JP7073915B2 - Rotating machine control device and control method - Google Patents

Description

The present invention relates to a control device and a control method for a rotating machine.

Various rotary machines have been proposed that detect the rotational position of the rotor without a sensor. For example, in Patent Document 1, when a pulse is applied to a field winding, a current flowing through the armature winding is detected, and the position of the rotor of the rotor is obtained by an operation using the current. Further, there is also known a rotor control device that injects an alternation signal into the armature winding of the rotor and detects the magnetic pole position of the rotor by using a signal having the same frequency component as the alternation signal (Patent Document 2). ).

Japanese Unexamined Patent Publication No. 2005-39891 Japanese Unexamined Patent Publication No. 2006-136123

However, when a pulse is applied to the field winding, there is a problem that the accuracy in determining the position of the rotor is low. Further, since the current used for the calculation requires an absolute value, there is a problem that the accuracy of the current sensor affects the accuracy of the position of the rotor. In addition, in the method of injecting the alternation signal into the armature winding of the rotor, the noise immunity is lowered because the voltage of the alternation signal is controlled to be zero, and there remains a concern about the accuracy of the rotor position. There was a challenge.

According to one embodiment of the present invention, a rotary machine (14u, 14v, 14w) having a field winding (18) in the rotor (16) and a multi-phase winding (14u, 14v, 14w) having three or more phases in the stator (12). The control device (20) of 10) is provided. This control device has a search signal superimposing unit (82) that superimposes a search signal (IdS, IqS) having a constant amplitude and a constant electrical phase on the multi-phase winding, and the field winding. After temporarily setting the position of the rotor with respect to the stator and the field current sensor (70) that detects the flowing field current at an arbitrary angle, the search signal is transmitted by using the search signal superimposing unit. It is provided with a position estimation unit (80) which is superimposed on the phase winding and estimates the position of the rotor with respect to the stator by using the field current. According to this form, since the position estimation unit estimates the position of the rotor using the field current, it is not necessary to have a salient polarity, and the initial position of the magnetic pole can be estimated easily and with high accuracy by a simple method.

It is explanatory drawing which shows the schematic structure of the rotary machine and the control device thereof. It is a flowchart which estimates a rotor position. It is explanatory drawing which shows the search signal and its phase. It is explanatory drawing which shows the field current at the time of superimposing the phase of the d-axis current and the d-axis current, and the search signal in the case where there is almost no error in the position where the rotor is temporarily set. It is explanatory drawing which shows the current signal and d-axis current phase at the time of superimposing the search signal in the case where there is almost no error of the position where a rotor is tentatively set. It is explanatory drawing which shows the field current If when the phase of d-axis current and d-axis current and the search signal S are superposed when there is an error in the position where a rotor is provisionally set. It is explanatory drawing which shows the current signal and d-axis current phase at the time of superimposing the search signal in the case where there is an error in the position where a rotor is tentatively set.

FIG. 1 is an explanatory diagram showing a schematic configuration of a rotary machine 10 and a control device 20 thereof. The rotary machine 10 includes a stator 12 and a rotor 16. The stator 12 includes three-phase windings 14u, 14v, 14w. The three-phase windings 14u, 14v, and 14w are star-connected. The three-phase windings 14u, 14v, and 14w may be delta-connected. The rotor 16 includes a field winding 18.

The control device 20 includes a current command generation unit 30, a three-phase winding current control unit 40, a field current control unit 60, and a position estimation unit 80. The current command generation unit 30 uses the torque T required for the rotary machine 10 to generate the d-axis current command IdC, the q-axis current command IqC, and the field current command IfC. Here, the torque T required for the rotary machine 10 is calculated by using, for example, the opening degree of the accelerator pedal of the vehicle and the speed of the vehicle when the rotary machine 10 is mounted on the vehicle.

