Control device of rotating electrical machine and control program

Abstract

To provide a control device for a rotating electrical machine and a control program capable of suppressing a deviation of a frequency of an actual flowing field current from a target frequency of the field current.SOLUTION: A control device 30 for a rotating electrical machine having a stator including a stator winding and a rotor including a field winding calculates an excitation current to be passed through the stator winding to excite a field current in the field winding and performs switching control of an inverter to pass a composite current in which the excitation current is superimposed on the fundamental current to be passed to the stator winding, to the stator winding. The control device 30 calculates the excitation current including a component of a lower side frequency obtained by subtracting an electrical angle frequency of the rotor from the target frequency of the field current and a component of an upper side frequency obtained by adding the electrical angle frequency to the target frequency.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present disclosure relates to a control device and a control program for a rotating electric machine. [Background technology]

[0002] A wound field type rotating electric machine having a stator including a stator winding and a rotor including a field winding is known. In the rotating electric machine described in Patent Document 1, a high-frequency excitation current is superimposed on a fundamental wave current of the stator to induce a current in the rotor field winding. The induced current is rectified into a unidirectional current by a rotor rectifier circuit and used as a field current. The field winding is divided into a first part and a second part, and in the rotor rectifier circuit, one end of a capacitor is connected to a connection point between the first part and the second part, and the other end is connected to one end of a diode. In the rotor rectifier circuit, a series resonant circuit is formed by the first part of the field winding and the capacitor, and a parallel resonant circuit is formed by the second part of the field winding and the capacitor. The resonant frequency of the series resonant circuit is called a series resonant frequency, and the resonant frequency of the parallel resonant circuit is called a parallel resonant frequency. By controlling the frequency of the high frequency excitation current to be between the series resonant frequency and the parallel resonant frequency, or to a value close to the series resonant frequency or the parallel resonant frequency, the impedance during excitation of the rotor field winding is reduced, and the torque ripple caused by the high frequency excitation current is reduced. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2018-102111 A Summary of the Invention [Problem to be solved by the invention]

[0004] The frequency of the field current flowing through the rotor field winding varies depending on the rotation speed of the rotor. For this reason, as in Patent Document 1, if the frequency of the high-frequency excitation current is set to be composed of a single frequency component with respect to the target frequency, which is the target value of the field current flowing through the field winding, the frequency of the field current that actually flows may deviate from the target frequency. For example, even if the target frequency of the field current is set to be close to the first resonant frequency or the second resonant frequency in order to reduce torque ripple, the frequency of the field current that actually flows may deviate from the vicinity of the first resonant frequency or the second resonant frequency, and there is a concern that the torque ripple cannot be reduced.

[0005] An object of the present disclosure is to provide a control device and a control program for a rotating electric machine that can suppress deviation of the frequency of an actually flowing field current from a target frequency of the field current. [Means for solving the problem]

[0006] The present disclosure relates to a control device for a rotating electric machine that is applied to a system including a rotating electric machine having a stator including a stator winding and a rotor including a field winding, and an inverter electrically connected to the stator winding, and includes an excitation current calculation unit that calculates an excitation current to be passed through the stator winding in order to induce a field current in the field winding, and a switch control unit that performs switching control of the inverter so as to pass through the stator winding a composite current in which an excitation current having a frequency higher than that of a fundamental wave current to be passed through the stator winding is superimposed on the fundamental wave current to be passed through the stator winding, and the excitation current calculation unit calculates the excitation current that includes a lower frequency component obtained by subtracting the electrical angular frequency of the rotor from a target frequency of the field current, and an upper frequency component obtained by adding the electrical angular frequency to the target frequency.

[0007] The frequency of the field winding can be set to the target frequency by including in the excitation current two frequency components obtained by subtracting or adding the electrical angular frequency of the rotor to or from the target frequency of the field current.

