engine starting process according to the present embodiment will be described with reference to FIG. 7.

  As shown in the figure, in the present embodiment, the d-axis target current Id * is set to the d-axis positive side maximum value Idmax by inputting the start command of the engine 20 to the control device 40, and the q-axis target current Iq. * Is set to 0. Further, when the start command is input to the control device 40, the field target current If * is set, and the field current Ifr starts to increase.

  After that, at time t1, it is determined that the field current deviation ΔIf is equal to or less than the predicted increase amount ΔF, so that the d-axis target current Id * changes from the d-axis positive side maximum value Idmax toward the d-axis efficiency current Ide. As it starts, the q-axis target current Iq * starts to change from 0 to the q-axis efficiency current Iqe. As a result, the field current Ifr rapidly rises to the field target current If *.

  The actual operating point changes from the initial operating point to the maximum efficiency point on the constant current circle SI drawn by the current vector Ivtr. At this time, the d-axis target current Id * changes so that its changing direction is only in the negative direction. Further, the q-axis target current Iq * rises from 0 to reach the q-axis positive side maximum value Iqmax (= Idmax) which is the maximum value of the q-axis current in the positive direction, and then moves toward the q-axis efficiency current Iqe. Decrease. As a result, the torque generated by the rotary electric machine 10 can be quickly raised without reducing the field current. As a result, the time from the input of the start command to the completion of the start of the engine 20 can be shortened.

  Here, FIG. 7 also shows the engine starting process according to Related Art 1. Hereinafter, this technique will be described.

  In Related Art 1, the d-axis target current Id * starts to change in the negative direction from 0 by the input of the start command of the engine 20 to the control device 40, and the q-axis target current Iq * remains 0. . Further, when the start command is input to the control device 40, the field target current If * is set and the field current starts to increase. After that, at time tA, the d-axis target current Id * becomes the d-axis negative side maximum value −Idmax which is the maximum value of the d-axis current in the negative direction.

  After that, at time tB, the field current Ifr reaches the field target current If *, so that the q-axis target current Iq * starts to increase from 0 in the positive direction in order to generate torque in the rotary electric machine 10. However, since the d-axis target current Id * is set to the d-axis negative side maximum value −Idmax, to change the actual operating point to the maximum efficiency point after passing through the constant current circle SI, the d-axis target current Id * is set. Will be changed in the positive direction. As a result, the field current decreases from time tB to time tC. Therefore, even if the actual operating point reaches the maximum efficiency point at time tC, the torque generated by the rotary electric machine 10 does not reach the maximum torque Tmax, and the timing at which the generated torque reaches the maximum torque Tmax is until the time tD. Will be delayed. That is, the responsiveness of the generated torque decreases, and the time from the input of the start command to the completion of the start of the engine 20 becomes long.

  Subsequently, FIG. 8 also shows the engine starting process according to the present embodiment and the related technique 2. In FIG. 8, the processing part according to the present embodiment is the same as that shown in FIG. The related technique 2 will be described below.

  In Related Art 2, the d-axis target current Id * is set to the d-axis positive side maximum value Idmax by inputting the start command of the engine 20 to the control device 40, and the q-axis target current Iq * remains 0. To be done. Further, when the start command is input to the control device 40, the field target current If * is set and the field current starts to increase.

  After that, from time tA to tB, the actual operating point changes from the initial operating point to the intermediate operating point on the constant current circle SI. Here, the intermediate operating point is an operating point at which the d-axis target current Id * becomes the d-axis negative side maximum value −Idmax and the q-axis target current Iq * becomes zero. The initial operating point is the same as the initial operating point according to this embodiment.

  At time tB, the field current Ifr reaches the field target current If. At time tB, the actual operating point begins to change from the intermediate operating point toward the maximum efficiency point. However, as in Related Art 1, the d-axis target current Id * is set to the d-axis negative side maximum value −Idmax. Therefore, in order to change the actual operating point to the maximum efficiency point after passing through the constant current circle SI. , D-axis target current Id * is changed in the positive direction. As a result, the field current decreases from time tB to time tC. Therefore, the timing at which the torque generated by the rotary electric machine 10 reaches the maximum torque Tmax is delayed, and the responsiveness of the torque generated is reduced.

