JP5534991B2 - Control device for synchronous motor - Google Patents

Description

The present invention relates to a control equipment for controlling the rotational speed of the synchronous motor.

  In recent years, synchronous motors using permanent magnets (permanent magnet synchronous motors, PMSM) have been remarkably improved in performance, are small and highly efficient, and are used in all industrial fields including home appliances.

  A general PMSM has a rotating field structure in which a permanent magnet is provided on a rotor and an armature winding is provided on a stator. For PMSM control, it is necessary to detect the rotational angle position of the rotor. However, if a position sensor is used for this purpose, it is disadvantageous in terms of downsizing, noise resistance, and cost. Sensorless control without using a position sensor is performed.

  Various methods have been proposed for sensorless control of PMSM.

  That is, in Non-Patent Document 1, a PMSM stator coordinate system is used to construct a same-dimensional observer that estimates the current and rotating magnetic flux of the motor, and rotation is performed based on the difference between the estimated current value and the current value flowing through the actual motor. A technique for determining speed is disclosed.

  Non-Patent Document 2 discloses a dq-axis coordinate system in which the magnetic pole axis of a permanent magnet made by a PMSM rotor is d-axis and a q-axis advanced by π / 2 [rad] in electrical angle from the d-axis. A technique is disclosed in which a same-dimensional observer that estimates the electric current of the electric motor and the rotating magnetic flux is configured, and the rotational speed is obtained from the difference between the estimated current value and the current value flowing through the actual electric motor.

  Patent Document 1 discloses a control device using an observer that estimates an armature current based on a PMSM model.

JP 2009-95135 A

Saeko, Ritsuko Tomioka, Toru Nakano and Tokai Kin, “Position Sensorless Control of Brushless DC Motor with Adaptive Observer”, IEEJ Proceedings Vol. 113, No. 5, 1993 Yoshihiko Kanehara, “Position Sensorless Control of PM Motor Using Adaptive Observer on Rotating Coordinates” IEEJ Proceedings, Vol. 123, No. 5, 2003

  However, in the conventional method described above, in order to estimate the current and rotating magnetic flux of the synchronous motor, an observer of the same dimension in which the estimation variable is fourth order is configured, and the estimated current value and the actual motor Since the rotation speed is obtained from the difference from the current value flowing through the current, there is a problem that the total amount of calculation increases. Therefore, it is necessary to increase the processing speed of the arithmetic unit and to increase the storage capacity of the storage device.

  In addition, in order to operate the observer appropriately, the amount obtained by multiplying the difference between the electric current of the motor estimated by the observer and the actual current value by a certain value is adjusted, and the calculation for calculating the rotation speed is also appropriate. In order to make it operate | move, adjustment of the calculated value was required and there existed a problem that adjustment took time.

The present invention, when controlling the rotational speed of the synchronous motor without using a sensor, without using a conventional such observer, and an object thereof is to provide a equipment which can suppress the increase in the calculation amount.

An apparatus according to the present invention is a control device for controlling the rotational speed of a synchronous motor, and includes a speed adjusting unit that adjusts a speed based on a speed command, a current adjusting unit that adjusts a current, and the current adjusting unit. A non-interference control unit that performs non-interference control for removing interference based on the voltage command output from the rotation speed estimation value and a two-phase / coordinate conversion of the voltage output from the non-interference control unit A three-phase coordinate conversion unit, a power conversion unit for driving the current through the armature winding based on the output of the two-phase / three-phase coordinate conversion unit, and current detection for detecting the current flowing through the armature winding Unit, a three-phase / two-phase coordinate conversion unit that performs coordinate conversion of the current detected by the current detection unit, and a current target calculation that calculates a target value of current in a control model that eliminates interference based on the voltage command And the current detection unit A speed position estimating unit for obtaining an estimated value of the rotational speed and an estimated value of the magnetic pole position so that a difference between the generated current and the target value of the current calculated by the current target calculating unit is asymptotically zero. Yes, and the control model, the voltage-current equation is expressed by the following equation (1).

The speed position estimation unit is, for example,
Based on the following equation (2), an estimated value of the rotational speed and an estimated value of the magnetic pole position are obtained.

The present invention, when controlling the rotational speed of the synchronous motor without using a sensor, without using the conventional kind of observer may provide equipment which can suppress the increase in the calculation amount.