[0008] In consideration of this point, the excitation current calculation unit of the present disclosure calculates an excitation current including a lower frequency component obtained by subtracting an electrical angle frequency from a target frequency of the field current and an upper frequency component obtained by adding an electrical angle frequency to the target frequency, thereby making it possible to suppress deviation of the frequency of the actual field current from the target frequency of the field current. [Brief description of the drawings]

[0009] [Figure 1] 1 is an overall configuration diagram of a control system for a rotating electrical machine according to an embodiment; [Diagram 2] FIG. 2 is a diagram showing an inverter and its peripheral configuration. [Diagram 3] FIG. [Figure 4] FIG. 4 is a diagram showing an electric circuit provided in the rotor. [Diagram 5] FIG. 4 is a block diagram of a torque control process of the control device. [Figure 6] 1 is a diagram showing a fundamental wave current and a high-frequency excitation current (harmonic current). [Figure 7] FIG. 4 is a diagram showing the relationship between a target frequency and upper and lower frequency components. [Figure 8] 4 is a diagram showing the relationship between the frequency of a current flowing through a winding and the torque of a rotating electric machine. [Figure 9] 5 is a diagram showing the relationship between a change in resonance frequency and the torque of a rotating electric machine. [Figure 10] 4 is a flowchart showing a control process for a rotating electric machine. [Figure 11] FIG. 11 is a diagram showing a fundamental wave current and a high-frequency excitation current according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of a control device for a rotating electric machine according to the present disclosure will be described with reference to the drawings. A rotating electric machine 40 and a control device 30 shown in FIG. 1 constitute a control system for the rotating electric machine, and the control system is mounted on a vehicle. The rotating electric machine is a power source for running the vehicle. As shown in FIG. 1, the control system includes a DC power source 10, an inverter 20, a control device 30, and the rotating electric machine 40. The rotating electric machine 40 is a self-excited field winding type synchronous machine. For example, a mechanically and electrically integrated drive device may be configured by including the rotating electric machine 40, the inverter 20, and the control device 30, or the rotating electric machine 40, the inverter 20, and the control device 30 may each be configured by a respective component.

[0011] The rotating electric machine 40 includes a housing 41, and a stator 50 and a rotor 60 housed in the housing 41. The rotating electric machine 40 of this embodiment is an inner rotor type rotating electric machine in which the rotor 60 is disposed radially inside the stator 50.

[0012] The stator 50 includes a stator core 51 and a stator winding 52. The stator winding 52 is made of, for example, a copper wire, and includes U-, V-, and W-phase windings 52U, 52V, and 52W that are arranged offset from each other by 120° in electrical angle.

[0013] The rotor 60 includes a rotor core 61 and a field winding 70. The field winding 70 is made of, for example, an aluminum wire, a copper wire, or a CNT (carbon nanotube).

[0014] The rotating shaft 32 is inserted through a central hole of the rotor core 61. The rotating shaft 32 is rotatably supported by the housing 41 via a bearing .

[0015] As shown in FIG. 2, the inverter 20 includes a series connection of U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp and U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn. First ends of the U-, V-, and W-phase windings 52U, 52V, and 52W are connected to the connection points of the U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp and the U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn. Second ends of the U-, V-, and W-phase windings 52U, 52V, and 52W are connected at the neutral point. That is, in this embodiment, the U-, V-, and W-phase windings 52U, 52V, and 52W are star-connected. In this embodiment, each of the switches SUp to SWn is an IGBT. A freewheel diode is connected in inverse parallel to each of the switches SUp to SWn.

[0016] The collectors of the U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp are connected to a positive terminal of a DC power supply 10. The emitters of the U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn are connected to a negative terminal of the DC power supply 10. A smoothing capacitor 11 is connected in parallel to the DC power supply 10.

[0017] Next, the stator 50 and the rotor 60 will be described with reference to FIG.

[0018] The stator 50 and the rotor 60 are both arranged coaxially (specifically, on the central axis O of rotation) with the rotating shaft 32. In the following description, the direction in which the rotating shaft 32 extends is referred to as the axial direction, the direction extending radially from the center of the rotating shaft 32 is referred to as the radial direction, and the direction extending circumferentially around the rotating shaft 32 is referred to as the circumferential direction.

