JP6447373B2 - Rotating machine control device - Google Patents

Description

  The present invention relates to a control device that controls energization of an AC rotating machine.

  2. Description of the Related Art Conventionally, there is known a rotating machine control device that limits a direct current in a rotating machine drive system in which a DC voltage of a DC power source is applied to an AC rotating machine using a power converter that converts an AC voltage into an AC voltage. For example, the control device disclosed in Patent Document 1 calculates the AC rotating machine voltage limit value from the deviation between the detected value of the DC current and the DC current limit value, and limits the DC current by limiting the voltage.

JP 2013-162561 A

  In an AC rotating machine drive system, a high-order component is superimposed on the zero-order component of the direct current, and the peak value of the high-order component becomes the peak value of the direct current. In the prior art of Patent Document 1, the direct current is reduced as a whole by limiting the voltage so that the peak value of the direct current is less than or equal to the limit value. For this reason, the average current decreases with a decrease in the peak value, and as a result, the output torque of the rotating machine decreases. Then, for example, when applied to a main motor of a hybrid vehicle, drivability is reduced.

  The present invention was created in view of the above points, and an object thereof is to provide a control device for a rotating machine that appropriately limits a direct current without reducing the torque of the rotating machine. .

The present invention is used in a rotating machine drive system that converts a DC voltage of a DC power source into an AC voltage by a power converter and applies the AC voltage to the rotating machine, and controls the rotating machine that controls the energization of the rotating machine by operating the power converter. It is an invention related to the apparatus.
The rotating machine control device includes a voltage amplitude calculation unit, a direct current limit determination unit, a voltage pulse setting unit, and a gate signal generation unit.

The voltage amplitude calculation unit calculates a voltage amplitude command based on at least the torque command of the rotating machine.
The direct current limit determination unit determines whether or not the peak value of the direct current flowing between the direct current power source and the power converter is equal to or less than a predetermined direct current limit value.

The voltage pulse setting unit sets a voltage pulse having a pulse number that is the number of ON / OFF times per electrical cycle of each phase based on the voltage amplitude command so that the peak value of the DC current is less than or equal to the DC current limit value. To do.
The gate signal generation unit generates a gate signal for operating the power converter based on the voltage pulse set by the voltage pulse setting unit.

For example, the voltage pulse setting unit increases the number of voltage pulses as the power supply voltage input to the power converter is higher. Or a voltage pulse setting part changes the pulse number of a voltage pulse according to one or more values among the torque of a rotary machine, rotation speed, or the power supply voltage input into a power converter.
Then, the voltage pulse setting unit sets the voltage pulse by increasing the number of pulses until the peak value of the direct current becomes equal to or less than the limit value. At this time, the average direct current does not change.
Thereby, the control apparatus of the rotary machine of this invention can restrict | limit a direct current appropriately, without reducing the torque of a rotary machine. Therefore, for example, when applied to a main motor of a hybrid vehicle, a decrease in drivability can be avoided.

  By the way, the number of voltage pulses has a limit depending on the relationship with the switching loss and voltage limit of the power converter. In other words, there may be no voltage pulse that can increase the number of pulses while maintaining the voltage amplitude command calculated by the voltage amplitude calculation unit. Therefore, when the peak value of the DC current exceeds the limit value, the peak value of the DC current cannot be lowered sufficiently only by adjusting the number of pulses by the voltage pulse setting unit, and the voltage amplitude command must be lowered. It is assumed that there is not.

  Therefore, it is preferable that the control device for a rotating machine of the present invention further includes a voltage phase calculating unit that calculates a voltage phase so that the torque of the rotating machine follows the command torque and outputs the voltage phase to the gate signal generating unit. Here, the torque of the rotating machine may be estimated based on the dq-axis current, or directly detected by a torque sensor. Thereby, even when the voltage amplitude command has to be lowered, the output torque of the rotating machine can be supplemented by operating the voltage phase, and the required torque can be appropriately secured.

The control block diagram of the control apparatus of the rotary machine by 1st Embodiment of this invention. The figure explaining the rate-of-change restriction | limiting of a voltage amplitude command. The figure explaining the definition of the pulse number n in a line voltage pulse and each phase voltage pulse. The figure explaining the relationship between the pulse number of a voltage pulse and the magnitude | size of a high-order component. The figure explaining the voltage pulse production | generation of (a) pulse number n = 3 and (b) n = 9 in sine wave PWM control. The characteristic diagram which shows the relationship of (a) number of rotations-number of pulses, (b) power supply voltage-number of pulses. The current wave form diagram explaining the direct current limit by embodiment of this invention. The dq axis | shaft coordinate diagram explaining adjustment of a voltage phase. The characteristic diagram which shows the relationship of (a) voltage phase-direct current, (b) voltage phase-torque. The flowchart of the voltage pulse setting by 1st Embodiment of this invention. The control block diagram of the control apparatus of the rotary machine by 2nd Embodiment of this invention. The figure explaining the calculation timing of the voltage phase with respect to the period of a high-order component. The flowchart of the voltage pulse setting by 2nd Embodiment of this invention. The control block diagram of the control apparatus of the rotary machine by 3rd Embodiment of this invention. The figure explaining the voltage pulse production | generation of (a) pulse number n = 3 and (b) n = 9 in overmodulation PWM control. The current wave form diagram explaining the direct current limitation by a prior art.

