JP2010041868A - Rotor rotation monitor for synchronous motor, and control system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To monitor the state of rotation move of the rotor of a synchronous motor easily, using a simple method under specified conditions. <P>SOLUTION: A rotor rotation monitor includes current detecting means 4 and 5, which detect a current flowing through an armature coil of a synchronous motor 1; a voltage instruction value determining means 15, which determines a target value for an applied voltage to the armature coil so as to make a deflection between a target value for the current flowing through the armature coil and a current detection value converge to zero; a voltage applying means 3 which applies a voltage to the armature coil in accordance with a determined voltage instruction value, and monitoring means 13, 14, 23 and 25, which keep a current instruction value input to the voltage instruction value determining means 15 at 0, under the condition of being predetermined as the condition for monitoring the state of rotation movement of the rotor of the motor 1, and monitor the state of rotation move of the rotor based on a voltage instruction value determined by the voltage instruction value determining means 15 under the condition of keeping the current instruction value at 0. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a rotor rotation monitoring device that monitors a rotational motion state of a rotor of a synchronous motor, and a control system including the rotor rotation monitoring device.

  In a synchronous motor (PMSM: Permanent Magnet Synchronous Motor) with a permanent magnet in the rotor, the rotor magnetic pole position (rotational angle position of the magnetic pole) with respect to the stator is sequentially determined in order to perform operations that require control of the output torque and rotational speed. Need to recognize. In this case, a magnetic pole position sensor represented by a resolver, a rotary encoder, a hall element, etc. is used to detect the magnetic pole position of the rotor, and a so-called sensorless control technique is used without using the magnetic pole position sensor. In some cases, the magnetic pole position of the rotor is estimated by the estimation calculation process. As a technique for estimating the magnetic pole position of the rotor of a synchronous motor (hereinafter sometimes simply referred to as “motor”) by sensorless control, for example, techniques disclosed in Patent Document 1 and Non-Patent Document 1 are generally known.

  In the present specification, “sensorless control” is used to mean that the magnetic pole position of the rotor is estimated without a hardware sensor that detects the magnetic pole position of the rotor.

  The technique found in Patent Document 1 is that a magnetic pole of a rotor that is stopped while applying a pulse voltage to the armature winding of the motor by a method using a state equation in a state where the rotation of the rotor of the motor is stopped. The position is to be estimated.

Further, in the technique shown in Non-Patent Document 1, when the rotation speed of the rotor of the motor is in the middle / high speed range, the magnetic pole position of the rotor is estimated by a method using the induced voltage of the motor. Further, when the rotational speed of the rotor of the electric motor is in a low speed range, the magnetic pole position of the rotor is estimated by a method using the inductance of the electric motor.
Japanese Patent No. 3282657 Takaharu Takeshita and three others, “Sensorless salient pole type PM synchronous motor control in all speed range”, The Institute of Electrical Engineers of Japan, 2000, Electrotechnical D, Vol. 120, No. 2, p. 240-247

  By the way, in an electric motor control system including a magnetic pole position sensor, when the magnetic pole position sensor fails, the magnetic pole position indicated by the output of the magnetic pole position sensor becomes abnormal. For this reason, the magnetic pole position of the rotor and the rotational speed of the rotor cannot be properly grasped, and the desired operation of the electric motor cannot be performed.

  In the sensorless control system, it may be difficult to stably operate the motor due to, for example, an estimation error of the magnetic pole position.

  Therefore, when the occurrence of an abnormality in the magnetic pole position detected by the magnetic pole position sensor or the magnetic pole position estimated by sensorless control is detected, processing corresponding to the occurrence of the abnormality, such as temporarily stopping the operation of the control system, is performed. There is a need to do.

  However, in this case, since the rotational speed of the rotor of the electric motor cannot be properly grasped, a drive circuit such as an inverter circuit that applies a voltage to the armature winding of the electric motor while the rotor is still rotating. There is a risk of interrupting the supply of the power source power (turning off the switch between the drive circuit and the power source). In such a case, an induced voltage generated in the armature winding of the motor due to the rotation of the rotor of the motor is applied to the drive circuit, which may cause damage to the drive circuit.

  Therefore, when an abnormality occurs in the magnetic pole position detected by the magnetic pole position sensor or the magnetic pole position estimated by sensorless control, it is desired to monitor the rotational motion state of the rotor of the motor by some method. .

  In addition, in the sensorless control system, when starting the operation of the motor, the rotor of the motor has already been rotated by the external force applied from the load side of the motor before starting the estimation of the magnetic pole position by the sensorless control method. There may be. For example, in an electric motor that drives a fan, the rotor of the electric motor may already be rotating before the operation of the electric motor is started due to the influence of wind or the like.

  As described above, if the rotor of the motor is rotating before the operation of the motor is started, the conventional sensorless control system causes the following inconvenience.

  That is, for example, in the technique disclosed in Patent Document 1, since the magnetic pole position is estimated using the state equation in a state where the rotor is stopped, the rotor has already been operated before the start of operation of the electric motor. If it is rotating, the magnetic pole position cannot be estimated properly. Further, in the technique shown in Non-Patent Document 1, when the rotor is already rotating before the operation of the electric motor is started, it is not possible to know how much the rotation speed is, so a method using an induced voltage. It is not possible to determine which of the methods using the inductance and the method using the inductance should estimate the magnetic pole position of the rotor. In this case, if the motor operation is started while estimating the magnetic pole position of the rotor by any one of the methods, the reliability of the estimated value of the magnetic pole position depends on the rotational speed of the rotor before the operation is started. Therefore, it is difficult to perform a desired operation of the electric motor.

  Therefore, it has been desired to grasp the rotational motion state of the rotor of the electric motor by some method before starting the operation of the electric motor.

  As described above, it has been desired to monitor the rotational motion state of the rotor of the motor under a predetermined situation in any of the motor control system including the magnetic pole position sensor and the sensorless control system.

  The present invention has been made in view of such a background, and an object of the present invention is to provide a rotor rotation monitoring device capable of easily monitoring the rotational motion state of a rotor of a synchronous motor by a simple method under a predetermined situation. And It is another object of the present invention to provide a control system that can appropriately perform processing when an abnormality of a detected value or estimated value of a magnetic pole position occurs using this rotor rotation monitoring device. It is another object of the present invention to provide a control system capable of appropriately starting operation of an electric motor in a sensorless control system using the rotor rotation monitoring device.

  In order to achieve the above object, a rotor rotation monitoring device for a synchronous motor according to the present invention is a device for monitoring the rotational motion state of a rotor in a synchronous motor having a permanent magnet in the rotor, and the armature of the synchronous motor Current detection means for detecting a current flowing through the winding, a current command value that is a target value of the current of the armature winding, and a current detection value of the armature winding indicated by the output of the current detection means are input. A voltage command value determining means for determining a voltage command value that is a target value of a voltage to be applied to the armature winding so that a deviation between the current command value and the detected current value converges to “0”; Voltage application means for applying a voltage to the armature winding in accordance with the determined voltage command value, and the voltage command value determination means under a situation predetermined as a situation in which the rotational motion state of the rotor should be monitored Enter in Monitoring means for monitoring the rotational motion state of the rotor based on a monitoring voltage command value that is a voltage command value determined by the voltage command value determining means in the held state. (First invention).

  According to the first aspect of the invention, the monitoring means holds the current command value input to the voltage command value determining means at “0” under the situation where the rotational motion state of the rotor is to be monitored. Therefore, the voltage command value determining means determines the voltage command value so that the current flowing through the armature winding of the synchronous motor is kept at “0”. And according to this voltage command value, since a voltage is applied to the armature winding, no current flows through the armature winding of the motor.

  Here, the state in which voltage is applied to the armature winding so that current does not flow through the armature winding of the motor while the rotor of the motor is rotating is applied to the armature winding by rotation of the rotor. In this state, a voltage that cancels the generated induced voltage is applied to the armature winding. Therefore, in this state, the voltage command value determined by the voltage command value determining means depends on the actual rotational speed of the rotor. More specifically, there is a proportional relationship between the magnitude of the applied voltage of the armature winding defined by the voltage command value in the state where the current of the armature winding is “0” and the rotational speed of the rotor. Will be established.

  Therefore, in the first invention, the monitoring means has a voltage command value determined by the voltage command value determining means in a state where the current command value is held at “0”, that is, a current flowing through the armature winding is “0”. The voltage command value determined so as to be held at is used as the monitoring voltage command value, and the rotational motion state of the rotor is monitored based on the monitoring voltage command value. In this case, the monitoring voltage command value depends on the rotational speed of the rotor of the electric motor. Therefore, the rotational motion state of the rotor can be properly grasped based on the monitoring voltage command value.

  Thus, according to the first aspect of the present invention, the voltage command value is set so that the current flowing through the armature winding of the motor is maintained at “0” under the situation where the rotational motion state of the rotor of the synchronous motor is to be monitored. The rotational motion state of the rotor can be appropriately grasped based on the voltage command value only by executing a simple process of determining and applying a voltage to the armature winding according to the voltage command value. It becomes.

  Therefore, according to the first invention, the rotational motion state of the rotor of the synchronous motor can be easily monitored by a simple method under a predetermined situation.

  In the first invention, speed estimation means for estimating the electrical angular speed of the rotor from the monitoring voltage command value, and integration for obtaining an integral value of the electrical angular speed estimated by the speed estimation means as a magnetic pole position estimation value of the rotor. And the voltage command value determination means performs vector control using the magnetic pole position estimation value obtained by the integration means in a state where the current command value is held at “0” by the monitoring means. It is preferable to determine the voltage command value by executing a calculation process (second invention).