[0019] The stator 50 is made of laminated steel plates made of soft magnetic material, and has an annular back yoke 51a and a plurality of teeth 51b protruding radially inward from the back yoke 51a. A plurality of slots 54 are formed between adjacent teeth 51b in the circumferential direction. The phase windings of each phase are accommodated in each slot 54 in a predetermined order to form the stator winding 52. For example, the stator 50 may have a segment coil structure using a plurality of conductor segments. However, the structure of the stator winding 52 is arbitrary.

[0020] The rotor 60 is made of a soft magnetic material, for example, laminated steel plates. The rotor 60 has a cylindrical rotor core 61 and a plurality of main poles 62 protruding radially outward from the rotor core 61. In this embodiment, eight main poles 62 are provided at equal intervals in the circumferential direction.

[0021] The field winding 70 includes a first winding portion 71a and a second winding portion 71b. In each main pole portion 62, the first winding portion 71a is wound radially outward, and the second winding portion 71b is wound radially inward from the first winding portion 71a. In each main pole portion 62, the winding directions of the first winding portion 71a and the second winding portion 71b are the same. In addition, among the main pole portions 62 adjacent in the circumferential direction, the winding directions of the winding portions 71a and 71b wound around one of the main pole portions 62 are opposite to the winding directions of the winding portions 71a and 71b wound around the other of the main pole portions 62 adjacent in the circumferential direction. Therefore, the magnetization directions of the main pole portions 62 adjacent in the circumferential direction are opposite to each other.

[0022] FIG. 4 shows the electric circuit on the rotor 60 side including each winding part 71a, 71b wound around the common main pole part 62. A diode 80 as a rectifying element and a capacitor 90 are provided in the rotor 60. The diode 80 is electrically connected in parallel to the series connection body of the first winding part 71a and the second winding part 71b. Specifically, the first end of the first winding part 71a is connected to the cathode of the diode 80, and the first end of the second winding part 71b is connected to the second end of the first winding part 71a. The anode of the diode 80 is connected to the second end of the second winding part 71b. A capacitor 90 is electrically connected in parallel to the second winding part 71b. In FIG. 4, L1 represents the inductance of the first winding part 71a, L2 represents the inductance of the second winding part 71b, and C represents the capacitance of the capacitor 90.

[0023] In this embodiment, a series resonance circuit composed of the first winding part 71a, the capacitor 90, and the diode 80 is configured, and a parallel resonance circuit composed of the second winding part 71b and the capacitor 90 is configured. The series resonance circuit shown in FIG. 4 corresponds to a first circuit composed of the first winding part 71a and the capacitor 90, and the first resonance frequency f1 is the resonance frequency of the first circuit (series resonance circuit). The parallel resonance circuit shown in FIG. 4 corresponds to a second circuit composed of the second winding part 71b and the capacitor 90, and the second resonance frequency f2 is the resonance frequency of the second circuit (parallel resonance circuit). Each resonance frequency f1, f2 is represented by the following formulas (1), (2). In this embodiment, when the number of turns of the first winding part 71a is made smaller than the number of turns of the second winding part 71b, "L1 < L2" is obtained, and the first resonance frequency f1 becomes a frequency higher than the second resonance frequency f2.

[0024]

Number

[0025]

Number

[0026] Returning to the explanation of Fig. 2, the control system includes a current sensor 21, an angle sensor 22, and a voltage sensor 23. The current sensor 21 detects at least two phases of current among the phase currents flowing through the rotating electric machine 40. The angle sensor 22 detects the rotation angle (electrical angle) of the rotor 60. The voltage sensor 23 detects the voltage of the DC power supply 10. The detection values ​​of the sensors 21 to 23 are input to the control device 30.

