JP2012165607A - Control device for rotary machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which reducing a high frequency voltage signal lowers the accuracy of estimating an electrical angle.SOLUTION: A high frequency voltage signal setting section 50 sets high frequency voltage command signals. An operating signal generation section 32 sets inverter operating signals g*# (*=u,v,w; #=n,p) accordingly. Meanwhile, a high pass filter 58 extracts high frequency current signals idh and iqh from currents id and iq flowing through a motor generator. An outer product computation section 60 calculates an outer product value of actually superimposed high frequency voltage command signals and the high frequency current signals. A rotational angle θ is manipulated such that a difference between the outer product value and a desired value becomes zero. The actually superimposed high frequency voltage signals are the high frequency voltage command signals compensated by error voltages calculated by a dead time error voltage calculation section 52.

Description

  The present invention provides a switching element for selectively connecting a terminal of a rotating machine having saliency to each of a positive electrode and a negative electrode of a DC voltage source and a DC / AC converter circuit including a diode connected in reverse parallel to the switching element. In controlling the control amount of the rotating machine, superimposing means for superimposing a high-frequency voltage signal having a frequency higher than the electrical angular frequency of the rotating machine on the output voltage of the DC-AC converter circuit, and the superimposed high-frequency voltage signal And a estimator for estimating a rotation angle of the rotating machine based on a detected value of a high-frequency current signal flowing through the rotating machine.

  As this type of control device, for example, as shown in Patent Document 1 below, when a high-frequency voltage signal that vibrates in the positive and negative directions of the estimated d-axis of a three-phase motor is applied, the high-frequency that actually propagates to the motor Some have also been proposed that estimate the electrical angle of an electric motor based on a current signal.

Japanese Patent No. 3312472

  By the way, since the frequency of the high-frequency voltage signal is usually within an audible frequency band, noise perceived by a person when estimating the electrical angle may occur. In order to reduce this noise, it is effective to reduce the high-frequency voltage signal. However, in this case, the inventors have found that the estimation accuracy of the electrical angle is lowered.

  The present invention has been made in the process of solving the above-mentioned problems, and its object is to detect by superimposing a high-frequency voltage signal having a frequency higher than the electrical angular frequency of the rotating machine on the output voltage of the DC-AC converter circuit. Another object of the present invention is to provide a new control device for a rotating machine capable of estimating the rotation angle of the rotating machine based on the detected value of the high-frequency current signal.

  Hereinafter, means for solving the above-described problems and the operation and effect thereof will be described.

  The invention according to claim 1 includes a switching element that selectively connects a terminal of a rotating machine having saliency to each of a positive electrode and a negative electrode of a DC voltage source, and a DC / AC conversion that includes a diode connected in reverse parallel to the switching element. Superimposing means for superimposing a high-frequency voltage signal having a frequency higher than the electrical angular frequency of the rotating machine on the output voltage of the DC-AC converter circuit when controlling the control amount of the rotating machine by operating a circuit; A switching device connected to the positive electrode in a control device for a rotating machine, comprising: estimation means for estimating a rotation angle of the rotating machine based on a detected value of a high-frequency current signal flowing through the rotating machine in response to a high-frequency voltage signal And any one of the switching element connected to the negative electrode and the other from the state where the other is turned on and off, respectively. And when the other is turned off and on, a dead time period in which both are turned off is provided, and the direct current alternating current by the superimposing means is based on the output voltage of the direct current alternating current conversion circuit in the dead time period. An actual high-frequency voltage signal calculating unit that calculates a high-frequency voltage signal that is actually superimposed on the output voltage by operating a conversion circuit; and the estimating unit includes a high-frequency voltage signal calculated by the actual high-frequency voltage signal calculating unit and The rotation angle of the rotating machine is estimated based on the detected value of the high-frequency current signal.

  When the DC / AC converter circuit is used, the voltage applied to the terminal of the rotating machine during the dead time period depends on the polarity of the current flowing through the terminal. The voltage applied to the terminal of the rotating machine during this time can be an error with respect to the high frequency voltage signal intended to be superimposed by the superimposing means. The ratio of the error voltage to the high frequency voltage signal increases as the high frequency voltage signal is reduced. For this reason, the smaller the high-frequency voltage signal, the greater the error that the high-frequency voltage signal actually superimposed has on the intended one.