It is a block diagram which shows the example of a structure of the control apparatus of PMSM in this embodiment. It is an equivalent circuit of PMSM. It is a flowchart which shows the outline control content of the control apparatus in this embodiment. It is a block diagram which shows the example of a structure of the control apparatus of PMSM which is not sensorless. It is a block diagram which shows a nonlinear feedback system.

  FIG. 1 is a block diagram of PMSM sensorless non-interference vector control. FIG. 2 shows an equivalent circuit of PMSM.

  In FIG. 1, a PMSM (Permanent Magnet Synchronous Motor) is a rotating field type permanent magnet synchronous motor in which a rotor (rotor) is provided with a permanent magnet and a stator (stator) is provided with a three-phase armature winding. It is. The PMSM is driven to rotate at a rotational speed ω synchronized with the frequency by the three-phase AC power Pout that is frequency-controlled according to the speed command (rotational speed command) ω * and is output from the control device 1.

  That is, in the PMSM basic model, as shown in FIG. 2, the direction of the N pole of the permanent magnet is the d-axis, and the direction advanced by π / 2 from this is the q-axis. That is, the d axis and the q axis are model axes. The lead angle of the d-axis relative to the U-phase armature winding is defined as θ. That is, the d-axis-q-axis coordinate system is at a position advanced by an angle θ from the U-phase armature winding as a reference.

  Θ represents the actual angular position (magnetic pole position) of the magnetic pole with respect to the U-phase armature winding. The angular position θ can also be obtained by integrating the rotational speed ω.

  The γ-axis is determined in correspondence with the estimated angle θ ^ of the magnetic pole position with reference to the U-phase armature winding. A position advanced by π / 2 in electrical angle from the γ axis is the δ axis. That is, the γ-axis δ-axis coordinate system is at a position advanced by an angle θ ^ with respect to the U-phase armature winding. Further, the d-axis-q-axis coordinate system and the γ-axis-δ-axis coordinate system are extremely close to each other, and θ and θ ^ are substantially equal, and adaptive control is performed in the vicinity of the equilibrium point.

  The U-phase, V-phase, and W-phase armature windings each have a self-inductance L (Lu, Lv, Lw) including a leakage inductance l 'and an effective inductance L', and a winding resistance Ra.

  In this specification, the symbol “*” is used to indicate a command or a command value for each parameter, and the symbol “^” is used to indicate an estimated value or a calculated value for each parameter.

  The control device 1 includes a speed adjustment unit 11, a current adjustment unit 12 (12a, 12b), a non-interference control unit 13, a two-phase / three-phase coordinate conversion unit 14, a power conversion unit 15, a current detection unit 16, and a three-phase. / 2 phase coordinate conversion unit 17, current target calculation unit 18, and speed position estimation unit 19 are provided.

  The speed adjustment unit 11 performs speed adjustment based on a speed command (speed command value) ω *. That is, based on the difference (ω * −ω ^) between the speed command value ω * input from the outside and the speed estimated value ω ^ output from the speed position estimation unit 19, the δ-axis current command value iδ * is Calculate.

  That is, the speed adjustment unit 11 uses the difference (ω * −ω ^) between the speed command value ω * and the estimated speed value ω ^ as a deviation, and performs feedback control such as proportional / integral control (PI control) according to the speed command value. The δ-axis current command value (torque current command) iδ * is generated so that the rotation speed (actual rotation speed actual value) ω becomes (so that the deviation becomes zero).

  The current adjusters 12a and 12b perform current adjustment based on the γ-axis current command value iγ * or the δ-axis current command value iδ *, respectively. That is, the current adjustment unit 12a calculates the γ-axis voltage command value Vγ * based on the difference (iγ * −iγ) between the γ-axis current command value iγ * and the γ-axis current detection value iγ. The current adjusting unit 12b calculates the δ-axis voltage command value Vδ * based on the difference (iδ * −iδ) between the δ-axis current command value iδ * and the δ-axis current detection value iδ.

  In other words, the current adjusting units 12a and 12b use the differences (iγ * −iγ) and (iδ * −iδ) as deviations, respectively, so that the current values are equal to the command values by feedback control (the deviations become zero). ) To generate voltage commands Vγ * and Vδ * for the γ-axis or δ-axis.