Hereinafter, a control device for a rotating machine according to an embodiment of the present invention will be described with reference to the drawings. In the plurality of embodiments, substantially the same configuration is denoted by the same reference numeral, and description thereof is omitted.
This control device for a rotating machine is applied as a control device for a main motor of a hybrid vehicle or an electric vehicle, for example. In the following description of the embodiment, the part corresponding to the “rotor” in the claims is referred to as “motor”. The “present embodiment” includes the first to third embodiments.

(First embodiment)
A control device for a rotating machine according to a first embodiment will be described with reference to FIGS.
A motor drive system 90 shown in FIG. 1 includes a battery 50 as a “DC power supply”, a DC current sensor 55, an inverter 60 as a “power converter”, a motor 80 driven by AC power, and the like. A motor control device 101 applied to the motor drive system 90 controls the energization of the motor 80 by operating the inverter 60.

The motor 80 is, for example, a permanent magnet type synchronous three-phase AC motor, and is typically a motor generator capable of power running and regenerative operation.
The power supply voltage Vdc is input from the battery 50 to the inverter 60. In the inverter 60, a plurality of switching elements of upper and lower arms are bridge-connected, and a DC voltage is converted into an AC voltage by a switching operation of the switching elements and applied to the winding of the motor 80. Since the configuration of the inverter 60 is well known, illustration and detailed description thereof are omitted.

On the power line connected from the inverter 60 to the motor 80, current sensors 71 and 72 for detecting a phase current are provided.
The rotation angle sensor 85 detects the rotation angle of the motor 80 and outputs it as an electrical angle θe. The electrical angle θe is used in vector control coordinate conversion calculation by the motor control device 101. Further, the electrical angle θe is time-differentiated by the differentiator 86, and the electrical angular velocity ω [deg / s] is calculated. Since the electrical angular velocity ω is converted to the rotational speed N [rpm] by multiplying by a proportionality constant, “the rotational speed converted from the electrical angular velocity ω” is omitted in this specification and referred to as “the rotational speed ω”.

DC current sensor 55 detects a DC current Idc that flows between battery 50 and inverter 60.
Here, as disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2013-162561), when the direct current Idc exceeds a predetermined limit value, heat generation on the power supply path, destruction of electronic components, deterioration of the battery, etc. May cause problems. Therefore, in the prior art of Patent Document 1, the AC rotating machine voltage limit value is calculated from the deviation between the detected value of the DC current and the DC current limit value, and the DC current is limited by limiting the voltage.

DC current limitation according to the prior art will be described with reference to FIG. Here, it is assumed that the motor to be controlled is a three-phase AC motor. An electrical cycle Te shown on the horizontal axis in FIG. 16 corresponds to the cycle of the phase current primary component.
In a three-phase AC motor drive system, a higher-order component such as a sixth-order component having a frequency six times that of the first-order phase current component is superimposed on the zero-order component of the DC current. That is, the direct current includes a high-order component such as a sixth-order component that periodically fluctuates in addition to a zero-order component that is constant over several electrical cycles. The peak value of this higher-order component becomes the DC current peak value Idc_p.

  In the prior art of Patent Document 1, the direct current is reduced as a whole by limiting the voltage so that the peak value Idc_p of the direct current is equal to or less than the limit value Idc_lim. Therefore, the peak value Idc_p decreases and the average current Idc_avr also decreases, and as a result, the motor output torque decreases. Then, for example, when applied to a main motor of a hybrid vehicle, drivability is reduced.

  With respect to this problem, the present embodiment aims to appropriately reduce the peak value Idc_p of the direct current without reducing the output torque of the motor 80. Therefore, since the peak value Idc_p of the direct current is a peak value of the high-order component, it is noted that if the amplitude of the high-order component is suppressed, the peak value Idc_p can be lowered while maintaining the average current Idc_avr of the direct current Idc. . The higher order component included in the direct current Idc is related to the higher order component superimposed on the phase current of the motor 80. Therefore, by reducing the high-order component of the voltage applied to the motor 80, it is possible to reduce the high-order component included in the direct current Idc.

