JP6099488B2 - AC rotating machine control device - Google Patents

Description

  The present invention relates to a control device for an AC rotating machine that can obtain the rotational speed and rotor position of the AC rotating machine without using a speed sensor or a position sensor.

In a control device for an AC rotating machine such as a synchronous machine or an induction machine, a speed sensor or a position sensor is usually used to rotate the rotating machine at a desired output or rotation speed. However, since these sensors are disadvantageous in terms of fault tolerance and maintenance, a method for detecting the magnetic pole position and rotational speed of an AC rotating machine is known without using these sensors.
These methods are mathematically calculated and detected based on rotating machine constants such as armature resistance, inductance, and induced voltage constant. By setting the rotating machine constant in the control device in advance, the magnetic pole position And the rotation speed can be detected.

However, if there is an error in the set value of the armature resistance, there is a problem that an error occurs in the calculation of the magnetic pole position and the rotational speed. Especially at low speeds, the ratio of the voltage drop due to the armature resistance in the output voltage increases, so the influence of the setting value of the armature resistance becomes significant, and the control stability is controlled by the error in the detected value of the magnetic pole position and rotation speed. descend.
Moreover, this is particularly noticeable in the case of a rotating machine with a small capacity and a large armature resistance, but the armature resistance value increases due to the temperature rise in the rotating machine due to long-time operation, and the armature resistance constant set at the start of operation And the stability of the control deteriorates due to errors in the detected values of the magnetic pole position and the rotational speed.

  As described above, when the rotation speed and the rotor position are obtained without a sensor, it is necessary to be able to estimate the resistance value of the armature resistance with high accuracy.

In this regard, for example, Patent Document 1 discloses a method of estimating a resistance value from a deviation between an estimated current value obtained by calculation using a magnetic flux observer (adaptive observer) and a detected current value at the start of operation.
However, in the case of Patent Document 1, there is a problem that an error in the estimated resistance value increases due to a temperature rise due to long-time operation.

  On the other hand, for example, Non-Patent Document 1 obtains the estimated speed and thus the rotor position by the adaptive observer sequentially during operation, and at that time, the observer gain H is set from the viewpoint of ensuring the stability of the analytical calculation. It is also possible to estimate the resistance value using an adaptive observer with the same gain, and to estimate the speed and position using this estimated resistance value.

Japanese Patent No. 4238652

“Position sensorless control of PM motor using adaptive observer on rotating coordinates”, D. 123, No. 5, 2003

By the way, in Non-Patent Document 1, an observer gain H for ensuring stability in an analytical calculation of an estimated speed using an adaptive observer is obtained.
Therefore, as will be described in detail later, based on Popov's superstable theory, the transfer function between the input and output of the corresponding control circuit is strongly positive, that is, the absolute value of the phase difference between the input and output is at all frequencies. On the other hand, the observer gain H is set so as to satisfy the condition of 90 degrees or less.

  However, the transfer function in the case of estimating and calculating the resistance value using the observer gain H has a problem that the robustness and reality may not be satisfied depending on the rotation speed, and the resistance cannot be estimated stably during operation.

  The present invention has been made to solve such a problem, and with respect to the armature resistance of an AC rotating machine that fluctuates due to a temperature change due to long-term operation, the resistance value can be stably set even during a rotating operation. An object of the present invention is to provide a control device for an AC rotating machine that can be estimated, suppresses a speed estimation error due to resistance fluctuation, and does not degrade the driving performance of the AC rotating machine.