  That is, since the monitoring voltage command value depends on the rotational speed of the rotor of the electric motor as described above, the electrical angular velocity of the rotor can be estimated from the monitoring voltage command value by the speed estimation means. The rotor magnetic pole position estimation value (rotor rotation angle) as an integration value obtained by integrating the estimated electrical angular velocity by the integration means changes at the same period as the rotation period of the rotor. . As a result, the estimated value of the magnetic pole position changes in synchronization with the induced voltage generated in the armature winding as the rotor rotates. For this reason, the magnetic pole position is calculated by executing a vector control calculation process using the magnetic pole position estimated value obtained by the integrating means in a state where the current command value is held at “0” by the monitoring means. Even if the estimated value has an error with respect to the actual magnetic pole position, the voltage command value is determined so that the current flowing through the armature winding smoothly and quickly converges to “0”. .

  For this reason, the current of the armature winding can be quickly converged to “0” while suppressing frequent fluctuations in the current of the armature winding. That is, it is possible to quickly realize a state where the rotational motion state of the rotor can be appropriately monitored based on the voltage command value.

  Next, a first aspect of the synchronous motor control system of the present invention is the rotor rotation monitoring device of the first invention, the magnetic pole position grasping means for detecting or estimating the magnetic pole position of the rotor, and the magnetic pole position grasping means. Magnetic pole position abnormality detecting means for detecting the presence or absence of abnormality of the detected or estimated magnetic pole position in the operation of the synchronous motor in a state where the occurrence of the abnormality is not detected by the magnetic pole position abnormality detection means, A control system for a synchronous motor configured to determine the voltage command value by causing the voltage command value determination unit to execute a calculation process of vector control using the magnetic pole position detected or estimated by the magnetic pole position grasping unit. The monitoring means is in a situation where the rotational motion state of the rotor should be monitored when the occurrence of the abnormality is detected by the magnetic pole position abnormality detection means. As a means for holding the current command value input to the voltage command value determining means at "0" and determining whether or not the rotation of the rotor is stopped based on the monitoring voltage command value, After the occurrence of the abnormality is detected by the magnetic pole position abnormality detection means, the supply of power to the voltage application means is cut off when the monitoring means determines that the rotation of the rotor is stopped. An error processing execution means for executing predetermined error processing including processing is provided (third invention).

  According to the third aspect of the present invention, the current command input to the voltage command value determination unit when the occurrence of the abnormality of the magnetic pole position detected or estimated by the magnetic pole position detection unit is detected by the magnetic pole position abnormality detection unit. The value is held at “0” and it is determined whether the rotation of the rotor is stopped based on the monitoring voltage command value. When the rotation of the rotor is stopped, that is, when the rotation speed of the rotor is “0”, the magnitude of the applied voltage of the armature winding defined by the monitoring voltage command value is “ 0 ”. Therefore, it is possible to determine whether the rotation of the rotor is stopped based on the monitoring voltage command value.

  In the third invention, the error processing execution means detects the occurrence of an abnormality in the magnetic pole position detected or estimated by the magnetic pole position grasping means by the magnetic pole position abnormality detection means, and then the monitoring means performs the rotor operation. When it is determined that the rotation of the power supply is stopped, an error process including a process of cutting off the supply of power to the voltage applying unit is executed. For this reason, the supply of the power supply to the voltage applying means is cut off after it is confirmed that the rotation of the rotor of the motor has stopped. As a result, it is possible to reliably prevent the elements provided in the drive circuit from being damaged by the induced voltage generated in the armature winding of the electric motor.

  Therefore, according to the third invention, it is possible to appropriately perform processing when an abnormality in the magnetic pole position detected or estimated by the magnetic pole position grasping means has occurred using the rotor rotation monitoring device of the first invention.

  In the third invention, as in the second invention, a speed estimation means for estimating the electrical angular speed of the rotor from the monitoring voltage command value, and an integral value of the electrical angular speed estimated by the speed estimation means is obtained from the rotor. The voltage command value determining means, wherein the voltage command value determining means is the magnetic pole position determined by the integrating means while the current command value is held at "0" by the monitoring means. The voltage command value is determined by executing a vector control calculation process using the estimated value. In this case, the integrating means uses the magnetic pole position detected or estimated by the magnetic pole position grasping means as the initial value of the integrated value immediately before the occurrence of the abnormality is detected by the magnetic pole position abnormality detecting means. It is preferable that the magnetic pole position estimation value is obtained (fourth invention).

  According to the fourth aspect of the invention, the integrating means is detected by the magnetic pole position grasping means immediately before the occurrence of the abnormality of the magnetic pole position detected or estimated by the magnetic pole position grasping means is detected by the magnetic pole position abnormality detecting means. Alternatively, since the estimated magnetic pole position is obtained using the estimated magnetic pole position as an initial value of the integral value, the error of the estimated magnetic pole position with respect to the actual magnetic pole position can be reduced. For this reason, the voltage command value determination means can determine the voltage command value so that the current of the armature winding of the motor converges to “0” more quickly. As a result, a state where the rotational motion state of the rotor can be appropriately monitored based on the voltage command value can be realized even more quickly.

  According to a second aspect of the synchronous motor control system of the present invention, the rotor rotation monitoring device according to the first or second aspect of the present invention is provided, and the magnetic pole position of the rotor is estimated during operation of the synchronous motor. In the synchronous motor control system configured to determine the voltage command value by causing the voltage command value determining unit to execute a calculation process of sensorless control, the monitoring unit generates a request to start operation of the synchronous motor. In this case, assuming that the rotational motion state of the rotor is to be monitored, the current command value to be input to the voltage command value determining means is held at “0” and based on the monitoring voltage command value, It is means for determining whether or not the rotation of the rotor is stopped. When the monitoring means determines that the rotation of the rotor is stopped, the synchronous motor Characterized by starting the rotation (fifth invention).

  According to the fifth aspect of the invention, when a request for starting the operation of the synchronous motor is generated, that is, in a situation where the operation of the synchronous motor is to be started, the current command value input to the voltage command value determining means is “ Whether the rotation of the rotor is stopped or not is determined based on the monitoring voltage command value. When the rotation of the rotor is stopped, the magnitude of the applied voltage of the armature winding defined by the monitoring voltage command value is “0”, so that it is the same as in the case of the third invention. In addition, it is possible to determine whether the rotation of the rotor is stopped based on the monitoring voltage command value.

  In the fifth aspect of the invention, the operation of the synchronous motor is started when the monitoring means determines that the rotation of the rotor is stopped. That is, after it is confirmed that the rotation of the rotor of the electric motor has stopped, an operation for determining the voltage command value is started by a calculation process of sensorless control including an estimation process of the magnetic pole position of the rotor. As a result, even if the rotor of the electric motor is rotating before the start of operation of the synchronous motor due to the load state of the electric motor or the like, after the rotation of the rotor of the electric motor is surely stopped, Operation can be started. In other words, the operation of the electric motor can be started from a state in which the magnetic pole position can be appropriately estimated by sensorless control.

  Therefore, according to the fifth aspect of the present invention, it is possible to appropriately start the operation of the electric motor in the sensorless control system.

  In the calculation process of the vector control, the estimated direction of the magnetic field direction (so-called d-axis direction) of the field pole of the rotor is the γ-axis direction, and the direction orthogonal to the γ-axis direction (so-called q-axis direction estimated direction) is δ. The command value (target value) of the voltage in each axial direction in the γδ coordinate system as the axial direction may be determined as the voltage command value. In this case, the magnitude of the combined vector of the γ-axis voltage command value (voltage command value in the γ-axis direction) and the δ-axis voltage command value (voltage command value in the δ-axis direction) is the magnitude of the applied voltage of the armature winding. It will be shown.

  A first embodiment of the present invention will be described below with reference to FIGS. In addition, this embodiment is one Embodiment of the said 1st-4th invention.

  FIG. 1 is a block diagram showing the overall configuration of a synchronous motor control system in the present embodiment. In the figure, reference numeral 1 is a synchronous motor, and 2 is a control device that controls the operation of the synchronous motor 1.

  The synchronous motor 1 is a motor called PMSM (Permanent Magnet Synchronous Motor), that is, a synchronous motor having a permanent magnet in its rotor. In this case, the synchronous motor 1 may be either an IPMSM (Interior Permanent Magnet Synchronous Motor) of the PMSM or an SPMSM (Surface Permanent Magnet Synchronous Motor). Further, in the present embodiment, the synchronous motor 1 (hereinafter sometimes simply referred to as the “motor 1”) is a multi-phase armature winding (stator coil), for example, an electric machine for three phases of U phase, V phase, and W phase. Has a child winding. Connected to the output shaft 1 a of the electric motor 1 is a load W that applies the output torque of the electric motor 1.

  The armature winding of the electric motor 1 is connected to a DC power source (not shown) via a power drive unit 3 (hereinafter referred to as PDU 3) as a drive circuit unit, and energized between the DC power source via the PDU 3 Is done. The PDU 3 includes an inverter circuit (not shown), and phase voltage command values vu_c, vv_c, and vw_c, which are target values of applied voltages of the U-phase, V-phase, and W-phase armature windings of the electric motor 1, respectively. It is input from the control device 2. The PDU 3 switches the inverter circuit by PWM control so that the actual applied voltage (output voltage of the inverter circuit) of the armature winding of each phase becomes the input phase voltage command values vu_c, vv_c, vw_c. Controls on / off of the element. Thereby, the voltages of the phase voltage command values vu_c, vv_c, and vw_c are applied from the PDU 3 to the armature windings of the respective phases of the electric motor 1. As a result, the current (phase current) of the armature winding of each phase is controlled in accordance with the phase voltage command values vu_c, vv_c, and vw_c.