[0027] The control device 30 is an electronic control unit mainly composed of a microcomputer 31. The microcomputer 31 includes a CPU (Central Processing Unit). The functions provided by the microcomputer 31 can be provided by software recorded in a physical memory device and a computer that executes the software, by software alone, by hardware alone, or by a combination of these. For example, when the microcomputer 31 is provided by an electronic circuit that is hardware, it can be provided by a digital circuit including a large number of logic circuits, or by an analog circuit. For example, the microcomputer 31 executes a program stored in a non-transitory tangible storage medium as a storage unit that the microcomputer 31 includes. A set of instructions that constitute the program is executed, thereby executing a method corresponding to the program. The storage unit is, for example, a non-volatile memory. The program stored in the storage unit can be updated via a communication network such as the Internet, for example, OTA (Over The Air), etc.

[0028] The control device 30 generates drive signals that turn on and off each of the switches SUp to SWn that configure the inverter 20. In particular, the control device 30 generates drive signals that turn on and off each of the arm switches SUp to SWn in order to convert the DC power output from the DC power source 10 into AC power and supply it to the U-, V-, and W-phase windings 52U, 52V, and 52W, and supplies the generated drive signals to the gates of each of the arm switches SUp to SWn.

[0029] The control device 30 turns on and off the switches SUp to SWn so that a composite current of a fundamental current and a high-frequency excitation current having a frequency higher than that of the fundamental current flows through each of the phase windings 52U, 52V, 52W. The fundamental current is a current that mainly serves to generate torque in the rotating electric machine 40. The high-frequency excitation current is a current that mainly serves to excite the field winding 70 and induce a field current in the field winding 70. The phase currents flowing through the phase windings 52U, 52V, 52W are shifted by 120° in electrical angle.

[0030] The torque control of the rotating electrical machine 40 executed by the control device 30 will be described with reference to FIG.

[0031] The command voltage calculation unit 108 calculates U-, V-, and W-phase voltage command values ​​VUref, VVref, and VWref in a three-phase fixed coordinate system based on the command torque Tref, the detection value of the current sensor 21, and the electrical angle θe detected by the angle sensor 22. The U-, V-, and W-phase voltage command values ​​VUref, VVref, and VWref have waveforms with phases shifted by 120 degrees in electrical angle. In this embodiment, the command voltage calculation unit 108 corresponds to an "excitation current calculation unit."

[0032] The signal generating unit 109 generates drive signals for the upper and lower arm switches SUp-SWn in the U, V and W phases based on the U, V and W phase voltage command values ​​VUref, VVref and VWref for passing the above-mentioned composite current through the stator winding 52. The generated drive signals are input to the gates of the respective switches. This executes switching control of the inverter 20. In this embodiment, the signal generating unit 109 corresponds to a "switch control unit."

[0033] As a result of switching control of inverter 20, a composite current in which a high-frequency excitation current (see solid line in FIG. 6(b)) is superimposed on a fundamental current (see FIG. 6(a)) flows through each phase winding 52U, 52V, 52W. The high-frequency excitation current flowing through stator winding 52 causes a field current to flow through field winding 70. FIG. 6(a) shows the transition of the fundamental current over one electrical angle period. The dashed dotted line in FIG. 6(b) shows the envelope of the high-frequency excitation current. The envelope of the high-frequency excitation current shown in FIG. 6(b) has the same period as the fundamental current. The value on the vertical axis in FIG. 6 indicates the relative relationship between the magnitudes of the waveforms shown in FIGS. 6(a) and 6(b).

[0034] In addition, the high-frequency excitation current is not limited to a harmonic excitation current whose fluctuation frequency is N times (N is an integer equal to or greater than 2) the frequency of the fundamental current, and may be a current whose fluctuation frequency is different from N times the frequency of the fundamental current as long as the fluctuation frequency is higher than the frequency of the fundamental current.

[0035] Taking the U-phase as an example, as a result of switching control of the inverter 20, the fundamental current IUb flowing through the U-phase winding 52U is expressed by the following formula (3), and the high-frequency excitation current IUh is expressed by the following formula (4). In the following formulas (3) and (4), IUamp is the effective value of the amplitude of the fundamental current IUb, ωe is the electrical angular velocity of the rotor 60, Rh is the harmonic rate (%), and fi is the target frequency that is the target value of the fluctuation frequency of the field current. For simplicity, in the following formulas (3) and (4), the phase θs of the fundamental current IUb, the phase θh of the high-frequency excitation current IUh, and the phase θR of the high-frequency excitation current IUh relative to the fundamental current IUb are all set to zero (θs=0, θR=0, θh=0).