A control device for an AC rotating machine according to the present invention includes a control unit that generates a voltage command based on a command from a higher control system, a voltage applying unit that applies a voltage to the AC rotating machine based on a voltage command, and a current of the AC rotating machine. Current detecting means for detecting and outputting detected current, speed observing means for calculating and outputting the estimated speed of the AC rotating machine using an adaptive observer based on the voltage command, the detected current and the estimated resistance value of the AC rotating machine, and the detected current In the control device for the AC rotating machine provided with the resistance observation means that calculates and outputs the estimated resistance value based on the estimated speed, the speed observation means and the resistance observation means include an observer gain that is set by calculation using an adaptive observer. The estimated speed and the estimated resistance value are calculated and output in the state where the necessary condition for the transfer function in each calculation is stable. I der,
In the first invention, the speed observation means further calculates and outputs the estimated speed and the estimated current using an adaptive observer set to the first observer gain based on the voltage command, the detected current, and the estimated resistance value. age,
The resistance observing means calculates an estimated resistance value based on the detected current and the estimated current calculated by the speed observing means, and determines whether or not the necessary condition is satisfied based on the estimated speed. An update determination unit that updates the output of the estimated resistance calculation unit only when
In the second invention, the speed observation means further calculates and outputs the estimated speed using an adaptive observer set to the first observer gain based on the voltage command, the detected current, and the estimated resistance value.
The resistance observation means calculates and outputs an estimated resistance value using an adaptive observer set to the second observer gain based on the voltage command, the detected current, and the estimated speed,
The resistance observation means includes an update determination unit that calculates an estimated acceleration based on the estimated speed and updates the output of the estimated resistance value only when the estimated acceleration is equal to or less than a predetermined set value.

As described above, in the control apparatus for an AC rotating machine according to the present invention, the operation for calculating and outputting the estimated speed by the speed observation means, and the operation for calculating and outputting the estimated resistance value by the resistance observation means are performed by the adaptive observer. The armature of an AC rotating machine that fluctuates due to temperature changes due to long-term operation, etc., since the necessary conditions for the stable transfer function in each operation are satisfied, including the observer gain set by the used operation As for the resistance, the resistance value can be stably estimated even during the rotation operation, and the speed estimation error due to the resistance fluctuation can be suppressed.
Further, in the first invention, in the speed region where the resistance estimation calculation cannot be stably performed, the update of the estimated resistance is stopped. As a result, the speed observing means and the resistance observing means have the AC rotating machine rotating. However, it is possible to calculate and output the estimated speed and the estimated resistance value in a stable state.
Further, the resistance observing means of the second invention calculates an estimated current using an observer gain different from that of the speed observing means so as to ensure stability of the transfer function in the calculation of the estimated resistance value. In addition, by estimating the resistance value, the resistance value can always be calculated stably even during the rotation operation.

It is a figure which shows the structure of the control apparatus of the AC rotary machine in Embodiment 1 of this invention. It is a Bode diagram of a transfer function including an observer gain H set by calculating an estimated speed using an adaptive observer. FIG. 6 is a Bode diagram of a transfer function including an observer gain H when calculating an estimated resistance value using an adaptive observer. It is a figure which shows the internal structure of the control means 3 of FIG. It is a figure which shows the internal structure of the speed observation means 5 of FIG. It is a figure which shows the internal structure of the state observation part 53 of FIG. It is a figure which shows the internal structure of the resistance observation means 6 of FIG. It is a figure which shows the structure of the control apparatus of the alternating current rotating machine in Embodiment 2 of this invention. It is a figure which shows the internal structure of the resistance observation means 8 of FIG. This shows an observer gain set to a constant value when calculating the estimated resistance value. FIG. 11 is a Bode diagram of a transfer function including the observer gain shown in FIG. 10. An observer gain H2 for calculating an estimated resistance value is set to a gain that changes according to speed. FIG. 13 is a Bode diagram of a transfer function including the observer gain H2 shown in FIG. It is a figure which shows the internal structure of the estimated resistance calculating part 88 of FIG.

Embodiment 1 FIG.
1 is a diagram showing a configuration of a control device for an AC rotary machine according to Embodiment 1 of the present invention. In FIG.
The AC rotating machine 1 is a synchronous motor, and here is a synchronous machine using a permanent magnet.
The AC rotating machine 1 is connected to a current vector detecting means 2 as a current detecting means for detecting the current vector of the AC rotating machine 1 and a voltage applying means 4 corresponding to a power converter such as an inverter for applying a voltage. Yes.

The current vector detection means 2 detects the three-phase currents iu, iv, iw of the AC rotating machine 1, and the coordinate converter 21 uses the estimated magnetic pole position from the speed observing means 5 to be described later. Coordinates are converted into currents on the dq axis, which are known as orthogonal coordinates that rotate in synchronization with the rotor, and are output as detected current vectors (ids, iqs).
In order to detect the three-phase current, in addition to detecting the current for all three phases, the three-phase current may be obtained by detecting two phases and using the fact that the sum of the three-phase currents is zero. The three-phase current may be calculated from the inverter bus current, the current flowing through the switching element, and the state of the switching element.