Then, the specific structure of the motor control apparatus 101 for solving the said subject is demonstrated. The motor control device 101 is configured to generate a voltage pulse while limiting the DC current Idc, as a voltage amplitude calculation unit 13, a DC current limit determination unit 15, a voltage pulse setting unit 16, a power supply voltage detection unit 17, and a gate signal generation. A portion 18 is provided.
Moreover, the motor control apparatus 101 of 1st Embodiment is provided with the dq conversion part 34, the torque estimation part 35, the subtractor 36, and the controller 37 as a structure peculiar to torque feedback control.

The voltage amplitude calculator 13 calculates a voltage amplitude command Vamp based on the rotational speed ω of the motor 80 and the torque command T ^* input from the vehicle control device or the like.
Here, FIG. 2 is referred to regarding the change rate limitation of the voltage amplitude command Vamp at successive control timings. The horizontal axis in FIG. 2 indicates control timings t0 to t3 that are continuous in the control cycle ΔTc, and the vertical axis indicates the value of the voltage amplitude command Vamp calculated at each control timing.

From the viewpoint of preventing the direct current Idc from exceeding the limit value Idc_lim, it is not preferable to increase the voltage amplitude command Vamp rapidly. Therefore, the voltage amplitude calculation unit 13 sets an upper limit for the rate of change when the voltage amplitude command Vamp is increased. The upper limit change rate is preferably set to be equal to or less than the change rate of the torque command T ^* input at the same timing.

The voltage amplitude command change rate Rv1 from the previous timing t0 at the control timing t1 is expressed by Expression (1.1). Similarly, the change rates Rv2 and Rv3 from the previous timings t1 and t2 at the control timings t2 and t3 are expressed by equations (1.2) and (1.3).
Rv1 = (Vamp (t1) −Vamp (t0)) / ΔTc (1.1)
Rv2 = (Vamp (t2) −Vamp (t1)) / ΔTc (1.2)
Rv3 = (Vamp (t3) −Vamp (t2)) / ΔTc (1.3)

The change rate Rv1 is smaller than the upper limit change rate indicated by a broken line, and the change rate Rv2 is equivalent to the upper limit change rate. Therefore, the calculated voltage amplitude commands Vamp (t1) and Vamp (t2) are output as they are. On the other hand, since the change rate Rv3 exceeds the upper limit change rate, the calculated voltage amplitude command Vamp (t3) is output after being limited to the upper limit value Vamp (t3) _lim.
When the voltage amplitude command Vamp decreases, it is not necessary to limit the rate of change.

The DC current limit determination unit 15 determines whether or not the DC current peak value Idc_p detected by the DC current sensor 55 is equal to or less than the limit value Idc_lim (see FIG. 7).
The voltage pulse setting unit 16 sets a voltage pulse based on the voltage amplitude command Vamp. The number n of voltage pulses is defined by the number of ON / OFF times per electrical cycle of each phase.

  FIG. 3 shows an example of “number of pulses n = 7” of the voltage pulse between the U-V phase line and the pulse of the switching element (“SW element” in the figure) of the U-phase and V-phase corresponding thereto. Show. In each phase pulse, there are 7 rising edges (ON) and 7 falling edges (OFF) in one electrical cycle, that is, in the range of electrical angle 360 [deg]. When one reciprocation of ON and OFF is counted as one pulse, the number of pulses is seven. Further, in the line voltage pulse, the electrical (1/2) period, that is, the number of ON / OFF in the range of the electrical angle of 180 [deg] corresponds to the number of pulses. Thus, each phase pulse and the line voltage pulse correspond to each other.

The voltage pulse setting unit 16 acquires the determination result by the direct current limit determination unit 15, the rotation speed ω of the motor 80, and the power supply voltage Vdc detected by the power supply voltage detection unit 17.
When the DC current peak value Idc_p exceeds the limit value Idc_lim, the voltage pulse setting unit 16 changes the number of pulses and sets the voltage pulse so that the DC current peak value Idc_p is equal to or less than the limit value Idc_lim.

Refer to FIG. 4 for the relationship between the number of voltage pulses and the magnitude of higher order components. The number of pulses is smaller on the left side of FIG. 4, and the number of pulses is larger on the right side. The first stage shows when the voltage amplitude command Vamp is the reference voltage V ₀ , and the second stage shows when the voltage amplitude command Vamp is 0.9 times the reference voltage V ₀ . The smaller the voltage amplitude command Vamp, the smaller the width (ON period) of each pulse.

