JP2007020371A - Method of controlling inverter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent breakdown of an inverter which generates a compound current for driving a rotary electric machine of double spindle multilayer structure. <P>SOLUTION: A current command value is set such that two rotors can be controlled within a controllable power supply voltage range by looking up a table on which the relationship of currents to be commanded for various conditions of the d-axis and q-axis currents of inner rotor and outer rotor, the r.p.m. of inner rotor and outer rotor, the DC voltage, and the like, is prepared previously. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for controlling an inverter device that generates a composite current composed of two different waveforms for driving a rotating electrical machine including a stator, and an inner rotor and an outer rotor provided coaxially inside and outside the stator. It is about.

As a conventional coaxial motor, an inner rotor and an outer rotor are arranged on the inner and outer circumferences with a cylindrical stator sandwiched between them, and a composite current is passed through a multiphase coil wound around the stator, so that the inner rotor and the outer rotor are made independent. A rotating electrical machine having a multi-axis multilayer structure that can be controlled in rotation is known (see, for example, Patent Document 1). In such a rotary electric machine having a multi-axis multilayer structure, an inner rotor and an outer rotor can be rotated independently by supplying a composite current composed of two different waveforms to a stator via an inverter device.
JP 2001-103717 A

  By the way, an inverter device that generates a composite current for driving a rotating electrical machine having two rotors inside and outside cannot follow the target value when the power supply voltage is insufficient due to an increase in the current command value. There is a concern that the risk of control failure resulting from exceeding the controllable power supply voltage range due to the relationship between the operating point and the rotational speed is further increased as compared with the case of driving a single motor. Therefore, in order to avoid control failure and continue to control the two rotors within the maximum voltage range that can be controlled at that time, it is necessary to reduce the current command values of the inner rotor and the outer rotor at a certain rate, respectively. .

  The present invention has been made in view of such problems, and an object of the present invention is to prevent control failure of an inverter device that generates a composite current for driving a rotary electric machine having a multi-axis multilayer structure. An object of the present invention is to provide a method for controlling an inverter device.

  In order to achieve the above object, a first invention provides a control method for an inverter device for generating a current that combines two different sine waves for driving a rotating electrical machine having two rotors inside and outside. The current command value is set to a predetermined value so that the rotor can be controlled within a controllable power supply voltage range.

  A second invention is characterized in that, in the first invention, the current command value is set so as to equally reduce the voltage applied to each rotor.

  A third invention is characterized in that, in the first or second invention, the current command value is limited by setting a limit when the maximum voltage value of a power supply is exceeded with respect to the current command value. To do.

  According to a fourth invention, in the first, second or third invention, a relationship between current command values for various conditions is prepared in advance as a table, and the current command value is obtained by looking up the table. It is characterized by being set to a predetermined value.

  According to a fifth invention, in the first, second or third invention, a predicted value of a composite voltage is calculated from a current command value of the rotor, a rotational speed of the rotor and a motor parameter, and the predicted value is a voltage value of a power source. The current command value is calculated so as not to exceed.

  A sixth invention is characterized in that, in the first or second invention, when the maximum voltage value of the power supply is exceeded, the excess is fed back and a difference from the current command value is obtained.

  The seventh invention compares the composite voltage command value of each phase with the voltage value of the power supply in the first or second invention, and the composite voltage command value of each phase exceeds the voltage value of the power supply Is characterized in that the deviation between the target value and the command value of each phase voltage is calculated and fed back, and the deviation is subtracted from the actual current command value.

  In an eighth aspect of the first or second aspect of the present invention, the dq-axis composite voltage command value is compared with the power supply voltage value, and the dq-axis composite voltage command value exceeds the power supply voltage value. Is characterized in that the deviation between the target value of the dq-axis voltage and the command value is calculated and fed back, and the deviation is subtracted from the actual current command value.

  According to the first invention, it is possible to prevent control failure of the inverter device that generates the composite current, and at this time, it is possible to arbitrarily control the correction ratio of the current value for driving each rotor.

  According to the second invention, when it is not necessary to set the correction ratio for each operating point, the process of calculating the correction ratio can be omitted.

  According to the third aspect of the present invention, it is possible to easily prevent control failure of the inverter device only by adding means for setting a limit for the command value.

  According to the fourth aspect of the invention, since only the current command value is set by looking up a table in which controllable command values are prepared, there is no need to perform complicated calculations.

  According to the fifth aspect, it is not necessary to prepare a table in which controllable command values are prepared, and a large amount of memory is not required.

  According to the sixth aspect of the present invention, it is possible to easily prevent control failure of an inverter device only by adding a means for comparing the excess or deficiency of the power supply voltage to an inverter control device for supplying a composite current. Can do.

  According to the seventh aspect of the invention, it is possible to easily prevent control failure of the inverter device only by adding a means for calculating and feeding back a deviation from the target value.