As shown in FIG. 4, the control means 3 subtracts the detected current vectors (ids, iqs) from the current command vectors (idref, iqref) given from the external control system by the adder / subtracter 31, respectively. . The current controller 32 outputs a voltage command vector (vd, vq) by proportional-integral control so that there is no deviation between the current command vector output from the adder / subtractor 31 and the detected current vector.
The coordinate converter 33 converts the voltage command vector (vd, vq) from the dq axis to a three-phase voltage command vector (vu, vv, vw) in stationary coordinates using the estimated magnetic pole position θ0 and outputs it.

  The voltage application unit 4 applies a voltage to the AC rotating machine 1 based on the three-phase voltage command vector output from the control unit 3.

  The speed observation means 5 calculates an estimated speed and an estimated magnetic pole position by using an adaptive observer using a three-phase voltage command vector, a detected current vector, and an estimated resistance value output from the resistance observation means 6 described later. To do.

  In addition, although the method of estimating and calculating the internal state of an AC rotating machine using an adaptive observer is not limited to the above-mentioned Patent Document 1 and Non-Patent Document 1, it is also well known in order to facilitate understanding of the explanation in the later stage. Here, first, the principle of estimating the internal state of the AC rotating machine using the adaptive observer will be described.

First, a method for estimating the rotational speed of a rotating machine using an adaptive observer will be described, and then a method for estimating an armature resistance value will be described.
If the AC rotating machine to be controlled is a synchronous machine using a permanent magnet, the equation of state on the αβ axis used for the control can be expressed by equations (1) to (3).
Here, the voltage command vector on the αβ axis is defined as (Vα, Vβ), the armature reaction vector is defined as (φαs, φβs), the rotor magnetic flux vector is defined as (φαr, φβr), and the current vector is defined as (iα, iβ). , R represents an armature resistance, L represents an armature inductance, and ωr represents a rotation speed of the rotor.

  A state equation for estimating the internal state of the AC rotating machine using the adaptive observer from the equations (1) to (3) can be defined by the equations (4) to (6).

  Here, consider a case where an error from the rotational speed ωr appears in the estimated speed ωr0. When the speed error is set to Δω = ωr0−ωr, Expression (7) can be derived by subtracting Expression (1) from Expression (4).

  Equation (7) indicates that a component (−ΔωJΦr0) orthogonal to the estimated rotor magnetic flux Φr0 is input to the transfer function G (s) and a current deviation vector (iα0−iα, iβ0−iβ) is output. ing. Further, h11 to h42 of the observer gain H are determined so that the estimated speed can be calculated stably. For example, the gains h1 to h4 shown in FIG. 5 of Non-Patent Document 1 are replaced with h11 = h22 = h1, −h12 = h21 = h2, h31 = h42 = h3, −h32 = h41 = h4, and the gain is set. Thus, it is possible to design an observer that can stably estimate the speed.

  Further, the estimated speed can be calculated by proportional-integral control as shown in Expression (8) using the proportional constant kpω and the integral constant kiω.

Next, a method for estimating a resistance value using an adaptive observer will be described.
Expressions for estimating the armature resistance value of the AC rotating machine using the adaptive observer from Expressions (1) to (3) can be defined by Expressions (9) and (10). Here, for simplicity, ωr0 = ωr is assumed to be a steady state in which the error Δω does not appear in the speed estimation value.

  When an error due to the change in resistance value is set to ΔR = R0−R, Expression (11) can be derived by subtracting Expression (1) from Expression (9).

  Equation (11) indicates that the component (ΔR * Is0) in the estimated current Is0 direction is input to the transfer function G (s) and the current deviation vectors (iα0−iα, iβ0−iβ) are output. .

  Further, the estimated resistance value R0 can be calculated by proportional-integral control as shown in Expression (12) using the proportional constant kpR and the integral constant kiR.

  As described above, the internal state is estimated using the adaptive observer, the speed estimation is estimated by the equation (8), the component orthogonal to the estimated rotor magnetic flux Φr0, and the resistance estimation is estimated by the equation (12). An estimation calculation is performed by proportional-integral control using each component in the current Is0 direction.

