JP2011066990A - Control device of rotating machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a control device of a rotating machine that estimates a rotor position by a simple method without superimposing high-frequency signals for position estimation, or requiring a complicated operation for position estimation. <P>SOLUTION: The timing of generating an on-signal pulse is shifted by the same amount Δt in each phase of a first switching frequency and a second switching frequency. A current variation component of each phase generated by the shift is detected by a current detector 4. A rotating position estimation value θ<SB>L</SB>is estimated by a position estimation means 5 on the basis of a relational expression between the current variation component of each phase and the rotor position θ. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a control device for a rotating machine that can control a rotating machine such as an induction machine or a synchronous machine by obtaining rotor position information without using a position sensor.

In order to control the rotating machine with high accuracy, position information of the rotating machine is necessary. For this reason, position information has conventionally been obtained by attaching a position sensor or the like to a rotating machine. However, the position sensor is required to be reduced from the viewpoint of cost reduction, space saving, and reliability improvement.
As a position sensorless control method for a rotating machine, there are mainly two methods: a method for estimating the position of the rotating machine from an induced voltage of the rotating machine and a method for estimating the position of the rotating machine using saliency. Since the magnitude of the induced voltage used in the former method is proportional to the speed of the rotating machine, the induced voltage becomes small and the S / N ratio deteriorates at the zero speed and low speed ranges, and the position of the rotating machine is estimated. It becomes difficult.
In the latter method using saliency, a signal for position estimation for estimating the position of the rotating machine must be superimposed and injected into the rotating machine. Since the position can be estimated, position sensorless control using saliency is used at zero speed or low speed.

  In a position sensorless control method using saliency, for example, in Patent Document 1, a dq axis orthogonal coordinate system that rotates in synchronization with a rotor or a magnetic flux vector is used as a control coordinate, and a d axis excitation component current command value is used. The square of the amplitude of the detected current vector, which is the sum of squares of the two-phase current obtained by superimposing the high-frequency signal on the three-phase-two-phase conversion of the current supplied to the motor to be detected, is calculated, and the d-axis excitation current command The value obtained by calculating the square of the amplitude of the command value current vector, which is the sum of the square of the value and the square of the q-axis torque current command value, and subtracting the square of the command value current vector amplitude from the square of the detected current vector amplitude The position of the rotating machine is estimated by calculating the error from the control coordinates based on the above.

  Further, for example, in Patent Document 2, a position sensorless control method using saliency and a bus current detection method are combined. For position estimation, if high frequency voltage is superimposed on the γδ axis, the γ axis will rotate if the DC component of the product of the γ axis component and δ axis component of the high frequency current flowing in the rotating machine converges to zero. It is supposed to be equal to the position. However, since the bus current detection method is used, it is necessary to correct the voltage command in order to regenerate the three-phase current. This correction causes an error in the superimposed harmonic voltage, and as a result, an error also occurs in the estimated position. In order to reduce this error, the voltage vector locus of the superimposed high-frequency voltage is an ellipse.

  In this bus current detection method, for example, as in Patent Document 3, a single current detector is provided between the DC power supply and the inverter, and the three-phase current is determined from the DC bus current and the switching state of the semiconductor switching element of the inverter. There is a bus current detection system that reproduces. Specifically, if a current is detected in a switching pattern in which two different phase currents flow in the bus current, the three-phase current can be detected using the fact that the sum of the three-phase currents is zero.

Japanese Patent No. 3707528 JP 2008-199842 A Japanese Patent Laid-Open No. 2-197295

According to the method of Patent Document 1, a high-frequency signal for position estimation is created on the dq axes, and the calculation of the estimated position requires two pieces of information, that is, a current command and a detected current, so that the calculation increases. There are challenges.
Moreover, in the method of Patent Document 2, there are two problems in combination with the bus current detection method in addition to the above problems. The first is that an error occurs in the applied harmonic voltage by voltage correction for current regeneration, and as a result, an error occurs in the estimated position. Second, when the method as in Patent Document 3 is adopted, an error occurs in the reproduction of the three-phase current. Specifically, the rotating machine current for two phases is detected directly from the bus current, and the remaining one phase is obtained using the fact that the sum of the three-phase currents is zero, but the current for the two phases is detected. Since the timing is different, the sum of the three-phase currents does not become zero.