  The non-interference control unit 13 uses the voltage command (γ-axis voltage command value Vγ *, δ-axis voltage command value Vδ *) output from the current adjustment unit 12 and the estimated rotational speed (speed estimated value ω ^). Based on this, non-interference control for removing the interference is performed. That is, the non-interference control unit 13 determines that the γ-axis voltage command value Vγ *, the δ-axis voltage command value Vδ *, the γ-axis current detection value iγ, the δ-axis current detection value iδ, and the speed estimation value ω ^ An axis voltage command value Vγ ** and a δ axis voltage command value Vδ ** are calculated. The γ-axis voltage command value Vγ ** and the δ-axis voltage command value Vδ ** output from the non-interference control unit 13 interfere with the input γ-axis voltage command value Vγ * and δ-axis voltage command value Vδ *. Minutes have been removed.

  In the non-interference control unit 13, the interference component is a voltage component (back electromotive force) ωL, −ωL, ωφm, etc. induced in the inductance L of the armature winding along with the rotation of the PMSM rotor. is there. The inductance L and the rotor magnetic flux φm can be obtained in advance, and the interference can be obtained from these and the estimated value (speed estimated value) ω ^ of the rotational speed.

  Non-interference control itself is a technique that has been used in the past. For example, Hidehiko Sugimoto, “Theory and Design of AC Servo Systems” (general electronic publisher, 1999/05/08, 77-80) Page).

  The two-phase / three-phase coordinate conversion unit 14 performs coordinate conversion of the voltage output from the non-interference control unit 13. That is, the γ-axis voltage command value Vγ ** and the δ-axis voltage command value Vδ ** from the non-interference control unit 13 are used to control the power conversion unit 15 in three-phase voltage command values u, v, and w. Convert to

  The power conversion unit 15 includes a PWM control unit and an inverter. The power conversion unit 15 generates a PWM (Pulse Width Modulation) signal based on the output from the 2-phase / 3-phase coordinate conversion unit 14, and applies the PWM signal to each gate of the switching element of the inverter. The inverter outputs a three-phase AC power Pout with a controlled frequency and amplitude. This causes a three-phase current to flow through the PMSM u, v, and w armature windings, and the rotor is driven to rotate in synchronization therewith. The

  The current detector 16 detects a current flowing through the armature winding of the PMSM. That is, the actual current (current detection value) flowing through the PMSM is detected. In FIG. 1, the currents iu, iv, and iw flowing in the u, v, and w phases are detected. However, only one of the two phases may be detected, and the remaining one phase may be obtained by calculation. Good.

  The three-phase / two-phase coordinate conversion unit 17 performs coordinate conversion of the current detected by the current detection unit 16. That is, the three-phase currents iu, iv, iw from the current detector 16 are converted into a current iγ in the γ-axis direction and a current iδ in the δ-axis direction in the γ-δ axis coordinate system. Although the currents i γ and i δ are converted, they correspond to the current that actually flows through the PMSM, and are also current detection values. Therefore, it may be described as “current detection values iγ, iδ”.

  Based on the γ-axis voltage command value Vγ * and the δ-axis voltage command value Vδ * output from the current adjustment unit 12, the current target calculation unit 18 calculates a target value of current in the control model from which the interference is removed. In other words, the current target calculation unit 18 eliminates the influence of the counter electromotive force proportional to the rotational speed ω of the PMSM based on the γ-axis voltage command value Vγ * and the δ-axis voltage command value Vδ *. In the circuit, id ^ and iq ^, which are d-axis and q-axis current target values, are calculated.

  The current target values id ^ and iq ^ are target values in an ideal control model from which interference has been removed, and are estimated by calculation in the current target calculation unit 18 and are therefore referred to as "current estimated values". Can do. Therefore, it may be described as “current estimation value id ^, iq ^”.

  The current target calculation unit 18 obtains a target value for adaptive control in an ideal control model (adaptive model) from which interference is removed, and the current target calculation unit 18 defines an adaptive model. Therefore, the current target calculation unit 18 can also be referred to as the “adaptive model unit 18”.

  The speed position estimator 19 compares the difference between the currents iγ and iδ detected by the current detector 16 and the target values id ^ and iq ^ calculated by the current target calculator 18 (id ^ -iγ), ( The estimated value of rotational speed (speed estimated value) ω ^ and the estimated value of magnetic pole position (magnetic pole estimated value) θ ^ are determined so that both iq ^ -iδ) become asymptotically zero.

  In the γ-δ axis coordinate system, the magnetic pole axis of the PMSM estimated by the velocity position estimation unit 19 is the γ axis, and the axis advanced by π / 2 in electrical angle from the γ axis is the δ axis.