  By the way, as described above, the estimated current value used in the method of estimating and calculating the armature resistance is calculated from an observer designed to stably obtain the estimated speed. That is, it is necessary to design the observer gain so that the transfer function G (s) from the current deviation vector (i0-i) to Δω shown in Expression (7) does not become unstable.

  The necessary condition for the transfer function G (s) to be stable is Popov's superstability, which is a stability determination method for a feedback control system composed of a linear stationary block and a nonlinear time-varying block having the transfer function G (s). Based on the theory, the transfer function G (s) that is this linear stationary block is strongly positive, that is, the absolute value of the phase difference between the input and output of the transfer function G (s) is 90 degrees or less for all frequencies. Is to become.

  Here, taking the observer gain of Non-Patent Document 1 as an example, consider the transfer function of the estimated speed calculation. The calculation of the estimated speed only needs to consider the transfer function of the component orthogonal to the rotor magnetic flux, and therefore the transfer characteristic shown in Equation (18) of Non-Patent Document 1 may be considered.

FIG. 2 shows a Bode diagram of a transfer function in an estimated speed calculation in a certain synchronous rotating machine. In FIG. 2, transfer functions when rotating at 0 Hz, 32 Hz, and 128 Hz are illustrated, and the upper part is a gain diagram and the lower part is a phase diagram.
Focusing on the variation in phase difference of the transfer function in FIG. 2, it can be seen that the variation in phase is within ± 90 degrees, that is, the estimated speed calculation having this transfer function operates stably. Even when the speed is varied, the phase fluctuation is within ± 90 degrees, so that the speed can be stably estimated regardless of the speed.

  Next, a transfer function of resistance estimation calculation is considered using the above-described observer. Since the calculation of the resistance estimation appears in the same direction as the estimated current, the transfer function of Equation (13) may be considered.

  With regard to the transfer function GR (s) of Expression (13), the transfer characteristic as shown in FIG. According to FIG. 3, in the stop state where ωr = 0, the phase fluctuation operates stably within 90 degrees. However, when ωr ≠ 0, the phase variation of the transfer characteristic exceeds ± 90 degrees. That is, during the rotation of ωr ≠ 0, the resistance estimation transfer function GR (s) is not strong and real, the resistance estimation using the stator estimation current becomes unstable, and an error or deviation occurs in the estimated resistance value. there's a possibility that.

  Therefore, in the first embodiment of the present invention, as the estimated resistance value used for calculating the estimated speed, only the value calculated in a state where the necessary condition for the transfer function to be stable is satisfied, In effect, the speed observation means and the resistance observation means can calculate and output the estimated speed and the estimated resistance value, respectively, in a stable state.

Hereinafter, the description of the speed observation means 5 will be continued with reference to FIG.
The speed estimation calculation is performed by estimating the current vector and the rotor magnetic flux vector, which are the internal state of the AC rotating machine 1, as shown in the equations (4) to (8) described above, and the estimated current vector and the detected current vector. The estimated speed can be calculated from the deviation and the estimated magnetic flux vector.

  In the first embodiment, in order to configure the system on the dq axis, the speed observing means 5 that calculates the estimated speed ωr0 using the equations (14) to (18) is configured.

The operation of the speed observation means 5 will be described with reference to FIG.
In the figure, an adder / subtracter 51 subtracts a detected current vector (ids, iqs) from an estimated current vector (ids0, iqs0), which is an output of a state observation unit 53 described later, and outputs a current deviation vector (e1, e2). . The coordinate converter 52 converts the three-phase voltage command vector (vu, vv, vw) that is the output of the control means 3 into the dq-axis voltage command vector (vds, vqs) that is the orthogonal rotation coordinate.

The state observing unit 53 determines the estimated speed ωr0 and the alternating current of the AC rotating machine 1 from the voltage command vector (vds, vqs), the current deviation vector (e1, e2), and the estimated resistance value R0 output from the resistance observing means 6 described later. The estimated current vector (ids0, iqs0) of the rotating machine 1 is calculated. The integrator 54 integrates the estimated speed ωr0 and outputs the estimated magnetic pole position θ0.
Since the voltage command vector (vds, vqs) has the same value as the output (vd, vq) of the current controller 32 of the control means 3, the coordinate converter 52 is set as (vds, vqs) = (vd, vq). It can be omitted.