  Therefore, in the above invention, the actual high frequency voltage signal calculation means calculates the high frequency voltage signal that is actually superimposed. As a result, the rotation angle can be estimated based on the relationship between the detected value of the high-frequency current signal and the high-frequency voltage signal actually superimposed, and as a result, the estimation accuracy can be improved.

  According to a second aspect of the present invention, in the first aspect of the present invention, the estimating means feedback-controls the detected value of the high-frequency current signal or an angular correlation amount that is a parameter calculated based on the detected value to the target value. The angle operation means for operating the rotation angle as the estimated value and the difference between the angle correlation amount as the parameter input to the angle operation means and the target value are added to the actually superimposed high-frequency voltage signal. And quantifying means for quantifying the rotation angle as an error equivalent amount.

  In the above invention, the difference between the angle correlation amount and its target value is quantified as an error equivalent amount based on the actually superposed high-frequency voltage signal, so that the feedback control operation amount can be a highly accurate estimated value. it can.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, the actual high-frequency voltage signal calculating means is configured to convert the DC / AC conversion in the dead time period based on a detected value of a current flowing through a terminal of the rotating machine. The output voltage of the circuit is calculated.

  According to a fourth aspect of the present invention, in the first or second aspect of the invention, the actual high-frequency voltage signal calculation means is superimposed on the basis of a detected value of an output voltage of the DC / AC converter circuit during the dead time period. A high-frequency voltage signal is calculated.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the rotating machine is a multi-phase rotating machine, and an ON operation command period of an operation signal of the DC / AC converter circuit. By further shifting the start point and the end point by the same time, it further has a dead time compensation function that compensates for an error caused by the dead time, and the actual high frequency voltage signal calculating means includes the current flowing through the terminal of the rotating machine. When there is a zero crossing, the high frequency voltage signal to be actually superimposed is calculated based on the output voltage of the DC / AC conversion circuit in the dead time period.

  In the above invention, by having a dead time compensation function, it is possible to avoid the occurrence of an error in the high-frequency voltage signal due to the dead time when there is nothing that zero-crosses the current (phase current) flowing through the terminal. .

1 is a system configuration diagram according to a first embodiment. FIG. The block diagram regarding the estimation process of the rotation angle concerning the embodiment. The time chart which shows the PWM process concerning the embodiment. The time chart which shows the dead time compensation process concerning the embodiment. The time chart explaining the error which arises in the high frequency voltage signal concerning the embodiment. The time chart explaining the error which arises in the high frequency voltage signal concerning the embodiment. The vector figure which shows the error which arises in the high frequency voltage signal concerning the embodiment. The time chart which shows the relationship between the magnitude of a high frequency voltage and the estimation precision of a rotation angle. The figure which shows the calculation method of the dead time error voltage concerning the said embodiment. The system block diagram concerning 2nd Embodiment. The block diagram regarding the estimation process of the rotation angle concerning the embodiment. The block diagram regarding the estimation process of the rotation angle concerning 3rd Embodiment.

<First Embodiment>
Hereinafter, a first embodiment in which a control device for a rotating machine according to the present invention is applied to a control device for a rotating machine as an in-vehicle main machine will be described with reference to the drawings.

  FIG. 1 shows a system configuration diagram according to the present embodiment.

  The motor generator 10 is a three-phase permanent magnet synchronous motor. The motor generator 10 is a rotating machine (saliency pole machine) having saliency. Specifically, the motor generator 10 is an embedded magnet synchronous motor (IPMSM).

  The motor generator 10 is connected to the high voltage battery 12 via the inverter IV. Here, inverter IV has three sets of series connection bodies of switching elements S * p, S * n (* = u, v, w), and the connection point of each series connection body is the U of motor generator 10. , V and W phases. In the present embodiment, insulated gate bipolar transistors (IGBTs) are used as the switching elements S * p and S * n. In addition, diodes D * p and D * n are connected in antiparallel to these.

  In this embodiment, the following is provided as detection means for detecting the state of the motor generator 10 and the inverter IV. First, current sensors 16, 17, and 18 that are configured by Hall elements and detect currents iu, iv, and iw flowing through the phases of the motor generator 10 are provided. Moreover, the voltage sensor 19 which detects the input voltage (power supply voltage VDC) of the inverter IV is provided.