  The effects of this embodiment described above will be described.

  After the field current was started to flow, the actual operating point was changed from the initial operating point to the maximum efficiency point, provided that the d-axis target current Id * changed only in the negative direction. Therefore, it is possible to prevent a process in which the changing direction of the d-axis current becomes a positive direction in the process of changing the actual operating point from the initial operating point to the maximum efficiency point. As a result, it is possible to prevent the field current from decreasing and improve the responsiveness of the torque generated by the rotating electric machine 10. Therefore, the start of the engine 20 can be completed quickly.

  Note that, as shown in FIG. 9, the maximum efficiency point can be set on the positive side of the d-axis. In this case, in Related Techniques 1 and 2, the amount of change in the d-axis target current Id * in the positive direction becomes large, and the degree of decrease in the field current becomes large. On the other hand, according to the present embodiment, such inconvenience can be prevented.

  -The d-axis target current Id * that defines the initial operating point was set to a positive value. That is, before changing the actual operating point toward the maximum efficiency point, a positive d-axis current was passed. Therefore, the amount of change of the d-axis current in the negative direction can be increased, and the field current can be quickly raised to the field target current If *. As a result, the torque generated by the rotary electric machine 10 can be raised more quickly, and the start of the engine 20 can be completed more quickly.

  -The actual operating point was changed through the constant current circle SI from the initial operating point to the maximum efficiency point. Therefore, the q-axis current can be rapidly increased in the positive direction, and the torque generated by the rotating electrical machine 10 can be quickly raised to the maximum torque Tmax.

(Second embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, the method of predicting the increase amount ΔF of the field current is changed.

  FIG. 10 shows the procedure of the engine starting process according to the present embodiment. This processing is repeatedly executed by the control device 40, for example, in a predetermined processing cycle. Note that in FIG. 10, the same processes as those in FIG. 3 described above are denoted by the same reference numerals for convenience.

  In this series of processes, after the process of step S14 is completed, the process proceeds to step S22. In step S22, the increase amount ΔF of the field current is predicted. In the present embodiment, the increase amount ΔF is mapped in association with the field current Ifr and the change amount ΔD of the d-axis current. This map is stored in the memory as the increase amount storage unit of the control device 40.

  In step S22, first, the change amount ΔD of the d-axis current is calculated using the above equation (eq3). Then, the increase amount ΔF is calculated from the map based on the calculated change amount ΔD and the field current Ifr in the current processing cycle. Then, it progresses to step S18.

  Also according to the present embodiment described above, the same effect as that of the first embodiment can be obtained.

(Other embodiments)
The above embodiments may be modified and implemented as follows.

  In each of the above embodiments, the actual operating point is changed from the initial operating point to the highest efficiency point on the constant current circle SI, but the present invention is not limited to this. For example, as shown in FIG. 11, the actual operating point may be changed through a region inside the constant current circle SI.

  In each of the above embodiments, the initial operating point is set in the area on the positive side of the d-axis, but it is not limited to this. For example, the d-axis target current Id * defining the initial operating point is lower than the d-axis positive side maximum value Idmax by the d-axis negative value, provided that the initial operating point exists in the positive direction of the d-axis with respect to the d-axis efficiency current Ide. The initial operating point may be set so that it exists in the area of the direction. FIG. 12 shows an example in which the initial operating point is set to the origin 0 of the dq coordinate system.

  In each of the above embodiments, the maximum efficiency point is set on the constant current circle SI, but the present invention is not limited to this, and the maximum efficiency point may be set in a region inside the constant current circle SI.

  In each of the above-mentioned embodiments, the d-axis target current Id * is started to change in the positive direction at the same time when the field current is started to flow. For example, the d-axis target current Id * may be changed in the positive direction before the flow of the field current or after the flow of the field current.

  In each of the above embodiments, if it is determined that the field current reaches the field target current If * assuming that the d-axis target current Id * is increased in the negative direction, the d-axis current is increased in the negative direction. I did, but it is not limited to this. After the field current has started to flow, the d-axis target current Id * may be increased in the negative direction before the timing when it is determined that the field current reaches the field target current If *.