Next, the operation of the state observation unit 53 will be described with reference to FIG.
The matrix calculator 531 outputs the result of multiplying the voltage command vector (vds, vqs) ^T by the matrix B. T represents a transposed matrix. The matrix calculator 532 outputs a result obtained by multiplying the current deviation vector (e1, e2) ^T by the matrix H. Note that the estimated speed ωr0 input to the matrix calculator 532 is used to create the matrix H1.

The matrix calculator 533 outputs the result of multiplying the estimated value of the armature reaction vector and the estimated value of the magnetic flux vector (φds0, φqs0, φdr0, φqr0) ^T by the matrix Aω1.
The estimated speed ωr0 and the estimated resistance value R0 input to the matrix calculator 533 are used to create the matrix Aω1 (see Expression (17)).

The adder / subtractor 534 outputs a vector obtained by adding / subtracting the output of the matrix calculator 531, the output of the matrix calculator 532, and the output of the matrix calculator 533. The integrator 535 integrates the vector output from the adder / subtractor 534 for each element, and outputs it as a vector (φds0, φqs0, φdr0, φqr0) ^T.
The above is the part corresponding to Equation (14). Note that the left side of Equation (14) corresponds to the input portion of the integrator 535.

Matrix calculator 536 multiplies matrix C1 by vector (φds0, φqs0, φdr0, φqr0) ^T , and outputs estimated current vector (ids0, iqs0) ^T. This part corresponds to equation (15).
Matrix calculator 537 multiplies matrix C2 by vector (φds0, φqs0, φdr0, φqr0) ^T , and outputs estimated magnetic flux vector Φr0 (φdr0, φqr0) ^T. This part corresponds to equation (16).
The speed estimator 538 outputs the estimated speed ωr0 according to the equation (18).

As described above, the speed observing means 5 calculates and outputs the estimated speed and the estimated magnetic pole position using the voltage command vector, the detected current vector, and the estimated resistance value output from the resistance observing means 6 described later.
The gains h1 _{11 to} h1 ₄₂ of the observer gain H1 can be set to change the value of each gain according to the estimated speed ωr0 as described in FIG. 9 of Japanese Patent No. 4672236, for example. .

Next, the resistance observation means 6 will be described. As described above, in the resistance estimation using the estimated current value output from the speed observing means 5, as shown in FIG. 3, the necessary condition for the transfer function to be stable is not satisfied except for the stopped state, that is, The stability of the resistance estimation calculation is not guaranteed, and an error occurs in the estimated resistance value during rotation, or the estimated value diverges.
Therefore, in the first embodiment, an update determination unit is provided in the resistance estimation calculation, and in a speed region where stability is not guaranteed, the resistance estimation calculation is stopped and a new estimated value is not output, thereby being stable even during the rotation operation. Thus, the resistance value can be estimated.

FIG. 7 is an internal configuration diagram of the resistance observing means 6 in the first embodiment. Hereinafter, the operation of the resistance observation unit 6 will be described with reference to the drawings.
The adder / subtractor 61 subtracts the detected current vector (ids, iqs) from the estimated current vector (ids0, iqs0) from the speed observation means 5 and outputs a current deviation vector (e1, e2). This is equivalent to the operation of the adder / subtractor 51.
The multiplier 62 multiplies each element of the current vector deviation (e1, e2), which is input by an update determination signal sig output from an update determination unit 64 described later, and outputs the result.
From the current deviation vector (e1, e2) multiplied by the update determination signal sig and the estimated current vector (ids0, iqs0), the estimated resistance calculation unit 63 calculates the estimated resistance by proportional-integral control as shown in Expression (19). The value R0 is calculated and output.

  The update determination unit 64 determines whether to perform resistance estimation calculation based on the input estimated speed ωr0, that is, determines whether or not the necessary condition for the transfer function in the resistance estimation calculation to be stable is satisfied, and an update determination signal Output sig.

  As described above, when the estimated speed ωr ≠ 0, the stability of the resistance estimation calculation using the estimated current vector calculated by the speed observation unit 5 is not guaranteed. Therefore, the update of the resistance estimation calculation output is controlled by changing the update determination signal sig according to the speed as in Expression (20).