The present invention has been made to solve the above-described problems, and improves the disadvantage of superimposing a high-frequency signal for position estimation and requiring complicated calculation for position estimation. It is an object of the present invention to obtain a rotating machine control device capable of estimating the rotor position by a simple method.
It is another object of the present invention to provide a rotating machine control device capable of accurately estimating a position even when combined with a simple bus current detection method.

  A rotating machine control device according to the present invention includes an inverter that includes a switching element of each phase, converts a DC voltage of a DC power source into an AC voltage, and outputs the AC voltage to a rotating machine having a saliency, current detection means for detecting a current of the rotating machine, Based on the command value and the rotor position of the rotating machine, on / off signal generating means for generating a pulse-like on / off signal for turning on / off each phase switching element at the switching cycle, and changing the width of the on signal pulse to the switching element for each phase On-signal pulse shift means for shifting the on-signal pulse generation timing in a specific switching cycle and the on-signal pulse generation timing in a switching cycle different from the specific switching cycle by the same time without causing the current to flow Each phase based on the shift of the on signal pulse generation timing from the output of the detection means Fluctuation current component detection means for extracting a fluctuation component of the flow, and position estimation means for estimating and calculating the rotor position of the rotating machine based on the fluctuation component of the current of each phase from the fluctuation current component detection means .

  As described above, the rotating machine control device according to the present invention uses the on signal pulse shift means to generate an on signal pulse in a specific switching period and an on signal pulse in a switching period different from the specific switching period. Since each phase is shifted by the same time, a predetermined voltage is equivalently superimposed on each phase of the rotating machine, and the fluctuation component of the current generated in each phase varies based on this superimposed voltage. When extracted by the current component detection means, the rotor position of the rotating machine can be obtained by calculation from the fluctuation component of the current of each phase by the position estimation means.

It is a figure which shows the structure of the rotary machine control apparatus by Embodiment 1 of this invention. In Embodiment 1 of this invention, it is a figure which shows an example of the on-off signal produced by the on-off signal production | generation means 7. FIG. In Embodiment 1 of this invention, it is a figure which shows an example at the time of shifting an on-off signal. In Embodiment 1 of this invention, when an on-off signal is shifted, it is a figure which shows that the rotating machine current to detect changes. In Embodiment 1 of this invention, it is a figure for demonstrating the method of calculating an estimated position from the fluctuation | variation part of rotary machine current. In Embodiment 2 of this invention, it is a figure which shows an example at the time of shifting an on-off signal. In Embodiment 2 of this invention, when an ON / OFF signal is shifted, it is a figure which shows that the rotating machine current to detect changes. It is a figure which shows the structure of the rotary machine control apparatus by Embodiment 3 of this invention. It is a figure for demonstrating the prior art example of the method of reproducing | regenerating a rotary machine current from the bus-line current between a DC power supply and an inverter.

Embodiment 1 FIG.
The configuration of Embodiment 1 of the present invention is shown in FIG. Here, the rotating machine 1 is an embedded magnet type saliency synchronous machine. An inverter 3 that supplies alternating current power using switching elements Qup, Qun, Qvp, Qvn, Qwp, and Qwn using a DC power supply 2 as an input is connected to the rotating machine 1 through a current detector 4. Position estimation unit 5, the rotating machine current iu detected by the current detector 4, iv, using iw, calculates the estimated position theta _L is a rotor position of the rotary machine 1.

Current control means 6, the rotating machine current iu, iv, iw and using the estimated position theta _L, the voltage command of the rotating machine 1 so that the rotating machine current to follow the current command to the motor in a desired state Vu *, Vv *, Vw * are output. The on / off signal creating means 7 outputs an on / off signal for driving the switching elements Qup, Qun, Qvp, Qvn, Qwp, and Qwn so that the inverter 3 outputs the voltage commands Vu *, Vv *, and Vw *.
The current detector 4 detects the currents iu, iv and iw for three phases, but detects the current for two phases, and the remaining one phase uses the fact that the sum of the three phase currents is zero. You may make it ask.

