Rotating machine control device

Abstract

A rotating machine control device is provided that can generate a current command value in a manner that reduces loss without reducing torque while appropriately protecting a rotating machine from heat generation without using a current command map. The rotating machine control device (1000) controls a rotating machine (1) having a stator winding and an excitation winding, and includes a current command generation unit (23) that generates a current command value based on the obtained temperature of the rotating machine (1), the current command generation unit (23) including: a constraint condition setting unit (51) that obtains a constraint condition based on a torque command, a stator winding voltage, a stator winding current, and an excitation winding current; an optimization calculation unit (55) that calculates and outputs the current command value using an evaluation function and constraint conditions set based on the torque command, the stator winding voltage, the stator winding current, and the excitation winding current; and a constraint condition updating unit (53) that updates the constraint condition based on the temperature of the rotating machine and calculates and outputs the current command value using the updated constraint condition.

Description

Technical Field

[0001] The present application relates to a rotating machine control device. Background Art

[0002] When the temperature of the winding rises, the amount of current flowing through the winding is generally reduced in order to protect the rotating machine from overheating.

[0003] For example, the following method is disclosed: according to the temperatures of the stator winding and the excitation winding, multiple current command maps of the stator winding and the excitation winding are maintained, thereby reducing the current command value of the winding with a higher temperature in the stator winding and the excitation winding, and increasing the current command value of the winding with a lower temperature, thereby suppressing the reduction of output torque (for example, refer to patent document 1).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-176114

[0007] Patent Document 2: Japanese Patent No. 4210992 Summary of the invention

[0008] In Patent Document 1, it is necessary to prepare a current command map corresponding to each winding temperature in advance, and the number of parameters (e.g., rotating machine parameters such as the number of revolutions, resistance, inductance, DC voltage, rotation speed, etc.) increases, and the number of possible current command patterns increases exponentially. In particular, in a rotating machine having an excitation winding, since the number of parameters is large, the current command pattern corresponding to the temperature becomes very large, and it is difficult to hold it as a map.

[0009] On the other hand, Patent Document 2 discloses that the current command values ​​of the stator winding and the field winding are updated in accordance with the torque command value so as to minimize the copper loss without using the current command map. However, Patent Document 2 does not have a current command map, but since the temperature information is not considered, when the temperature of the rotating machine rises, it is impossible to suppress the decrease in the output torque and the overheating of the rotating machine.

[0010] The present application discloses a technology for solving the above-mentioned problems, and its object is to obtain a rotating machine control device that can generate a current command value in a manner that reduces loss without reducing torque while appropriately protecting the rotating machine from heat generation without using a current command map.

[0011] The rotating machine control device disclosed in the present application controls a rotating machine having a stator winding and an excitation winding, and the rotating machine control device comprises: a temperature information acquisition unit, which acquires the temperature of the rotating machine; and a current command generation unit, which generates a current command value according to the temperature of the rotating machine obtained by the temperature information acquisition unit, and the current command generation unit comprises: a constraint condition setting unit, which obtains constraint conditions according to various conditions of a torque command, a stator winding voltage, a stator winding current, and an excitation winding current; an optimization operation unit, which calculates and outputs the current command value using an evaluation function set according to the torque command, the stator winding voltage, the stator winding current, and the excitation winding current and the constraint conditions; and a constraint condition updating unit, which updates the constraint conditions according to the temperature of the rotating machine obtained by the temperature information acquisition unit, and calculates and outputs the current command value using the updated constraint conditions.

[0012] According to the rotating machine control device disclosed in the present application, it is possible to obtain a rotating machine control device that can generate a current command value so as to reduce loss without reducing torque while appropriately protecting the rotating machine from heat generation without using a current command map. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a diagram showing a hardware configuration of the rotating machine control device according to the first embodiment.

[0014] Figure 2 This is a block diagram showing the configuration of the rotating machine control device according to the first embodiment.

[0015] Figure 3 This is a block diagram showing a stator winding current control unit according to the first embodiment.

[0016] Figure 4 This is a block diagram showing the field winding current control unit according to the first embodiment.

[0017] Figure 5 This is a block diagram showing a current command generating unit according to the first embodiment.

[0018] Figure 6 1 is a diagram showing conditions of 10 command patterns generated by the current command generating unit.

[0019] Fig. 7A This is a flowchart showing the flow of calculations in the optimization calculation unit according to the first embodiment.

[0020] Figure 7B This is a flowchart showing the flow of calculations in the optimization calculation unit according to the first embodiment.

[0021] Figure 7CThis is a flowchart showing the flow of calculations in the optimization calculation unit according to the first embodiment.

[0022] Figure 8 It is a diagram showing a control example performed by the rotating machine control device according to the first embodiment.

[0023] Fig. 9 It is a diagram showing a control example performed by the rotating machine control device according to the first embodiment.

[0024] (Explanation of Reference Numerals)

[0025] 1: rotating machine; 2: position detector; 3: temperature detector; 4, 5: current detector; 6: stator winding power converter; 7: field winding power converter; 10: processor; 11: storage device; 20: differentiator; 21: stator winding current control unit; 22: field winding current control unit; 23: current command generating unit; 24: temperature information acquiring unit; 30, 40: adder-subtractor; 31, 41: PI controller; 32: dq / uvw coordinate converter; 33: uvw / dq coordinate converter; 34, 42: voltage limiter; 50: rotating machine parameter acquiring unit; 51: constraint condition setting unit; 52: evaluation function setting unit; 53: constraint condition updating unit; 54: evaluation function updating unit; 55: optimization operation unit; 1000: rotating machine control device. DETAILED DESCRIPTION

[0026] Hereinafter, the present embodiment will be described with reference to the accompanying drawings. In addition, in each figure, the same reference numeral represents the same or equivalent part. In addition, as a rotating machine, it is applied to a rotating machine such as an AC generator, a motor or a drive device, but here, as an example, an AC generator mounted on a car is described.