  In the control system of the present embodiment, the following sensors are provided to control the operation of the electric motor 1. In other words, the current path between the PDU 3 and the motor 1 is a current sensor that detects currents (phase currents) flowing through at least two of the three phases, for example, U-phase and V-phase armature windings. 4 and 5 are provided. Further, the electric motor 1 is provided with a magnetic pole position sensor 6 for detecting a rotational angle position (hereinafter simply referred to as a magnetic pole position) of a permanent magnet of the rotor with respect to the stator from a predetermined reference position. The magnetic pole position sensor 6 is composed of, for example, a resolver, a Hall element, a rotary encoder, and the like, and generates an output corresponding to the magnetic pole position of the rotor.

  The control device 2 is an electronic circuit unit configured by a microcomputer or the like. The control device 2 performs control related to the operation of the electric motor 1 by executing a control process realized by a program installed in advance. In this case, the main control process executed by the control device 2 is a control process for normal operation (hereinafter referred to as normal mode) executed when the electric motor 1 is operated when the magnetic pole position detected by the magnetic pole position sensor 6 is normal. Control processing) and control processing (hereinafter referred to as fail mode control processing) executed when an abnormality occurs in the magnetic pole position detected by the magnetic pole position sensor 6 due to failure of the magnetic pole position sensor 6 or the like. .

  In the normal mode control process, the control device 2 sequentially determines the phase voltage command values vu_c, vv_c, and vw_c so that the actual rotational speed of the rotor of the electric motor 1 coincides with the target rotational speed. Output. Thereby, the control device 2 controls the energization of the armature windings of the respective phases of the electric motor 1 via the PDU 3 so that the actual rotational speed of the rotor of the electric motor 1 matches the target rotational speed.

  In the fail mode control process, the control device 2 sets the phase voltage command values vu_c, vv_c, vw_c so as to keep the current (phase current) of the armature winding of each phase of the motor 1 at “0”. It determines sequentially and outputs to PDU3. As a result, the control device 2 prevents current from flowing through the armature winding of each phase of the electric motor 1. Further, the control device 2 estimates the electrical angular velocity of the rotor of the motor 1 by a predetermined calculation process while maintaining the current (phase current) of the armature windings of each phase at “0” in this way. The electrical angular velocity is monitored as an index indicating the rotational motion state of the rotor. When it is confirmed that the electrical angular velocity becomes “0” and the rotation of the rotor of the electric motor 1 is stopped, the control device 2 performs a predetermined error including a process of cutting off the power supply to the PDU 3. Execute the process.

  The control device 2 that executes these control processes receives the U-phase current detection value iu_s and the V-phase current detection value iv_s respectively indicated by the outputs of the current sensors 4 and 5, and the magnetic pole position sensor 6 The magnetic pole position detection value θe indicated by the output of. Furthermore, a speed command value ωr_c that is a target value of the rotational speed of the rotor of the electric motor 1 in the normal mode control process is input to the control device 2 from the outside. The magnetic pole position detection value θe and the speed command value ωr_c are used in the normal mode control process and are not used in the fail mode control process. Supplementally, in this embodiment, the magnetic pole position detection value θe is the magnetic pole position at the electrical angle, and the speed command value ωr_c is the target value of the rotational speed (angular speed) at the mechanical angle.

  In this case, in this embodiment, in both the normal mode control process and the fail mode control process, the control device 2 basically sets the magnetic flux direction of the permanent magnet of the rotor of the electric motor 1 in the d-axis direction, and this d-axis. The phase voltage command values vu_c, vv_c, and vw_c are sequentially determined by vector control arithmetic processing that handles the motor 1 in a so-called dq coordinate system in which the direction orthogonal to the direction is the q-axis direction. The dq coordinate system is a rotating coordinate system that rotates integrally with the rotor with respect to the stator of the electric motor 1.

  Here, in general, when such vector control calculation processing is executed, the d-axis direction of the dq coordinate system is based on the detected value of the magnetic pole position of the rotor by the sensor or the estimated value of the magnetic pole position by an appropriate estimation calculation. And q-axis direction is recognized (estimated). Then, vector control calculation processing is executed in the recognized dq coordinate system. In this case, when the detected value or estimated value of the magnetic pole position of the rotor has an error with respect to the true value, the d-axis direction and the q-axis direction recognized from the detected value or estimated value are the actual ( Deviation occurs with respect to the true d-axis direction and the q-axis direction. In this case, the d-axis direction and the q-axis direction recognized (estimated) from the detected value or estimated value of the magnetic pole position of the rotor are referred to as the γ-axis direction and the δ-axis direction, respectively. A rotating coordinate system in which the γ-axis direction and the δ-axis direction are biaxial directions is called a γδ coordinate system.

  FIG. 2 shows the relationship between the dq coordinate system and the γδ coordinate system. If the error (deviation) of the detected value or estimated value of the rotor magnetic pole position with respect to the true value is Δθe, the γ-axis direction and δ-axis direction of the γδ coordinate system are the d-axis direction and the q-axis, respectively, as shown in the figure. The phase (angle) is shifted from the direction by Δθe. When Δθe = 0, the γ-axis direction and the δ-axis direction coincide with the d-axis direction and the q-axis direction, respectively.

  The vector control calculation process executed by the control device 2 in this embodiment is a process in the γδ coordinate system as an estimated coordinate system of the dq coordinate system. In this case, the γ-axis direction and δ-axis direction of the γδ coordinate system in the normal mode control processing are directions recognized based on the magnetic pole position detection value θe by the magnetic pole position sensor 6. In the fail mode control process, the direction is recognized based on a simple magnetic pole position estimated value θe_e described later.

  Based on the outline of the control process of the control device 2 described above, the details of the control process will be described below. As shown in FIG. 1, the control device 2 is calculated by differentiating the magnetic pole position detection value θe by the magnetic pole position sensor 6 (determining the amount of change per unit time of θe) as a functional means of the control processing. The speed calculation unit 10 for determining the rotational speed ωr of the rotor at the mechanical angle (hereinafter referred to as the speed detection value ωr) by dividing the electrical angular speed by the rotor pole pair, and the speed command value ωr_c input from the outside, A deviation calculator 11 for obtaining a deviation Δω (= ωr_c−ωr; hereinafter referred to as a speed deviation Δωr) with respect to the speed detection value ωr, and in order to converge the speed deviation Δωr to “0” according to the speed deviation Δωr. Of the target value iγ_c1 of the γ-axis current (current component of the armature winding current in the γ-axis direction) and the target value iδ_c1 of the δ-axis current (current component of the armature winding current in the δ-axis direction) Determined by known arithmetic processing such as feedback rules And a speed controller 12 for.

  Here, in the present embodiment, the target values of the γ-axis current and the δ-axis current of the electric motor 1 include a target value in the normal mode control process and a target value in the fail mode control process. The target values iγ_c1 and iδ_c1 of the γ-axis current and δ-axis current determined by the speed control unit 12 are target values in the normal mode control process. The target values of the γ-axis current and the δ-axis current in the fail mode control process are both “0”. In the following description, the target values iγ_c1 and iδ_c1 of the γ-axis current and δ-axis current in the normal mode control process are referred to as a first γ-axis current command value iγ_c1 and a first δ-axis current command value iδ_c1, respectively. The target values of the γ-axis current and the δ-axis current in the fail mode control process are referred to as a second γ-axis current command value (= 0) and a second δ-axis current command value (= 0), respectively.

  Then, the control device 2 sets the target value iγ_c (hereinafter referred to as the actual use γ-axis current command value iγ_c) of the actually used γ-axis current, the first γ-axis current command value iγ_c1 and the second γ-axis current command value (= 0). ) And the target value iδ_c of the actually used δ-axis current (hereinafter referred to as the actual used δ-axis current command value iδ_c) is set as the first δ-axis current command value. a δ-axis current command selection switching unit that selectively determines from iδ_c1 and a δ-axis current command value for fail mode. The γ-axis current command selection switching unit 13 selects the first γ-axis current command value iγ_c1 as the actual use γ-axis current command value iγ_c when the normal mode control process is executed, and the actual use γ when the fail mode control process is executed. The second γ-axis current command value (= 0) is selected as the shaft current command value iγ_c. Similarly, the δ-axis current command selection switching unit 14 selects the first δ-axis current command value iδ_c1 as the actual use δ-axis current command value iδ_c when executing the normal mode control process, and when executing the fail mode control process, The second δ-axis current command value (= 0) is selected as the actual use δ-axis current command value iδ_c.

  In the following description, for convenience of explanation, the γ-axis current command selection switching unit 13 and the δ-axis current command selection switching unit 14 may be referred to as switches 13 and 14 in terms of their functions. In this case, when the γ-axis current command selection switching unit 13 selects the first γ-axis current command value iγ_c1 as iγ_c, the operation position of the switch 13 is the normal mode position, and the second γ-axis current command value (= 0) as iγ_c. The operation position of the switch 13 when selecting is referred to as a fail mode position. Similarly, when the δ-axis current command selection switching unit 14 selects the first δ-axis current command value iδ_c1 as iδ_c, the operation position of the switch 14 is the normal mode position, and the second δ-axis current command value (= 0) as iδ_c. The operation position of the switch 14 when selecting is referred to as a fail mode position.