  The on / off signal creating means 7 creates an on / off signal as shown in FIG. 2 at a predetermined switching cycle, for example. In FIG. 2, Gup, Gun, Gvp, Gvn, Gwp, and Gwn are signals that turn on and off the switching elements Qup, Qun, Qvp, Qvn, Qwp, and Qwn, respectively. When H, the switching elements are on, and when L The switching element is turned off. Also, Qup and Qun, Qvp and Qvn, Qwp and Qwn are complementary, and when one is on, the other is off. When these complementary switching elements are turned on and off, it is common to provide a dead time period during which both switching elements are turned off. Du, Dv, and Dw in FIG. 2 are U, V, and W phase conduction times (pulse widths), and voltage commands Vu *, Vv *, and Vw * are output based on differences in the conduction times of each phase. To do.

  Although not shown individually in FIG. 1, in the present invention, the on / off signal generating means 7 is provided with an on signal pulse shifting means for shifting the generation timing of the on signal pulse, and the position estimating means. 5 includes a fluctuation current component detection means for extracting the fluctuation component of the current of each phase generated by the shift, and the operation of the ON signal pulse shift means and the fluctuation current component detection means will be described below.

FIG. 3 is a diagram for explaining the operation of the ON signal pulse shift means. Here, the on / off timing of the on / off signal is shifted equally. In other words, the generation timing of the on signal pulse is shifted by the same time in each phase without changing the width of the on signal pulse to the switching element of each phase.
In order to simplify the explanation, it is assumed that the voltage commands Vu *, Vv *, Vw * are equal, that is, the flow times Du, Dv, Dw in FIG. 2 are equal. Further, tu1, tu2, and tu3 in the figure are equally spaced at the timing of detecting the U-phase current. Similarly, tv1, tv2, and tv3 are timings for detecting the V-phase current, and tw1, tw2, and tw3 are timings for detecting the W-phase current, and are equally spaced.

  In FIG. 3, the ON / OFF signals Gup, Gvp, and Gwp have the second on / off timing shifted behind the time axis by Δt from the first timing. A state in which the phase currents iu, iv, and iw fluctuate with this shift is shown in the lower part of FIG. Note that the broken lines of Gup, Gvp, Gwp and iu, iv, iw indicate a case where the on / off timing is not shifted.

  FIG. 4 shows two times when the on / off signal timing of FIG. 3 is shifted and when it is not shifted. This is a case where the solid line in FIG. 4 is shifted and the broken line is not shifted. As shown in FIG. 4, the detected rotating machine current fluctuates as much as the timing of the on / off signal is shifted. More specifically, for example, in the U phase, the period during which Gup is H and Gvp and Gwp are L is shifted by Δt, and the detected rotating machine current iu varies by Δihu. However, the rotating machine current iu after the on / off operation does not change. Similarly, in the V phase, the period in which Gvp is H, Gup and Gwp are L shifts by Δt, and the detected rotating machine current iv varies by Δihv. In the W phase, the period in which Gwp is H and Gup and Gvp are L is The detected rotating machine current iw is shifted by Δt and fluctuated by Δihw. The rotating machine currents iv and iw after the on / off operation do not vary. In summary, when the voltage is shifted equally in each phase, that is, when only the upper switching element is on and the other two phases are on when the lower switching element is on, the rotating machine current is shifted by Δt. Can detect fluctuations. However, since ON and OFF are shifted equally, the current after ON / OFF is not affected.

  The fluctuation current component detection means in the position estimation means 5 outputs the output of the current detector 4 at each phase current detection timing tu1, tv1, tw1 of the first switching cycle (first switching cycle) and the second (second switching cycle). The difference from the output of the current detector 4 at each phase current detection timing tu2, tv2, tw2 in the switching cycle is output as each phase current fluctuation component Δihu, Δihv, Δihw.