[0036]

number

[0037]

number

[0038]

number

[0039] As described above, the control device 30 causes the high-frequency excitation current to include both the lower frequency feL (= fi - fr) and the upper frequency feH (= fi + fr). The high-frequency excitation current is not composed of only a single frequency component, but is composed of two components, namely, the component of the lower frequency feL and the component of the upper frequency feH. Therefore, it is possible to suppress the frequency of the actually flowing field current from deviating from the target frequency fi due to the influence of the rotational speed of the rotor 60. Therefore, it is possible to suppress the deviation of the frequency of the actually flowing field current from the target frequency fi of the field current.

[0040] The ability to suppress the frequency of the field current flowing through the field winding 70 from deviating from the target frequency fi can contribute to improving the performance of the rotating electrical machine 40. For example, if the target frequency fi of the field current is set to a frequency near the first resonance frequency f1, the magnetizing property can be enhanced to reduce the amplitude of the high-frequency excitation current, and the torque ripple of the rotating electrical machine 40 can be reduced.

[0041] Subsequently, with reference to FIGS. 8 and 9, the method for setting the target frequency fi will be described in detail.

[0042] FIG. 8 is a characteristic diagram showing the relationship between the target frequency fi of the field current and the torque Tq of the rotating electrical machine 40. In FIG. 8, the horizontal axis represents the target frequency fi, and the vertical axis represents the torque Tq. In the field winding 70 shown in FIG. 4, the first resonance frequency f1 is higher than the second resonance frequency f2. Let the minimum value of the range of the target frequency fi that can be realized in the control system be the minimum frequency fmin, and the maximum value of the above range be the maximum frequency fmax. In the above range, the second resonance frequency f2, which is the parallel resonance frequency, is the frequency at which the torque Tq becomes the minimum value Trmin, and the first resonance frequency f1, which is the series resonance frequency, is the frequency at which the torque Tq becomes the maximum value Trmax. The torque Tq of the rotating electrical machine 40 decreases as the target frequency fi increases in the range of fmin ≦ fi < f2, becomes the minimum value at fi = f2, increases as the target frequency fi increases in the range of f1 > fi > f2, becomes the maximum value at fi = f1, and decreases as the target frequency fi increases in the range of fmax ≧ fi > f1.

[0043] As shown in FIG. 8, compared with the range where fmin ≦ fi < f1, in the range where fmax ≧ fi ≧ f1, the change amount of the torque Tq with respect to the change amount of the target frequency fi is small. In the range where fi > f1, the higher the target frequency fi, the smaller the torque Tq becomes. However, the higher the target frequency fi, the more the torque Tq approaches a predetermined torque.

[0044] The control device 30 sets the target frequency fi so as to have a value closer to the first resonance frequency f1 than the second resonance frequency f2. In this case, the target frequency fi is higher than the median value "(f1 + f2) / 2" which is the median of the first resonance frequency f1 and the second resonance frequency f2. As shown by A in FIG. 8, the control device 30 can set the target frequency fi to a value higher than "(f1 + f2) / 2". In this case, the rotating electrical machine 40 can be operated under the condition that the torque Tq becomes relatively large.

[0045] The control device 30 preferably sets the target frequency fi of the field current to a value higher than the first resonance frequency f1. Such a range of the target frequency fi is the range shown by B in FIG. 8 (the range where fi > f1). As shown in FIG. 8, the change amount of the torque Tq with respect to the change amount of the target frequency fi within the range B is smaller than the change amount of the torque Tq with respect to the change amount of the target frequency fi outside the range B. Also, the value of the torque Tq within the range B is a relatively large value close to the maximum value Trmax of the torque Tq at fi = f1 although it does not reach the maximum value Trmax. That is, when the target frequency fi of the field current is set to a value higher than the first resonance frequency f1, the rotating electrical machine 40 can be operated under the condition that the torque Tq is relatively large and the change amount of the torque Tq is small.