[0027] Implementation method 1.

[0028] Hereinafter, the rotating machine control device according to Embodiment 1 will be described.

[0029] Figure 1 1 is a diagram showing the hardware configuration of the rotating machine control device according to the first embodiment, and shows the entire system including the rotating machine as the control object. In the figure, the rotating machine control device 1000 is a device for driving and controlling the rotating machine 1, and is connected to each winding of the rotating machine 1 via the stator winding power converter 6 and the excitation winding power converter 7 described later. In addition, the rotating machine control device 1000 is connected to the position detector 2 and the temperature detector 3 provided in the rotating machine 1. Furthermore, the rotating machine control device 1000 is connected to the current detectors 4 and 5 respectively connected in series between the stator winding power converter 6, the excitation winding power converter 7 and the rotating machine 1.

[0030] exist Figure 1 In the embodiment, the rotating machine control device 1000 includes a processor 10 and a storage device 11 .

[0031] Although not shown, the storage device 11 includes a volatile storage device such as a random access memory and a nonvolatile auxiliary storage device such as a flash memory. Alternatively, the storage device 11 may include an auxiliary storage device such as a hard disk instead of the nonvolatile auxiliary storage device.

[0032] The processor 10 executes the program input from the storage device 11. The storage device 11 includes an auxiliary storage device and a volatile storage device, so the program is input from the auxiliary storage device via the volatile storage device to the processor 10. In addition, the processor 10 can output data such as calculation results to the volatile storage device of the storage device 11, and can also save data to the auxiliary storage device via the volatile storage device.

[0033] The rotating machine 1 is used, for example, as an on-vehicle AC generator, and although not shown, has a permanent magnet and a field winding in the rotor, and has a three-phase stator winding in the stator. The rotating machine 1 may or may not have a permanent magnet, and may be a rotating machine having two or more stator windings of three or more phases in the stator.

[0034] The position detector 2 is, for example, a resolver, and is provided on the rotating shaft of the rotating machine 1 to detect the angle θ of the rotor. Alternatively, the position detector 2 may be a position estimator that estimates the angle θ of the rotor.

[0035] The temperature detector 3 detects the temperature ts of the stator winding and the temperature tf of the field winding. In addition, the temperature detector 3 may be a temperature estimator that estimates the temperature of the stator winding and the field winding instead of the temperature detector 3. In addition, not only the temperature of the stator winding and the field winding, but also the temperature of the parts constituting the rotating machine such as magnets and the temperature of the power converter and the like may be detected or estimated.

[0036] The current detector 4 detects the currents iu, iv, iw of each phase of the stator winding, and the current detector 5 detects the excitation winding current if. In addition, a current estimator that estimates the currents iu, iv, iw of the stator winding and the excitation winding current if may be used instead of part or both of the current detectors 4 and 5.

[0037] The stator winding power converter 6 generates voltages corresponding to the three-phase voltage command values ​​vu*, vv*, and vw* using a known method such as PWM (Pulse Width Modulation) or PAM (Pulse Amplitude Modulation), and detects the stator winding DC link voltage VDC used in power conversion.

[0038] The field winding power converter 7 generates a voltage corresponding to the voltage command value vf* using a known method such as PWM or PAM, similarly to the stator winding power converter 6. In addition, the field winding DC link voltage VDCf used for power conversion is detected.

[0039] Figure 2 1 is a block diagram showing the functions of the rotating machine control device 1000 according to the first embodiment. Figure 2 In the embodiment, a differentiator 20, a stator winding current control unit 21, an excitation winding current control unit 22, a current command generating unit 23, and a temperature information acquiring unit 24 are provided. Here, each winding has one current control unit, but each current control unit may also be configured to implement non-interference control by taking into account interference between windings using a known method.

[0040] The differentiator 20 differentiates the angle θ of the rotor detected by the position detector 2 to calculate the speed ω of the rotor.

[0041] The stator winding current control unit 21 converts the phase currents iu, iv, iw of the stator winding detected by the current detector 4 into stator winding currents id, iq, so as to make the stator winding currents id, iq consistent with the stator winding current command values ​​id*, iq* calculated by the current command generation unit 23, and calculates the stator winding voltage command values ​​vu*, vv*, vw*.

[0042] The field winding current control unit 22 calculates the field winding voltage command value vf* so that the field winding current if detected by the current detector 5 coincides with the field winding current command value if* calculated by the current command generation unit 23 .

[0043] The temperature information acquisition unit 24 acquires the stator winding temperature ts and the field winding temperature tf detected by the temperature detector 3 .

[0044] The current command generating unit 23 calculates the stator winding current command values ​​id*, iq* and the excitation winding current command value if* based on the torque command T*, the rotor speed ω calculated by the differentiator 20, the stator winding DC link voltage VDC detected by the stator winding power converter 6, the excitation winding DC link voltage VDCf detected by the excitation winding power converter 7, the stator winding temperature ts and the excitation winding temperature tf obtained by the temperature information acquiring unit 24, the stator winding current limit value idqlim, the excitation winding current limit value iflim, the stator winding current id, iq transformed by the stator winding current control unit 21, and the excitation winding current if transformed by the excitation winding current control unit 22.

[0045] Next, the stator winding current control unit 21 will be described.

[0046] Figure 3 1 is a diagram showing the structure of the stator winding current control unit 21 in the rotating machine control device 1000 according to Embodiment 1. In the figure, the stator winding current control unit 21 has an adder-subtractor 30, a PI (Proportional Integral) controller 31, a dq / uvw coordinate converter 32, a uvw / dq coordinate converter 33, and a voltage limiter 34.

[0047] The operation of the stator winding current control unit 21 will be described.

[0048] The uvw / dq coordinate converter 33 converts the three-phase stator winding currents iu, iv, iw detected by the current detector 4 into stator winding current detection values ​​of d-axis current id and q-axis current iq using a known coordinate conversion method.