  Here, the phenomenon in which each phase current fluctuates when the ON signal pulse of each phase is shifted by Δt will be described in more detail. In FIG. 3 and FIG. 4, the generation timing of the ON signal pulse is shifted in the direction in which the second time is delayed by Δt equally for each phase with respect to the first time of the switching cycle. By the way, the rotation cycle corresponding to the speed of the rotor position of the rotating machine 1, which is a detection target of the present invention, is generally sufficiently longer than the switching cycle, which is a cycle for turning on and off the switching element. In other words, it can be said that the switching frequency is sufficiently higher than the rotation frequency. As a result, when viewed on the time scale of the rotation cycle, the time difference between the first and second switching cycles described above can be regarded as almost zero, and the load is a rotating machine including an inductance. By shifting the ON signal pulse equally for each phase, it can be considered that a predetermined voltage determined according to the shift time is equally superimposed on each phase of the rotating machine 1.

Now, assuming that the voltage that can be regarded as superimposed is Δv, the waveform of the voltage Δv is assumed to be close to the waveform of the difference between the solid line waveform and the broken line waveform in FIG. Become.
By the way, when the variable voltage Δv is applied to the rotating machine 1, the amplitude of the rotating machine current of each phase varies depending on the rotor position according to the rotor position due to the saliency of the rotating machine 1, as shown in Equation (1) described later. (See, for example, “Design and Control of Embedded Magnet Synchronous Motor” p. 9- issued by Ohm).

As described above, the present invention realizes an equivalent state in which the fluctuation voltage Δv is superimposed on each phase of the rotating machine 1 by shifting the ON signal pulse equally in each phase, and is established by the application of the fluctuation voltage Δv. The rotor position is estimated using the relational expression (1).
In the present invention, as described in detail below, the rotor position is calculated based on the amplitude ratio of the fluctuation current of each phase by using the expression (1). There is no need to use it. Therefore, as a result, as shown in the figure, the rotor position can be obtained by detecting the current fluctuation component of each phase generated when the ON signal pulse in a specific switching period is shifted by Δt equally in each phase. It can be done.

  Hereinafter, a method for estimating the rotor position using the relational expression of Expression (1) will be described.

However,
Δihu, Δihv, Δihw: each phase current fluctuation component Ih: ratio of average value of fluctuation current amplitude Iha: ratio of change amount of fluctuation current due to rotor position θ: rotor position Δv: fluctuation voltage Note that equation (1) is The relationship between the current fluctuation component and the fluctuation voltage is shown. Strictly speaking, when the right side of the current fluctuation component is multiplied by the reciprocal of the impedance Z common to each phase, the dimensions of both sides coincide with each other. However, in any event, we shall follow the form of the above equation (1) does not affect the method of deriving the following estimated position theta _L.

  By calculating the expression (2) based on the expression (1), it is possible to extract the variations Ihua, Ihva, Ihwa due to the rotor position among the phase current fluctuation components.

  Further, by calculating the expression (3) based on the expression (2), the coefficient Δv · Iha / 2 on each right side of the expression (2) can be obtained from the amount of change of each phase current fluctuation component depending on the rotor position. it can.

  By substituting Equation (3) into Equation (2), the rotor position can be obtained by performing an inverse cosine calculation from any one of the change amounts Ihua, Ihva, and Ihwa of each phase current fluctuation component. Alternatively, the rotor position can also be obtained by performing an arctangent calculation after three-phase / two-phase conversion of Ihua, Ihva, and Ihwa.

However, if the inverse cosine calculation or arc tangent calculation is used, the required calculation amount and storage capacity increase. Therefore, a method for calculating the rotor position using linear approximation will be described below.
First, it is divided into sections I to VI as shown in FIG. 5 based on the relative magnitude relationship of the change amounts Ihua, Ihva, and Ihwa of each phase current fluctuation component, and the center position of each section is represented by θ as shown in Expression (4). _Let it be _M.

In each section, among the variations Ihua, Ihva, and Ihwa, the one that zero-crosses at the center of each section is a sin-sin function, but this sin-sin function is regarded as a straight line and is approximated by a straight line. A deviation Δθ _ML between the center position θ _{M of} each section and the estimated rotor position θ _L (≈rotor position θ) is obtained.