  The detection values of the various sensors are taken into the control device 14 constituting the low pressure system via the interface 13. The control device 14 generates and outputs an operation signal for operating the inverter IV based on the detection values of these various sensors. Here, the signals for operating the switching elements S * p and S * n of the inverter IV are the operation signals g * p and g * n.

  FIG. 2 shows processing performed by the control device 14. In the following, first, “control amount control” will be described, and then “rotation angle estimation processing” will be described.

`` Control amount control ''
The command current setting unit 20 sets a command current idr on the d axis and a command current iqr on the q axis, which are current command values of the rotating two-phase coordinate system, based on the required torque Tr. On the other hand, the currents iu, iv, iw flowing through the phases of the motor generator 10 are, in the dq conversion unit 22, an actual current id on the d axis and an actual current iq on the q axis, which are actual currents in the rotating two-phase coordinate system. Is converted to The deviation calculator 24 calculates the difference between the actual current id (specifically, the actual current id output from the dq converter 22 is filtered by a low-pass filter) and the d-axis command current idr. The deviation calculator 26 calculates the difference between the actual current iq (specifically, the actual current iq output from the dq converter 22 is filtered by a low-pass filter) and the q-axis command current iqr. The current controller 28 feedback-controls the command voltage vdr on the d-axis as an operation amount for feedback-controlling the actual current id on the d-axis to the command current idr and the actual current iq on the q-axis to the command current iqr. A command voltage vqr on the q-axis is calculated as an operation amount for this. Here, the calculation is performed by adding the output of the proportional element and the output of the integral element.

  The three-phase conversion unit 30 converts the command voltages vdr and vqr in the rotating two-phase coordinate system into three-phase command voltages vur, vvr and vwr, and normalizes them with the power supply voltage VDC to thereby convert the duty signal Du. , Dv, Dw are calculated. The dead time compensation unit 34 calculates dead time correction amounts Δvu, Δvv, Δvw for feedforward correction of the duty signals Du, Dv, Dw based on the corresponding phase currents iu, iv, iw. Then, each of the correction units 36, 38, and 40 corrects the duty signals Du, Dv, and Dw based on the dead time correction amounts Δvu, Δvv, and Δvw, respectively. The operation signal generation unit 32 generates the operation signal g * # by PWM processing based on the magnitude comparison between the duty signals Du, Dv, Dw and the carrier.

  FIG. 3 shows details of processing by the operation signal generation unit 32. In the present embodiment, based on the magnitude comparison between the triangular wave carrier CS in which the gradual increase speed and the gradual decrease speed are the same and the gradual increase period and the gradual decrease period are the same, and the duty signals Du, Dv, Dw of each phase, PWM signals gu, gv, and gw are generated. Based on the PWM signal g * (* = u, v, w), an upper arm operation signal g * p and a lower arm operation signal g * n are generated. At this time, by performing dead time generation processing, the operation signal g * # (* = u, v, w; # = p, n) is delayed in the rising timing by the dead time DT with respect to the PWM signal g *. Will be. Note that the update cycle of the duty signals Du, Dv, Dw (command voltages vur, vvr, vwr) is made to coincide with the update cycle of the carrier CS. More specifically, in the present embodiment, the duty signals Du, Dv, Dw are updated at the timing when the carrier CS reaches a peak.

  FIG. 4 shows details of the processing of the dead time compensation unit 34.

  As shown in FIG. 4A, when the phase current i * (* = u, v, w) is positive, current flows through the lower arm diode D * n during the dead time period. The ON period of the operation signal g * p is shorter than the ON period of the PWM signal g * by the dead time DT, and the rising edge is delayed by the dead time DT. For this reason, the dead time compensation unit 34 corrects the duty signal D * to be increased by the dead time correction amount Δv *, so that both the rising edge and the falling edge of the PWM signal g * are “½ of the dead time DT. Correct by one by one. Thereby, the ON period of the operation signal g * p can be matched with the ON period of the PWM signal g * before correction, and the delay amount of the rising edge can be halved.