[0049] The stator winding current command values ​​id*, iq* output from the current command generation unit 23 and the stator winding currents id, iq as current detection values ​​output from the uvw / dq coordinate converter 33 are input to the adder-subtractor 30, and the stator winding current deviations id*-id, iq*-iq are calculated. Based on the calculated stator winding current deviations id*-id, iq*-iq, PI control is performed in the PI controller 31 to generate stator winding voltage command values ​​vd**, vq**.

[0050] Formula (1) and Formula (2) show calculation examples in the PI controller 31. Here, Kpd and Kid, and Kpq and Kiq are proportional gain and integral gain of the stator winding current of each axis. In addition, s is a differential operator of Laplace transform, which is the same in the following formulas.

[0051] vd**=(Kpd+Kid / s)·(id*-id) (1)

[0052] vq**=(Kpq+Kiq / s)·(iq*-iq) (2)

[0053] Here, vd** and vq** are calculated by feedback control, but may be calculated by feedforward control.

[0054] Although not shown in the figure, after the stator winding voltage command values ​​vd** and vq** are generated as described above, a well-known non-interference control may be performed.

[0055] When the amplitude of the input stator winding voltage command values ​​vd** and vq** is greater than the stator winding voltage limit value vdqlim, the voltage limiter 34 calculates the stator winding voltage command values ​​vd* and vq* so as to be equal to or less than the stator winding voltage limit value vdqlim. The stator winding voltage limit value vdqlim is obtained by the product of the stator winding DC link voltage VDC and the voltage utilization factor.

[0056] Although not shown, when the voltage amplitudes of the stator winding voltage command values ​​vd** and vq** are limited by the voltage limiter 34, the anti-saturation process may be performed on the integrator of the PI controller 31. In addition, the voltage limiter 34 limits the stator winding voltage command values ​​vd** and vq**, but the stator winding DC link voltage VDC may be limited instead of the stator winding voltage command values ​​vd** and vq**.

[0057] The dq / uvw coordinate converter 32 converts the stator winding voltage command values ​​vd*, vq* into three-phase voltage command values ​​vu*, vv*, vw* using a known coordinate conversion method.

[0058] Next, the field winding current control unit 22 will be described.

[0059] Figure 4 1 is a diagram showing a configuration of a field winding current control unit 22 in a rotating machine control device 1000 according to Embodiment 1. In the diagram, the field winding current control unit 22 includes an adder-subtractor 40 , a PI controller 41 , and a voltage limiter 42 .

[0060] The operation of the field winding current control unit 22 will be described.

[0061] The field winding current command value if* output from the current command generating unit 23 and the field winding current if detected by the current detector 5 are input to the adder-subtractor 40, and the field winding current deviation if*-if is calculated. Based on the calculated field winding current deviation if*-if, PI control is performed in the PI controller 41 to generate the field winding voltage command value vf**.

[0062] Equation (3) shows a calculation example in the PI controller 41. Here, Kpf and Kif are the field winding proportional gain and integral gain, respectively.

[0063] vf**=(Kpf+Kif / s)·(if*-if) (3)

[0064] Although not shown, after the field winding voltage command value vf** is generated as described above, a known non-interference control may be performed. In addition, the field winding voltage command value vf** is calculated by feedback control here, but it may be calculated by feedforward control.

[0065] When the amplitude of the field winding voltage command value vf** is larger than the field winding voltage limit value vflim, the voltage limiter 42 calculates the field winding voltage command value vf* so as to be equal to or less than the field winding voltage limit value vflim. The field winding voltage limit value vflim is obtained by the product of the field winding DC link voltage VDCf and the voltage utilization factor.

[0066] Although not shown, when the voltage amplitude of the field winding voltage command value vf** is limited by the voltage limiter 42, the anti-saturation process may be performed on the integrator of the PI controller 41. In addition, the voltage limiter 42 limits the field winding voltage command value vf**, but the field winding DC link voltage VDCf may be limited instead of the field winding voltage command value vf**.

[0067] Next, the current command generating unit 23 will be described.

[0068] Figure 5 1 is a diagram showing the structure of the current command generating unit 23 in the rotating machine control device 1000 according to Embodiment 1. In the figure, the current command generating unit 23 includes a rotating machine parameter acquiring unit 50, a constraint condition setting unit 51, an evaluation function setting unit 52, a constraint condition updating unit 53, an evaluation function updating unit 54, and an optimization calculation unit 55.

[0069] The rotating machine parameter acquisition unit 50 acquires the stator winding resistance R, the field winding resistance Rf, the stator winding inductance Ld, Lq, the mutual inductance M between the stator winding and the field winding, and the magnet flux KE as rotating machine parameters based on the stator winding current id, iq converted by the stator winding current control unit 21, the field winding current if detected by the current detector 5, and the stator winding temperature ts and the field winding temperature tf acquired by the temperature information acquisition unit 24. In addition, the rotating machine parameters are updated based on the stator winding temperature ts and the field winding temperature tf acquired by the temperature information acquisition unit 24.

[0070] In addition, the rotating machine parameter acquisition unit 50 may acquire not only the stator winding current id, iq, the field winding current if, the stator winding temperature ts, and the field winding temperature tf, but also the command current or voltage as an independent variable. In addition, as the rotating machine parameter, it is also possible to acquire not only the stator winding resistance R, the field winding resistance Rf, the stator winding inductance Ld, Lq, the mutual inductance M between the stator winding and the field winding, and the magnet flux KE, but also the field winding inductance Lf. In the case of a dual three-phase winding type rotating machine, the mutual inductance between the stators may be set as a rotating machine parameter, and the rotating machine parameter may be expressed not only in inductance but also in flux.