  The estimated speed value ω ^ obtained by the speed position estimating unit 19 is used in the calculation of the δ-axis current command value iδ * in the speed adjusting unit 11. The estimated value θ ^ of the magnetic pole position is used for coordinate conversion in the two-phase / three-phase coordinate conversion unit 14.

  The current target calculation unit 18 and the speed position estimation unit 19 perform adaptive control based on the detected current values iγ and iδ and the voltage command values Vγ * and Vδ * so that the current error in the control model becomes asymptotically zero. These are performed, and these constitute the adaptive control unit TS.

  The adaptive control unit TS performs adaptive control so that the error is asymptotically zero. However, when the error is asymptotically zero, there is a sudden change so that the control is not disturbed. It means that control is done to avoid as much as possible.

  In the control device 1 of the present embodiment, a simple current circuit model of PMSM called an adaptive model is used. From the difference between the current value estimated in the adaptive model and the current value actually flowing through the PMSM, the rotational speed and the magnetic pole position are calculated. Is estimated. Control is performed using the estimated speed estimated value ω ^ and magnetic pole estimated value θ ^ instead of the detection values obtained by the position sensor and speed sensor conventionally used.

  Therefore, the adaptive model used in the current target calculation unit 18 can show the voltage-current equation by the following equation (7).

  Moreover, the speed position estimation part 19 can obtain | require speed estimated value (omega) ^ and magnetic pole estimated value (theta) ^ based on following (8) Formula.

  Moreover, the speed position estimation part 19 can also obtain | require speed estimated value (omega) ^ and magnetic pole estimated value (theta) ^ based on following (9) Formula.

  When the speed position estimation unit 19 uses the above equation (8) or (9), the non-interference control unit 13 performs non-interference control based on equation (16) described later.

  Moreover, the speed position estimation part 19 can also obtain | require speed estimated value (omega) ^ and magnetic pole estimated value (theta) ^ based on following (10) Formula.

  When the speed position estimation unit 19 uses the above equation (10), the non-interference control unit 13 performs non-interference control based on the following equation (11).

  In the control device 1 of the present embodiment, as shown in the flowchart of FIG. 3, the currents iγ and iδ flowing through the armature winding of the PMSM are detected (# 11), and interference is performed based on the voltage commands Vγ * and Vδ *. The current target values id ^ and iq ^ in the control model with the minutes removed are calculated (# 12), and the difference between the calculated current target value and the detected current values iγ and iδ (id ^ -iγ), (iq The estimated rotational speed value ω ^ and the estimated magnetic pole position θ ^ are obtained so that (^ -iδ) becomes asymptotically zero (# 13), and the obtained estimated rotational speed value ω ^ and the estimated magnetic pole position are obtained. Based on the value θ ^, speed control and coordinate conversion are performed (# 14).

  In the control device 1 of this embodiment, a simple PMSM current circuit model called an adaptive model is used, and the rotational speed and the magnetic pole position are calculated from the difference between the current value estimated in the adaptive model and the current value actually flowing through the PMSM. Since only the estimation is performed, the calculation amount can be suppressed without increasing so much, and the adjustment is easy.

  Next, the control device 1 will be described in more detail.

  FIG. 4 is a block diagram of a control device 80 that uses a position sensor, that is, is not sensorless, without using the current target calculation unit 18 and the speed position estimation unit 19 for comparison with the control device 1 of the present embodiment. It is shown.

  4, the control device 80 includes a speed adjustment unit 81, current adjustment units 82a and 82b, a non-interference control unit 83, a two-phase / three-phase coordinate conversion unit 84, a power conversion unit 85, a current detection unit 86, and a three-phase / A two-phase coordinate converter 87, a position detector 88, and a speed detector 89 are provided.

  With the magnetic pole axis of the PMSM rotor as the d axis, the voltage / current equation in the dq axis coordinate system can be expressed by the following equation (12).

  The equation (12) above can be expressed by the following equation (13) with the voltage value as the input variable and the current value as the state variable.

  That is, the actual currents (current detection values) id and iq of the d-axis and q-axis are when the current flows even if the d-axis voltage value Vd and the q-axis voltage value Vq that are input voltages do not change. When the rotor rotates, it is affected by the counter electromotive force proportional to the rotational speed ω of the rotor.