  As shown in FIG. 4B, when the phase current i * (* = u, v, w) is negative, current flows through the upper arm diode D * p during the dead time period. The on period of the operation signal g * p is longer by the dead time DT than the on period of the PWM signal g *. Therefore, the dead time compensation unit 34 corrects the duty signal D * to be decreased by the dead time correction amount Δv *, so that both the rising edge and the falling edge of the PWM signal g * are “½ of the dead time DT. Correct by one by one. Thereby, the ON period of the operation signal g * p can be matched with the ON period of the PWM signal g * before correction. However, at this time, the rising edge of the operation signal g * p is delayed by “½” of the dead time DT with respect to the rising edge of the PWM signal g * before correction.

  As shown in FIG. 4C, when the phase current i * (* = u, v, w) is inverted from negative to positive in the period from the rising edge to the falling edge of the PWM signal g *, the dead corresponding to the rising edge During the time period, current flows through the upper arm diode D * p, and during the dead time period corresponding to the falling edge, current flows through the lower arm diode D * n. For this reason, the ON period of the operation signal g * p coincides with the ON period of the PWM signal g *. Therefore, in this case, the dead time correction amount Δv * is set to zero.

"Rotation angle estimation process"
The high frequency voltage signal setting unit 50 shown in FIG. 2 sets the high frequency voltage command signal Vhr = (vdhr, vqhr). Here, in this embodiment, vqhr = 0 and vdhr is a signal that reverses its polarity every half cycle of the PWM processing. The superimposing unit 52 corrects the d-axis command voltage vdr output from the current controller 28 with the d-axis component vdhr of the high-frequency voltage command signal and outputs it to the three-phase conversion unit 30.

  On the other hand, the high pass filter 58 extracts harmonic components (high frequency current signals idh, iqh) from the actual currents id, iq. Here, the high frequency component is a component having a higher frequency than the fundamental wave component. In particular, here, the same frequency component as the high-frequency voltage command signal Vhr is extracted. As the high-pass filter 58, for example, a means for outputting a difference between values before and after a half cycle of the PWM signal for the actual currents id and iq may be used.

  The outer product calculation unit 60 basically calculates the outer product value of the high frequency voltage command signal Vhr and the high frequency current signals idh and iqh. This outer product value has a correlation with the angle between the vectors of the high-frequency voltage signal and the high-frequency current signals idh and iqh, and is a parameter (angle correlation amount) having a correlation with the rotation angle of the motor generator 10. On the other hand, the target value setting unit 62 sets the target value of the outer product value. Then, the deviation calculator 64 calculates a difference (error correlation amount) between the outer product value and the target value. This difference is input to the speed calculation unit 66. The speed calculation unit 66 calculates the electrical angular speed ω as the sum of a proportional element and an integral element with the above difference as an input. Then, the angle calculation unit 68 calculates the rotation angle θ as a time integral value of the electrical angular velocity ω. As a result, the rotation angle θ becomes an operation amount for feedback control of the outer product value to the target value.

  The target value is basically zero. This is because the motor generator 10 is an IPMSM and the d-axis inductance Ld is smaller than the q-axis inductance Lq. That is, in this case, if the high-frequency voltage in the d-axis direction is superimposed on the voltage for controlling the control amount as the output voltage of the inverter IV, the high-frequency current signal is also in the d-axis direction, and the outer product value becomes zero. When the outer product value is not zero, the rotation angle θ is manipulated so that the outer product value becomes zero, and the rotation angle θ matches the correct angle.

  However, when the ratio of the change amount of the ON time and OFF time of the operation signal g * # due to the superposition is reduced by decreasing the high frequency voltage signal, the superposition is actually performed. The error due to the dead time DT of the high-frequency voltage signal becomes large, and as a result, the estimation accuracy of the rotation angle θ is lowered. Such an error is due to the provision of the dead time compensation unit 34 so that the phase current i * (* = u, v, w) is inverted from negative to positive during the period from the rising edge to the falling edge of the PWM signal g *. Can be avoided. This is because, as shown in FIG. 4, the ON period of the operation signal g * # is defined by the PWM signal g * by the compensation by the dead time compensation unit 34, and the phase is only “DT / 2”. This is because the line voltage matches that specified by the PWM signal g * before correction because of the delay. In other words, this case is equivalent to the case where the phase of the carrier CS is delayed by “DT / 2” and PWM processing is performed, and no error occurs in the line voltage.