[0071] In the constraint condition setting unit 51, the constraint condition is set based on the torque command T*, the rotor speed ω, the DC link voltages VDC and VDCf, the rotating machine parameters output from the rotating machine parameter acquisition unit 50, and the current command values ​​id*, iq*, and if* output from the optimization calculation unit 55. In addition, in the constraint condition setting unit 51, the detected currents id, iq, and if may be used instead of the current command values ​​id*, iq*, and if*.

[0072] In the evaluation function setting unit 52, an evaluation function is set based on the torque command T*, the rotor speed ω, the DC link voltages VDC and VDCf, the rotating machine parameters output from the rotating machine parameter acquisition unit 50, and the current command values ​​id*, iq*, and if* output from the optimization calculation unit 55. In addition, in the evaluation function setting unit 52, the detected currents id, iq, and if may be used instead of the current command values ​​id*, iq*, and if*, similarly to the constraint condition setting unit 51.

[0073] Next, the method of setting the constraint conditions in the constraint condition setting unit 51 and the method of setting the evaluation function in the evaluation function setting unit 52 will be specifically described below for each of the ten instruction modes.

[0074] In addition, Figure 6The conditions according to the command mode are summarized in . In condition a: torque command limitation, if the torque command is within the range up to the maximum torque command value, it is recorded as 0, and when it reaches the maximum torque command value and is saturated, it is recorded as 1; in condition b: voltage limitation, if the voltage vdq is within the range up to the maximum voltage vdqmax, it is recorded as 0, and when it reaches the maximum voltage vdqmax and is saturated, it is recorded as 1; in condition c: field winding current limitation, if the field winding current if is within the range up to the maximum excitation winding current ifmax, it is recorded as 0, and when it reaches the maximum excitation winding current ifmax and is saturated, it is recorded as 1; in condition d: stator winding current limitation, if the stator winding current id, iq is within the range up to the maximum stator winding current amplitude idqmax, it is recorded as 0, and when it reaches the maximum stator winding current amplitude idqmax and is saturated, it is recorded as 1.

[0075] <Command Mode 1>

[0076] At the operating point, when the torque command can be output and is within the voltage limit, and the stator winding current and the field winding current are within the current limit, the constraint condition is set to equation (4) and the evaluation function is set to equation (5).

[0077] [Mathematical formula 1]

[0078] (L d -L q )i d i q +(K E +Mi f )i q -C T =0 (4)

[0079] [Mathematical formula 2]

[0080]

[0081] Formula (4) represents torque, and formula (5) represents copper loss. Here, CT is obtained by dividing the torque command T* by the number of pole pairs Pn, Pw represents loss, Ld, Lq, and M represent d-axis inductance, q-axis inductance, and mutual inductance between the stator winding and the excitation winding, respectively, and KE represents magnet flux. In addition, the description will be omitted later. Although the evaluation function is described with copper loss as an indicator, it can also be iron loss as other losses, and it can also be an evaluation function with power factor as an indicator. When the power factor is set as the evaluation function, it is set to the maximum power factor.

[0082] By solving id, iq, and if that minimizes equation (5) using equation (4) as a constraint, it is possible to calculate a current command value that minimizes loss under the torque command value. This condition is defined as command pattern 1.

[0083] <Command Mode 2>

[0084] At the operating point, when the torque command can be output, the voltage is within the limit, the stator winding current is within the current limit, and the excitation winding current is saturated, the constraint condition is set to equation (6) and the evaluation function is set to equation (7).

[0085] [Mathematical formula 3]

[0086] (L d -L q )i d i q +(K E +Mf imax )i q -C T =0 (6)

[0087] [Formula 4]

[0088]

[0089] Here, ifmax means the maximum value of the field winding current. When the field winding voltage exceeds the maximum value vfmax of the field winding voltage (vfmax=kf×VDCf, where kf is the voltage utilization factor), ifmax is changed so that the field winding voltage falls within vfmax.

[0090] By using equation (6) as a constraint condition and solving id and iq that minimize equation (7), it is possible to calculate a current command value that minimizes the loss when the field winding current is saturated under the torque command value. In addition, this condition is defined as command mode 2.

[0091] <Command Mode 3>

[0092] At the operating point, when the torque command can be output, the voltage is within the limit, the excitation winding current is within the current limit, and the stator winding current is saturated, the constraint condition is set to equation (8) and the evaluation function is set to equation (9).

[0093] [Mathematical formula 5]

[0094]

[0095] [Mathematical formula 6]

[0096]

[0097] Here, idqmax means the maximum value of the stator winding current amplitude.

[0098] By using equation (8) as a constraint condition and solving id and if to minimize equation (9), it is possible to calculate a current command value that minimizes the loss when the stator winding current is saturated under the torque command value. In addition, this condition is defined as command mode 3.

[0099] <Command Mode 4>

[0100] At the operating point, when the torque command cannot be output, the voltage is within the limit, and the stator winding current and the field winding current are saturated, the constraint condition is set to equation (10) and the evaluation function is set to equation (11).

[0101] [Mathematical formula 7]

[0102]

[0103] [Mathematical formula 8]

[0104]

[0105] By solving the id that maximizes the equation (11) using equation (10) as a constraint condition, it is possible to calculate the current command value that gives the maximum torque when the stator winding current and the field winding current are saturated. This condition is defined as command mode 4.

[0106] <Command Mode 5>

[0107] At the operating point, when the torque command can be output, the voltage is saturated, and the stator winding current and the excitation winding current are within the current limit, the constraint conditions are set to equations (12) and (13), and the evaluation function is set to equation (14).

[0108] [Mathematical formula 9]

[0109] (L d -L q )i d i q +(K E +Mi f )i q -C T =0 (12)

[0110] [Formula 10]

[0111]

[0112] [Mathematical formula 11]

[0113]

[0114] Formula (13) is obtained by dividing the stable voltage of the rotating machine by the angular velocity ωre, and CV means the result obtained by dividing the voltage limit value vdqmax (vdqmax=k×VDC, where k is the voltage utilization rate) by the angular velocity ωre.