  According to the eighth aspect, it is possible to reduce the calculation processing when calculating the deviation as compared with the seventh aspect.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall view of a hybrid drive unit to which a multi-axis multilayer motor as an example of a rotating electrical machine to be driven by an inverter device is applied. In FIG. 1, E is an engine, M is a multi-shaft multilayer motor, G is a Ravigneaux type planetary gear train, D is a drive output mechanism, 1 is a motor cover, 2 is a motor case, 3 is a gear housing, 4 is a front cover is there.

  The engine E is a main power source of the hybrid drive unit, and the engine output shaft 5 and the second ring gear R2 of the Ravigneaux type planetary gear train G are connected via a rotation fluctuation absorbing damper 6 and a multi-plate clutch 7. ing.

  The multi-axis multilayer motor M is a sub-power source having two motor generator functions although it is one motor in appearance. This multi-shaft multilayer motor M is fixed to the motor case 2 and has a stator S as a fixed armature wound with a coil, an inner rotor IR disposed inside the stator S and embedded with permanent magnets, and the stator The outer rotor OR, which is disposed outside the S and has a permanent magnet embedded therein, is arranged in three layers on the same axis. A first motor hollow shaft 8 fixed to the inner rotor IR is connected to a first sun gear S1 of a Ravigneaux type planetary gear train G, and a second motor shaft 9 fixed to the outer rotor OR is a Ravigneaux type planetary gear. It is connected to the second sun gear S2 of the row G.

  The Ravigneaux-type compound planetary gear train G is a planetary gear mechanism having a continuously variable transmission function that changes the gear ratio steplessly by controlling two motor rotation speeds. The Ravigneaux type planetary gear train G includes a common carrier C that supports the first pinion P1 and the second pinion P2 that mesh with each other, a first sun gear S1 that meshes with the first pinion P1, and a second sun gear that meshes with the second pinion P2. It has five rotational elements of S2, a first ring gear R1 that meshes with the first pinion P1, and a second ring gear R2 that meshes with the second pinion P2. A multi-plate brake 10 is interposed between the first ring gear R1 and the gear housing 3. An output gear 11 is connected to the common carrier C.

  The drive output mechanism D includes an output gear 11, a first counter gear 12, a second counter gear 13, a drive gear 14, a differential 15, and drive shafts 16 and 16. The output rotation and output torque from the output gear 11 pass through the first counter gear 12, the second counter gear 13, the drive gear 14, and the differential 15, and are transmitted from the drive shafts 16 and 16 to the drive wheels (not shown). The

  That is, the hybrid drive unit connects the second ring gear R2 and the engine output shaft 5, connects the first sun gear S1 and the first motor hollow shaft 8, and connects the second sun gear S2 and the second motor shaft 9 to each other. And the output gear 11 is connected to the common carrier C.

  FIG. 2 is a block diagram illustrating an example of an inverter control device that controls an inverter device for driving a rotating electrical machine including two rotors inside and outside. In this example, an example is described in which the inner rotor is driven with a six-phase current and the outer rotor is driven with a three-phase current. The phase current separation means 27 separates the phase current value of the motor 33 detected by the current sensor 32 into an inner rotor portion and an outer rotor portion, and the 6φ → dq axis conversion means 25 converts the inner 6 phase current value into a dq axis current. The 3φ → dq axis conversion means 26 converts the outer three-phase current value into a dq axis current value.

  When the inner dq axis current target value is given, the inner PI control means 21 performs current PI control so that the actual dq axis current value from the 6φ → dq axis conversion means 25 approaches the inner dq axis current target value, The inner dq axis voltage command value is calculated. Further, when the outer dq axis current target value is given, the outer PI control means 22 performs current PI control so that the actual dq axis current value approaches the outer dq axis current target value, and sets the outer dq axis voltage command value. Calculate. The dq axis → 6φ conversion means 23 converts the inner dq axis voltage command value into an inner 6 phase voltage command value, and the dq axis → 3φ conversion means 24 converts the outer dq axis voltage command value into an outer three phase voltage command value. To do.

  The adding means 28 adds the inner 6-phase voltage command value and the outer 3-phase voltage command value, and the duty generating means 29 generates the duty of each phase. The gate signal generation unit 30 generates a PWM signal for controlling the P side and the N side of the inverter device 31 from the signal generated by the duty generation unit 29 and drives the inverter device 31.

  FIG. 3 is a control flowchart showing a normal control method of the inverter control device. In the flowchart shown in FIG. 3, the inverter control device first reads each phase current from six current sensors installed on six power supply lines connecting the inverter device and the motor. Subsequently, the six-phase alternating current for the inner rotor and the three-phase alternating current for the outer rotor are separated from each phase current by the phase current separating means (step 130). In this example, in order to make the separated 6-phase alternating current and 3-phase alternating current coincide with the current command value, two current control systems are provided.