  The update determination unit 64 outputs sig = 1 when the stability is ensured and the estimated resistance is calculated, and sig = 0 when the stability is not ensured and the calculation is stopped. Thus, the multiplier 62 performs an operation, that is, when sig = 1, the current deviation vector (e1, e2) is output as it is, and no operation is performed, that is, when sig = 0, 0, 0) is output.

  From equation (19), if the current deviation vector is a zero vector, the internal state of proportional integral does not change and is equivalent to the resistance estimation calculation stopping, and the value calculated before that is updated. It will output continuously without doing.

  As described above, update determination unit 64 of the control device for an AC rotary machine according to Embodiment 1 of the present invention results in stopping the calculation update of the estimated resistance in the speed region where the resistance estimation calculation cannot be stably performed. The speed observing means 5 and the resistance observing means 6 can calculate and output the estimated speed and the estimated resistance value, respectively, in a stable state even when the AC rotating machine 1 is rotating.

  In the above description, sig = 1 is set when ωr0 = 0 and sig = 0 when ωr0 ≠ 0 as shown in the equation (20) according to the characteristics of the transfer function illustrated in FIG. If stability is obtained in a certain speed range due to the characteristics of the transfer function, sig = 1 in the speed range, and sig = 0 in other speeds.

Embodiment 2. FIG.
In the first embodiment, the resistance observing means 6 can be operated so that the calculation of the estimated resistance value does not operate in an unstable manner regardless of the operating state of the AC rotating machine 1, but the estimated resistance value is calculated by the resistance estimation calculation. Can be updated only when the rotating machine is stopped. Therefore, the fluctuation of the armature resistance due to the temperature rise after the start of operation of the rotating machine is also reflected in the calculation of the estimated speed only when the rotating machine is stopped.
Therefore, the control apparatus for an AC rotary machine according to Embodiment 2 of the present invention provides resistance observation means that can always stably calculate an estimated resistance value regardless of the operating state of the rotary machine. .

  FIG. 8 is a diagram showing a configuration of a control device for an AC rotating machine according to Embodiment 2 of the present invention. The speed observing means 7 according to the second embodiment is the speed observing means 5 including the state observing unit 53 except that the estimated current vector is not output among the outputs of the speed observing means 5 according to the first embodiment. It is the same composition as. Other than the resistance observing means 8 is the same as that of the first embodiment, and the resistance observing means 8 will be mainly described below.

First, the reason why the resistance estimation becomes unstable during the rotation operation in the first embodiment will be described.
The transfer function in the case of calculating the resistance estimation in Expression (13) is shown. Here, since s * I4, AR, and C are fixed by the AC rotating machine, it is necessary to change the feedback gain of H in order to change the transfer function. Here, the feedback gain according to the Bode diagram shown in FIG. 3 is set to obtain the estimated speed stably, and is not an optimum gain for estimating the resistance.
Therefore, in the second embodiment, an adaptive observer in which an optimum feedback gain is set to estimate the resistance is created so that the estimated resistance value that does not become unstable depending on the speed can be calculated.

  An adaptive observer for calculating the estimated resistance value can be defined as in equations (21) to (24) when an observer for estimating the internal state of the AC rotating machine is configured on the dq axis. It should be noted that the calculation of the estimated resistance value from the equation (12) only needs to deal with the armature reaction and does not need to consider the rotor magnetic flux, so it is sufficient to calculate the estimated current vector, and the equations (21), (22) ), The calculation of the third and fourth lines of the determinant is omitted.

Next, the operation of the resistance observing means 8 will be described with reference to FIG. The resistance observing means 8 has the following configuration in order to calculate the equations (21) to (24).
The adder / subtractor 81 subtracts the detected current vector (ids, iqs) from the estimated current vector (Rids0, Riqs0) in resistance estimation, and outputs a current deviation vector (e3, e4). The matrix calculator 82 outputs a result obtained by multiplying the current deviation vector (e3, e4) ^T by the matrix H2. The estimated speed ωr0 input to the matrix calculator 82 is used to create the matrix H2, as will be described later.