[0115] By setting equations (12) and (13) as constraint conditions and solving id, iq, and if that minimize equation (14), it is possible to calculate a current command value that minimizes the loss when the voltage is saturated under the torque command value. In addition, this condition is defined as command mode 5.

[0116] <Command Mode 6>

[0117] At the operating point, when the torque command can be output, the voltage is saturated, the stator winding current is within the current limit, and the excitation winding current is saturated, the constraints are set to equations (15) and (16), and no evaluation function is set. In this case, id, iq, and if that satisfy equations (15) and (16) as constraint conditions are obtained.

[0118] [Mathematical formula 12]

[0119]

[0120] [Mathematical formula 13]

[0121]

[0122] By solving id and iq using equations (15) and (16) as constraint conditions, it is possible to calculate the current command value when the voltage is saturated and the field winding current is saturated under the torque command value. In addition, this condition is defined as command mode 6.

[0123] <Command Mode 7>

[0124] At the operating point, when the torque command can be output, the voltage is saturated, the stator winding current is saturated, and the excitation winding current is within the current limit, the constraint conditions are set to equations (17) and (18), and no evaluation function is set.

[0125] [Formula 14]

[0126]

[0127] [Mathematical formula 15]

[0128]

[0129] By solving id and if using equations (17) and (18) as constraint conditions, it is possible to calculate the current command value when the voltage is saturated and the stator winding current is saturated under the torque command value. In addition, this condition is defined as command mode 7.

[0130] <Command Mode 8>

[0131] At the operating point, when the torque command cannot be output, the voltage is saturated, the stator winding current is within the current limit, and the excitation winding current is saturated, the constraint condition is set to equation (19) and the evaluation function is set to (20).

[0132] [Formula 16]

[0133]

[0134] [Mathematical formula 17]

[0135]

[0136] By solving id and iq that maximize equation (20) using equation (19) as a constraint, it is possible to calculate the current command value that gives the maximum torque when the voltage is saturated and the field winding current is saturated. This condition is defined as command mode 8.

[0137] <Command Mode 9>

[0138] At the operating point, when the torque command cannot be output, the voltage is saturated, the stator winding current is saturated, and the excitation winding current is within the current limit, the constraint condition is set to equation (21) and the evaluation function is set to (22).

[0139] [Mathematical formula 18]

[0140]

[0141] [Mathematical formula 19]

[0142]

[0143] By setting equation (21) as a constraint condition and solving id and if so as to maximize equation (22), it is possible to calculate the current command value that gives the maximum torque when the voltage is saturated and the stator winding current is saturated. In addition, this condition is defined as command mode 9.

[0144] <Command Mode 10>

[0145] At the operating point, when the torque command cannot be output, the voltage is saturated, and the stator winding current and the excitation winding current are saturated, the constraint condition is set to equation (23) and the evaluation function is set to (24).

[0146] [Mathematical formula 20]

[0147]

[0148] [Mathematical formula 21]

[0149]

[0150] By setting equation (23) as a constraint condition and solving equation (24) to maximize id, it is possible to calculate the current command value that gives the maximum torque when the voltage is saturated and the stator winding current and the field winding current are saturated. In addition, this condition is defined as command mode 10.

[0151] As described above, by setting the conditions of command modes 1 to 10, the constraint conditions and evaluation functions of all operating points based on the speed and torque of the rotating machine can be set. Thus, by setting the constraint conditions and evaluation functions from command modes 1 to 10 according to the conditions of the torque command, stator winding voltage, stator winding current, and field winding current, and solving the constraint conditions and evaluation functions, the current command value that minimizes the loss or maximizes the torque can be calculated.

[0152] In addition, from command mode 1 to 10, the formulas expressing torque and voltage are expressed by inductance, but it can be expressed not only by inductance but also by magnetic flux. In addition, inductance and magnetic flux become functions of current, so when expressed as functions of current, magnetic saturation can be considered, and the calculation accuracy is improved. Moreover, magnet magnetic flux and winding resistance are parameters that change according to temperature, so they can also be expressed as functions of temperature or current, and the calculation accuracy can be improved in the same way.

[0153] <Updating of Constraints and Evaluation Functions>

[0154] exist Figure 5 In the constraint condition updating unit 53 , the constraint condition is updated based on the constraint condition from the constraint condition setting unit 51 and the stator winding temperature ts and the field winding temperature tf from the temperature detector 3 .

[0155] The evaluation function updating unit 54 updates the evaluation function based on the evaluation function from the evaluation function setting unit 52 and the stator winding temperature ts and the field winding temperature tf from the temperature detector 3 .

[0156] Next, the specific operation of the constraint condition updating unit 53 and the evaluation function updating unit 54 will be described. The stator winding current limit value idqlim and the field winding current limit value iflim are calculated so that the stator winding temperature ts and the field winding temperature tf detected by the temperature detector 3 do not exceed the stator winding temperature maximum value tsmax and the field winding temperature maximum value tfmax. When the stator winding current limit value idqlim is less than the stator winding current amplitude maximum value idqmax set for overcurrent protection, the constraint condition from the constraint condition setting unit 51 and the idqmax in the evaluation function from the evaluation function setting unit 52 are replaced with idqlim.

[0157] Similarly, when the field winding current limit value iflim is smaller than the field winding current maximum value ifmax set for overcurrent protection, ifmax in the constraint condition from the constraint condition setting unit 51 and the evaluation function from the evaluation function setting unit 52 is replaced with iflim. As described above, by replacing the current maximum values ​​for overcurrent protection of the stator winding and the field winding in the constraint condition and the evaluation function with the current limit value for overheat protection, it is possible to set the constraint condition and the evaluation function in consideration of the stator winding temperature ts and the field winding temperature tf that always change in accordance with the operation for all operation points based on the speed and torque of the rotating machine.