Incidentally, Ihzc of formula (5) are variations of Ihua, Ihva, the value of those zero-cross at the center theta _M of each section of the Ihwa. Then, as shown in Expression (6), Δθ _ML obtained from Expression (5) and the center position θ _M can be added to determine the estimated rotor position θ _L.

  As described above, according to the first embodiment of the present invention, a special voltage source for voltage superposition is not required, and therefore, it can be used for a long time because the number of parts is reduced. Detects each phase current fluctuation component that changes according to the rotor position depending on the saliency of the rotating machine with simple processing such as shifting the timing equally for each phase for the second time with respect to the first time of the switching cycle In addition, the rotor position can be estimated from the detected phase current fluctuation components, and the amount of calculation for estimation can be reduced.

Embodiment 2. FIG.
In the first embodiment, the on signal pulse generation timing is shifted equally for each phase for the second time with respect to the first time of the switching cycle, and the rotor position is estimated from the current fluctuation component at that time. In the second embodiment, the on-signal pulse generation timing is periodically shifted so that the position can be estimated continuously and more accurately.
In the second embodiment of the present invention, the operations of the on / off signal creating means 7 and the position estimating means 5 are different from those in the first embodiment.

  That is, the on signal pulse shift means in the on / off signal creation means 7 periodically shifts the on and off timings of the on / off signal equally as shown in FIG. In FIG. 6, on / off signals Gup, Gvp, and Gwp are shifted on and off the time axis by Δt every time the on / off is repeated. Broken lines of Gup, Gvp, and Gwp indicate a case where the on / off timing is not shifted.

  FIG. 7 shows two on / off states in FIG. A solid line in FIG. 7 is a case where the on / off timing is shifted after the time axis, and a broken line is a case where the on / off timing is shifted before the time axis. As shown in FIG. 7, the detected rotating machine current fluctuates as much as the on / off signal is shifted. More specifically, for example, in the U phase, the period in which Gup is H, Gvp and Gwp are L is shifted by 2Δt, and the detected rotating machine current iu varies by Δihu. However, the rotating machine current iu after the on / off operation does not change. Similarly, in the V phase, the period in which Gvp is H, Gup and Gwp are L is shifted by 2Δt, and the detected rotating machine current iv is changed by Δihv, and in the W phase, the period in which Gwp is H and Gup and Gvp are L is The detected rotating machine current iw shifts by 2Δt and fluctuates by Δihw. The rotating machine currents iv and iw after the on / off operation do not vary. In summary, when the voltage is shifted equally in each phase, that is, when only the upper switching element is on and the period during which the other two phases are on the lower switching element is shifted by 2Δt, Can detect fluctuations. In this case, the period of variation corresponds to a time in which the on / off signal is repeatedly turned on and off twice. However, since ON and OFF are shifted equally, the current after ON / OFF is not affected.

  The fluctuation current component detection means in the position estimation means 5 includes a filter that passes the signal of the shift operation repetition period by the above-described ON signal pulse shift means, and the signal detected by the current detector 4 at each phase current detection timing. Further, the signal obtained through the filter is extracted as each phase current fluctuation component Δihu, Δihv, Δihw.

Next, a method for estimating the rotor position will be described. As in the first embodiment, each phase current fluctuation component Δihu, Δihv, Δihw obtained at a certain timing as described above is used as the above equation (1). Although it is possible to obtain an estimated position theta _L of the rotating machine by applying the following, it will be described here further method of increasing the estimation accuracy.

  That is, in the example of FIG. 6, since the ON signal pulse is alternately shifted back and forth, the positive and negative polarity of the current fluctuation component of each phase changes alternately. Therefore, the absolute value or the square value of the current fluctuation components Δihu, Δihv, Δihw extracted for each current detection cycle, and thus every switching cycle, is integrated over a predetermined period. As the integration period is increased, the accuracy is improved, but at least a half period of the period of the fluctuation voltage Δv is required.

  The amplitude ratios Ihu, Ihv, and Ihw of each phase current fluctuation component obtained by integration are shown in Expression (7). However, a necessary coefficient k (k is a real number where k> 0) is set along with the integration. A low-pass filter may be used for extracting the amplitude ratio.