  Further, the control device 2 receives the U-phase current detection value iu_s and the V-phase current detection value iv_s by the current sensors 4 and 5, and the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c. And a voltage command value determination unit 15 for obtaining a set of the phase voltage command values vu_c, vv_c, and vw_c based on these input values.

  More specifically, the voltage command value determination unit 15 is configured to detect a γ-axis current detection value iγ and a δ-axis current using a set of the input U-phase current detection value iu_s and V-phase current detection value iv_s as a γ-axis current detection value. Uvw / γδ coordinate conversion unit 15a that converts the detected value into a set of δ-axis current detection value iδ, and deviation Δiγ between the actually used γ-axis current command value iγ_c and the γ-axis current detection value iγ (= a deviation calculating unit 15b for calculating (iγ_c−iγ), a deviation calculating unit 15c for calculating a deviation Δiδ (= iδ_c−iδ) between the actually used δ-axis current command value iδ_c and the detected δ-axis current value iδ, From the deviations Δiγ and Δiδ, a γ-axis voltage command value as a target value of a γ-axis voltage (component of the armature winding voltage in the γ-axis direction) for converging these deviations Δiγ and Δiδ to “0”, respectively. As target values of vγ_c and δ-axis voltage (component of armature winding voltage in δ-axis direction) A γ-axis current control unit 15d and a δ-axis current control unit 15e that respectively determine the δ-axis voltage command value vδ_c by a known calculation process such as a feedback rule, and the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c The set is composed of a γδ / uvw coordinate conversion unit 15f that converts the set into a set of the phase voltage command values vu_c, vv_c, and vw_c. Therefore, the voltage command value determining unit 15 converges the γ-axis current detection value iγ and the δ-axis current detection value iδ to the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c (see above). A set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c, and thus a set of the phase voltage command values vu_c, vv_c, and vw_c, is determined so that the deviations Δiγ and Δiδ converge to “0”.

  Here, the uvw / γδ coordinate conversion unit 15a uses a known coordinate system in which a vector composed of a set of the U-phase current detection value iu_s and the V-phase current detection value iv_s is defined according to the magnetic pole position of the rotor of the electric motor 1. By performing coordinate transformation using the transformation matrix, a set of the γ-axis current detection value iγ and the δ-axis current detection value iδ is calculated. In addition, the γδ / uvw coordinate conversion unit 15f is a known coordinate conversion matrix in which a vector composed of a set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c is defined according to the magnetic pole position of the rotor of the electric motor 1. The set of the phase voltage command values vu_c, vv_c, and vw_c is calculated by performing coordinate conversion according to.

  In this case, in this embodiment, the value of the magnetic pole position used in the coordinate conversion of the uvw / γδ coordinate conversion unit 15a and the γδ / uvw coordinate conversion unit 15f (hereinafter referred to as coordinate conversion magnetic pole position θa) is a magnetic pole position sensor. 6, and a magnetic pole position detection value θe_e calculated by an integrator 23 described later. Then, the control device 2 of the present embodiment selectively determines the coordinate conversion magnetic pole position θa from the magnetic pole position detection value θe and the magnetic pole position simple estimation value θe_e, and the uvw / γδ coordinate conversion unit 15a and γδ / A coordinate conversion magnetic pole position selection switching unit 21 to be provided to the uvw coordinate conversion unit 15f is provided. The coordinate conversion magnetic pole position selection switching unit 21 selects the magnetic pole position detection value θe as the coordinate conversion magnetic pole position θa when the normal mode control process is executed, and when the fail mode control process is executed, the magnetic pole position simple estimated value is selected. Select θe_e.

  In the following description, for convenience of description, the coordinate conversion magnetic pole position selection switching unit 21 may be referred to as a switch 21 in terms of its function. In this case, the coordinate conversion magnetic pole position selection switching unit 21 selects the operation position of the switch 21 when the magnetic pole position detection value θe is selected as θa, and selects the magnetic pole position simple estimated value θe_e as θa. The operating position of the switch 21 is referred to as a fail mode position.

  Further, the control device 2 includes a magnetic pole position abnormality detection unit 22 (magnetic pole position abnormality detection means) that detects whether or not an abnormality of the magnetic pole position detection value θe input from the magnetic pole position sensor 6 has occurred, and the fail mode control process. At the time of execution, a simple speed estimation unit 23 that estimates the electrical angular speed of the rotor of the electric motor 1 by simple arithmetic processing, and the electrical angular speed estimated by the simple speed estimation unit 23 (hereinafter referred to as a simple electrical angular speed estimated value ωe_e) Is integrated to calculate the magnetic pole position simple estimated value θe_e as a simple estimated value of the rotor magnetic pole position, and whether the electric angular velocity simple estimated value ωe_e is “0” or not. A rotation speed determination unit 25 for determining, and an error processing unit 26 for executing error processing according to the determination result of the rotation speed determination unit 25 are provided.

  In this case, the magnetic pole position detection value θe is sequentially input to the magnetic pole position abnormality detection unit 22 in order to detect the occurrence of the abnormality of the magnetic pole position detection value θe by the magnetic pole position sensor 6. Then, the magnetic pole position abnormality detection unit 22 detects that an abnormality of the magnetic pole position detection value θe has occurred, for example, when the temporal change rate of the input magnetic pole position detection value θe exceeds a predetermined threshold.

  Supplementally, depending on the type of the magnetic pole position sensor 6, when an abnormality occurs in the magnetic pole position sensor 6, an abnormality occurrence signal indicating this may be output from the magnetic pole position sensor 6. In such a case, the magnetic pole position abnormality detection unit 22 may determine whether or not an abnormality has occurred in the magnetic pole position detection value θe based on the presence or absence of the output of the abnormality occurrence signal.

  The simple speed estimation unit 23 receives a γ-axis voltage command value vγ_c and a δ-axis voltage command value vδ_c determined by the γ-axis current control unit 18 and the δ-axis current control unit 19, respectively. Then, the simple speed estimation unit 22 calculates the electrical angular speed simple estimation value ωe_e from these input values. Details of this calculation processing will be described below.

  The voltage equation of the electric motor 1 in the dq coordinate system is generally expressed by the following equation (1).

なお、ｖd：ｄ軸電圧、ｖq：ｑ軸電圧、ｉd：ｄ軸電流、ｉq：ｑ軸電流、Ｌd：ｄ軸インダクタンス、Ｌq：ｑ軸インダクタンス、Ｒ：抵抗、ωe：電気角速度、Ｋe：誘起電圧定数、ｐ：微分演算子である。

Vd: d-axis voltage, vq: q-axis voltage, id: d-axis current, iq: q-axis current, Ld: d-axis inductance, Lq: q-axis inductance, R: resistance, ωe: electrical angular velocity, Ke: induction Voltage constant, p: differential operator.

  If the γ-axis direction and the δ-axis direction of the γδ coordinate system have a phase difference of an angle Δθe as shown in FIG. 2 with respect to the d-axis direction and the q-axis direction of the dq coordinate system, The voltage equation is expressed by the following equation (2).

なお、ｖγ：γ軸電圧、ｖδ：δ軸電圧、ｉγ：γ軸電流、ｉδ：δ軸電流である。

Note that vγ: γ-axis voltage, vδ: δ-axis voltage, iγ: γ-axis current, iδ: δ-axis current.

  Here, in the equation (2), when iγ = iδ = 0, the following equation (3) is obtained.

従って、電動機１の電機子巻線の電圧のγδ座標系での大きさ、すなわち、γ軸電圧ｖγとδ軸電圧ｖδの合成電圧ベクトルの大きさ｜ｖ_γδ｜と、ロータの電気角速度ωe_eとの間には、Δθeに依存することなく、次式（４ａ）または（４ｂ）の関係（比例関係）が成立する。

Therefore, the magnitude of the voltage of the armature winding of the motor 1 in the γδ coordinate system, that is, the magnitude | v _γδ | of the combined voltage vector of the γ-axis voltage vγ and the δ-axis voltage vδ, and the electrical angular velocity ωe_e of the rotor The relationship (proportional relationship) of the following equation (4a) or (4b) is established without depending on Δθe.

従って、電動機１のロータが回転している状態で、電動機１の各相の電機子巻線の実際の電流が“０”になるように（ひいては、γ軸電流およびδ軸電流が“０”なるように）、各相の電機子巻線への印加電圧を制御した状態では、式（４ａ）または式（４ｂ）により、ロータの電気角速度ωe_eを推定することができることとなる。

Therefore, in a state where the rotor of the electric motor 1 is rotating, the actual currents of the armature windings of the respective phases of the electric motor 1 become “0” (as a result, the γ-axis current and the δ-axis current are “0”. Thus, in a state where the voltage applied to the armature winding of each phase is controlled, the electrical angular velocity ωe_e of the rotor can be estimated from the equation (4a) or the equation (4b).

  Therefore, in the present embodiment, in the fail mode control process, the control device 2 operates the switches 13 and 14 to the fail mode position so that the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value. Both iδ_c are held at “0”. That is, in the control device 2, both the γ-axis current and the δ-axis current are held at “0”, and the actual current of the armature winding of each phase of the motor 1 is held at “0”. The voltage applied to the armature winding of each phase of the electric motor 1 is controlled with the goal of. In this state, the simple speed estimator 23 calculates from the input γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c according to the sign of vδ_c according to the equation (4a) or (4b). The electrical angular velocity simple estimated value ωe_e is calculated.