[0158] Here, an example is shown in which the stator winding current limit value idqlim and the field winding current limit value iflim are obtained based on the stator winding temperature ts and the field winding temperature tf, but the stator winding current limit value idqlim and the field winding current limit value iflim may be obtained based on the temperature of the parts constituting the rotating machine such as the magnet or the temperature of the power converter, etc., instead of the stator winding temperature ts and the field winding temperature tf. In particular, when the temperature of the magnet is used, basically only the field winding temperature tf may be replaced with the magnet temperature, and the field winding current limit value iflim may be limited based on the magnet temperature.

[0159] In addition, the limit value is not limited to the current. For example, the stator winding voltage maximum value vdqmax and the field winding voltage maximum value vfmax may be used and replaced with the stator winding voltage limit value vdqlim and the field winding voltage limit value vflim according to the detected stator winding temperature ts and the field winding temperature tf.

[0160] In the present embodiment, the constraint conditions and the evaluation function are updated based on the detected temperature information. However, the constraint conditions and the evaluation function may be updated based on the power consumption or the power-on time instead of the temperature.

[0161] <Optimization calculation unit>

[0162] exist Figure 5 In the optimization operation unit 55, based on the constraints and evaluation functions updated in the constraint updating unit 53 and the evaluation function updating unit 54, the optimization problem with constraints is solved so that the evaluation function becomes the minimum or maximum, and the instruction mode closest to the conditions is selected, thereby obtaining the current instruction values ​​id*, iq*, if*. Specifically, according to Fig. 7A , Figure 7B as well as Figure 7C The flowchart shown in the figure determines which of the above command modes is selected based on the current limit, voltage limit, or torque output limit judgment formula. The current limit, voltage limit, and torque output limit judgment formula are always updated based on the detected temperature information.

[0163] Next, according to Fig. 7A , Figure 7B as well as Figure 7C The flowchart shown illustrates a method for determining which instruction mode is in an action point.

[0164] First, in Fig. 7A In the optimization operation unit 55, according to the torque command, the stator winding current command values ​​id*, iq* and the excitation winding current command value if* are generated, and current flows through the stator winding and the excitation winding. At the time point when the current starts to flow through the stator winding and the excitation winding, that is, in step S101, the state is in command mode 1. During the power-on process, the temperature of the winding rises. Due to this temperature rise, although the excitation winding current if is within the limit range ("Yes" in step S102), when the stator winding current id and iq are saturated ("No" in step S103), switch to command mode 3 (step S104). During the operation in command mode 3, if the excitation winding current if is saturated ("No" in step S105), switch to command mode 4 (step S106).

[0165] During the operation in command mode 1 (step S101), if the field winding current if is saturated ("No" in step S102), but the stator winding currents id and iq are within the limit range ("Yes" in step S107), switch to command mode 2 (step S108). During the operation in command mode 2, if the stator winding currents id and iq are saturated ("No" in step S109), switch to command mode 4 (step S106).

[0166] When the field winding current if is saturated ("No" in step S102) and the stator winding currents id and iq are saturated ("No" in step S107) in the operation process of command mode 1 (step S101), switch to command mode 4 (step S106).

[0167] When the voltage vdq is saturated during the operation in the command mode from the command mode 2 to the command mode 4 ("No" in step S110), the control is switched to the command mode 5 (step S111).

[0168] When the voltage vdq is within the limit and can be controlled from command mode 2 to command mode 4 ("Yes" in step S110), the control in the command mode is continued.

[0169] exist Figure 7B In the process of operating in instruction mode 5, when the excitation winding current if becomes within the limit range ("Yes" in step S112), and the stator winding currents id and iq also become within the limit range ("Yes" in step S113), control under instruction mode 5 continues.

[0170] When the field winding current if is within the limit range ("Yes" in step S112) and the stator winding currents id and iq are saturated ("No" in step S113) during operation in command mode 5, switch to command mode 7 (step S114).

[0171] When the field winding current if is saturated ("No" in step S112) while operating in command mode 5, but the stator winding currents id and iq are within the limit range ("Yes" in step S116), switch to command mode 6 (step S117).

[0172] When the field winding current if is saturated ("No" in step S112) and the stator winding currents id and iq are also saturated ("No" in step S116) during operation in command mode 5, switch to command mode 10 (step S125).

[0173] When the torque output T can be output according to the torque command T* during operation in the command mode 6 or the command mode 7 (YES in step S115), the control in the command mode is continued.

[0174] When the torque output T cannot be output according to the torque command T* during operation in command mode 6 or command mode 7 ("No" in step S115), the process is transferred to Figure 7C The next judgment in .

[0175] Even if the torque output T cannot be output according to the torque command T* during operation in command mode 6 or command mode 7 ("No" in step S115), when the excitation winding current if is within the limit range ("Yes" in step S118) and the stator winding currents id and iq are also within the limit range ("Yes" in step S119), control under command mode 6 or 7 continues.

[0176] When the torque output T cannot be output according to the torque command T* ("No" in step S115), when the excitation winding current if becomes within the limit range ("Yes" in step S118), and when the stator winding currents id and iq are saturated ("No" in step S119), switch to command mode 9 (step S120).

[0177] When the torque output T cannot be output according to the torque command T* ("No" in step S115), when the excitation winding current if is saturated ("No" in step S118), but the stator winding currents id and iq are within the limit range ("Yes" in step S122), switch to command mode 8 (step S123).

[0178] When the stator winding currents id and iq are saturated during operation in instruction mode 8 ("No" in step S124), and when the excitation winding current if is saturated during operation in instruction mode 9 ("No" in step S121), switch to instruction mode 10 (step S125).

[0179] As described above, the current command generating unit 23 has a plurality of constraint conditions and evaluation function groups of a plurality of command modes corresponding to the conditions of the torque command, the stator winding voltage, the stator winding current and the excitation winding current, and can select appropriate command modes one by one according to the conditions and update the constraint conditions and the evaluation function.