When considered on the basis of PWM modulation, the voltage waveform applied to the motor 80 becomes closer to a sine wave as the number of pulses increases, and the amplitude ratio of superposed higher-order components becomes smaller. Further, the smaller the number of pulses, the closer to a rectangular wave, and the higher the higher-order component amplitude ratio becomes. Thus, if the number of pulses is increased, the higher order component of the voltage applied to the motor 80 can be reduced, and as a result, the higher order component included in the DC current Idc can be reduced.
However, if the number of pulses is increased more than necessary, switching loss will increase. Therefore, the voltage pulse setting unit 16 increases the number of pulses until the DC current peak value Idc_p becomes equal to or less than the limit value Idc_lim, and does not increase the number of pulses beyond that.

  A method for generating a voltage pulse based on PWM modulation will be described with reference to FIG. FIG. 5 shows an example of (a) pulse number n = 3 and (b) pulse number n = 9 in sine wave PWM control. The voltage pulse is generated by comparing the voltage command with the carrier (triangular wave). Therefore, the number of pulses n can be adjusted by changing the number of carriers per electrical cycle.

  As shown in FIGS. 5A and 5B, when the pulse number n is set to an odd number and the peak or valley timing of the carrier is synchronized with the electrical angle θe at which the voltage command is maximum and minimum, the voltage Pulses can be generated symmetrically. Furthermore, as shown in FIG. 5 (b), by setting the number of pulses n to a multiple of 3, three-phase symmetry can be ensured.

Further, the voltage pulse setting unit 16 may change the number n of voltage pulses in accordance with at least one of the motor rotation speed ω and the power supply voltage Vdc that are the operating conditions of the motor 80.
The smaller the motor rotation speed ω, that is, the lower the rotation speed, the longer one electrical cycle and the greater the influence of higher-order components. Therefore, as shown in FIG. 6A, it is preferable to increase the pulse number n as the motor rotational speed ω is smaller.

Further, as the power supply voltage Vdc is higher, the value of the higher-order component of the direct current Idc is increased, and the margin to the limit value Idc_lim is reduced. Therefore, as shown in FIG. 6B, it is preferable to increase the number of pulses n as the power supply voltage Vdc is higher.
Note that the characteristic lines in FIGS. 6A and 6B indicate only the direction of correlation, and specific characteristic profiles such as linear and inverse proportional forms are not limited to the illustrated example.

The gate signal generation unit 18 acquires the voltage pulse set by the voltage pulse setting unit 16, the voltage phase Vθ calculated by the controller 37, and the electrical angle θe from the rotation angle sensor 85.
The gate signal generation unit 18 generates a gate signal for operating the inverter 60 by PWM control or the like based on the voltage amplitude command Vamp of the voltage pulse and the voltage phase Vθ. At this time, the gate signal generation unit 18 converts the voltage command into a three-phase command value by using the electrical angle θe. The gate signal is composed of 6 signals UH, UL, VH, VL, WH and WL corresponding to the switching elements of the upper and lower arms of each phase. Each switching element performs ON / OFF operation according to the gate signal.

Based on this gate signal, the switching element of the inverter 60 performs a switching operation to convert DC power into three-phase AC power. Then, when the inverter 60 applies desired three-phase AC voltages Vu, Vv, and Vw to the motor 80, the drive of the motor 80 is controlled so as to output a torque corresponding to the torque command T ^* .

  FIG. 7 is referred to for the DC current limitation of the present embodiment realized by the configuration described so far. FIG. 7 corresponds to FIG. 16 of the prior art. As shown in FIG. 7A, when the number n of voltage pulses is relatively small, the peak value Idc_p exceeds the limit value Idc_lim due to the sixth-order component included in the DC current Idc.

Therefore, the voltage pulse setting unit 16 increases the number of pulses n until the DC current peak value Idc_p becomes equal to or less than the limit value Idc_lim, as shown in FIG. At this time, the average current Idc_avr of the direct current does not change.
Thereby, as the effect [1] of the first embodiment, the direct current Idc can be appropriately limited without reducing the torque of the motor 80. Therefore, when applied to a main motor of a hybrid vehicle, a decrease in drivability can be avoided.

Next, a configuration unique to torque feedback control will be described.
The dq conversion unit 34 acquires the phase current detection value from the current sensors 71 and 72. In this embodiment, detected values of the V-phase current Iv and the W-phase current Iw are input from the current sensors 71 and 72 provided in the V-phase and the W-phase, and the remaining U-phase current Iu is estimated based on Kirchhoff's law. doing. In other embodiments, any two-phase current may be detected, and a three-phase current may be detected. Or you may employ | adopt the technique which estimates the other two-phase electric current based on the electric current detection value of one phase.
The dq converter 34 dq converts the three-phase current detection values Iu, Iv, Iw into dq-axis currents Id, Iq using the electrical angle θe.