  However, when the phase current i * (* = u, v, w) is inverted from negative to positive during the period from the rising edge to the falling edge of the PWM signal g *, the phase of the operation signal g * n of that phase is Since there is no delay, this is equivalent to advancing only that phase by “DT / 2” compared to the other phases. For this reason, in this case, the line voltage deviates from that defined by the PWM signal g * before correction, and an error occurs in the high-frequency voltage signal. FIG. 5 shows the PWM signal g * after processing by the dead time compensation unit 34. In the example shown in the figure, the U phase has a zero-cross period, and in this case, only the U phase is in the same state as when the voltage is advanced by “DT / 2”. In other words, when the PWM process is performed by retarding the phase of the carrier CS by “DT / 2”, it is equivalent to the voltage of only the U phase being advanced by “DT / 2”. As a result, as indicated by the one-dot chain line in the upper part of the figure, if the high-frequency voltage signal vdh is sequentially superimposed on the signals in the positive and negative directions of the U axis for each half cycle of the PWM, As indicated by the two-dot chain line, the amplitude of the actually superimposed high-frequency voltage signal increases. On the other hand, if the high-frequency voltage signal (vdh) is sequentially superimposed in the negative and positive directions of the U-axis every PWM half cycle, the amplitude of the actually superimposed high-frequency voltage signal is reduced, which is the worst. As shown in FIG. 6, the polarity of the high-frequency voltage signal is inverted. Note that what is indicated by an alternate long and short dash line in FIGS. 5 and 6 is that the d-axis component vdhr of the high-frequency voltage command signal is normalized by the power supply voltage VDC.

  For this reason, as shown in FIG. 7, when the phase current zero-crosses, the high frequency voltage signal Vh that is actually superimposed on the high frequency voltage command signal Vhr has an error. Then, as shown in FIG. 8, this error becomes significant by reducing the high-frequency voltage signal. FIG. 8 shows the time change of the angular correlation amount (outer product value) calculated according to the high-frequency current signal. As shown in the figure, by reducing the high-frequency voltage signal, the amount of angular correlation largely fluctuates near the zero cross of the phase current. In the figure, the fluctuation of the angular correlation amount outside the vicinity of the zero cross of the phase current shown in the figure corresponds to the zero cross period of the other phase not shown.

  Therefore, in the present embodiment, as shown in FIG. 2, the dead time error voltage calculation unit 52 is provided, and the dead time error voltage is based on the power supply voltage VDC, the rotation angle θ, and the phase currents iu, iv, and iw. Is calculated. Here, the phase currents iu, iv, iw are for detecting the zero-cross period. Here, for example, when the phase currents iu, iv, iw are negative immediately before or during switching of the switching state and the absolute value thereof is equal to or less than a specified value, it may be determined that the zero-cross period is reached. Of course, it is possible to use the value immediately after switching, but from the viewpoint of using the value when the detected current value is stable, it is desirable that the value immediately before switching or at the time of switching. Alternatively, the zero cross period may be detected by detecting a change in polarity associated with switching of the switching state.

  Here, the calculated error voltage is as shown in FIG. That is, in the U-phase zero-cross period, when the rise of the ON period of the operation signal gup is shifted to the advance side by “DT / 2” in relation to other phases, the U-phase component of the output voltage of the inverter IV Is changed from “0V” to “VDC”. Therefore, the error voltage is {α · VDC · √ (2/3)} · (−cos θ, sin θ). Here, the ratio α is “DT / Tc”.

  The high-frequency voltage command signals vdhr and vqhr are corrected by the error voltage in each of the error correction units 54 and 56 shown in FIG. The outer product calculation unit 60 calculates the outer product value of the outputs (high frequency voltage signals actually superimposed) of the error correction units 54 and 56 and the high frequency current signals idh and iqh. On the other hand, the target value setting unit 62 sets the target value of the outer product value based on the actually superimposed high-frequency voltage signal that is a signal output from the error correction units 54 and 56. This target value is “0” when the actually superposed high-frequency voltage signal is in the d-axis direction (other than the zero-cross period), while it is “0” when it is not in the d-axis direction (zero-cross period). It is a value other than “”. That is, when the high-frequency voltage signal actually superimposed is not in the d-axis direction, the corresponding high-frequency current signal is considered to be deflected to the d-axis side with respect to the high-frequency voltage signal, and between the high-frequency voltage signal and the high-frequency current signal. Since the angle difference occurs, the outer product value is not zero.