The three-phase winding current control unit 40 controls the voltages Vu, Vv, Vw applied to the three-phase windings 14u, 14v, 14w by using the currents of the three-phase windings 14u, 14v, 14w of the stator 12. The three-phase winding current control unit 40 includes adders 41, 42, difference calculators 43, 44, PI control units 46, 48, a three-phase voltage command conversion unit 50, a driver 52, an inverter 54, and the like. It includes a three-phase current sensor 56 and a dq-axis current conversion unit 58.

The three-phase current sensor 56 measures the currents Iu, Iv, and Iw flowing through the three-phase windings 14u, 14v, and 14w. The dq-axis current conversion unit 58 converts the currents Iu, Iv, and Iw into the d-axis current Id and the q-axis current Iq.

The adder 41 adds the d-axis search signal IdS to the d-axis current command IdC. The adder 42 adds the q-axis search signal IqS to the q-axis current command IqC. The difference calculator 43 calculates the difference between the d-axis current command IdC to which the d-axis search signal IdS is added and the d-axis current Id. The difference calculator 44 calculates the difference between the q-axis current command IqC to which the q-axis search signal IqS is added and the q-axis current Iq.

The PI control unit 46 calculates the d-axis voltage command VdC by PI control using the difference between the d-axis current command IdC to which the d-axis search signal IdS is added and the d-axis current Id. The PI control unit 48 calculates the q-axis voltage command VqC by PI control using the difference between the q-axis current command IqC to which the q-axis search signal IqS is added and the q-axis current Iq.

The three-phase voltage command conversion unit 50 converts the d-axis voltage command VdC and the q-axis voltage command VqC into the three-phase voltage commands VuC, VvC, and VwC. The driver 52 uses the three-phase voltage commands VuC, VvC, and VwC to generate switching signals Swu, Swv, and Sww for turning on / off the switching element provided inside the inverter 54. The inverter 54 turns on / off the internal switching element by the switching signals Sw, Swv, Sww, and generates the voltages Vu, Vv, Vw applied to the three-phase windings 14u, 14v, 14w.

The field current control unit 60 controls the voltage Vf applied to the field winding 18 by using the field current If of the field winding 18 of the rotor 16. The field current control unit 60 includes a difference calculator 62, a PI control unit 64, a driver 66, an inverter 68, and a field current sensor 70.

The field current sensor 70 measures the field current If flowing through the field winding 18 of the rotor 16. The difference calculator 62 calculates the difference between the field current command IfC and the field current If. The PI control unit 64 generates the field voltage command VfC by using the difference between the field current command IfC and the field current If. The driver 66 uses the field voltage command VfC to generate the switching signal Swf of the inverter 68. The inverter 68 turns on / off the internal switching element by the switching signal Swf, and generates the voltage Vf applied to the field winding 18.

The position estimation unit 80 estimates the phase θ ^ of the initial position of the rotor 16 by using the field current If. The position estimation unit 80 includes a search signal superimposition unit 82, a high-pass filter 84, a zero cross detection unit 86, a rotor position estimation unit 88, a compensation unit 90, and an adder 92.

The search signal superimposing unit 82 generates the search signals IdS and IqS for a certain period of the rising edge of the rotation of the rotor 16 and sends them to the adders 41 and 42 of the three-phase winding current control unit 40. In the present embodiment, the search signals IdS and IqS are signals having a constant amplitude and a constant electrical phase change, for example, a sine wave or a chord wave current signal. The period of the search signals IdS and IqS is, for example, 1 ms to 10 ms (100 Hz to 1 kHz), more preferably 4 ms to 6 ms. The fixed period of the rise of rotation of the rotor 16 is, for example, the number of cycles of the search signals IdS and IqS, which is a period of 3 to 4 cycles. As described above, in the present embodiment, the three-phase windings 14u, 14v, 14w are used for a certain period of the rising edge of the rotation of the rotor 16, for example, the number of cycles of the search signals IdS and IqS, and only for a period of 3 to 4 cycles. The voltage corresponding to the search signals IdS and IqS is superimposed.