More specifically, the simple speed estimation unit 23 calculates the magnitude | v _γδ | of these combined voltage vectors from the input γ-axis voltage command value vγ_c and δ-axis voltage command value vδ_c according to the equation (4c). calculate. Then, when vδ_c> 0, the simple speed estimation unit 22 uses the calculated | v _γδ | to perform the calculation on the right side of the equation (4a), thereby obtaining the electrical angular speed simple estimation value ωe_e. calculate. Further, when vδ_c <0, the simple speed estimation unit 22 uses the calculated | v _γδ | to perform the calculation on the right side of the equation (4b), thereby obtaining the electrical angular speed simple estimation value ωe_e. calculate. In this case, the value of the induced voltage constant Ke necessary for the calculations of the equations (4a) and (4b) is a proportional constant representing the relationship (proportional relationship) between the electrical angular velocity ωe of the rotor of the motor 1 and the induced voltage. Values identified based on experiments or the like are used.

  The details of the calculation processing of the simple speed estimation unit 22 have been described above.

  Supplementally, in this embodiment, the PDU 3 corresponds to the voltage applying means in the present invention, the current sensors 4 and 5 correspond to the current detecting means in the present invention, and the magnetic pole position sensor 6 serves as the magnetic pole position grasping means in the present invention. Equivalent to. The voltage command value determination unit 15 corresponds to voltage command value determination means in the present invention, the integrator 24 corresponds to integration means in the present invention, and the simple speed estimation unit 23 corresponds to speed estimation means in the present invention. To do. The monitoring means in the present invention is realized by the γ-axis current command selection switching unit 13 (switch 13), the δ-axis current command selection switching unit 14 (switch 14), the simple speed estimation unit 23, and the rotation speed determination unit 25. The In this case, the γ-axis voltage command value vγ_c determined by the voltage command value determination unit 15 in a state where both the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c are held at “0”. A set with the δ-axis voltage command value vδ_c corresponds to the monitoring voltage command value in the present invention. Further, the magnetic pole position abnormality detection unit 22 corresponds to a magnetic pole position abnormality detection unit in the present invention, and the error processing unit 26 corresponds to an error processing execution unit in the present invention.

  Next, the overall control processing of the control device 2 will be described with reference to FIG. FIG. 3 is a flowchart showing the overall control process.

  When the electric motor 1 is in operation when the magnetic pole position detection value θe by the magnetic pole position sensor 6 is normal, the control device 2 performs normal mode control processing (STEP 1), and the magnetic pole position abnormality detection unit 22 detects the magnetic pole position detection value. The presence or absence of an abnormality in θe is monitored (STEP 2).

  In this case, in the normal mode control process, the operating positions of the switches 13, 14, and 21 are all normal mode positions. In this state, the above-described processes of the speed calculation unit 10, the deviation calculation unit 11, the speed control unit 12, and the voltage command value determination unit 15 are sequentially executed at a predetermined calculation processing cycle. Thereby, a set of the phase voltage command values vu_c, vv_c, and vw_c is sequentially determined. The voltages of the phase voltage command values vu_c, vv_c, and vw_c are applied from the PDU 3 to the armature windings of the respective phases of the electric motor 1 as described above, and the energization of the respective armature windings of the electric motor 1 is controlled. The

  In this normal mode control process, since the operating position of the switches 13 and 14 is the normal mode position, the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c input to the voltage command value determination unit 15. Are the first γ-axis current command value iγ_c1 and the first δ-axis current command value iδ_c1 determined by the speed control unit 12, respectively. For this reason, a set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c determined by the γ-axis current control unit 15d and the δ-axis current control unit 15e of the voltage command value determination unit 15, respectively, and thus the phase voltage command A set of values vu_c, vv_c, and vw_c is determined so that the detected γ-axis current value iγ_c and the detected δ-axis current value iδ_c converge to the first γ-axis current command value iγ_c1 and the first δ-axis current command value iδ_c1, respectively. The Accordingly, the energization of the armature windings of each phase of the electric motor 1 is feedback-controlled so that the speed detection value ωr becomes the speed command value ωr_c.

  In the normal mode control process, in the coordinate conversion process of the uvw / γδ coordinate conversion unit 15 and the γδ / uvw coordinate conversion part 20, the magnetic pole position detection value θe by the magnetic pole position sensor 6 is used as the coordinate conversion magnetic pole position θa. The

  As described above, when the control device 2 executes the normal mode control process, if an abnormality of the magnetic pole position detection value θe occurs due to a failure of the magnetic pole position sensor 6 or the like, this is detected by the magnetic pole position abnormality detection unit 22. Detected (YES in STEP 2) At this time, in STEP 3, the operating positions of the switches 13, 14, and 21 are switched from the normal mode position to the fail mode position, respectively, and the fail mode control process is started.

  In this case, in the fail mode control process, the above-described process of the voltage command value determining unit 15 is sequentially executed at a predetermined calculation process cycle in a state where the switches 13, 14, and 21 are respectively moved to the fail mode position. . Thereby, a set of the phase voltage command values vu_c, vv_c, and vw_c is sequentially determined. Then, the voltages of the phase voltage command values vu_c, vv_c, vw_c are applied from the PDU 3 to the armature windings of the respective phases of the electric motor 1. Further, in the fail mode control process, in parallel with the determination of the phase voltage command values vu_c, vv_c, vw_c as described above, the simple speed estimation unit 23, the integrator 24, the rotation speed determination unit 25, and the error processing unit. 26 processes are executed.

  In this fail mode control process, since the operating positions of the switches 13 and 14 are in the fail mode position, the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c are respectively the second γ-axis current command. Value (= 0), the second δ-axis current command value (= 0). That is, iγ_c and iδ_c are constantly held at “0”. For this reason, in the voltage command value determining unit 15, the set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c, and hence the set of the phase voltage command values vu_c, vv_c, vw_c, The current flowing in the child winding is determined so as to be constantly maintained at “0”. In other words, the voltage applied from the PDU 3 to the armature winding of each phase of the motor 1 defined by the phase voltage command values vu_c, vv_c, vw_c is generated in the armature winding of each phase as the rotor rotates. The phase voltage command values vu_c, vv_c, and vw_c are determined so as to cancel the induced voltage. As a result, the voltage applied from the PDU 3 to the armature winding of each phase is controlled so that the current of the armature winding of each phase of the electric motor 1 becomes “0”.

  The simple speed estimation unit 23 controls the γ-axis voltage command value vγ_c and the δ-axis voltage command value while controlling the armature winding current of each phase of the motor 1 to be “0”. From vδ_c, the electrical angular velocity simple estimated value ωe_e is sequentially calculated at a predetermined calculation processing cycle according to the equation (4a) or (4b). Further, the integrator 24 sequentially integrates the electrical angular velocity simple estimated value ωe_e, and sequentially calculates the magnetic pole position simplified estimated value θe_e. The simple magnetic pole position estimated value θe_e calculated by the integrator 24 in this way is sent to the uvw / γδ coordinate conversion unit 15a and γδ / uvw coordinate conversion unit 15f via the coordinate conversion magnetic pole position selection switching unit 21 (switch 21). Is given as the coordinate conversion magnetic pole position θa. In the present embodiment, in the integration process of the integrator 24, the magnetic pole position detection immediately before the occurrence of the abnormality of the magnetic pole position detection value θe is detected by the magnetic pole position abnormality detection unit 22 (immediately before the start of the fail mode control process). The value θe is set as the initial value of the magnetic pole position simple estimated value θe_e.

  Returning to the explanation of FIG. 3, during the execution of the fail mode control process as described above, the electrical angular speed simple estimated value ωe_e calculated by the simple speed estimating unit 23 is monitored by the rotational speed determining unit 24, and the electrical angular speed simple It is determined whether or not the estimated value ωe_e has become “0” (STEP 4). Here, immediately after the occurrence of the abnormality of the magnetic pole position detection value θe, the rotor of the electric motor 1 is generally rotated by the operation control of the electric motor 1 before the occurrence. Thus, when the rotor is rotating, since ωe_e ≠ 0, the determination result in STEP 4 is negative. In this state, the determination process in STEP 4 is continuously performed.

  Thereafter, when the rotation of the rotor of the electric motor 1 is stopped, the determination result in STEP 4 becomes affirmative. At this time, the error processing unit 25 executes predetermined error processing (STEP 5). In this error processing, for example, the error processing unit 25 turns off a switch (not shown) provided between the DC power supply and the PDU 3 to cut off the supply of power from the DC power supply to the PDU 3. Further, the error processing unit 25 executes a reset process of the control system of the electric motor 1 and the like.

  The above is the overall control processing of the control device 2.

  In this embodiment, when the occurrence of an abnormality in the magnetic pole position detection value θe is detected by the magnetic pole position abnormality detection unit 22 during the operation of the electric motor 1, the control device 2 first performs the fail mode control process. The γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c that define the voltage applied from the PDU 3 to the armature winding so that the current of the armature winding of each phase of the electric motor 1 is maintained at “0”. And, in turn, phase voltage command values vu_c, vv_c, and vw_c are determined. Then, while determining vγ_c and vδ_c in this way, the control device 2 executes the arithmetic processing of the simple speed estimation unit 23 and the integrator 24.

  At this time, calculation processing of the simple speed estimation unit 23 is performed while controlling the applied voltage of the armature winding of the electric motor 1 so that the current of the armature winding of each phase of the electric motor 1 is kept at “0”. Therefore, it is possible to calculate the electrical angular velocity simple estimated value ωe_e having sufficient reliability as an estimated value of the actual electrical angular velocity of the rotor of the electric motor 1. Therefore, the rotational motion state of the rotor after the occurrence of the abnormality of the magnetic pole position detection value θe can be grasped by the simple electrical angular velocity estimated value ωe_e.