  That is, the actual d-axis current id and q-axis current iq are subject to interference by the counter electromotive force generated by the rotor, which causes deterioration of the current response of the PMSM. In order to eliminate such interference, non-interference control for removing the interference is conventionally performed.

  Therefore, the non-interference control unit 83 performs the calculation shown in the following equation (14).

  That is, the non-interference control unit 83 generates a voltage command value having positive and negative back electromotive force components proportional to the rotational speed ω, thereby canceling the influence of the back electromotive force. Thereby, non-interference control is performed.

  As a result, a state equation in which the voltage commands Vq * and Vd * output from the current adjustment unit 82 are input variables and the current values id and iq are state variables can be expressed by the following equation (15).

  As shown by the above equation (15), the counter electromotive forces ωL, −ωL, and ωφm proportional to the rotational speed ω are eliminated, and the dq axis non-interference control is realized.

  Returning to FIG. 1, since the control device 1 of the present embodiment performs non-interference control without a sensor, the non-interference control unit 13 is output from the speed position estimation unit 19 instead of the actual rotational speed ω. The following equation (16) is calculated with the estimated rotational speed value ω ^ as an input.

  The δ-axis voltage command value Vδ ** and the γ-axis voltage command value Vγ ** output from the non-interference control unit 13 are input to the 2-phase / 3-phase coordinate conversion unit 14, and the 2-phase / 3-phase coordinate conversion unit 14 The magnetic pole position estimated value θ ^ output from the speed position estimating unit 19 is used to convert it into a three-phase AC voltage command value. The power converter 15 outputs the three-phase AC power Pout according to the voltage command value output from the two-phase / three-phase coordinate converter 14, whereby an actual voltage is applied to the PMSM.

  The current that actually flows through the armature winding of the PMSM is detected by the current detection unit 16 and input to the three-phase / two-phase coordinate conversion unit 17. In the three-phase / two-phase coordinate conversion unit 17, the estimated value θ ^ of the magnetic pole position output from the velocity position estimation unit 19 is used to convert the detected values iγ and iδ of the two-phase DC currents of the γ-axis and δ-axis. Is done.

  The current target calculation unit 18 uses the γ-axis voltage command Vγ * and the δ-axis voltage command Vδ * output from the current adjustment unit 12 as input values and removes the influence of the counter electromotive force proportional to the rotational speed ω. The following equation (17) on the γ-axis and δ-axis in the above equation (15), which is the state equation of the current circuit of the PMSM, is calculated.

  The current target calculation unit 18 outputs the d-axis and q-axis current estimation values id ^ and iq ^ by the calculation of the above equation (17).

  The speed position estimator 19 includes the d-axis and q-axis current estimated values id ^ and iq ^ output from the current target calculator 18, the actual current values iδ output from the three-phase / two-phase coordinate converter 17, Based on iγ, the rotational speed ω ^ and the magnetic pole position θ ^ are estimated.

  One example for realizing the speed position estimation unit 19 is expressed by the above-described equation (8). That is, the rotational speed ω ^ is determined from the deviation between the d-axis and q-axis current estimation values id ^ and iq ^ from the current target calculation unit 18 and the current values iδ and iγ from the three-phase / two-phase coordinate conversion unit 17. presume. The magnetic pole position θ ^ is obtained by integrating the estimated rotational speed ω ^, and this is used as the estimated value of the magnetic pole position.

  Another example for realizing the speed position estimating unit 19 is expressed by the above-described equation (9). That is, the rotational speed ω ^ is determined from the deviation between the d-axis and q-axis current estimation values id ^ and iq ^ from the current target calculation unit 18 and the current values iδ and iγ from the three-phase / two-phase coordinate conversion unit 17. presume.

  In this case, “sgnω ^” indicating the rotational direction of the estimated rotational speed ω ^ is replaced by “ω ^”.

  Still another example for realizing the speed position estimating unit 19 is expressed by the above-described equation (10). That is, the rotational speed ω ^ is determined from the deviation between the d-axis and q-axis current estimation values id ^ and iq ^ from the current target calculation unit 18 and the current values iδ and iγ from the three-phase / two-phase coordinate conversion unit 17. presume.

  In this case, “sgnω ^” indicating the rotation direction of the estimated rotational speed ω ^ is “sin (θ−θ ^)”, which is a sine of an angular deviation (θ−θ ^) between the d axis and the γ axis. Has been replaced. In this case, the non-interference control unit 13 calculates the expression (11) instead of the expression (16) described above.