The high-pass filter 84 extracts the current signal Ifac of the frequency component corresponding to the search signals IdS and IqS from the field current If measured by the field current sensor 70. The zero cross detection unit 86 detects the zero cross point of the current signal Ifac. The zero cross point is a point where the value of the current signal Ifac becomes zero. The rotor position estimation unit 88 estimates the initial position of the rotor 16 by using the position of the zero cross point and the change of the current signal Ifac before and after the zero cross point. The compensation unit 90 compensates for the phase change due to the frequencies of the search signals IdS and IqS, the time constant of the high-pass filter 84, and the time constant of the rotor 16. The adder 92 calculates the phase of the initial position of the rotor 16 by adding the phase change of the compensating unit 90 to the phase θ ^ of the initial position of the rotor 16 estimated by the rotor position estimation unit 88.

FIG. 2 is a flowchart for estimating the rotor position. In step S100, after temporarily setting the rotor 16 at an arbitrary angle, the three-phase winding current control unit 40 and the field current control unit 60 start starting the rotating machine 10.

In step S110, the search signal superimposing unit 82 applies the search signals IdS and IqS having a constant amplitude and a constant electrical phase to the voltages Vu, Vv and Vw applied to the three-phase windings 14u, 14v and 14w. By generating and superimposing the d-axis current command IdC and the q-axis current command IqC, the search signals IdS and IqS are superposed on the currents of the three-phase windings 14u, 14v and 14w.

FIG. 3 is an explanatory diagram showing a search signal and its phase. The lower graph of FIG. 3 is a graph showing the d-axis search signal IdS and the q-axis search signal IqS, and the upper graph is a graph showing the phases of the search signal IdS and the search signal IqS. In the present embodiment, a sine wave or a chord wave current signal is used as the search signals IdS and IqS, and the search signals IdS and IqS are signals having a constant amplitude and a constant electrical phase change.

In step S120 of FIG. 2, the field current sensor 70 acquires the field current If.

FIG. 4 is an explanatory diagram showing the phase of the d-axis current and the d-axis current and the field current If when the search signals IdS and IqS are superimposed when there is almost no error in the position where the rotor 16 is temporarily set. The lower graph of FIG. 4 shows the d-axis current of the stator 12 and its phase. The upper graph of FIG. 4 shows the field current If. In the rotating machine 10 having the field winding 18 in the rotor 16 and the three-phase windings 14u, 14v, 14w in the stator 12, the field winding 18 of the rotor 16 interferes only with the d-axis of the stator 12. , Does not interfere with the q-axis. When the rotating machine 10 is started, the field current If when the search signals IdS and IqS are superimposed increases or decreases in synchronization with the d-axis search current IdS, as shown in the upper graph.

In step S130 of FIG. 2, the position when the field current If becomes the peak values P1, P2, P3, P4, P5, and P6 of FIG. 4 and the phase at that position are acquired. Here, the peak values P1, P2, P3, P4, P5, and P6 of the field current If are the minimum values and the maximum values when the field current If increases or decreases. Here, whether or not the field current If has reached a peak value (minimum value or maximum value) must be determined by observing changes in the field current If before and after that, and it is difficult to determine. Therefore, in the present embodiment, as described below, the high-pass filter 84 is used to extract the current signal Ifac, and the field current If is the peak value (minimum value) using the zero cross point at which the current signal Ifac becomes zero. Or the position where it becomes the maximum value) and the phase at that position are acquired.