  In this case, the magnetic pole position simple estimated value θe_e calculated by the integrator 24 in the fail mode control process, that is, the uvw / γδ coordinate conversion unit 15a and the γδ / uvw coordinate conversion unit 15f are supplied with the coordinate conversion magnetic pole position θa. The magnetic pole position simple estimated value θe_e given as follows changes in synchronization with the rotation period of the rotor. For this reason, the phase voltage command values vu_c, vv_c, vw_c calculated by the γδ / uvw coordinate conversion unit 15f, and thus the voltage applied from the PDU 3 to the armature windings of each phase of the motor 1 are relatively quickly obtained. It becomes synchronized with the induced voltage generated in the armature winding. As a result, after detecting the occurrence of an abnormality in the magnetic pole position detection value θe, the current of the armature winding of each phase of the electric motor 1 can be quickly converged to “0” while suppressing frequent fluctuations. . In particular, in the present embodiment, as described above, the magnetic pole position detection value θe immediately before the occurrence of the abnormality of the magnetic pole position detection value θe is detected (immediately before the start of the fail mode control process) is the initial value of the magnetic pole position simple estimation value θe_e. Therefore, the error of the magnetic pole position simple estimated value θe_e calculated by the integrator 24 immediately after the start of the fail mode control process is relatively small. For this reason, the current of the armature winding of each phase of the electric motor 1 can be smoothly and quickly converged to “0”.

  Since the current of the armature winding of each phase of the electric motor 1 can be quickly converged to “0” in this way, the electric angular velocity simple estimated value ωe_e having high reliability is obtained as the simple velocity estimating unit 23. The state that can be calculated by this can be quickly realized after the occurrence of the abnormality in the magnetic pole position detection value θe. That is, the electrical angular velocity of the rotor of the electric motor 1 can be estimated with high reliability immediately after the occurrence of the abnormality in the magnetic pole position detection value θe.

  Further, when the electrical angular speed simple estimated value ωe_e calculated by the simple speed estimating unit 23 becomes “0”, that is, the rotation of the rotor of the electric motor 1 is stopped and the control device 2 stops the electric motor 1. When the generated induced voltage becomes “0” or sufficiently small, the error processing unit 25 executes error processing to cut off the supply of power to the PDU 3. For this reason, it is possible to prevent the drive circuit of the PDU 3 from being damaged by the induced voltage generated in the electric motor 1.

  In the present embodiment, the magnetic pole position detection value θe immediately before the occurrence of the abnormality of the magnetic pole position detection value θe is detected (immediately before the start of the fail mode control process) is set as the initial value of the simple magnetic pole position estimation value θe_e. However, this is not always necessary. For example, the initial value of the magnetic pole position simple estimated value θe_e may be set to a fixed value such as “0” that does not depend on the magnetic pole position detection value θe immediately before the occurrence of the abnormality of the magnetic pole position detection value θe is detected. However, in order to converge the current of the armature winding of each phase of the electric motor 1 to “0” as quickly as possible, it is advantageous to set the initial value of the magnetic pole position simple estimated value θe_e as described above.

  Next, a second embodiment of the present invention will be described with reference to FIGS. This embodiment is an embodiment of the first to fifth inventions. Note that this embodiment is different from the first embodiment only in part of the configuration and control processing. Therefore, the same parts as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment. The description is omitted.

  FIG. 4 is a block diagram showing a functional configuration of the motor control system in the present embodiment. In the figure, 1 is the same synchronous motor (hereinafter simply referred to as an electric motor) as in the first embodiment, and 30 is a control device that controls the operation of the electric motor 1.

  The armature winding of each phase of the electric motor 1 is connected to a DC power source (not shown) via the PDU 3 as in the first embodiment. Further, the current path between the PDU 3 and the armature winding of each phase of the electric motor 1 includes current sensors 4 and 5 as in the first embodiment. However, the magnetic pole position sensor is not provided in the control system of this embodiment. The configuration other than the control device 30 in the system configuration of the present embodiment is the same as that of the first embodiment except that the magnetic pole position sensor is not provided.

  The control device 30 is an electronic circuit unit configured by a microcomputer or the like, similar to the control device 2 of the first embodiment, and executes control processing realized by a program installed in advance, so that the motor 1 Performs control related to operation. In this case, as a main control process executed by the control device 30, a control process for operating the motor 1 while estimating the magnetic pole position of the rotor of the motor 1 by a so-called sensorless control technique (hereinafter referred to as a sensorless control process). And a control process (hereinafter referred to as a pre-startup control process) executed before starting the operation of the electric motor 1 by the sensorless control process, and an abnormal magnetic pole position estimated during the execution of the sensorless control process. There is a control process to be executed (hereinafter referred to as a fail control process).

  In the sensorless control process, the control device 30 estimates the magnetic pole position and the rotational speed of the rotor of the electric motor 1 by a known sensorless control technique, and matches the actual rotational speed of the rotor of the electric motor 1 with the target rotational speed. As described above, the phase voltage command values vu_c, vv_c, and vw_c are sequentially determined and output to the PDU 3. As a result, the control device 30 controls each of the motors 1 via the PDU 3 so that the actual rotational speed of the rotor of the electric motor 1 matches the target rotational speed, as in the normal mode control process in the first embodiment. Controls the current in the armature winding of the phase.

  Further, in the pre-startup control process, the control device 30 keeps the current (phase current) of the armature winding of each phase of the electric motor 1 at “0”, as in the fail mode control process in the first embodiment. The phase voltage command values vu_c, vv_c, and vw_c are sequentially determined and output to the PDU 3. As a result, the control device 30 prevents current from flowing through the armature windings of the respective phases of the electric motor 1. Further, the control device 30 maintains the current (phase current) of the armature winding of each phase at “0” as described above, and similarly to the fail mode control process in the first embodiment, The electrical angular velocity is estimated by a predetermined calculation process, and the estimated electrical angular velocity is monitored as an index indicating the rotational motion state of the rotor. Then, when it is confirmed that the electrical angular velocity becomes zero and the rotation of the rotor of the electric motor 1 is stopped, the control device 30 starts the sensorless control process.

  In the fail control process, the control device 30 executes the same control process as the fail mode control process of the first embodiment. That is, the failure control process will be schematically described. The control device 30 controls the phase voltage command values vu_c, vv_c so as to keep the current (phase current) of the armature winding of each phase of the electric motor 1 at “0”. , Vw_c are sequentially determined, and the electrical angular velocity of the rotor of the electric motor 1 is estimated and monitored. Then, when it is confirmed that the electrical angular velocity becomes “0” and the rotation of the rotor of the electric motor 1 is stopped, the control device 30 performs error processing including processing for cutting off the power supply to the PDU 3. Execute.

  The control device 30 that executes these control processes receives the U-phase current detection value iu_s and the V-phase current detection value iv_s respectively indicated by the outputs of the current sensors 4 and 5. Furthermore, the speed command value ωr_c, which is the target value of the rotational speed of the rotor of the electric motor 1, is inputted to the control device 30 from the outside when the sensorless control process is executed, as in the first embodiment.

  In this case, in this embodiment, in both the sensorless control process and the pre-startup control process, the control device 30 performs the vector voltage command value vu_c by the vector control process in the γδ coordinate system described in the first embodiment. , Vv_c, vw_c are sequentially determined.

  Based on the outline of the control processing of the control device 30 described above, details of the control processing will be described below. In this case, many of the functional means of the control device 30 are the same as those of the control device 2 of the first embodiment. Therefore, in the following description of the control device 30, the parts having the same functions as those of the control device 2 are not described in detail using the same reference numerals as those in the first embodiment, and are different from the control device 2. The explanation will focus on the specific means.

  As shown in FIG. 4, the control device 30 is similar to the control device 2 of the first embodiment in that the deviation calculation unit 11, the speed control unit 12, the γ-axis current command selection switching unit 13 (switch 13), the δ-axis current Command selection switching unit 14 (switch 14), voltage command value determination unit 15, coordinate conversion magnetic pole position selection switching unit 21 (switch 21), magnetic pole position abnormality detection unit 22, simple speed estimation unit 23, integrator 24, rotational speed A determination unit 25 and an error processing unit 26 are provided. And the control apparatus 30 in this embodiment is provided with the magnetic pole position and speed estimation part 31 as a functional means instead of the magnetic pole position sensor 6 and the speed calculation part 10 in 1st Embodiment.

  In this case, the magnetic pole position / velocity estimation unit 31 determines the γ-axis voltage command value determined by the γ-axis current control unit 15d and the δ-axis current control unit 15e of the voltage command value determination unit 15 when the sensorless control process is executed. Based on the vγ_c and δ-axis voltage command value vδ_c and the γ-axis current detection value iγ and the δ-axis current detection value iδ obtained by the uvw / γδ coordinate system conversion unit 15a, a known sensorless control technique is used. An estimated value θe_e1 of the rotor magnetic pole position and an estimated value ωr_e1 of the rotational speed (angular speed at the mechanical angle) are calculated. For example, when the rotational speed of the rotor of the electric motor 1 is low, the magnetic pole position / speed estimation unit 31 calculates the magnetic pole position estimated value θe_e1 by a known method using the inductance of the electric motor 1, and the rotational speed of the rotor is to some extent. When it becomes higher, the magnetic pole position estimated value θe_e1 is calculated by a known method using the induced voltage of the electric motor 1. Further, the estimated rotational speed value ωr_e1 is calculated by dividing the differential value (change amount per unit time) of the magnetic pole position estimated value θe_e1 by the number of pole pairs of the rotor or in the process of calculating the magnetic pole position estimated value θe_e1. Calculated by dividing the electrical angular velocity by the number of pole pairs of the rotor.