  The rotary electric machine is not limited to one including one armature winding group, and may be a multiple winding type synchronous machine including two or more armature winding groups. Further, the application of the rotating electric machine is not limited to starting the engine, but may be other applications such as driving an in-vehicle accessory.

  10 ... Rotating electric machine, 11 ... Field winding, 12 ... Rotor, 13 ... Stator, 13U, 13V, 13W ... U, V, W phase winding, 40 ... Control device.

Claims (8)

It is applied to a rotating electric machine (10) including a rotor (12) having a field winding (11) and a stator (13) having armature windings (13U to 13W),
In the rotating coordinate system of the rotating electric machine, a current flowing through the armature winding along the direction of a field magnetic flux generated by flowing a field current through the field winding is defined as a d-axis current. The current flowing in the armature winding in the direction orthogonal to is defined as the q-axis current,
The sign of the d-axis current flowing in the direction of canceling the field magnetic flux is defined as negative, and the sign of the q-axis current when the rotating electric machine generates torque is defined as positive.
A field controller (40) for controlling the field current,
In the middle of the period from when the field current is started to flow by the field controller to when the field current increases and reaches the field target current, the changing direction of the d-axis current is set only in the negative direction. An armature control unit (40) for controlling a current flowing through the armature winding in order to change the d-axis current and to flow a positive q-axis current as a condition ,
The armature controller controls the current flowing through the armature winding in order to flow a positive d-axis current before changing the d-axis current,
In the rotating coordinate system, the operating point at which the generated torque of the rotating electric machine per unit amplitude of the current vector flowing through the rotating electric machine is maximum is defined as the maximum efficiency point,
The armature control unit starts to change the d-axis current and starts to flow a positive q-axis current, and then changes the actual operating point up to the maximum efficiency point. For controlling a rotating electric machine that controls the motor. The maximum efficiency point exists on a constant current circle drawn by the current vector in the rotating coordinate system,
In the rotating coordinate system, an operating point existing on the constant current circle and having a positive d-axis current and zero q-axis current is defined as an initial operating point,
The armature control unit, said from the initial operating point to the maximum efficiency point in order to change the actual the operating point through a constant current circle, claim 1 for controlling the current flowing in the armature winding The control device for the rotating electric machine according to item 1. A current calculation unit (40) for calculating a d-axis efficiency current that is a d-axis current that defines the maximum efficiency point,
The armature control unit changes the current flowing through the armature winding in order to change the actual operating point to the maximum efficiency point defined by the d-axis efficiency current calculated by the current calculation unit. The control device for a rotating electric machine according to claim 1 or 2, which is controlled. A current information storage unit (40) for storing information on the d-axis efficiency current associated with the field current,
The control device for a rotating electric machine according to claim 3 , wherein the current calculation unit calculates the d-axis efficiency current based on the field target current and information stored in the current information storage unit. An arrival determination unit (40) for determining whether or not the field current reaches the field target current, assuming that the d-axis current is changed in the negative direction after the field current is started to flow. Prepare,
When the arrival determination unit determines that the armature control unit reaches, the armature control unit changes the d-axis current and supplies a positive q-axis current on condition that the changing direction of the d-axis current is only the negative direction. Therefore, the control device for a rotary electric machine according to any one of claims 1 to 4 for controlling the current flowing in the armature winding. A prediction unit (40) for predicting an increase amount of the field current when it is assumed that the d-axis current is changed in the negative direction after the field current is started to flow;
When the arrival determination unit determines that the increase amount predicted by the prediction unit is equal to or greater than the difference between the current field current and the field target current, the field current is the field target current. The control device for the rotating electric machine according to claim 5 , wherein the control device determines that An increase amount memory that stores the increase amount information of the field current on the assumption that the d-axis current is changed in the negative direction in association with the change amount of the d-axis current in the negative direction and the field current. Part (40),
The control device for a rotary electric machine according to claim 6 , wherein the prediction unit predicts the increase amount by using information stored in the increase amount storage unit. It is applied to a system including the rotating electric machine and an engine (20),
The output shaft (20a) of the engine and the rotor are connected so that power can be transmitted,
The armature control unit, when the start request of the engine is input, to impart an initial rotation to the output shaft, any one of claims 1 to 7 for controlling the current flowing in the armature winding The control device for the rotating electric machine according to item 1.

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