FIG. 5 is an explanatory diagram showing the current signals Ifac and the d-axis current phase when the search signals IdS and IqS are superimposed when there is almost no error in the position where the rotor 16 is temporarily set. The upper graph of FIG. 5 shows the current signal Ifac, and the lower graph shows the d-axis current phase. The current signal Ifac is synchronized with the search signal and has a substantially sinusoidal shape. As can be seen from the upper graph of FIG. 5, in the vicinity of the zero cross points Z1, Z2, and Z3 where the current signal Ifac becomes zero, the current signal Ifac transitions from plus to minus or from minus to plus, so that the zero cross detection unit 86 Can easily acquire the positions of the zero cross points Z1, Z2, and Z3 from the current signal Ifac value. As shown in FIG. 5, the current signal Ifac may have an offset. The fact that the current signal Ifac has an offset means that a DC component is added to the current signal Ifac and the current signal Ifac is shifted to the plus side or the minus side. In FIG. 5, a graph is drawn assuming that the current signal Ifac has an offset. The zero cross detection unit 86 can easily determine the zero cross points Z1, Z2, Z3 and the like even when the current signal Ifac has an offset.

Next, the zero-cross detection unit 86 can easily obtain the phases PhZ1 and PhZ2 when the current signal Ifac becomes the zero-cross points Z1 and Z2 by using the graph in the lower part of FIG. Here, when the current signal Ifac has the shape of a sinusoidal wave having an offset, the shape from the peak (maximum value or minimum value) to the zero cross point becomes symmetric. Therefore, the zero-cross detection unit 86 can obtain the phase PhP1 of the peak P1 sandwiched between the two zero-cross points Z1 and Z2 as an intermediate phase between the phase PhZ1 of the zero-cross point Z1 and the phase PhZ2 of the zero-cross point Z2. That is, the zero-cross detection unit 86 can easily obtain the phase PhP1 of the peak P1 by performing the calculation of (PhZ1 + PhZ2) / 2. In the current signal Ifac, the shapes from the peak to the two zero cross points sandwiching the peak are symmetrical, so that any value of the offset of the current signal Ifac is sandwiched between the two zero cross points Z1 and Z2. The phase PhP1 of the peak P1 does not change. For example, in FIG. 5, when the offset becomes small, the phase PhZ1 of the zero cross point Z1 becomes small, but the phase PhZ2 of the zero cross point Z2 becomes large, and as a result, the value of (PhZ1 + PhZ2) / 2 does not change. .. As described above, the zero-cross detection unit 86 can easily obtain the phase at which the field current If becomes the peak by using the phases of the two zero-cross points sandwiching the peak regardless of the offset value. ..

In step S140 of FIG. 2, the rotor position estimation unit 88 estimates the initial position of the rotor 16 by utilizing the fact that the peak value of the field current If occurs at either the current phase of 90 degrees or 270 degrees. The rotor position estimation unit 88 determines whether the peak value of the field current If is 90 degrees or 270 degrees in phase based on the inclination of the current signals Ifac at the zero cross points Z1 and Z2. Specifically, at the zero cross point, when the slope of the current signal Ifac is negative, it is about 0 degrees, when it is positive, it is about 180 degrees, and when the peak value of the current signal Ifac is the minimum value, it is about 90 degrees. By setting the maximum value to about 270 degrees, the directions of the north and south poles of the rotor 16 can be specified. The rotor position estimation unit 88 sets the difference between the angle of the rotor 16 provisionally set in step S100 of FIG. 2 and the phase PhP1 of the peak P1 calculated by using the phases of the two zero cross points, 90 degrees or 270 degrees. It is estimated to be the phase θ ^ at the initial position of 16.

In step S150, the adder 92 adds a signal from the compensation unit 90 to the phase of the initial position of the rotor 16 estimated by the rotor position estimation unit 88 to compensate for the phase delay. The phase delay can be easily calculated by using the time constant of the high-pass filter 84 and the time constant of the field winding 18 of the rotor 16. The time constant of the high-pass filter 84 can be calculated by using the frequencies of the search signals IdS and IqS and the inductance and capacitance of the components constituting the high-pass filter 84. The time constant of the field winding 18 can be calculated by using the frequencies of the search signals IdS and IqS, and the inductance and capacitance of the field winding 18. When the change in phase due to the time constant of the high-pass filter 84 and the time constant of the field winding 18 of the rotor 16 is not compensated, the compensation unit 90 and the adder 92 can be omitted.