  The control device 1 of the present embodiment includes one or more CPUs or DSPs, ROM, RAM, peripheral circuit elements, interface circuit elements, logic circuit elements, switching circuit elements, IC circuit elements, other semiconductor elements, passive It can be configured using circuit elements, various electronic devices, electronic components, and the like. The operations described above can be realized by software executed by a CPU or DSP, hardware such as a logic circuit, or a combination of these programs stored in a memory.

  As described above, according to the control device 1 of the present embodiment, when controlling the rotational speed of the PMSM without using a sensor, an increase in the amount of calculation can be suppressed without using a conventional observer.

The adaptive control by the control device 1 will be further described.
[PMSM sensorless control method based on model reference adaptive system]
In PMSM sensorless control, the accuracy of PMSM model parameters strongly affects the accuracy and performance of magnetic pole position estimation. There is an adaptive system as a control technique for actively making the system robust while following and identifying parameter variations. It has already been confirmed that the model reference adaptive system (MRAS) is effective for identifying the moment of inertia of the load. ). Here, we propose a method for constructing MRAS with unknown parameters such as resistance, reactor, and field constant, and realizing PMSM magnetic pole position sensorless control with rotational speed as an unknown parameter. In the following description, the derivation of the adaptive identification algorithm is shown.

  An adaptive identification algorithm for the magnetic pole position will be described.

  First, the voltage-current equation on the dsq rotation coordinate of PMSM is shown in equation (18).

  FIG. 1 shows the configuration of the model reference adaptive identification system studied here. Here, the speed is estimated by assuming that the actual speed is constant, but if the internal model principle is applied to the adaptive identification rule of the estimation system, the error of speed estimation can be reduced even in an excessive state where the speed fluctuates. It is.

  In sensorless control of PMSM, there are a method based on an adaptive observer, a method using an extended induced voltage, and the like for medium and high speed regions. However, most of these methods use a mathematical model of the motor, and the performance of sensorless control is affected by the accuracy of the parameters used. For this reason, research on measurement techniques of various parameters during stoppage and operation is active.

  Focusing on this point, a magnetic pole position sensorless control method based on a model reference adaptive system (MRAS) that can be extended to parameter identification is proposed. First, the configuration of non-interference sensorless control based on MRAS in the current control loop will be described. Next, the derivation of the reference model for magnetic pole position identification, the proof of stability, and the derivation of the identification rule are described.

  Next, the configuration of MRAS will be described.

  In PMSM position / velocity control, vector control is generally used, and non-interference control is used in order to eliminate the influence of velocity electromotive force between dq rotation coordinates. The configuration of the magnetic pole position sensorless control system proposed here is shown in FIG. As is apparent from the figure, this is a structure in which an adaptive model and a velocity / position estimation block, which are elements of MRAS, are added to the conventional PMSM non-interference vector control system, and the estimated rotational coordinates (γ− It is characterized in that the MRAS is configured on the δ axis) and in a current control loop to which non-interference control is added. The adaptive model is a non-interfering PMSM ideal current circuit model, and the speed / position estimation is to estimate the magnetic pole position / rotation speed from the generated model currents id ^, iq ^ and the detected actual currents iγ, iδ. .

Next, adaptive identification of the magnetic pole position will be described.
(Equation of state at γ-δ rotation axis)
The voltage-current equation on the dsq rotation coordinate of PMSM is shown in the above equation (18).

  When the above equation (18) is modified to obtain a state equation in the dq coordinate of PMSM using current as a state variable and output variable and voltage as an input variable, the following equation (19) is obtained.

  On the other hand, when the state equation on the γ-δ estimated rotation coordinate is obtained, the following equation (20) is obtained.

(Non-interference control and adaptive model)
In the above equation (19), there are velocity electromotive force terms that interfere with each other on the d-axis and the q-axis.

  When the interference term is removed by performing non-interference control by the above equation (21) and the obtained equation is a reference model, the following equation (22) is obtained.

  After performing non-interference control on the equation (20a) of the estimated rotational coordinate (γ-δ axis), a control law (voltage input) to be applied to the PMSM is obtained from a deterministic equivalent principle (CE principle).

  When the above equation (23) is substituted into the equation (20a), the following equation (24) including the induced voltage on the estimated rotational coordinate (γ-δ axis) and the estimated induced voltage can be obtained.