Torque estimating unit 35, based on the dq-axis current Id, Iq and a circuit constant, calculates the estimated torque T_est using equation (2), is fed back to the torque command T ^*.
T_est = pm × {Iq × φα + (Ld−Lq) × Id × Iq} (2)
However,
pm: number of pole pairs of motor φα: armature interlinkage magnetic flux of permanent magnet Ld, Lq: d-axis inductance, q-axis inductance

The subtractor 36 subtracts the estimated torque T_est calculated by the torque estimation unit 35 from the torque command T ^* to calculate a torque deviation.
The controller 37 as the “voltage phase calculator” calculates the voltage phase Vθ by PI control calculation or the like so that the torque deviation converges to zero. Thus, in the first embodiment, the voltage phase Vθ calculated so that the output torque of the motor 80 matches the torque command T ^* is input to the gate signal generation unit 18.

By the way, the number n of voltage pulses has a limit depending on the switching loss of the inverter 60 and the voltage limit. In other words, there may be no voltage pulse that can increase the number of pulses n while maintaining the voltage amplitude command Vamp calculated by the voltage amplitude calculation unit 13.
Therefore, when the peak value Idc_p of the direct current exceeds the limit value Idc_lim, the peak value Idc_p of the direct current cannot be lowered sufficiently only by adjusting the number of pulses n by the voltage pulse setting unit 16, and the voltage amplitude command A case where Vamp must be reduced is assumed.

In such a case, the motor control device 101 according to the first embodiment is characterized in that the output torque of the motor 80 that is insufficient with respect to the required torque is compensated by the operation of the voltage phase Vθ. This operation will be described with reference to FIGS.
In the dq axis current coordinates shown in FIG. 8, the equal torque line based on the above equation (2) is defined as a function of the dq axis currents Id and Iq. If the voltage command before the phase operation is V ^* ₁ , and the voltage command after the phase operation is V ^* ₂ , the current command vectors I ^* ₁ and I ^* ₂ corresponding to the voltage command vectors V ^* ₁ and V ^* ₂ The amplitudes Iamp ₁ and Iamp ₂ are represented by concentric ellipses.

The current command vector I ^* ₂ is advanced in phase with respect to the current command vector I ^* ₁ . Further, the end points of the current command vectors I ^* ₁ and I ^* ₂ are located on the equal torque line.
Speaking of voltage command vectors, by advancing the voltage phase Vθ from the voltage command vector V ^* ₁ to V ^* ₂ , the voltage torque command is reduced from Vamp ₁ to Vamp ₂ while maintaining the output torque equal. Can do.

FIG. 9 shows the relationship between the voltage phase Vθ, (a) DC current Idc, and (b) torque T. The voltage amplitude command of “pulse 1” before phase operation is Vamp ₁ and the voltage phase is θ ₁ . The voltage amplitude command of “pulse 2” after the phase operation is Vamp ₂ (<Vamp ₁ ), and the voltage phase is θ ₂ (> θ ₁ ).

9 (a), the DC current Idc ₁ Pulse 1, the DC current Idc ₂ by pulse 2, and the relationship of the DC current limit Idc_lim is represented by the formula (3.1).
Idc ₂ ≦ Idc_lim <Idc ₁ (3.1)
In FIG. 9B, the relationship between the output torque T _{1 due} to the pulse ₁ and the output torque T ₂ due to the pulse 2 is expressed by the equation (3.2).
T ₂ = T ₁ (3.2)
Further, from FIG. 9A, the advance angle limit value θ _MAX of the voltage phase Vθ is determined based on the DC current limit value Idc_lim.

Thus, in the first embodiment, the voltage phase Vθ is calculated so that the output torque of the motor 80 follows the torque command T ^* . As a result, as an effect [2] of the first embodiment, even when the voltage amplitude command Vamp has to be lowered, the output torque of the motor 80 can be supplemented by operating the voltage phase Vθ, and the required torque can be appropriately secured. it can.

Next, a voltage pulse setting routine by the motor control device 101 according to the first embodiment will be described with reference to the flowchart of FIG. This routine is repeatedly executed, for example, every electrical cycle. In the description of the flowchart below, the symbol “S” means a step.
In S01, the voltage pulse setting unit 16 initializes the voltage pulse based on the voltage amplitude command Vamp calculated by the voltage amplitude calculation unit 13. In S02, the direct current sensor 55 detects the direct current Idc, and the direct current limit determination unit 15 acquires the detected value.

  In S03, the direct current limit determination unit 15 determines whether or not the peak value Idc_p of the direct current is equal to or less than the limit value Idc_lim. When it is determined that the peak value Idc_p of the direct current exceeds the limit value Idc_lim (S03: NO), the voltage pulse setting unit 16 resets the voltage pulse with the number of pulses n increased (S04). Then, the direct current sensor 55 detects the direct current Idc again (S02).