  According to the embodiment described in detail above, the following effects can be obtained.

  (1) Based on the output voltage of the inverter IV during the dead time period, the actually superposed high-frequency voltage signal Vh was calculated, and the rotation angle θ was estimated based on this. Thereby, even when the effective value of the high-frequency voltage signal is 10 times or less of the voltage in the dead time period, the estimation accuracy of the rotation angle θ can be maintained high.

  (2) The error equivalent amount (difference between the outer product value and the target value) was quantified based on the actually superimposed high-frequency voltage signal. Thereby, the operation amount of the feedback control can be set to a highly accurate estimated value.

(3) The dead time error voltage calculation unit 52 calculates the error voltage when the dead time compensation unit 34 is provided and the phase current of the motor generator 10 has zero crossing. As a result, when there is no zero crossing, it is possible to avoid an error in the high frequency voltage signal due to the dead time.
<Second Embodiment>
Hereinafter, the second embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 10 shows a system configuration diagram according to the present embodiment. In FIG. 10, members corresponding to those shown in FIG. 1 are given the same reference numerals for convenience.

  As shown in the figure, in the present embodiment, voltage sensors 70, 72, and 74 that detect the output voltage of each phase of the inverter IV are provided, and the control device 14 uses the output phase voltages vu, vv, and vw detected by these. Then, the dead time error voltage is calculated.

  FIG. 11 is a block diagram relating to processing of the control device 14 according to the present embodiment. In FIG. 11, processes corresponding to those shown in FIG. 2 are given the same reference numerals for the sake of convenience.

The illustrated dead time error voltage calculator 52 calculates a dead time error voltage based on the operation signal g * # and the detected value of the output phase voltage v *.
<Third Embodiment>
Hereinafter, the third embodiment will be described with reference to the drawings with a focus on differences from the first embodiment.

  FIG. 12 is a block diagram relating to processing of the control device 14 according to the present embodiment. In FIG. 12, processes corresponding to the processes shown in FIG. 2 are given the same reference numerals for the sake of convenience.

In the present embodiment, the high-frequency voltage command signal Vhr is alternately set to the voltage in the d-axis direction and the voltage in the q-axis direction, and the multiplication value of the vector norms of the high-frequency current signal for each high-frequency voltage command signal is set as the target value. The rotation angle θ is manipulated to perform feedback control to the target value set by the setting unit 62. This rotation angle estimation method is described in Japanese Patent Application Laid-Open No. 2008-220089. However, in the present embodiment, the target value setting unit 62 sets the target value of the multiplication value based on the outputs of the error correction units 54 and 56 (the actually superimposed high-frequency voltage signal) and the actual currents id and iq. . Here, the actual currents id and iq are used as parameters having a correlation with the target values in view of the fact that the target value changes according to the torque and the phase of the current vector. In calculating the target value, the electrical angular velocity ω may be taken into account.
<Other embodiments>
Each of the above embodiments may be modified as follows.

"Angle operation means"
The angle operation means is not limited to one that calculates the electrical angular velocity ω as the sum of the outputs of the proportional element and the integral element. For example, the electrical angular velocity ω may be calculated as the sum of the outputs of the proportional element, the integral element, and the derivative element. Further, the electrical angular velocity ω is calculated, and the rotation angle θ is not limited to the time integration calculation, but the rotational angle θ may be a parameter for calculating the electrical angular velocity ω.

About quantification means
The target value constituting the “difference between the angular correlation amount such as the outer product value and its target value”, which is an error equivalent amount, is not limited to that calculated based on the actual high frequency voltage signal (vdh, vqh). For example, in FIG. 2 described above, the target value is set to zero, and instead, the angular product obtained by correcting the outer product value output from the outer product calculation unit 60 based on the actual high-frequency voltage signal (vdh, vqh) may be used. .

  The angular correlation amount such as the outer product value constituting the “difference between the angular correlation amount such as the outer product value and its target value”, which is an error equivalent amount, is calculated based on the actual high-frequency voltage signal (vdh, vqh). Not limited to. For example, in FIG. 2, the cross product value of the high frequency voltage command signal (vdhr, vqhr) output from the high frequency voltage signal setting unit 50 and the high frequency current signal (idh, iqh) may be used.