(Error equation)
Errors εγ and εδ between the reference model and actual values are defined by the following equation (25).

  From the above equations (22) and (24), an error equation is obtained in which parameters such as resistance, reactor, and induced voltage constant are known and only the rotational speed is an unknown parameter. From equation (22) to equation (24),

  It becomes. Induced voltage on the estimated axis in equation (26) above

Can be approximated as in the following equation (28).

The above equations (28a) and (28b) and the following equation (29):

Is substituted into the above equation (26),

  In the above equation (30), the MRAS is configured so that the deviation between the magnetic pole position and the rotation speed becomes zero, that is, θ−θ ^ → 0 and ω−ω ^ → 0. If the magnetic pole position is θ−θ ^ → 0, the rotation speed will be ω−ω ^ → 0, so the rotation speed deviation ω−ω ^ in equation (30) is replaced with | ω | (θ−θ ^) Discussing sex does not cause problems. Therefore, the error equation is the following equation (31) obtained by modifying equation (30).

(Stability and adaptation law)
MRAS is non-linear and proves stability based on Popov's theory of superstability. Here, although the proof that the speed position estimation unit 19 uses the above equation (8) is proved, the speed position estimation unit 19 uses the above equation (9) or (10). Can be proved in the same way by transforming the equation.

  FIG. 5 shows a non-linear feedback system. In the above equation (31),

After all,

It becomes. Expression (33) can be transformed into a function of input u and output e, and corresponds to the linear stationary block transfer function G (s) in FIG. In Equation (33), since the matrix A is an asymptotically stable matrix, G (s) is strongly positive and satisfies Popov's first condition. Furthermore, in order for the feedback system of FIG. 5 to be stable, it is necessary to satisfy Popov's integral inequality (45), which is the second condition.

  Since w = −u in the above equation (32),

  Substituting the following equation (35) into equation (34),

It becomes. Assuming that the rotational speed ω is constant, the magnetic pole position θ becomes a linear function (1 / s ² ) of t. Therefore, in order to prevent a steady deviation from occurring in the estimated value of θ from the internal model principle, the adaptive law is 1 / s ² It is necessary to include the ingredients. The adaptation law of ω-ω ^

And the proportional + integral of the above equation (37) is integrated,

Is an adaptive law of magnetic pole position error. From equation (39) above,

From the above equations (36), (38), and (40),

Is obtained. Therefore, the following equation (42) can be proved by a simple calculation,

Since Ms. Popov's integral inequality (34) is satisfied, MRAS becomes asymptotically stable, and the error converges to 0 as in the following equation (43).

  From the above, the actual adaptive law of the estimated magnetic pole position θ ^ and the estimated rotation speed ω ^ assumes that ω is constant, and the rotation direction of ω and ω ^ is the same, so the polarity of ω ^ (rotation direction) is used. By

It becomes.
[Musubi]
As described above, in the control device 1 of the present embodiment, the difference between the ideal model (normative model) and the actually measured value is obtained, and the deviations εγ (= id ^ -iγ), εδ (= iq ^ -iδ) , Εδ−εγsgnω ^ is obtained so that the estimated rotational speed ω ^ is stably zero. According to such control, high-speed control can be performed with a small amount of calculation.

  In the control device 1 described above, the speed adjustment unit 11 performs the proportional / integral control (PI control) so that the deviation (ω * −ω ^) becomes zero. PID control) and other controls may be performed. The speed adjusting unit 11 may obtain a torque command value and obtain current command values iγ * and iδ * for obtaining the torque. Deviations (iγ * −iγ) from the detected current values iγ and iδ output from the three-phase / two-phase coordinate conversion unit 17 using the current command values iγ * and iδ * output from the speed adjusting unit 11 ( i δ * −i δ) may be calculated and input to the current adjusting units 12a and 12b.