  The design of the observer gain H2, for example, as shown in FIG. 10, when each gain is designed with a constant, as shown in the Bode diagram of FIG. 11, depending on the speed, the phase difference exceeds ± 90 degrees and is unstable. As shown in FIG. 12, by setting the observer gain to change the gain value according to the speed as shown in FIG. 12, the phase difference exceeds ± 90 degrees regardless of the speed as shown in FIG. There can be no stable transfer function designed.

The matrix calculator 83 outputs the result of multiplying the estimated value (Rφds0, Rφqs0) ^T of the armature reaction vector by the matrix AR. The estimated speed ωr0 and the estimated resistance value R0 input to the matrix calculator 83 are used to create the matrix AR (see Expression (23)).
The matrix calculator 84 outputs the result of multiplying the estimated speed ωr0 by the vector (0, φf) ^T.

The adder / subtracter 85 outputs a vector obtained by adding / subtracting the voltage command vector (vds, vqs) ^T , the output of the matrix calculator 82, the output of the matrix calculator 83, and the output of the matrix calculator 84.
The integrator 86 integrates the vector output from the adder / subtracter 85 for each element, and outputs a vector (Rφds0, Rφqs0) ^T. The above is the part corresponding to Equation (21). Note that the left side of Equation (21) corresponds to the input portion of the integrator 86.

The matrix calculator 87 multiplies the vector (Rφds0, Rφqs0) ^T by the matrix C3 to output an estimated current vector (Rids0, Riqs0) ^T. This part corresponds to Expression (22).
The estimated resistance calculator 88 calculates an estimated resistance value R0 from the estimated current vector (Rids0, Riqs0), the current deviation vector (e3, e4), and the estimated speed ωr0.

Hereinafter, the operation of the estimated resistance calculation unit 88 will be described with reference to FIG.
The estimated resistance calculator 88 includes an estimated resistance calculator 881 that calculates an estimated resistance value R0 from the current deviation vector (e3, e4) and the estimated current vector (Rids0, Riqs0) according to the equation (24), and an estimated resistance value. And an update determination unit 882 for determining whether to return to the speed observation means 7 as a true value.

Here, the operation of the update determination unit 882 will be described.
Expressions (21) to (24) showing the operation contents of the resistance observing means 8 of the second embodiment are based on the assumption that the estimated speeds are consistently matched. When an error occurs transiently in the estimated speed due to the effect of the response speed when a sudden speed change occurs, the error (e3, e4) is generated by the combination of Δω and ΔR as shown in the equation (25). To do. That is, if the estimated resistance value is calculated with the error (e3, e4) as an input, an error is generated by Δω. As described above, when an error occurs in the resistance value, the driving performance deteriorates.

  Therefore, the update determination unit 882 stores the estimated resistance value before the speed suddenly changes, and switches the output from the output of the estimated resistance computing unit 881 to the stored estimated resistance value when the speed suddenly changes. The estimated resistance value that sometimes includes an error is not output to the speed observation means 7.

  An estimated acceleration is calculated based on the estimated speed ωr0, a predetermined threshold value accelim is set for the estimated acceleration, and when the estimated acceleration exceeds the threshold value, the value of the estimated resistance value R0 output to the speed observation means 7 is sampled 1 Hold at previous value.

  Specifically, the estimated speed at the current sampling time is ωr0 [n], the output of the update determiner 882 is Rout [n], the estimated speed before sampling is ωr0 [n−1], and the update determiner 882 The output is Rout [n−1], the input of the update determination unit 882 is Rin, and the estimated resistance value R0 is updated under the condition of Expression (26).

  In these operations, the estimated speed ωr0 can be replaced with a speed command. Further, the acceleration threshold accelim set here may be determined in advance by performing a trial test with an actual machine, simulation, or the like, and determining an acceleration range in which the driving performance of the rotating machine does not deteriorate due to an error in resistance value.

  In the above, it can be considered that the resistance fluctuates during the operation of the AC rotating machine due to the temperature change. Further, since it may be considered that a sudden change in temperature at which the resistance value fluctuates suddenly does not occur, it may be considered that the resistance value fluctuates gradually during operation of the rotating machine. For this reason, the resistance observing means 8 can sufficiently estimate the resistance value that gradually changes even if the calculation cycle is lowered. Therefore, when mounting the resistance observing means 8 on the control device, there is no restriction such that the performance of an arithmetic processing device such as a microcomputer must be improved by the arithmetic load.