When the peak value Idc_p of the direct current is equal to or less than the limit value Idc_lim (S03: YES), next, in S09, it is determined whether the motor 80 can output a torque greater than the required torque. In the configuration of FIG. 1, the estimated torque T_est calculated by the torque estimating unit 35 is compared with the torque command T ^* . If the motor 80 can output a torque greater than the required torque (S09: YES), the voltage pulse set at that time is adopted. On the other hand, when the output torque of the motor 80 is less than the required torque (S09: NO), the controller 37 operates the voltage phase Vθ so as to satisfy the required torque (see FIGS. 8 and 9).

(Second Embodiment)
A control device for a rotating machine according to a second embodiment will be described with reference to FIGS.
The motor control apparatus 102 of the second embodiment further includes a high-order component extraction unit 25, a subtractor 26, a controller 27, and a subtractor 28 in addition to the configuration of the first embodiment.
The high-order component extraction unit 25 extracts a high-order component Idc_h superimposed on the zero-order component of the direct current using a high-pass filter, a band-pass filter, or the like. As shown in FIG. 7, the main high-order component in the system for driving the three-phase AC motor 80 is a sixth-order component having a frequency six times that of the phase current primary component. In addition to the 6th order component, higher order components such as the 12th order and the 18th order are also included, but it is sufficient to extract the 6th order component for the purpose of reducing the peak value Idc_p.

  The subtractor 26 calculates the difference between the extracted higher-order component Idc_h and the zero point of the DC current sensor 55. The controller 27 calculates the voltage phase correction amount Vθ_comp according to the difference between the high-order component Idc_h and the zero point. When the DC current limit determination unit 15 determines that the DC current peak value Idc_p exceeds the DC current limit value Idc_lim, the voltage phase correction amount Vθ_comp is output to the subtractor 28.

The subtracter 28 subtracts the voltage phase correction amount Vθ_comp from the voltage phase Vθ calculated by the controller 37 and outputs the result to the gate signal generation unit 18. The operation of the voltage phase Vθ by the subtraction of the correction amount Vθ_comp is a period of 1 / k (k is a natural number) with respect to a period of a sixth-order component that is a higher-order component, that is, a period of 1/6 of one electrical period. Is executed.
FIG. 12 shows an example in which the voltage phase Vθ is manipulated at a calculation timing obtained by dividing one period of the higher-order component into four. In this way, by operating the voltage phase Vθ with a period of 1 / k with respect to the period of the high-order component, the voltage phase Vθ can be operated in a direction that appropriately cancels the high-order component.

In the flowchart shown in FIG. 13, when it is determined that the peak value Idc_p of the direct current exceeds the limit value Idc_lim (S03: NO) with respect to FIG. 10, instead of resetting the voltage pulse (S04), S05 The difference is that S08 is executed.
In S05, the high-order component extraction unit 25 extracts the high-order component Idc_h included in the direct current Idc using a high-pass filter. In S06, the subtractor 26 calculates the difference between the extracted higher-order component Idc_h and the zero point of the DC current sensor 55.

In S07, the controller 27 calculates the voltage phase correction amount Vθ_comp according to the difference between the higher-order component Idc_h and the zero point. In S08, the subtractor 28 subtracts the voltage phase correction amount Vθ_comp from the voltage phase Vθ.
As described above, in the second embodiment, in addition to the effects of the first embodiment, when the peak value Idc_p of the direct current exceeds the limit value Idc_lim, the period of 1 / k with respect to the period of the higher-order component. The voltage phase Vθ is manipulated by subtracting the voltage phase correction amount Vθ_comp. Thereby, the high-order component contained in direct current Idc can be reduced appropriately, and direct current Idc can be restricted.

(Third embodiment)
A control device for a rotating machine according to a third embodiment will be described with reference to FIG.
The motor control device 103 of the third embodiment is a current feedback control type control device. As a configuration different from that of the first embodiment, a current command calculation unit 31, a subtractor 32, a controller 33, and a voltage amplitude phase calculation unit 14 are provided. On the other hand, the torque estimation unit 35 and the subtractor 36 of the first embodiment are not provided.

  In the first embodiment, the voltage amplitude calculation unit 13 calculates the voltage amplitude command Vamp, and the controller 37 as the “voltage phase calculation unit” calculates the voltage phase Vθ, whereas the voltage of the third embodiment The amplitude phase calculation unit 14 calculates both the voltage amplitude command Vamp and the voltage phase Vθ. The voltage amplitude phase calculation unit 14 of the third embodiment corresponds to a “voltage amplitude calculation unit” recited in the claims.

The current command calculation unit 31 calculates dq-axis current command values Id ^* and Iq ^* using a map or a mathematical formula based on the torque command T ^* acquired from the vehicle control device or the like.
The subtractor 32 subtracts the dq axis currents Id and Iq fed back from the dq converter 34 from the dq axis current command values Id ^* and Iq ^* to calculate a dq axis current deviation.
The controller 33 calculates the dq-axis voltage command values Vd ^* and Vq ^* by PI control calculation or the like so that the dq-axis current deviation converges to zero.