  In addition, PMSM, current adjustment unit 12, non-interference control unit 13, current target calculation unit 18, speed position estimation unit 19, or each part or entire configuration of control device 1, structure, circuit, shape, method, number, calculation contents The processing content, processing order, and the like can be changed as appropriate in accordance with the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 Control apparatus 11 Speed adjustment part 12 Current adjustment part 13 Non-interference control part 14 2-phase / 3-phase coordinate conversion part 15 Power conversion part 16 Current detection part 17 3-phase / 2-phase coordinate conversion part 18 Current target calculation part 19 Speed position Estimator ω * rotational speed command value ω ^ rotational speed estimated value ω rotational speed actual value θ ^ estimated magnetic pole position θ magnetic pole position actual value iγ * γ-axis current command value iδ * δ-axis current command value iγ γ-axis current actual value iδ δ-axis current actual value id ^ d-axis estimated current value iq ^ q-axis estimated current value Vγ * γ-axis current adjuster command value Vδ * δ-axis current adjuster command value Vγ ** γ-axis voltage command value Vδ ** δ-axis voltage command value

Claims (5)

A control device for controlling the rotational speed of the synchronous motor,
A speed adjusting unit for adjusting the speed based on the speed command;
A current adjustment unit for current adjustment;
A non-interference control unit that performs non-interference control to remove interference based on the voltage command output from the current adjustment unit and the estimated value of the rotation speed;
A two-phase / three-phase coordinate conversion unit for converting the voltage output from the non-interference control unit;
A power converter for driving the armature winding based on the output of the two-phase / three-phase coordinate converter;
A current detector for detecting a current flowing in the armature winding;
A three-phase / two-phase coordinate conversion unit that converts the current detected by the current detection unit;
A current target calculation unit for calculating a target value of a current in a control model from which interference is removed based on the voltage command;
Speed position for obtaining the estimated value of the rotational speed and the estimated value of the magnetic pole position so that the difference between the current detected by the current detector and the target value of the current calculated by the current target calculator is asymptotically zero. an estimation unit, the possess,
The control model is
The voltage-current equation is expressed by the following equation (1):

The speed position estimation unit
Based on the following equation (2), an estimated value of the rotational speed and an estimated value of the magnetic pole position are obtained.

The control apparatus of the synchronous motor characterized by the above-mentioned. A control device for controlling the rotational speed of the synchronous motor,
A speed adjusting unit for adjusting the speed based on the speed command;
A current adjustment unit for current adjustment;
A non-interference control unit that performs non-interference control to remove interference based on the voltage command output from the current adjustment unit and the estimated value of the rotation speed;
A two-phase / three-phase coordinate conversion unit for converting the voltage output from the non-interference control unit;
A power converter for driving the armature winding based on the output of the two-phase / three-phase coordinate converter;
A current detector for detecting a current flowing in the armature winding;
A three-phase / two-phase coordinate conversion unit that converts the current detected by the current detection unit;
A current target calculation unit for calculating a target value of a current in a control model from which interference is removed based on the voltage command;
Speed position for obtaining the estimated value of the rotational speed and the estimated value of the magnetic pole position so that the difference between the current detected by the current detector and the target value of the current calculated by the current target calculator is asymptotically zero. an estimation unit, the possess,
The control model is
The voltage-current equation is expressed by the following equation (1):

The speed position estimation unit
Based on the following equation (3), an estimated value of the rotational speed and an estimated value of the magnetic pole position are obtained.

The control apparatus of the synchronous motor characterized by the above-mentioned. A control device for controlling the rotational speed of the synchronous motor,
A speed adjusting unit for adjusting the speed based on the speed command;
A current adjustment unit for current adjustment;
A non-interference control unit that performs non-interference control to remove interference based on the voltage command output from the current adjustment unit and the estimated value of the rotation speed;
A two-phase / three-phase coordinate conversion unit for converting the voltage output from the non-interference control unit;
A power converter for driving the armature winding based on the output of the two-phase / three-phase coordinate converter;
A current detector for detecting a current flowing in the armature winding;
A three-phase / two-phase coordinate conversion unit that converts the current detected by the current detection unit;
A current target calculation unit for calculating a target value of a current in a control model from which interference is removed based on the voltage command;
Speed position for obtaining the estimated value of the rotational speed and the estimated value of the magnetic pole position so that the difference between the current detected by the current detector and the target value of the current calculated by the current target calculator is asymptotically zero. an estimation unit, the possess,
The control model is
The voltage-current equation is expressed by the following equation (1):

The speed position estimation unit
Based on the following equation (4), an estimated value of the rotational speed and an estimated value of the magnetic pole position are obtained.

The control apparatus of the synchronous motor characterized by the above-mentioned. The non-interference control unit is
Perform non-interference control based on the following equation (5).

The control apparatus for a synchronous motor according to claim 1 or 2 . The non-interference control unit is
Non-interference control is performed based on the following equation (6).

The control apparatus for a synchronous motor according to claim 3 .

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