[0046] The first resonant frequency f1 and the second resonant frequency f2 may become higher or lower than their initial values ​​(for example, values ​​when the control system is new) due to deterioration of the field winding 70 caused by current flowing through the field winding 70, temperature characteristics of the field winding 70, and the like. In FIG. 9, XN, XL, and XH are all curves showing the relationship between the torque Tq and the target frequency fi, similar to FIG. 8. The first curve XN shows the characteristics when there is no deviation in the first resonant frequency f1 (for example, when the control system is new). The second curve XL shows the characteristics when the first resonant frequency f1 deviates to the lower side. The third curve XH shows the characteristics when the first resonant frequency f1 deviates to the higher side.

[0047] The first resonance frequency f1 shown in FIG. 9 is the initial frequency and is a reference frequency. FIG. 9 shows a case where the target frequency fi of the field current is set to a value fa lower than the initial first resonance frequency f1, and a case where it is set to a value fb higher than the initial first resonance frequency f1. Tqa and Tqb indicate a torque difference that may occur when the first resonance frequency f1 shifts from the low side to the high side. When the target frequency fi of the field current is set to a value fa lower than the first resonance frequency f1, the value of the torque Tq on the second curve XL is close to the maximum value Trmax of the torque Tq, while the value of the torque Tq on the third curve XH is close to the minimum value Trmin of the torque Tq. As a result, the torque difference Tqa becomes a large value.

[0048] On the other hand, when the target frequency fi of the field current is set to a value fb higher than the first resonance frequency f1, the frequency fb is higher than the first resonance frequency of either the second or third curve XL, XH. Therefore, even if a change occurs in the difference between the first resonance frequency and the frequency fb, the change amount of the torque Tq is relatively small. The value of the torque Tq in the second curve XL and the value of the torque Tq in the third curve XH both become values close to the maximum value Trmax of the torque Tq. As a result, the torque difference Tqb becomes a smaller value compared to the torque difference Tqa. From the above, it is preferable for the control device 30 to set the target frequency fi of the field current to a value higher than the first resonance frequency f1. In this case, even when the first resonance frequency f1 or the second resonance frequency f2 changes due to deterioration of the field winding 70 or the like, the change amount of the torque Tq obtained with respect to the target frequency fi can be made small.

[0049] The control device 30 may set the target frequency fi such that the value obtained by subtracting the electrical angular frequency frmax when the rotational speed of the rotor 60 is the maximum rotational speed from the target frequency fi of the field current is higher than the first resonance frequency f1. Such a range of the target frequency fi is the range indicated by C in FIG. 8 (the range of fi > f1 + frmax). "fi - frmax" corresponds to the lower frequency feL when the rotational speed of the rotor 60 is the maximum rotational speed. By setting the target frequency fi so as to satisfy "f1 < fi - frmax", the rotating electrical machine 40 can be operated under the conditions that the torque Tq is relatively large and the change amount of the torque Tq is small regardless of the rotational speed of the rotor 60.

[0050] The control device 30 may set the target frequency fi of the field winding 70 to 1 / 10 or less of the carrier frequency fc in the inverter 20 (that is, the frequency at which each switch SUp to SWn constituting the inverter 20 is switched) (fi ≤ fc / 10). Such a range of the target frequency fi is shown as a range indicated by D in FIG. 8 (a range where fi ≤ fc / 10) as an example. When the target frequency fi is set in this way, a synthesized current in which a high-frequency excitation current of 10 electrical angle cycles or more is superimposed during one electrical angle cycle of the fundamental wave current can flow through the stator winding 52. As a result, distortion of the fundamental wave current can be suppressed.

[0051] FIG. 10 shows a flowchart of a process for controlling the rotating electrical machine 40 executed by the control device 30. The process shown in FIG. 10 is realized, for example, by a CPU constituting the control device 30 executing a program installed in a ROM. This process is repeatedly executed, for example, at a predetermined control cycle.