The voltage amplitude phase calculation unit 14 calculates the amplitude Vamp and the phase Vθ of the voltage command vector based on the dq axis voltage command values Vd ^* and Vq ^* . When the voltage phase Vθ is defined in the counterclockwise direction with the + Vd axis as a reference, the voltage phase Vθ [deg] is calculated by the following equations (4.1) to (4.3) according to the sign of Vd ^* and Vq ^*. Is done.
[Vd ^* > 0, Vq ^* ≧ 0] Vθ = arctan (Vq ^* / Vd ^* ) (4.1)
[Vd ^* <0] Vθ = arctan (Vq ^* / Vd ^* ) + 180 (4.2)
[Vd ^* > 0, Vq ^* <0] Vθ = arctan (Vq ^* / Vd ^* ) + 360
... (4.3)

The voltage amplitude command Vamp is output to the voltage pulse setting unit 16, and the voltage phase Vθ is output to the gate signal generation unit 18. The subsequent steps are the same as in the first embodiment.
The setting of the voltage pulse according to the third embodiment is the same as that of the first embodiment except that the voltage phase Vθ is manipulated so as to satisfy the required torque. That is, the steps from S01 to S04 are executed in FIG. Therefore, the effect [1] of the first embodiment is exhibited in common.

(Other embodiments)
(A) As a voltage pulse generation method by the voltage pulse setting unit 16, FIG. 5 shows a method based on a comparison between a voltage command and a carrier in sine wave PWM control. This method is applicable not only to the sine wave PWM control but also to the overmodulation PWM control and the rectangular wave control shown in FIG.
In addition to the voltage pulse generation method based on carrier comparison, a plurality of types of pulse patterns that prescribe the edge timing and pulse width (ON period) of each pulse are stored in advance, and the optimum pulse pattern according to the operating conditions of the motor 80 is stored. You may employ | adopt methods, such as selecting.

(A) As described above, the voltage pulse setting unit 16 sets the number n of voltage pulses in accordance with one or more values of the torque T, the rotational speed ω, or the power supply voltage Vdc of the motor 80. The information on the torque T, the rotational speed ω, and the power supply voltage Vdc is not limited to the information acquired by the configuration exemplified in the above embodiment, and alternative values acquired as follows may be used.
[Torque T]
Instead of the estimated torque calculated from the dq axis current, the motor torque may be directly detected by a torque sensor. Further, an approximate torque may be estimated from the current amplitude.

[Rotation speed ω]
In a hybrid vehicle, the rotation speed of each part to which the rotation of the motor 80 is transmitted, such as the rotation speed of the engine and the axle (wheel or drive shaft), is obtained and converted into the motor rotation speed ω using the gear ratio. Good.
[Power supply voltage Vdc]
You may convert from SOC (charge rate) of the battery 50. FIG. Further, since the discharge capacity of the battery 50 is “total amount of current that can be output”, the current power supply voltage Vdc can be estimated based on the integrated value of the input / output DC current Idc.

(C) The present invention may be applied to a system including a DCDC converter between the battery 50 and the inverter 60. For example, when a boost converter is used, the boost voltage input to the inverter 60 may be regarded as a “power supply voltage”.
(D) The rotating machine to be controlled in the present invention is not limited to a three-phase rotating machine, and may be a four-phase or more multi-phase rotating machine. When applied to a p-phase rotating machine, the number of pulses n is preferably a multiple of p in order to ensure symmetry between phases.

(E) The present invention may be applied not only to a rotating machine used as a main motor of a hybrid vehicle or an electric vehicle, but also to a rotating machine used in an auxiliary motor for a vehicle, an elevator other than a vehicle, a general machine, or the like. Good.
As mentioned above, this invention is not limited to the said embodiment at all, In the range which does not deviate from the meaning of invention, it can implement with a various form.

101, 102, 103 ... motor control device (control device for rotating machine),
13, 14... Voltage amplitude calculation unit,
15 ... DC current limit determination unit,
16 ... Voltage pulse setting unit,
18: Gate signal generator,
37 ... Controller (voltage phase calculation unit),
50 ... Battery (DC power supply),
60: Inverter (power converter),
80 ... motor (rotary machine),
90: Motor drive system (rotary machine drive system).