  First, the current control system converts the obtained 6-phase current for the inner rotor and 3-phase current for the outer rotor into dq-axis currents (steps 140 and 150). Current control is performed so that the converted dq-axis current matches the dq-axis current command value without deviation (steps 160 and 170), and the dq-axis voltage command value for the inner rotor and the dq-axis voltage command value for the outer rotor are set. Calculate. Subsequently, the calculated dq-axis voltage command value for the inner rotor and the dq-axis voltage command value for the outer rotor are converted into a six-phase voltage for the inner rotor and a three-phase voltage for the outer rotor, respectively (steps 180 and 190). ). Finally, the phase voltages of the two rotors are added to generate a composite voltage command value (step 200), a PWM signal is generated (step 230), and the generated PWM signal is supplied to the inverter device.

  The present invention provides a control method of an inverter device for generating a composite current that can be driven without causing a control failure of an inner rotor and an outer rotor for a rotating electrical machine having the multi-axis multilayer structure described above. Hereinafter, the control method of the inverter apparatus of this invention is demonstrated in detail.

  FIG. 4 is a part of a control flowchart showing Example 1 of the control method of the inverter device of the present invention. The first embodiment of the present invention is obtained by replacing the broken line portion A in FIG. 3 with step 100 in FIG. In the first embodiment of the present invention, the relationship between the current values to be commanded for each condition such as the dq axis current values of the inner rotor and the outer rotor, the rotational speeds of the inner rotor and the outer rotor, and the DC voltage is prepared in advance as a table. The current command value is set by looking up the table (step 100), and then the processing of steps 130 to 230 in FIG. 3 is performed. In the above table, in the case of a condition that does not fall within the range of the DC voltage, a limited current command value is set as the return value.

The following two examples are shown as examples of the table.
1. When the correction ratios of the inner current command value and the outer current command value are made equal FIG. 5 is a conceptual diagram of the table. When the inner rotor driving voltage is 80% of the inverter driving voltage and the outer rotor driving voltage is 40%, a shortage of 20% occurs with respect to the power supply voltage. In this case, the current command value is corrected so as to reduce both voltages equally.
2. When the correction ratios of the inner current command value and the outer current command value are not equal FIG. 6 shows a conceptual diagram of the table. When the inner rotor driving voltage is 90% of the inverter driving voltage and the outer rotor driving voltage is 20%, a shortage of 10% occurs with respect to the power supply voltage. In this case, a table is prepared in which the outer rotor driving voltage is fixed to 20% and only the inner rotor voltage is corrected to 80%. It is necessary to prepare various tables for the ratio to be corrected according to the request from the system side such as a vehicle.

  FIG. 7 is a part of a control flowchart showing a second embodiment of the control method of the inverter device of the present invention. In the second embodiment of the present invention, the broken line part A in FIG. 3 is replaced by steps 110 to 115 shown in FIG.

  In the second embodiment of the present invention, the inner rotor and the outer rotor are determined based on the dq-axis current command value and the rotation speed of the inner rotor and the outer rotor, and predetermined motor parameters (coil resistance, dq-axis inductance, no-load magnetic flux). Each predicted dq-axis voltage value is derived (step 110), and a predicted composite dq-axis voltage value is calculated from the sum of the predicted dq-axis voltage values (step 111).

  Further, the predicted composite dq-axis voltage value is compared with the DC voltage value Vdc (step 112). If the predicted composite dq-axis voltage value does not exceed the DC voltage value Vdc, the dq-axis current value as set in the command value is set ( Step 113), if over, the dq axis voltage value is set so as to be within the range of the DC voltage (step 114), and the dq axis current value corresponding to the dq axis voltage value is calculated (step 115). Subsequently, the processing of steps 130 to 230 in FIG. 3 is performed. If it does not fall within the DC voltage range, limit the current command value by setting a limit.

  FIG. 8 is a control flowchart showing the third embodiment of the present invention. In the third embodiment, steps 210 to 217 shown in FIG. 8 are added to the control flowchart shown in FIG.

  After generating the command composite voltage in step 200, the composite voltage command value of each phase is compared with the DC voltage value Vdc (step 210). If the composite voltage command value of each phase is within the range of the DC voltage value Vdc, the inner The deviation between the target value and the command value of each phase voltage of the rotor and outer rotor is set to zero and fed back to step 216 (step 215), and PWM generation calculation is performed (step 230).