  In the present embodiment, the deviation calculator 11 calculates a deviation between the speed command value ωr_c given from the outside to the control device 30 and the estimated rotational speed ωr_e1 calculated by the magnetic pole position / speed estimator 31 as a speed deviation. Calculated as Δωr and input to the speed controller 12.

  In the present embodiment, the magnetic pole position abnormality detection unit 22 is sequentially input with the magnetic pole position estimation value θe_e1 calculated by the magnetic pole position / speed estimation unit 31 during the execution of the sensorless control process. Then, the magnetic pole position abnormality detection unit 22 generates an abnormality in the magnetic pole position estimated value θe_e1 when the temporal change rate (change speed of θe_e1) of the input magnetic pole position estimated value θe_e1 shows an abnormal change, for example. Detecting that

  Instead of the magnetic pole position estimated value θe_e1 (or in addition to θe_e1), the magnetic angular velocity (or rotational speed estimated value ωr_e1) calculated by the magnetic pole position / speed estimating unit 31 is applied to the magnetic pole position abnormality detecting unit 22. You may make it input.

  In the present embodiment, the γ-axis current command selection switching unit 13 (switch 13) uses the first γ-axis as the actual use γ-axis current command value iγ_c to be input to the voltage command value determination unit 15 when the sensorless control process is executed. The current command value iγ_c1 is selected, and the second γ-axis current command value that is “0” is selected when the pre-startup control process and the fail control process are executed. Similarly, the δ-axis current command selection switching unit 14 (switch 14) uses the first δ-axis current command value iδ_c1 as the actual use δ-axis current command value iδ_c to be input to the voltage command value determination unit 15 when the sensorless control process is executed. When the pre-startup control process and the fail control process are executed, the second δ-axis current command value which is “0” is selected as the actual use δ-axis current command value iδ_c.

  Furthermore, in the present embodiment, the coordinate conversion magnetic pole position selection switching unit 21 (switch 21), when executing the sensorless control process, uses the magnetic pole calculated by the magnetic pole position / velocity estimation unit 31 as the coordinate conversion magnetic pole position θa. The position estimated value θe_e1 is selected, and the simple magnetic pole position estimated value θe_e calculated by the integrator 23 is selected when the pre-startup control process and the fail control process are executed.

  In the following description, as in the first embodiment, the operating position of the switch 13 when the γ-axis current command selection switching unit 13 (switch 13) selects the first γ-axis current command value iγ_c1 as iγ_c. Is the sensorless control position, and the operation position of the switch 13 when the second γ-axis current command value (= 0) is selected as iγ_c is referred to as a pre-startup / fail control position. Similarly, when the δ-axis current command selection switching unit 14 (switch 14) selects the first γ-axis current command value iδ_c1 as iδ_c, the operation position of the switch 14 is the sensorless control position, and the second δ-axis current as iδ_c. When the command value (= 0) is selected, the operation position of the switch 14 is referred to as a pre-start / fail control position. Further, when the coordinate conversion magnetic pole position selection switching unit 21 (switch 21) selects the magnetic pole position estimated value θe_e1 as θa, the operation position of the switch 21 is a sensorless control position, and θa is a magnetic pole position simple estimated value θe_e. The operation position of the switch 21 when selecting is referred to as the pre-startup / fail control position.

  The functional configuration of the control device 30 and the functions of the respective parts other than those described above are the same as those of the control device 2 of the first embodiment.

  Supplementally, in this embodiment, the PDU 3 corresponds to the voltage application means in the present invention, the current sensors 4 and 5 correspond to the current detection means in the present invention, and the magnetic pole position / velocity estimation unit 31 corresponds to the magnetic pole position in the present invention. Corresponds to grasping means. The voltage command value determination unit 15 corresponds to voltage command value determination means in the present invention, the integrator 24 corresponds to integration means in the present invention, and the simple speed estimation unit 23 corresponds to speed estimation means in the present invention. To do. The monitoring means in the present invention is realized by the γ-axis current command selection switching unit 13 (switch 13), the δ-axis current command selection switching unit 14 (switch 14), the simple speed estimation unit 23, and the rotation speed determination unit 25. The In this case, the γ-axis voltage command value vγ_c determined by the voltage command value determination unit 15 in a state where both the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c are held at “0”. A set with the δ-axis voltage command value vδ_c corresponds to the monitoring voltage command value in the present invention. Further, the magnetic pole position abnormality detection unit 22 corresponds to a magnetic pole position abnormality detection unit in the present invention, and the error processing unit 26 corresponds to an error processing execution unit in the present invention.

  Next, the overall control processing of the control device 30 will be described with reference to FIG. FIG. 5 is a flowchart showing the overall control process.

  When a request for starting operation of the electric motor 1 is generated, for example, when the operation power supply is turned on, the control device 30 first operates all the switches 13, 14, and 21 to the pre-start / fail control position. In the state, the pre-startup control process is started (STEP 11).

  In the pre-startup control processing, the above-described processing of the voltage command value determination unit 15 is sequentially executed at a predetermined calculation processing cycle in a state where the switches 13, 14, and 21 are operated to the pre-startup / failure control positions, respectively. Is done. Thereby, a set of the phase voltage command values vu_c, vv_c, and vw_c is sequentially determined. Then, the voltages of the phase voltage command values vu_c, vv_c, vw_c are applied from the PDU 3 to the armature windings of the respective phases of the electric motor 1. Further, in the pre-startup control process, the processes of the simple speed estimation unit 23, the integrator 24, and the rotation speed determination unit 24 are performed in parallel with the determination of the phase voltage command values vu_c, vv_c, and vw_c as described above. It is executed sequentially.

  In this pre-startup control process, the operating positions of the switches 13 and 14 are the pre-startup / failure control positions, so that the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c are respectively steady. Therefore, it is held at “0”. For this reason, in the voltage command value determination unit 15, as in the case of the fail mode control process in the first embodiment, the set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c, and thus the phase voltage command value The set of vu_c, vv_c, and vw_c is determined so that the current flowing through the armature winding of each phase of the electric motor 1 is constantly held at “0”. As a result, the voltage applied from the PDU 3 to the armature winding of each phase is controlled so that the current of the armature winding of each phase of the electric motor 1 becomes “0”.

  The simple speed estimation unit 23 controls the γ-axis voltage command value vγ_c and the δ-axis voltage command value while controlling the armature winding current of each phase of the motor 1 to be “0”. From vδ_c, the electrical angular velocity simple estimated value ωe_e is sequentially calculated at a predetermined calculation processing cycle according to the equation (4a) or (4b). Further, the integrator 24 sequentially integrates the electrical angular velocity simple estimated value ωe_e, and sequentially calculates the magnetic pole position simplified estimated value θe_e. The simple magnetic pole position estimated value θe_e calculated by the integrator 24 in this way is sent to the uvw / γδ coordinate conversion unit 15a and γδ / uvw coordinate conversion unit 15f via the coordinate conversion magnetic pole position selection switching unit 21 (switch 21). Is given as the coordinate conversion magnetic pole position θa. In the present embodiment, a predetermined fixed value (for example, “0”) is used as the initial value of the magnetic pole position simple estimated value θe_e in the integration process of the integrator 24 in the pre-startup control process.

  Thus, in the pre-startup control process, the electrical angular speed simple estimated value ωe_e calculated by the simple speed estimating unit 23 is monitored by the rotational speed determining unit 24, and whether or not the electrical angular speed simple estimated value ωe_e is “0”. Is determined (STEP 12). Here, the entire operation of the control system is stopped before the pre-startup control process is executed. In this state, the rotor of the electric motor 1 may be rotated by an external force applied from the load side. For example, when the electric motor 1 is an electric motor for driving a fan, the rotor of the electric motor 1 may be rotating due to the influence of wind or the like. Thus, even when the entire operation of the control system is stopped, the rotor of the electric motor 1 may be rotating due to the influence of the load state or the like. In the state where the rotor rotates in this way, ωe_e ≠ 0, and therefore the determination result of STEP 12 is negative. In this state, the determination process in STEP 12 is continuously performed.

  If the rotor of the electric motor 1 has not been rotated from the beginning or has stopped rotating, the determination result of STEP 12 becomes affirmative. At this time, in STEP 13, the control device 30 switches the operating position of the switches 13, 14, and 21 from the pre-startup / failure control position to the sensorless control position, and starts the operation of the electric motor 1 by the sensorless control process. Further, the control device 30 monitors the presence / absence of abnormality of the magnetic pole position estimated value θe_e1 by the magnetic pole position abnormality detection unit 22 while executing the sensorless control process (STEP 14).