  The angle correlation amount is not limited to that calculated based on the detected value of the high frequency current signal, but may be the high frequency current signal itself. Even in this case, the rotation angle can be estimated by setting a target value corresponding to this.

"About estimation means"
In the third embodiment, as in the technique described in Japanese Patent Application Laid-Open No. 2008-220089, the correction amount for correcting the rotation angle calculated based on the outer product value is feedback-controlled using the multiplication value as its target value. It is good also as the operation amount for doing.

  The estimation means is not limited to one that operates the rotation angle θ to feedback control the angle correlation amount to the target value, and uses the operated rotation angle θ as an estimated value. For example, the estimated rotation angle is manipulated to feedback control the actual angular correlation amount to the assumed target value of the angular correlation amount when the high-frequency voltage signal assumed by the superimposing means is actually superimposed. And means for correcting the manipulated rotation angle based on the high-frequency voltage signal calculated by the actual high-frequency voltage signal calculation means. That is, for example, in FIG. 2, the outer product calculation unit 60 calculates the outer product value of the high-frequency voltage command signal (vdhr, vqhr) and the high-frequency current signal (idh, iqh), and is operated to perform feedback control to zero. The rotation angle θ may be corrected based on the actual high-frequency voltage signal (vdh, vqh). In this case, when the feedback controller calculates the output value according to the input parameter history such as an integral element, the value of the integral element may become an inappropriate value because the dead time error voltage is not zero. In addition, it is possible to suppress the influence of the dead time error voltage when estimating the rotation angle θ. In this case, it is desirable that the correction based on the actual high-frequency voltage signal (vdh, vqh) is made in accordance with the gain of the integral element.

"About superposition means"
The high-frequency voltage command signal is not limited to the voltage signal in the q-axis direction or the d-axis direction.

"Dead time compensation function"
The dead time compensation means is not limited to the one that feedforward corrects the command voltage (Duty signal) based on the polarity of the phase current. For example, the detected value of the output voltage of each phase of the inverter may be feedback controlled to a command value. Even in this case, if correction is performed such that the start point and end point of the on-operation command period are shifted by the same time, it is possible to preferably avoid occurrence of an error in the high-frequency voltage signal outside the zero-cross period.

  Further, even if there is no dead time compensation means for controlling the error of the line average voltage due to the dead time as a direct control amount to zero, the current feedback control shown in FIG. If there is no zero crossing in the current, the line voltage shift due to dead time is fully compensated. For this reason, even in this case, except for the period until the feedback control follows, an error occurs in the actually superimposed high-frequency voltage only when there is a zero crossing. Incidentally, when there is a zero-crossing phase, the error due to the dead time in that phase is, as can be seen from the description of FIG. 5, the error of the average voltage in one cycle Tc of PWM processing although it has a high frequency component. Does not contribute. For this reason, an error occurs in the high-frequency voltage signal in the zero cross period even by the dead time compensation function by feedback control.

  Furthermore, it is not restricted to what carries a dead time compensation function. When this is not installed, the estimation accuracy of the rotation angle is lowered due to the dead time error voltage even outside the period in which the phase current is zero-crossed. For this reason, it is sufficient to calculate the dead time error voltage and estimate the rotation angle in the manner of each of the above embodiments based on the dead time error voltage regardless of the zero cross period. Incidentally, at this time, the dead time error voltage may be calculated using the table shown in FIG. 9 based on the phase current polarity and the phase current polarity change during the dead time period. Note that the polarity or the like of the phase current in the dead time period can be grasped by the polarity or value of the phase current immediately before the dead time period. However, it is also possible to calculate the error voltage during the dead time period based on the output voltage of the inverter IV during the dead time period as described in the second embodiment.

“About Carrier CS”
The timing when the carrier CS becomes a valley may be the update timing of the command voltages vur, vvr, vwr.

  The carrier CS is not limited to a triangular wave, and may be any one as long as the gradual increase period and the gradual decrease period are symmetrical by setting the gradual increase speed and the gradual decrease speed to be equal to each other and the gradual increase period and the gradual decrease period being equal to each other. . In this case, the dead time compensation function makes it easy to set the correction to shift the start point and the end point of the ON operation command period of the operation signal by the same time.

  However, the present invention is not limited to this, and for example, a sawtooth wave may be used. In this case, even if the control amount is feedback-controlled, an error occurs in the high-frequency voltage signal due to the dead time even outside the zero cross period, so it is effective to calculate the dead time error voltage.