In step S160, the position estimation unit 80 determines whether or not the start of the rotating machine 10 is completed. The position estimation unit 80 determines that the start of the rotary machine 10 is completed when the search signals IdS and IqS are superimposed a predetermined number of times, for example, 3 to 4 times after the start of the rotary machine 10 is started. .. If the start of the rotary machine 10 is not completed, the position estimation unit 80 returns to step S110.

FIG. 6 is an explanatory diagram showing the phases of the d-axis current Id and the d-axis current and the field current If when the search signals IdS and IqS are superimposed when there is an error in the position where the rotor 16 is temporarily set. FIG. 7 is an explanatory diagram showing the current signal Ifac and the d-axis current phase when the search signals IdS and IqS are superimposed when there is an error in the position where the rotor 16 is temporarily set. Comparing FIGS. 6 and 7 with FIGS. 4 and 5, the d-axis current phase is out of phase due to an error in the position where the rotor 16 is temporarily set.

Even if there is an error in the position where the rotor 16 is temporarily set, the phase when the zero cross point of the current signal Ifac or the current signal Ifac becomes the peak value is obtained as in the case where there is no error in the position where the rotor 16 is temporarily set. be able to. Here, in FIGS. 4 and 5, the phase when the current signal Ifac reaches a peak value (minimum value) is about 90 degrees, but in FIGS. 6 and 7, the current signal Ifac has a peak value (minimum value). ), The phase is significantly deviated from about 90 degrees. The difference between 90 degrees and the phase when the current signal Ifac reaches the peak value (minimum value) is the phase θ ^ of the initial position of the rotor 16, that is, the phase of the position when the rotor 16 is provisionally set. That is, in the examples shown in FIGS. 4 and 5, since there is almost no error in the initial position of the rotor 16, the phase of the peak value (minimum value) is about 90 degrees. On the other hand, in the examples shown in FIGS. 6 and 7, since the position error of the initial position of the rotor 16 is large, the phase of the peak value (minimum value) is deviated from the initial position of the rotor 16 by 90 degrees by the position error. As described above, according to the present embodiment, the phase θ ^ of the initial position of the rotor 16 can be easily estimated regardless of whether or not there is a position error in the initial position of the rotor 16.

As described above, according to the present embodiment, after temporarily setting the position of the rotor 16 with respect to the stator 12 at an arbitrary angle, the search signals IdS and IqS are connected to the search signal superimposing unit 82 in the three-phase windings 14u, 14v, 14w. Since it is provided with a position estimation unit 80 that estimates the position of the rotor 16 with respect to the stator 12 by superimposing it on the field current If, it is not necessary to have a salient pole, and the initial stage of the rotor 16 is easy and highly accurate by a simple method. The phase θ ^ of the position can be estimated.

According to the present embodiment, since the search signals IdS and IqS are current signals of a sine wave or a chord wave, the search signal can be given to the estimated d-axis and the estimated q-axis in a well-balanced manner, and the rotor 16 can be performed with high accuracy. Position estimation can be performed. Further, when the search signals IdS and IqS are sine wave or cosine wave current signals, it is possible to suppress the generation of high-order harmonic currents in the field current If.

The phase of the field current corresponds to the position of the rotor. According to the present embodiment, the position estimation unit 80 can easily estimate the phase θ ^ of the initial position of the rotor by using the phase of the peak value of the field current.

According to the present embodiment, the position estimation unit 80 extracts the current component Ifac using the high-pass filter 84, and extracts the phase of the peak value of the current component Ifac. Since the phase of the peak value of the current component Ifac and the phase of the peak value of the field current If are the same, the phase of the peak value of the field current If can be easily obtained.