[0052] In step S101, the command voltage calculation unit 108 sets the target frequency fi so as to have a value closer to the first resonance frequency f1 than the second resonance frequency f2.

[0053] Note that it is preferably configured to set the target frequency fi such that fi > f1, and further, it may be configured to set the target frequency fi that satisfies f1 < fi - frmax. Also, it may be configured to set the target frequency fi that satisfies fi ≤ fc / 10.

[0054] In step S101, the command voltage calculation unit 108 calculates U, V, W phase voltage command values VUref, VVref, VWref including a component of the lower frequency feL and a component of the upper frequency feH.

[0055] In step S102, the signal generation unit 109 generates drive signals for the upper and lower arm switches SUp to SWn in the U, V, W phases based on the calculated U, V, W phase voltage command values VUref, VVref, VWref.

[0056] As described above, according to the control program for the rotating electric machine 40 according to the present embodiment and the control method executed by the control program, an excitation current calculation step is executed to calculate a high-frequency excitation current to be passed through the stator winding in order to induce a field current in the field winding 70, as shown in step S101. In the excitation current calculation step, the component of the lower frequency feL and the component of the upper frequency feH are included in the high-frequency excitation current. Also, as shown in step S102, a switch control step is executed to control the switching of the inverter 20 so that a composite current in which the high-frequency excitation current is superimposed on the fundamental current to be passed through the stator winding 52 is passed through the stator winding 52. This makes it possible to suppress deviation of the frequency of the field current that actually flows from the target frequency fi of the field current. As a result, this can contribute to improving the performance of the rotating electric machine 40.

[0057] <Other embodiments> The above embodiment may be modified as follows.

[0058] The high frequency excitation current applied to the stator winding is not limited to the sine wave shown in FIG. 6(b), but may be a square wave shown in FIG. 11(b).

[0059] In the rotor 60, the second winding portion 71b may be disposed closer to the stator 50 in the radial direction than the first winding portion 71a.

[0060] The rotating electric machine is not limited to an inner rotor type rotating electric machine, but may be an outer rotor type rotating electric machine. In this case, the main pole portion protrudes radially inward from the rotor core.

[0061] The rotating electric machine is not limited to a star-connected rotating electric machine, but may be a delta-connected rotating electric machine.

[0062] The stator core may not be provided with teeth.

[0063] The rotating electric machine is not limited to a rotating electric machine used as an in-vehicle main engine, but may be, for example, a rotating electric machine used as an ISG (Integrated Starter Generator) that serves as both a motor and a generator.

[0064] The moving body on which the control system is mounted is not limited to a vehicle, but may be, for example, an aircraft or a ship. Furthermore, the control system is not limited to a system mounted on a moving body, but may be a stationary system.

[0065] The control device and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control device and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control device and the method described in the present disclosure may be realized by one or more special-purpose computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer.

[0066] The technical ideas extracted from the above-described embodiments will be described below. [Configuration 1] a rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A control device (30) for a rotating electric machine applied to a system including: an excitation current calculation unit that calculates an excitation current to be passed through the stator winding in order to induce a field current in the field winding; a switch control unit that performs switching control of the inverter so as to cause a composite current, which is a fundamental current to be passed through the stator winding and the excitation current having a frequency higher than that of the fundamental current, to flow through the stator winding; Equipped with The excitation current calculation unit A control device for a rotating electric machine that calculates the excitation current including a lower frequency component (fi-fr) obtained by subtracting the electrical angular frequency (fr) of the rotor from a target frequency (fi) of the field current, and an upper frequency component (fi+fr) obtained by adding the electrical angular frequency to the target frequency. [Configuration 2] The rotor has a rotor core (61) and main pole portions (62) that are provided at predetermined intervals in the circumferential direction and protrude radially from the rotor core, the field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode (80) electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor (90) electrically connected in parallel with the second winding portion; having The control device for a rotating electric machine according to configuration 1, wherein the excitation current calculation unit sets the target frequency to a value closer to a first resonant frequency (f1), which is a resonant frequency in a first circuit formed by the first winding unit and the capacitor, than to a second resonant frequency (f2), which is a resonant frequency in a second circuit formed by the second winding unit and the capacitor. [Configuration 3] the first resonant frequency is higher than the second resonant frequency; 3. The control device for a rotating electric machine according to configuration 2, wherein the excitation current calculation unit sets a target frequency of the field current to a value higher than the first resonant frequency. [Configuration 4] The control device for a rotating electric machine according to configuration 3, wherein the excitation current calculation unit sets the target frequency such that a value obtained by subtracting the electrical angular frequency when the rotation speed of the rotor becomes a maximum rotation speed from the target frequency of the field current is a value higher than the first resonant frequency. [Configuration 5] 5. The control device for a rotating electric machine according to any one of configurations 2 to 4, wherein the number of turns of the first winding portion is smaller than the number of turns of the second winding portion. [Configuration 6] 6. The control device for a rotating electric machine according to any one of configurations 1 to 5, wherein the excitation current calculation unit sets the target frequency to 1 / 10 or less of a carrier frequency in the inverter. [Explanation of symbols]