“Dead time error voltage calculation timing”
The fact that the phase current is not limited to zero is as described in the section “Dead time compensation means”.

"others"
The current sensors 16, 17, 18 are not limited to those configured with Hall elements. In particular, the current detection value used for calculating the output voltage of the inverter IV during the dead time period can be only the polarity of the current. Therefore, the current detection value is a simple current polarity detection means such as a shunt resistor. Also good. Incidentally, in this case, whether or not it is the zero cross period is determined based on the presence or absence of the polarity change accompanying the switching of the switching state.

  The final control amount of the motor generator 10 is not limited to torque, and may be, for example, a rotational speed. Further, the present invention is not limited to performing current vector control, and for example, torque feedback control may be performed. At this time, if the command voltage is set as the operation amount for controlling the control amount, and the operation signal is set based on the magnitude comparison between the carrier having symmetry and the command voltage, the dead time is set by feedback control of the control amount. A time compensation function can be provided.

  The structural rotating machine having saliency is not limited to the motor generator 10 described above. For example, a synchronous reluctance motor (SynRM) may be used.

  -The rotating machine is not limited to the in-vehicle main machine. For example, an electric motor mounted on a vehicle-mounted power steering may be used.

  DESCRIPTION OF SYMBOLS 10 ... Motor generator, 14 ... Control apparatus, 50 ... High frequency voltage signal setting part, 52 ... Dead time error voltage calculation part, 54, 56 ... Error calculation part, 60 ... Outer product calculation part.

Claims (5)

By operating a DC / AC converter circuit comprising a switching element that selectively connects a terminal of a rotating machine having saliency to each of a positive electrode and a negative electrode of a DC voltage source, and a diode connected in reverse parallel to the switching element, the rotating machine When controlling the control amount, superimposing means for superimposing a high-frequency voltage signal having a frequency higher than the electrical angular frequency of the rotating machine on the output voltage of the DC-AC converter circuit, and depending on the superimposed high-frequency voltage signal, In a control device for a rotating machine, comprising: an estimation unit that estimates a rotation angle of the rotating machine based on a detection value of a high-frequency current signal flowing in the rotating machine;
When switching from the state where either one of the switching element connected to the positive electrode and the switching element connected to the negative electrode and the other are turned on and off to the state where one and the other are turned off and on, respectively, There is a dead time period to turn off,
An actual high-frequency voltage signal calculation means for calculating a high-frequency voltage signal that is actually superimposed on the output voltage by the operation of the DC-AC conversion circuit by the superposition means based on the output voltage of the DC-AC conversion circuit during the dead time period; In addition,
The control device for a rotating machine, wherein the estimating means estimates a rotation angle of the rotating machine based on a high-frequency voltage signal calculated by the actual high-frequency voltage signal calculating means and a detected value of the high-frequency current signal.   The estimation means includes an angle operation means for operating a rotation angle as an estimated value in order to feedback control the detected value of the high-frequency current signal or an angle correlation amount that is a parameter calculated based on the detected value to the target value; Quantification means for quantifying a difference between the angle correlation amount as a parameter input to the angle operation means and its target value as an error equivalent amount of the rotation angle based on the actually superimposed high-frequency voltage signal; The control device for a rotating machine according to claim 1, comprising:   The said high frequency voltage signal calculation means calculates the output voltage of the said DC-AC conversion circuit in the said dead time period based on the detected value of the electric current which flows through the terminal of the said rotary machine. Rotating machine control device.   3. The actual high frequency voltage signal calculating means calculates the actually superimposed high frequency voltage signal based on a detected value of the output voltage of the DC / AC converter circuit in the dead time period. Rotating machine control device. The rotating machine is a multi-phase rotating machine;
A dead time compensation function for compensating for an error caused by the dead time by shifting the start point and the end point of the on operation command period of the operation signal of the DC / AC converter circuit by the same time;
The real high-frequency voltage signal calculating means, when there is a zero crossing among the current flowing through the terminal of the rotating machine, the high frequency actually superimposed on the basis of the output voltage of the DC-AC conversion circuit in the dead time period The control device for a rotating machine according to any one of claims 1 to 4, wherein a voltage signal is calculated.

Images