  Using Expression (7), the amount of change Ihua, Ihva, Ihwa due to the rotor position of the fluctuation current of each phase is extracted by the calculation of Expression (8).

Method for calculating the estimated position theta _L of the rotating machine 1 from the equation (8) is the same as in the first embodiment.
As described above, in the second embodiment of the present invention, the ON / OFF timing of the ON / OFF signal is periodically shifted equally, so that the rotor position can always be detected continuously. In addition, it is possible to narrow the pass band of the band pass filter when extracting the fluctuations Δihu, Δihv, Δihw of the rotating machine current, and the integration period when extracting the amplitude ratios Ihu, Ihv, Ihw of each phase current fluctuation component It is possible to improve the accuracy of position estimation by increasing the time constant or the time constant of the low-pass filter.

Embodiment 3 FIG.
The configuration of the third embodiment of the present invention is shown in FIG. In the first embodiment and the second embodiment, the current of the rotating machine 1 is detected from the current detector 4 provided on the AC side of the inverter 3, but in the third embodiment, the DC power source 2 and the inverter 3 are detected. The current of the rotating machine 1 is regenerated by the output current regenerating means 10 from the bus current detector 9 provided between and the on / off signal. The operations of the position estimation unit 5 and the current control unit 6 are the same as those in the first and second embodiments.

  The principle of regenerating the rotating machine current by the output current regenerating means 10 will be described below. Referring to FIG. 3 and FIG. 6, the on / off signal and current detection timing according to the present invention are shown in FIG. That is, the on / off signal creating means 7 of the present invention creates an on / off signal so that the on signal pulses of each phase do not overlap in time in each switching period. Then, the output of the bus current detector 9 is sampled in the time zone of the ON signal pulse of each phase.

  Therefore, at the U-phase current detection timings tu1, tu2, and tu3, only the U-phase is turned on among the semiconductor switching elements connected to the positive side of the DC power supply 1, and the U-phase current is detected from the bus current detector 9. it can. Similarly, for the V phase and the W phase, the V phase current and the W phase current can be detected from the bus current detector 9 at the V phase current detection timings tv1, tv2, tv3 and the W phase current detection timings tw1, tw2, tw3, respectively. . In this way, the current of the rotating machine 1 can be regenerated from the bus current detector 9.

  On the other hand, in the conventional method, the rotating machine current is detected from the bus current as shown in FIG. That is, Gup, Gvp, and Gwp in FIG. 9 are signals for turning on / off the switching elements of the U, V, and W phases of the inverter 3 connected to the positive side of the DC power supply 1, and when H, the switching elements are turned on. , When L, turn off. At the detection timing tu ′ in FIG. 9, only the U-phase is turned on among the semiconductor switching elements connected to the positive side of the DC power supply 1, so the U-phase current is detected from the bus current detector 9. Similarly, the W-phase current is detected from the bus current detector 9 at the detection timing tw ′. The remaining V-phase current is calculated using the fact that the sum of the three-phase currents is zero.

However, since the detection timings of the currents for the two phases are different, the sum of the three-phase currents when they are used is not zero, and the remaining one phase is calculated by utilizing the fact that the sum of the three-phase currents is zero. An error occurs when computing.
In addition, when the fluctuation voltage for estimating the rotor position is superimposed, since only the current for two phases can be detected accurately, the processing of Expression (2) and Expression (8) is performed from the current fluctuation component of Expression (1). Therefore, it is not possible to extract the estimated position information by removing the average value of the fluctuation amplitude.

  Further, in the case of FIG. 9 as an example, the detected U-phase current and W-phase current vary if the U-phase on-timing is changed, and the detected W-phase current varies if the V-phase on-timing is changed. Thus, it is difficult to detect the three-phase fluctuation current when the fluctuation voltage is applied equally to the three phases.