According to the present embodiment, the position estimation unit 80 sets the phase intermediate between the phases of two adjacent zero cross points where the current signal Ifc zero crosses as the phase of the peak value. It is easier to find the phase of the zero cross point than to find the phase of the peak value. Further, even if the current signal has an offset, the phase of the peak value can be acquired without being affected by the offset.

・ Modification example:
In the above embodiment, a sine wave or a chord wave current signal is used as the search signals IdS and IqS, but a sine wave or a chord wave voltage signal may be used. When the search signals IdS and IqS are voltage signals, an adder may be provided between the PI control units 46 and 48 and the three-phase voltage command conversion unit 50 instead of the adders 41 and 42. Further, as long as the signal has a constant amplitude and the electrical phase changes at a constant cycle, it may be a signal other than a sine wave or a chord wave, for example, a current signal or a voltage signal of a triangular wave or a rectangular wave.

In the above embodiment, the high-pass filter 84 is used to acquire the current signal Ifac, and the zero cross point of the current signal Ifac is used to obtain the phase of the peak value. The peak value of the current If may be obtained.

In the above embodiment, the zero cross detection unit 86 of the position estimation unit 80 obtains the zero cross point at which the current signal Ifac becomes zero, and obtains the phase of the peak value by finding the middle of the two zero cross points. The zero-cross detection unit 86 includes a differentiating circuit that differentiates the current signal Ifac, and the phase of the current signal Ifac when the differential value crosses zero may be the phase of the peak value. Since the peak value of the current signal Ifac is a maximum value or a minimum value, the differential value of the current signal Ifac becomes zero at the peak value. Therefore, the phase in which the differential value crosses zero can be set as the phase of the peak value.

In the above embodiment, the position estimation unit 80 estimates the position of the rotor 16 within the period in which the field current If is started when the rotating machine 10 is started, but searches during normal operation after starting the rotating machine 10. The positions of the rotor 16 may be estimated by superimposing the signals IdS and IqS. However, the position estimation unit 80 estimates the position of the rotor 16 by superimposing the search signals IdS and IqS within the period in which the field current If is started when the rotating machine 10 is started to estimate the position of the rotor 16. The phase θ ^ of the position of the rotor 16 can be estimated without giving a special period for the rotor 16.

In the above embodiment, the search signal superimposing unit 82 inputs the search signals IdS and IqS to the adders 41 and 42, so that the search signals IdS are applied to the currents Iu, Iv and Iw flowing in the three-phase windings 14u, 14v and 14w. , IqS is superimposed, but by inputting the search signals IdS and IqS to the current command generation unit 30, the search signals IdS and IqS are transmitted to the currents Iu, Iv and Iw flowing in the three-phase windings 14u, 14v and 14w. It may be superimposed.

In the above embodiment, the stator 12 has been described as having three-phase windings 14u, 14v, 14w, but the windings may be multi-phase windings having three or more phases. The winding may be, for example, a 4-phase or 5-phase winding.

The present invention is not limited to the above-described embodiment, and can be realized with various configurations within a range not deviating from the gist thereof. For example, the technical features of the embodiments corresponding to the technical features in each of the embodiments described in the column of the outline of the invention may be used to solve some or all of the above-mentioned problems, or a part of the above-mentioned effects. Or, in order to achieve all of them, it is possible to replace or combine them as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be appropriately deleted. For example, a part of the configuration realized by hardware in the above embodiment can be realized by software. In addition, at least a part of the configuration realized by software can be realized by a discrete circuit configuration.

The present invention can be realized as the following forms.