Claims (12)

Used in a rotating machine drive system (90) that converts a DC voltage of a DC power supply (50) into an AC voltage by a power converter (60) and applies it to the rotating machine (80), and operates the power converter to rotate the rotation. A control device for a rotating machine that controls energization of the machine,
A voltage amplitude calculator (13, 14) for calculating a voltage amplitude command based on at least the torque command of the rotating machine;
A direct current limit determination unit (15) for determining whether or not a peak value of a direct current flowing between the direct current power source and the power converter is equal to or less than a predetermined direct current limit value;
Voltage pulse setting for setting a voltage pulse having a pulse number that is the number of ON / OFF times per electrical cycle of each phase based on the voltage amplitude command so that the peak value of the direct current is equal to or less than the direct current limit value. Part (16),
A gate signal generator (18) for generating a gate signal for operating the power converter based on the voltage pulse set by the voltage pulse setting unit;
Equipped with a,
Wherein the voltage pulse setting unit, the control device of the rotary machine, wherein Rukoto increasing the number of pulses of the power the higher the power supply voltage input to the converter the voltage pulse. Wherein the voltage pulse setting unit, a control device for a rotary machine according to claim 1, characterized in that increasing the number of pulses of the rotating machine as the voltage pulse is smaller rotational speed of the. Used in a rotating machine drive system (90) that converts a DC voltage of a DC power supply (50) into an AC voltage by a power converter (60) and applies it to the rotating machine (80), and operates the power converter to rotate the rotation. A control device for a rotating machine that controls energization of the machine,
A voltage amplitude calculator (13, 14) for calculating a voltage amplitude command based on at least the torque command of the rotating machine;
A direct current limit determination unit (15) for determining whether or not a peak value of a direct current flowing between the direct current power source and the power converter is equal to or less than a predetermined direct current limit value;
Voltage pulse setting for setting a voltage pulse having a pulse number that is the number of ON / OFF times per electrical cycle of each phase based on the voltage amplitude command so that the peak value of the direct current is equal to or less than the direct current limit value. Part (16),
A gate signal generator (18) for generating a gate signal for operating the power converter based on the voltage pulse set by the voltage pulse setting unit;
A voltage phase calculation unit (37) that calculates a voltage phase (Vθ) so that the torque of the rotating machine follows a torque command, and outputs the voltage phase (Vθ) to the gate signal generation unit;
Equipped with a,
Advance-angle limit value of the voltage phase, the control device of the rotary machine, wherein Rukoto be determined based on the DC current limit value. Used in a rotating machine drive system (90) that converts a DC voltage of a DC power supply (50) into an AC voltage by a power converter (60) and applies it to the rotating machine (80), and operates the power converter to rotate the rotation. A control device for a rotating machine that controls energization of the machine,
A voltage amplitude calculator (13, 14) for calculating a voltage amplitude command based on at least the torque command of the rotating machine;
A direct current limit determination unit (15) for determining whether or not a peak value of a direct current flowing between the direct current power source and the power converter is equal to or less than a predetermined direct current limit value;
Voltage pulse setting for setting a voltage pulse having a pulse number that is the number of ON / OFF times per electrical cycle of each phase based on the voltage amplitude command so that the peak value of the direct current is equal to or less than the direct current limit value. Part (16),
A gate signal generator (18) for generating a gate signal for operating the power converter based on the voltage pulse set by the voltage pulse setting unit;
Equipped with a,
It said voltage amplitude calculating unit, the voltage rotary machine control apparatus which is characterized that you set the upper limit on the rate of change when increasing the amplitude command. The control apparatus for a rotating machine according to claim 4 , wherein the upper limit change rate of the voltage amplitude command is set to be equal to or less than the change rate of the torque command. The voltage pulse setting unit may change the pulse number of the voltage pulse according to one or more values of torque, rotation speed, or power supply voltage input to the power converter. The control device for a rotating machine according to any one of claims 3 to 5, characterized in that: The said voltage pulse setting part increases the pulse number of the said voltage pulse, so that the rotation speed of the said rotary machine is small, The control apparatus of the rotary machine of Claim 6 characterized by the above-mentioned. The said voltage pulse setting part increases the pulse number of the said voltage pulse, so that the said power supply voltage is high, The control apparatus of the rotary machine of Claim 6 or 7 characterized by the above-mentioned. The control device for a rotating machine according to any one of claims 1 to 8 , wherein the voltage pulse setting unit sets the number of voltage pulses to an odd number. A higher-order component extraction unit (25) for analyzing higher-order components included in the direct current;
When the DC current limit determination unit determines that the peak value of the DC current exceeds the DC current limit value,
The control apparatus for a rotating machine according to any one of claims 1 to 9, wherein the high-order component extraction unit manipulates a voltage phase according to the extracted high-order component.   11. The control device for a rotating machine according to claim 10, wherein the high-order component extraction unit manipulates the voltage phase at a cycle of 1 / k (k is a natural number) with respect to the cycle of the high-order component. The rotating machine is a three-phase AC rotating machine,
The control apparatus for a rotating machine according to claim 10 or 11, wherein the higher-order component is a sixth-order component.

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