[0180] Regarding the operations in each instruction mode, considering the operation load, Lagrange's undetermined multiplier method is used in advance to functionalize the optimization problem with constraints. The function obtained by Lagrange's undetermined multiplier method is derived as a system of equations, so for each control cycle set by a recursive numerical solution based on Newton's method, the current command values ​​id*, iq*, if* are obtained. In addition, if the partial differential process used in the derivation of the solution based on Lagrange's undetermined multiplier method and Newton's method is functionalized in advance, the operation load is reduced, but it is not necessary to functionalize it in advance when there is a surplus of processors. It can also be a structure that solves the optimization problem with constraints for each set control cycle.

[0181] By making the current command generating unit 23 have the above structure, even if there is no mapping of the current command value based on the speed, torque, stator winding temperature, and excitation winding temperature of the rotating machine, it is possible to protect the rotating machine from overheating and generate a torque command or a current command value that becomes the maximum torque while minimizing the loss.

[0182] Next, the effects of this embodiment will be described. Figure 8 The current amplitude, temperature, and torque behavior of each winding corresponding to the operation of the current limit value and the current command value when the field winding temperature rises and the field winding temperature is protected are shown. Fig. 9 The current amplitude, temperature, and torque behavior of each winding corresponding to the action of the current limit value and the current command value when the stator winding temperature rises and the stator winding temperature is protected are shown. Here, as a simple example, the instruction mode 1 in which the stator winding current, the excitation winding current, and the voltage are not saturated is described.

[0183] First, use Figure 8 Describes the situation of protecting the excitation winding temperature.

[0184] Based on the torque command, the optimization operation unit 55 generates stator winding current command values ​​id*, iq* and field winding current command value if*, and current flows through the stator winding and field winding. During the energization process, the temperature of the winding rises. Figure 8 In the process, the excitation winding temperature tf rises significantly, but the constraint condition is updated in the constraint condition updating unit 53 according to the excitation winding temperature tf, and the evaluation function is updated in the evaluation function updating unit 54, so that the excitation winding temperature tf does not exceed the maximum excitation winding temperature tfmax, and the excitation winding current limit value iflim is reduced.

[0185] When the field winding current limit value iflim reaches the field winding current command value if*, that is, at the time t1 when iflim≤if*, in the optimization operation unit 55, the command mode is switched from command mode 1 to command mode 2. The field winding current command value if* is limited to prevent overheating of the field winding, and for the stator winding whose temperature is within the limit range, the stator winding current command values ​​id* and iq* are generated in such a way that the evaluation function is minimized under the constraint conditions of command mode 2. Here, the constraint conditions refer to if=iflim and the torque output T=T*. By controlling in this way, overheating of the field winding can be prevented and the reduction of torque can be suppressed.

[0186] In addition, Figure 8In the example, for simplicity, the current is described as the current amplitude, but the current phase usually also changes. When iflim≤if*, the command mode is switched from command mode 1 to command mode 2 by the optimization operation unit 55, but at this time, the field winding current command value if* is limited in consideration of the current phase to prevent overheating of the field winding, and for the stator winding whose temperature is within the limit range, the current command values ​​id* and iq* are generated in such a way that the evaluation function is minimized under the constraint conditions of command mode 2.

[0187] Next, use Fig. 9 Describes the situation of protecting the stator winding temperature.

[0188] Based on the torque command, the optimization operation unit 55 generates stator winding current command values ​​id*, iq* and field winding current command value if*, and current flows through the stator winding and field winding. During the energization process, the temperature of the winding rises. Fig. 9 In the process, the stator winding temperature ts rises significantly, but the constraint condition is updated in the constraint condition updating unit 53 according to the stator winding temperature ts, and the evaluation function is updated in the evaluation function updating unit 54, so that the stator winding temperature ts does not exceed the stator winding temperature maximum value tsmax, and the stator winding current limit value idqlim is reduced.

[0189] When the stator winding current limit value idqlim reaches the stator winding current command value idq* (the stator winding current command value id* or the stator winding current command value iq* is recorded as idq*), that is, at the time t2 when idqlim≤idq* is reached, the command mode is switched from command mode 1 to command mode 3 in the optimization operation unit 55. The stator winding current command value idq* is limited to prevent overheating of the stator winding, and for the excitation winding whose temperature is within the limit range, the current command value if* is generated in such a way that the evaluation function is minimized under the constraint conditions of command mode 3. Here, the constraint conditions refer to idq (id or iq) = idqlim and torque output T = T*. By controlling in this way, it is possible to prevent overheating of the excitation winding and suppress the reduction of torque (the stator winding current id or the stator winding current iq is recorded as idq).

[0190] In addition, Fig. 9In the example, for simplicity, the current is described as the current amplitude, but the current phase usually also changes. When idqlim≤idq*, the command mode is switched from command mode 1 to command mode 3 by the optimization operation unit 55, but at this time, the stator winding current command value idq* is limited in consideration of the current phase to prevent overheating of the stator winding, and the current command value if* is generated for the field winding whose temperature is within the limit range in such a way that the evaluation function is minimized under the constraint conditions of command mode 3.

[0191] like Figure 8 as well as Fig. 9 As shown, when the torque T corresponding to the torque command T* can be output under the current limitation of either the field winding or the stator winding, the torque command can be maintained. However, when the torque command T* cannot be output physically, the current command value can be generated so as to obtain the maximum torque.

[0192] In the above Figure 8 as well as Fig. 9 In the example of switching command modes 1 to 3, there are actually more command modes, depending on the operating point based on the torque, the number of revolutions, or the temperature of the rotating machine. Figures 7A to 7C The flowchart shown in the figure switches the command mode and performs the operation.