(1) According to one embodiment of the present invention, the rotor (16) has a field winding (18), and the stator (12) has a multi-phase winding (14u, 14v, 14w) having three or more phases. A control device (20) for the rotary machine (10) is provided. This control device has a search signal superimposing unit (82) that superimposes a search signal (IdS, IqS) having a constant amplitude and a constant electrical phase on the multi-phase winding, and the field winding. After temporarily setting the position of the rotor with respect to the stator and the field current sensor (70) that detects the flowing field current at an arbitrary angle, the search signal is transmitted by using the search signal superimposing unit. It is provided with a position estimation unit (80) which is superimposed on the phase winding and estimates the position of the rotor with respect to the stator by using the field current. According to this form, since the position estimation unit estimates the position of the rotor using the field current, it is not necessary to have a salient polarity, and the phase of the initial position of the magnetic pole is estimated easily and with high accuracy by a simple method. can.

(2) In the above embodiment, the search signal may be a current signal of a sine wave or a chord wave, or a voltage signal of a sine wave or a chord wave. According to this form, the search signal can be given to the estimated d-axis and the estimated q-axis in a well-balanced manner, and the position of the rotor can be estimated with high accuracy. Further, if it is a sine wave or cosine wave current signal or voltage signal, it is possible to suppress the generation of high-order harmonic current in the field current.

(3) In the above embodiment, the position estimation unit may estimate the position of the rotor with respect to the stator by using the peak value of the field current (If). Since the phase of the field current corresponds to the position of the rotor, the position estimation unit can easily estimate the phase of the initial position of the rotor by using the peak value of the field current.

(4) In the above embodiment, the position estimation unit may further include a filter (84) that extracts a current signal (Ifac) of a frequency component corresponding to the search signal from the field current. According to this form, the peak value of the field current can be easily obtained.

(5) In the above embodiment, the position estimation unit may use the intermediate phase of two adjacent phases at which the current signal crosses zero as the phase of the peak value. According to this embodiment, even if the current signal has an offset, the phase of the peak value can be acquired without being affected by the offset.

(6) In the above embodiment, the position estimation unit may differentiate the current signal and set the phase at which the differential values cross zero as the phase of the peak value. Since the peak value of the current signal is a maximum value or a minimum value, the differential value becomes zero at the peak value. According to this embodiment, the position estimation unit can set the phase in which the differential value obtained by differentiating the current signal zero crosses as the phase of the peak value.

(7) In the above embodiment, the position estimation unit sets the phase of the peak value to 90 degrees or 270 degrees, and sets the difference between the angle temporarily set at an arbitrary position and the phase of the peak value as the initial position of the rotor. May be. According to this form, the north pole and the south pole can be discriminated without taking any special measures.

(8) In the above embodiment, the position estimation unit may determine whether the temporarily set angle is 90 degrees or 270 degrees depending on the inclination of the current signal at the zero crossing point. According to this form, the directions of the north and south poles of the rotor can be discriminated without taking any special measures.

(9) In the above embodiment, the position estimation unit compensates for the phase change by using the frequency of the search signal, the time constant of the filter, and the time constant of the field winding of the rotor. It may be provided with a unit. According to this embodiment, the position estimator compensates for the phase change by using the frequency of the search signal, the time constant of the filter, and the time constant of the field winding of the rotor, so that the position of the rotor The phase can be estimated with high accuracy.

(10) In the above embodiment, the position estimation unit may estimate the position of the rotor within the period for raising the field current at the time of starting the rotating machine from off to on. According to this embodiment, the phase of the initial position of the rotor can be estimated without giving a special period for estimating the position of the rotor.

The present invention can be realized in various forms, for example, in a form such as a rotor position estimation method for a rotating machine, in addition to a control device for a rotating machine.