[0067] 30... inverter, 30... control device, 40... rotating electric machine, 50... stator, 52... stator winding, 60... rotor, 70... field winding.

Claims

1. A rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A control device (30) for a rotating electric machine applied to a system including: an excitation current calculation unit that calculates an excitation current to be passed through the stator winding in order to induce a field current in the field winding; a switch control unit that performs switching control of the inverter so as to cause a composite current, which is a fundamental current to be passed through the stator winding and the excitation current having a frequency higher than that of the fundamental current, to flow through the stator winding; Equipped with The excitation current calculation unit A control device for a rotating electric machine that calculates the excitation current including a lower frequency component (fi-fr) obtained by subtracting the electrical angular frequency (fr) of the rotor from a target frequency (fi) of the field current, and an upper frequency component (fi+fr) obtained by adding the electrical angular frequency to the target frequency.

2. The rotor has a rotor core (61) and main pole portions (62) provided at predetermined intervals in the circumferential direction and protruding in the radial direction from the rotor core, The field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode (80) electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor (90) electrically connected in parallel with the second winding portion; having 2. The control device for a rotating electric machine according to claim 1, wherein the excitation current calculation unit sets the target frequency to a value closer to a first resonant frequency (f1), which is a resonant frequency in a first circuit formed by the first winding portion and the capacitor, than to a second resonant frequency (f2), which is a resonant frequency in a second circuit formed by the second winding portion and the capacitor.

3. the first resonant frequency is higher than the second resonant frequency; The control device for a rotating electric machine according to claim 2 , wherein the excitation current calculation unit sets the target frequency to a value higher than the first resonant frequency.

4. 4. The control device for a rotating electric machine according to claim 3, wherein the excitation current calculation unit sets the target frequency so that a value obtained by subtracting the electrical angular frequency when the rotational speed of the rotor becomes a maximum rotational speed from the target frequency is a value higher than the first resonant frequency.

5. 4. The control device for a rotating electric machine according to claim 2, wherein the number of turns of the first winding portion is smaller than the number of turns of the second winding portion.

6. 3. The control device for a rotating electric machine according to claim 1, wherein the excitation current calculation unit sets the target frequency to 1 / 10 or less of a carrier frequency in the inverter.

7. A rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A control program for a rotating electric machine applied to a system including the following: an excitation current calculation step of calculating an excitation current to be passed through the stator winding in order to induce a field current in the field winding; a switch control step of controlling switching of the inverter so as to cause a composite current, in which the excitation current having a frequency higher than that of the fundamental current to be caused to flow through the stator winding is superimposed on the fundamental current to be flowed through the stator winding, to flow through the stator winding; The excitation current calculation step includes: A control program for a rotating electric machine that calculates the excitation current including a lower frequency component (fi-fr) obtained by subtracting the electrical angular frequency (fr) of the rotor from a target frequency (fi) of the field current, and an upper frequency component (fi+fr) obtained by adding the electrical angular frequency to the target frequency (fi).

Images