  As described above, the resistance observing means 8 of the control device for an AC rotary machine according to Embodiment 2 of the present invention is connected to the speed observing means 7 so as to ensure the stability of the transfer function in the calculation of the estimated resistance value. By calculating the estimated current using different observer gains H2 and estimating the resistance value based on the estimated current, the resistance value can always be stably calculated even during the rotational operation.

  Further, when an error occurs transiently in the estimated speed during sudden acceleration and an error occurs in the calculation of the estimated resistance, the update determination unit 882 stops the update of the estimated resistance value, so that the driving performance is reduced due to the resistance error. It can be prevented from lowering.

  In the second embodiment, unlike the first embodiment, in the velocity observation means 7 and the resistance observation means 8, both of the estimation calculations using the adaptive observer always ensure the stability. If the effect of some errors in the estimated resistance value due to the speed change is slight, the estimated resistance value R0 from the estimated resistance calculator 881 is always output except for the update determination unit 882 from the estimated resistance calculator 88. You may do it.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  The present invention relates to an AC rotating machine that can obtain the rotor position of an AC rotating machine having a saliency in the rotor and stator of an AC rotating machine, such as a permanent magnet motor or a synchronous reluctance motor, without using a position sensor. The present invention relates to a control device, and it is possible to improve the driving performance by estimating the fluctuation of the resistance value, which is a factor that lowers the driving performance, and can be widely used for controlling the AC rotating machine.

1 AC rotating machine, 2 current vector detection means, 3 control means, 4 voltage application means,
5, 7 Speed observation means, 6, 8 Resistance observation means, 53 State observation section,
63,88 estimated resistance calculator, 64 update determination unit, 881 estimated resistance calculator,
882 Update determiner.

Claims (2)

Control means for generating a voltage command based on a command from the upper control system, voltage applying means for applying a voltage to the AC rotating machine based on the voltage command, current detecting means for detecting a current of the AC rotating machine and outputting a detected current A speed observing means for calculating and outputting an estimated speed of the AC rotating machine using an adaptive observer based on the voltage command, the detected current and an estimated resistance value of the AC rotating machine, and the detected current and the estimated speed. In the control device for an AC rotating machine provided with resistance observation means for calculating and outputting the estimated resistance value based on
The speed observing means and the resistance observing means each include the estimated speed in a state where a necessary condition for the transfer function in each calculation to be stable is satisfied, including an observer gain set by the calculation using the adaptive observer. And calculating the estimated resistance value ,
The speed observation means calculates and outputs the estimated speed and the estimated current using an adaptive observer set to a first observer gain based on the voltage command, the detected current, and the estimated resistance value.
The resistance observing means is configured to calculate an estimated resistance value based on the detected current and the estimated current calculated by the speed observing means, and to determine whether or not the necessary condition is satisfied based on the estimated speed. And the control apparatus of the AC rotating machine provided with the update determination part which updates the output of the said estimation resistance calculating part only when the said required condition is satisfied . Control means for generating a voltage command based on a command from the upper control system, voltage applying means for applying a voltage to the AC rotating machine based on the voltage command, current detecting means for detecting a current of the AC rotating machine and outputting a detected current A speed observing means for calculating and outputting an estimated speed of the AC rotating machine using an adaptive observer based on the voltage command, the detected current and an estimated resistance value of the AC rotating machine, and the detected current and the estimated speed. In the control device for an AC rotating machine provided with resistance observation means for calculating and outputting the estimated resistance value based on
The speed observing means and the resistance observing means each include the estimated speed in a state where a necessary condition for the transfer function in each calculation to be stable is satisfied, including an observer gain set by the calculation using the adaptive observer. And calculating the estimated resistance value,
The speed observation means calculates and outputs the estimated speed using an adaptive observer set to a first observer gain based on the voltage command, the detected current, and the estimated resistance value.
The resistance observation means calculates and outputs the estimated resistance value using an adaptive observer set to a second observer gain based on the voltage command, the detected current, and the estimated speed,
Furthermore, the resistance observing means calculates an estimated acceleration based on the estimated speed, and the AC rotating machine includes an update determination unit that updates an output of the estimated resistance value only when the estimated acceleration is equal to or less than a predetermined set value . Control device.

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