[0193] As described above, according to the first embodiment, the constraint conditions related to the torque output and the evaluation function related to the loss are optimized based on the obtained temperature information of the rotating machine, and the constraint conditions and the evaluation function are updated based on the obtained temperature information of the rotating machine, and the current commands of the stator winding and the field winding are calculated, so that the optimization calculation can be performed based on the temperature information of the rotating machine. Therefore, it is possible to protect the rotating machine from overheating when the winding temperature rises, and to suppress the torque reduction and reduce the loss without using the current command map.

[0194] The rotating machine control device involved in embodiment 1 controls the rotating machine in a manner that protects against overheating when the winding temperature rises, suppresses torque reduction, and reduces losses. Therefore, it is suitable for controlling rotating machines installed in automobiles that are required to suppress torque reduction and reduce losses despite severe temperature environments.

[0195] In addition, in the above-mentioned embodiment, the stator winding temperature ts and the excitation winding temperature tf are used as the temperatures, but as long as it is a rotating machine using magnets, the magnet temperature can also be used instead of the excitation winding temperature tf, and the same effect can be obtained by protecting two or more parts among the stator winding temperature ts, the excitation winding temperature tf, and the magnet temperature.

[0196] In addition, in a configuration in which a rotating machine having two sets of stator windings is provided as a dual three-phase winding type rotating machine instead of a rotating machine having stator windings and field windings, the same effect as that of the present embodiment can be obtained by generating two sets of current commands based on the temperatures of the two sets of stator windings. Furthermore, even a dual three-phase winding type rotating machine having field windings can obtain the same effect.

[0197] In addition, even if the constraint conditions and evaluation functions are changed based on the power consumption of the rotating machine calculated from the product of the DC voltage and DC current or the product of the torque and the number of revolutions of each power converter instead of the temperature of each part, the same effect can be obtained. Furthermore, even if a timer for counting the control cycle is provided instead of the temperature of each part and the constraint conditions and evaluation functions are changed based on the measured energization time of the stator winding and the excitation winding, the same effect can be obtained.

[0198] The present disclosure describes various exemplary embodiments and examples, but various features, schemes, and functions described in one or more embodiments are not limited to application in specific embodiments and can be applied to the embodiments alone or in various combinations.

[0199] Therefore, within the scope of the technology disclosed in the present specification, numerous modifications not shown in the examples are conceivable, including, for example, modifying, adding or omitting at least one component, or extracting at least one component and combining it with components of other embodiments.

Claims

1. A rotating machine control device for controlling a rotating machine having a stator winding and an excitation winding, the rotating machine control device comprising: a temperature information acquisition unit that acquires the temperature of the rotating machine; and a current command generating unit that generates a current command value based on the temperature of the rotating machine acquired by the temperature information acquiring unit, The current command generating unit includes: The constraint condition setting unit obtains the constraint condition based on the torque command, the stator winding voltage, the stator winding current and the field winding current; an optimization calculation unit that calculates and outputs the current command value using an evaluation function set according to the torque command, the stator winding voltage, the stator winding current, and the field winding current and the constraint condition; and a constraint condition updating unit that updates the constraint condition based on the temperature of the rotating machine acquired by the temperature information acquiring unit, Using the updated constraint conditions, the current command value is calculated and output.

2. The rotating machine control device according to claim 1, wherein: The constraint condition updating unit changes a current limit value of the stator winding and a current limit value of the field winding according to the acquired temperature of the rotating machine, thereby updating the constraint condition.

3. The rotating machine control device according to claim 1, wherein: The constraint condition updating unit changes a voltage limit value of the stator winding and a voltage limit value of the field winding according to the acquired temperature of the rotating machine, thereby updating the constraint condition.

4. The rotating machine control device according to any one of claims 1 to 3, wherein: The current command generating unit pre-has a plurality of constraint conditions and evaluation function groups based on the torque command, the stator winding voltage, the stator winding current and the field winding current. The constraint conditions and the evaluation function are updated by selecting from the pre-set constraint conditions and the evaluation function groups according to the obtained temperature of the rotating machine.

5. The rotating machine control device according to any one of claims 1 to 4, wherein: The optimization calculation unit calculates and outputs the current command value using the evaluation function updated according to the acquired temperature of the rotating machine and the updated constraint condition.

6. The rotating machine control device according to any one of claims 1 to 5, wherein: The current command generating unit includes a rotating machine parameter acquiring unit that acquires a rotating machine parameter indicating a characteristic of the rotating machine, updates the rotating machine parameter based on the acquired temperature of the rotating machine, and describes the constraint condition and the evaluation function using the rotating machine parameter.

7. The rotating machine control device according to any one of claims 1 to 6, wherein: When copper loss or iron loss, which is a loss of the rotating machine, is used as an index, the evaluation function is set so as to minimize the index.

8. The rotating machine control device according to any one of claims 1 to 6, wherein: When the torque output or the power factor of the rotating machine is used as an index, the evaluation function is set so as to maximize the index.

9. The rotating machine control device according to any one of claims 1 to 8, wherein: The rotating machine includes a magnet in a rotor, and a temperature of the rotating machine is at least one of the stator winding, the field winding, and the magnet.

10. The rotating machine control device according to any one of claims 1 to 9, characterized in that: The rotating machine is mounted on a vehicle.

11. A rotating machine control device for controlling a rotating machine having a stator winding and a field winding, wherein: A current command generating unit is provided, the current command generating unit generating a current command value according to the power consumption of the rotating machine or the energization time of the stator winding and the field winding, The current command generating unit includes: A constraint condition setting unit obtains the constraint condition based on the torque command, the stator winding voltage, the stator winding current and the field winding current; an optimization calculation unit that calculates and outputs the current command value using an evaluation function set according to the torque command, the stator winding voltage, the stator winding current, and the field winding current and the constraint condition; as well as a constraint condition updating unit that updates the constraint condition according to the power consumption of the rotating machine or the energization time of the stator winding and the field winding, Using the updated constraint conditions, the current command value is calculated and output.

12. The rotating machine control device according to claim 11, characterized in that: The rotating machine is mounted on a vehicle.

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