  On the other hand, in the present invention, as shown in FIGS. 3 and 6 described in the first and second embodiments, the on and off timing of the on / off signal is shifted equally, that is, the on signal pulse Without changing the width, the current fluctuation component of each phase generated when the generation timing of the ON signal pulse of each phase is shifted equally in each phase is detected. Further, by shifting the on / off signal of each phase, the current value after completion of on / off, that is, the detection current of the other phase is not affected. Furthermore, since it is not necessary to utilize that the sum of the three-phase currents is zero, it is possible to accurately detect each phase current fluctuation component directly from the single bus current detector 9. Therefore, the estimation of the rotor position of the rotating machine 1 can be easily and accurately calculated.

  As described above, in Embodiment 3 of the present invention, the rotating machine 1 can be driven without a position sensor, and in addition, the current detector of the inverter 3 can be integrated into one, and the rotating machine control can be performed in a small and low cost. A device can be configured.

In each of the above embodiments, the method of shifting the ON signal pulse based on the operation of the switching element connected to the positive side of the DC power source 1 has been described. Needless to say, the operation of the connected switching element may be used as a reference.
The on / off signal generating means 7 of the present invention generates an on / off signal for each phase based on a voltage command which is an output of the current control means 6 which operates by inputting a current command, a rotating machine current and a rotor position. However, the present invention is not limited to this, and the present invention is similarly applied to an apparatus for creating an on / off signal for each phase based on a signal created by inputting at least a command value and a rotor position. Can do.

Although the rotating machine 1 of the present invention has been described as an embedded magnet type synchronous machine, it goes without saying that the present invention can be applied to other synchronous machines such as a synchronous reluctance type synchronous machine.
Furthermore, various things, such as a battery, a diode rectifier circuit, and a PWM converter, can be considered as the DC power source of the present invention.

1 rotating machine, 2 DC power supply, 3 inverter, 4 current detector, 5 position estimation means,
6 current control means, 7 on / off signal creation means, 8 rotating machine control device,
9 Bus current detector, 10 Output current regeneration means.

Claims (5)

Inverter comprising a switching element for each phase, converting a DC voltage of a DC power source into an AC voltage and outputting it to a rotating machine with saliency, current detecting means for detecting current of the rotating machine, command value and rotor of the rotating machine ON / OFF signal generating means for generating a pulse-like ON / OFF signal for turning ON / OFF the switching element of each phase in a switching cycle based on the position, without changing the width of the ON signal pulse to the switching element of each phase. ON signal pulse shift means for shifting the ON signal pulse generation timing in the switching period and the ON signal pulse generation timing in a switching period different from the specific switching period by the same time in each phase, and the current detection means Based on the shift of the on signal pulse generation timing from the output of Fluctuating current component detecting means for extracting the current fluctuation component of each phase, and position estimating means for estimating and calculating the rotor position of the rotating machine based on the current fluctuation component of each phase from the fluctuation current component detecting means. Provided rotating machine control device. The on-signal pulse shifting means determines the generation timing of the on-signal pulse in a specific first switching period and the generation timing of the on-signal pulse in a second switching period subsequent to the first switching period. Shift the phase for the same amount of time,
The fluctuation current component detection means uses, as the current fluctuation component, an output difference of the current detection means at a predetermined detection timing set within the ON signal pulse generation period of the first and second switching periods. The rotating machine control device according to claim 1, wherein: The on-signal pulse shifting means determines the generation timing of the on-signal pulse in a specific first switching period and the generation timing of the on-signal pulse in a second switching period subsequent to the first switching period. Repeat the operation of shifting by the same time in the phase,
The fluctuation current component detection means includes a filter that allows a signal having a repetition period of a shift operation by the ON signal pulse shift means to pass, and a signal obtained from the current detection means through the filter is the current fluctuation component. The rotating machine control device according to claim 1, wherein: The said current detection means is inserted between the said inverter and the said rotary machine, It detected the electric current of each phase of the said rotary machine, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. Rotating machine control device. The on / off signal creating means creates the on / off signal so that the on signal pulses of each phase do not overlap in time in each switching period,
The current detecting means is inserted between the DC power supply and the inverter to detect the current of the DC power supply, and the output of the current detector is sampled in the time zone of the ON signal pulse of each phase 4. The rotating machine control device according to claim 1, further comprising an output current regeneration unit configured to regenerate and calculate an output current of each phase. 5.

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