  If the composite voltage command value of each phase exceeds the DC voltage value Vdc, the correction ratio of the voltage command value of each phase is calculated (step 211), and the deviation between the target value of each phase voltage and the command value from the ratio Is calculated (step 212). Next, the deviation is separated into an inner rotor portion and an outer rotor portion (step 213). Since this deviation is a phase voltage, it is converted into a dq-axis voltage, and this is fed back to step 216 (step 214). A generation operation is performed (step 230). The feedback deviation of the dq-axis voltage is divided by the proportional gain to be the deviation of the dq-axis current (step 216), and is subtracted from the actual current command value so that it falls within the DC voltage range (step 217). .

  FIG. 9 is a control flowchart showing the fourth embodiment of the present invention. The fourth embodiment is the same procedure as the third embodiment, but the comparison with the DC voltage value Vdc is performed with the composite voltage command value of the dq axis (step 220).

  If the composite voltage command value of the dq axis is within the range of the DC voltage value Vdc, the deviation between the target value of each dq axis voltage of the inner rotor and the outer rotor and the command value is set to zero and fed back to step 224 (step 223). PWM generation calculation is performed (step 230). If the combined voltage command value of the dq axis exceeds the DC voltage value Vdc, the correction ratio of the command value of each dq axis voltage of the inner rotor and outer rotor is calculated (step 221), and the target of the dq axis voltage is calculated from the ratio. The deviation between the value and the command value is calculated, fed back to step 224 (step 222), and PWM generation calculation is performed (step 230).

  The deviation of the fed back dq axis voltage is divided by the proportional gain to be the deviation of the dq axis current (step 224), and is subtracted from the actual current command value so as to be within the DC voltage range (step 225). .

  In the first embodiment, as correction examples of the current command value, the correction ratios of the inner current command value and the outer current command value are equal, and the correction ratios of the inner current command value and the outer current command value are not equal. However, also in the second to fourth embodiments, the correction ratios of the inner current command value and the outer current command value are equalized, or one of the inner current command value and the outer current command value is fixed and the other is corrected. Needless to say, you can.

  In the above-described embodiment, the target value indicates a value set for a case that does not fall within the range of the DC voltage, and the command value is a value input from the outside to the control system, or Indicates a value that is calculated from the value and commands a controlled object.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall view of a hybrid drive unit to which a multi-axis multilayer motor as an example of a rotating electrical machine that is an object of a control method for an inverter device of the present invention is applied. It is a block diagram which shows an example of the inverter control apparatus which controls the inverter apparatus for driving a rotary electric machine. It is a control flowchart which shows the normal control method of an inverter control apparatus. It is a part of control flowchart which shows Example 1 of this invention. It is a figure which shows the example of the table which sets an electric current command value. It is a figure which shows the example of the table which sets an electric current command value. It is a part of control flowchart which shows Example 2 of this invention. It is a control flowchart which shows Example 3 of this invention. It is a control flowchart which shows Example 4 of this invention.

Explanation of symbols

21 inner PI control means 22 outer PI control means 23 dq axis → 6φ conversion means 24 dq axis → 3φ conversion means 25 6φ → dq axis conversion means 26 3φ → dq axis conversion means 27 phase current separation means 28 addition means 29 duty generation means 30 Gate signal generating means 31 Inverter device 32 Current sensor 33 Motor

Claims (8)

  In a control method of an inverter device for generating a current in which two different sine waves are combined to drive a rotating electric machine having two rotors inside and outside, the two rotors can be controlled within a controllable power supply voltage range. And setting a current command value to a predetermined value.   2. The method of controlling an inverter device according to claim 1, wherein the current command value is set so as to equally reduce the voltage applied to each rotor.   The method for controlling an inverter device according to claim 1 or 2, wherein a limit is set for the current command value by setting a limit when the maximum voltage value of a power supply is exceeded with respect to the current command value.   The relationship between the current command values for various conditions is prepared as a table in advance, and the current command value is set to a predetermined value by looking up the table. A control method for the inverter device according to claim 1.   The predicted value of the composite voltage is calculated from the current command value of the rotor, the number of rotations of the rotor and the motor parameter, and the current command value is calculated so that the predicted value does not exceed the voltage value of the power source. The control method of the inverter apparatus in any one of 1-3.   3. The method of controlling an inverter device according to claim 1, wherein when the maximum voltage value of the power source is exceeded, the excess amount is fed back and a difference from the current command value is obtained.   The composite voltage command value of each phase is compared with the voltage value of the power supply.If the composite voltage command value of each phase exceeds the voltage value of the power supply, the deviation between the target value of each phase voltage and the command value is calculated. 3. The method of controlling an inverter device according to claim 1, wherein the control unit calculates and feeds back and subtracts a deviation from an actual current command value.   The composite voltage command value of the dq axis is compared with the voltage value of the power source. If the composite voltage command value of the dq axis exceeds the voltage value of the power source, the deviation between the target value of the dq axis voltage and the command value is calculated. 3. The method of controlling an inverter device according to claim 1, wherein the control unit calculates and feeds back and subtracts a deviation from an actual current command value.

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