10 ... Rotating machine 12 ... Stator 14u, 14v, 14w ... 3-phase winding 16 ... Rotor 18 ... Field winding 20 ... Control device 30 ... Current command generator 40 ... 3-phase winding Current control unit 41, 42 ... Addition Instrument 43, 44 ... Difference calculator 46, 48 ... PI control unit 50 ... 3-phase voltage command conversion unit 52 ... Driver 54 ... Inverter 56 ... 3-phase current sensor 58 ... dq-axis current conversion unit 60 ... Field current control unit 62 ... Difference calculator 64 ... PI control unit 66 ... Driver 68 ... Inverter 70 ... Field current sensor 80 ... Position estimation unit 82 ... Search signal superimposition unit 84 ... High pass filter 86 ... Zero cross detection unit 88 ... Rotor position estimation unit 90 ... Compensation Part 92 ... Adder Id ... d-axis current Iq ... q-axis current IdC ... d-axis current command IqC ... q-axis current command IdS, IqS ... Search signal If ... Field current IfC ... Field current command Ifac ... Current signal Iu, Iv, Iw ... Current P1 to P6 ... Peak PhP1 ... Phase PhZ1 ... Phase PhZ2 ... Phase Swf, Sw, Swv, Sw ... Switching signal T ... Torque VdC ... d-axis voltage command VqC ... q-axis voltage command Vf ... Voltage VfC ... Magnetic voltage command VuC, VvC, VwC ... Voltage command Vu, Vv, Vw ... Voltage Z1, Z2, Z3 ... Zero cross point θ ^ ... Phase of initial position of rotor

Claims (9)

In the control device (20) of the rotary machine (10) having the field winding (18) in the rotor (16) and the multi-phase winding (14u, 14v, 14w) of three or more phases in the stator (12). There,
A search signal superimposing unit (82) that superimposes a search signal (IdS, IqS) whose amplitude is constant and whose electrical phase changes at a constant cycle on the polyphase winding.
A field current sensor (70) that detects the field current flowing in the field winding, and
After temporarily setting the position of the rotor with respect to the stator at an arbitrary angle, the search signal is superimposed on the polyphase winding using the search signal superimposing unit, and the field current is used to superimpose the search signal on the stator. A position estimation unit (80) that estimates the position of the rotor with respect to the
Equipped with
The search signal is a sine wave or chord wave current signal, or a sine wave or chord wave voltage signal.
The position estimation unit is a control device that estimates the position of the rotor with respect to the stator using the peak value of the field current (If) . The control device according to claim 1 .
The position estimation unit is a control device further comprising a filter (84) for extracting a current signal (Ifac) having a frequency component corresponding to the search signal from the field current. The control device according to claim 2 .
The position estimation unit is a control device in which a phase intermediate between two adjacent phases in which the current signal crosses zero is set as the phase of the peak value. The control device according to claim 2 .
The position estimation unit is a control device that differentiates the current signal and sets the phase at which the differential values cross zero as the phase of the peak value. The control device according to claim 3 or 4.
The position estimation unit is a control device in which the phase of the peak value is 90 degrees or 270 degrees, and the difference between the angle temporarily set at an arbitrary position and the phase of the peak value is the initial position of the rotor. The control device according to claim 5 .
The position estimation unit is a control device that determines whether the temporarily set angle is 90 degrees or 270 degrees according to the inclination of the current signal at the zero crossing point. The control device according to claim 5 or 6.
The position estimation unit is a control device including a compensation unit that compensates for a phase change using the frequency of the search signal, the time constant of the filter, and the time constant of the field winding of the rotor. The control device according to any one of claims 1 to 7 .
The position estimation unit is a control device that estimates the position of the rotor within a period in which the field current is raised at the time of starting the rotating machine from off to on. It is a control method of a rotary machine (10) having a field winding (18) in the rotor (16) and a multi-phase winding (14u, 14v, 14w) having three or more phases in the stator (12).
Temporarily set the position of the rotor with respect to the stator at an arbitrary angle.
A search signal (IdS, IqS) having a constant amplitude and a constant electrical phase change in the polyphase winding, and is a sine wave or cosine wave current signal, or a sine wave or cosine wave voltage signal. Superimpose the search signal that is
Detecting the field current flowing in the field winding,
The position of the rotor with respect to the stator is estimated using the peak value of the field current (If) .
Control the rotary machine,
Control method.

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