  In this case, in the sensorless control process, the deviation calculating unit 11, the speed control unit 12, the voltage command value determining unit 15, and the magnetic pole position / speed estimation are performed in a state where the switches 13, 14, and 21 are moved to the sensorless control position. The above-described processing of the unit 31 is sequentially executed at a predetermined calculation processing cycle. Thereby, a set of the phase voltage command values vu_c, vv_c, and vw_c is sequentially determined. The voltages of the phase voltage command values vu_c, vv_c, and vw_c are applied from the PDU 3 to the armature windings of the respective phases of the electric motor 1 as described above, and the energization of the respective armature windings of the electric motor 1 is controlled. The

  In this sensorless control process, since the operating positions of the switches 13 and 14 are sensorless control positions, the actual use γ-axis current command value iγ_c and the actual use δ-axis current command value iδ_c input to the voltage command value determination unit 15. Are the first γ-axis current command value iγ_c1 and the first δ-axis current command value iδ_c1 determined by the speed control unit 12, respectively. Therefore, as in the case of the normal mode control process in the first embodiment, the γ-axis voltage command value vγ_c determined by the γ-axis current control unit 15d and the δ-axis current control unit 15e of the voltage command value determination unit 15 is The set of the δ-axis voltage command value vδ_c, and thus the set of the phase voltage command values vu_c, vv_c, and vw_c, respectively represents the γ-axis current detection value iγ and the δ-axis current detection value iδ, respectively, as the first γ-axis current command value iγ_c1. The first δ-axis current command value iδ_c1 is determined to converge. Accordingly, the energization of the armature windings of each phase of the electric motor 1 is feedback controlled so that the estimated rotational speed value ωr_e1 becomes the speed command value ωr_c.

  In the sensorless control process, in the coordinate conversion process of the uvw / γδ coordinate conversion unit 15 and the γδ / uvw coordinate conversion part 20, the magnetic pole position estimated value θe_e1 calculated by the magnetic pole position / velocity estimation unit 31 is the coordinate conversion magnetic pole. Used as position θa.

  As described above, when the control device 30 performs the sensorless control process, if an abnormality of the magnetic pole position estimated value θe occurs due to a calculation error of the magnetic pole position / velocity estimation unit 31 or the like, this is detected as the magnetic pole position abnormality detection. It is detected by the unit 22 (the determination result in STEP 14 is YES). At this time, in STEP 15, the operation positions of the switches 13, 14, and 21 are switched from the sensorless control position to the pre-startup / fail control position, respectively, and the fail control process is started.

  This fail control process is executed in the same manner as the fail mode control process of the first embodiment. That is, in the state where the switches 13, 14, 21 are operated to the pre-startup / failure control position, the voltage command value determination unit 15, the simple speed estimation, as described regarding the fail mode control process of the first embodiment. The processing of the unit 23 and the integrator 24 is sequentially executed at a predetermined calculation processing cycle. Therefore, while the applied voltage from the PDU 3 to the armature winding of each phase is controlled so that the current of the armature winding of each phase of the electric motor 1 becomes “0”, the electrical angular velocity simple estimated value ωe_e, Are simply calculated by the simple speed estimation unit 23 and the integrator 24, respectively. In the integration process of the integrator 24 in the fail control process in the present embodiment, immediately before the occurrence of the abnormality of the magnetic pole position estimated value θe_e1 is detected by the magnetic pole position abnormality detection unit 22 (immediately before the start of the fail control process). The magnetic pole position estimated value θe_e1 is set as the initial value of the magnetic pole position simple estimated value θe_e. Except for this point, the processing of the voltage command value determination unit 15, the simple speed estimation unit 23, and the integrator 24 in the fail control process of the present embodiment is the same as the fail mode control process of the first embodiment.

  While executing the fail control process as described above, the electrical angular speed simple estimated value ωe_e calculated by the simple speed estimating unit 23 is monitored by the rotational speed determining unit 24, and the electrical angular speed simple estimated value ωe_e becomes “0”. It is determined whether or not (STEP 16). At this time, in a state where the rotor of the electric motor 1 is rotating, ωe_e ≠ 0, so the determination result in STEP 16 is negative. In this state, the determination process in STEP 16 is continuously performed.

  Thereafter, when the rotation of the rotor of the electric motor 1 is stopped, the determination result in STEP 16 becomes affirmative. At this time, the error processing unit 25 executes predetermined error processing (STEP 17). This error processing is the same as in the first embodiment. That is, the error processing unit 25 cuts off the supply of power from the DC power source to the PDU 3 and further executes a reset process of the control system of the electric motor 1.

  The above is the overall control processing of the control device 30.

  In this embodiment, before starting the operation of the electric motor 1 by the sensorless control process, the control device 30 first holds the current of the armature winding of each phase of the electric motor 1 at “0” by the pre-startup control process. As described above, the set of the γ-axis voltage command value vγ_c and the δ-axis voltage command value vδ_c that defines the voltage applied from the PDU 3 to the armature winding, and thus the phase voltage command values vu_c, vv_c, and vw_c are determined. Then, while determining vγ_c and vδ_c in this way, the control device 30 executes the calculation process of the simple speed estimation unit 23 and the integrator 24.

  At this time, calculation processing of the simple speed estimation unit 23 is performed while controlling the applied voltage of the armature winding of the electric motor 1 so that the current of the armature winding of each phase of the electric motor 1 is kept at “0”. Therefore, as in the case of the fail mode control process of the first embodiment, the electrical angular speed simple estimated value ωe_e having sufficient reliability as the estimated value of the actual electrical angular speed of the rotor of the electric motor 1 can be calculated. Therefore, the rotational motion state of the rotor before the start of operation of the electric motor 1 can be grasped from the electric angular velocity simple estimated value ωe_e.

  In this case, the simple magnetic pole position estimated value θe_e calculated by the integrator 24 in the pre-startup control process changes in synchronization with the rotation period of the rotor. For this reason, as in the case of the fail mode control process of the first embodiment, the voltage applied from the PDU 3 to the armature winding of each phase of the electric motor 1 is generated in the armature winding relatively quickly. It becomes synchronized with the induced voltage. As a result, in the pre-startup control process, the current of the armature winding of each phase of the electric motor 1 can be quickly converged to “0” while suppressing frequent fluctuations. For this reason, the current of the armature winding of each phase of the electric motor 1 can be smoothly and quickly converged to “0”.

  As described above, since the current of the armature winding of each phase of the electric motor 1 can be quickly converged to “0”, even if the rotor is rotating before the operation of the electric motor 1 is started, the reliability can be improved. It is possible to quickly realize a state in which the simple electrical angular velocity simple estimated value ωe_e can be calculated by the simple velocity estimating unit 23. That is, the electrical angular velocity of the rotor of the electric motor 1 can be quickly estimated with high reliability before the operation of the electric motor 1 is started.

  Then, after confirming that the rotation of the rotor of the electric motor 1 is stopped by the electric angular velocity simple estimated value ωe_e, the control device 30 starts operation control of the electric motor 1 by the sensorless control process. For this reason, the reliability of the magnetic pole position estimated value θe_e1 and the rotational speed estimated value ωr_e1 calculated by the magnetic pole position / speed estimating unit 31 can be improved. As a result, the desired driving | operation of the electric motor 1 can be performed stably and appropriately.

  Further, in the present embodiment, when the occurrence of an abnormality of the magnetic pole position estimated value θe_e1 is detected by the magnetic pole position abnormality detection unit 22 during the operation of the electric motor 1 by the sensorless control process, the control device 30 performs the first embodiment. Fail control processing similar to the fail mode control processing of the embodiment is executed. For this reason, as in the first embodiment, after the occurrence of the abnormality of the magnetic pole position estimated value θe_e1, the electric angular velocity simple estimated value ωe_e having high reliability is calculated as an index representing the rotational speed of the rotor of the electric motor 1 immediately. However, it is possible to recognize a state in which the rotation of the rotor is stopped (a state in which the electrical angular velocity simple estimated value ωe_e is “0”). When the simple electrical angular velocity estimated value ωe_e becomes “0”, the error processing unit 25 executes error processing to cut off the supply of power to the PDU 3, so that the induced voltage generated in the motor 1 As a result, it is possible to avoid damage to the drive circuit of the PDU 3 or the like.

  In the present embodiment, the magnetic pole position estimated value θe_e1 immediately before the occurrence of the abnormality of the magnetic pole position estimated value θe_e1 is detected (immediately before the start of the fail control process) is set as the initial value of the simple magnetic pole position estimated value θe_e. However, the initial value of the magnetic pole position simple estimated value θe_e may be set to a fixed value such as “0”. However, in order to converge the current of the armature winding of each phase of the motor 1 to “0” as quickly as possible, the initial value of the magnetic pole position simple estimated value θe_e is detected as the occurrence of an abnormality in the magnetic pole position estimated value θe_e1. It is advantageous to set the magnetic pole position estimated value θe_e1 immediately before.

  In each of the embodiments described above, the system for controlling the rotational speed of the rotor of the electric motor 1 to the speed command value ωr_c has been described as an example. However, the output torque of the electric motor 1 is controlled to the target torque (torque command value). You may make it a system to do.

In each of the embodiments described above, from the voltage command values (γ-axis voltage command value vγ_c and δ-axis voltage command value vδ_c) in a state where the current of the armature winding of the electric motor 1 is controlled to “0”, the above equation ( Whether or not the rotation of the rotor has stopped is determined based on whether or not the electrical angular velocity simple estimated value ωe_e calculated by 4a) or (4b) is “0”, the magnitude of the voltage command value (the above formula ( Whether or not the rotation of the rotor has stopped may be determined based on whether or not | v _γδ |) calculated in step 4c) is “0”.

Further, in each of the embodiments, when the electrical angular velocity simple estimated value ωe_e becomes “0”, it is determined that the rotation of the rotor has stopped. However, the electrical angular velocity simple estimated value ωe_e is sufficiently “0”. (When the absolute value of ωe_e is smaller than a predetermined value), or the voltage command value magnitude | v _γδ | in the γδ coordinate system is sufficiently close to “0”. When the value reaches the value (when | v _γδ | becomes a small predetermined value or less), it may be determined that the rotation of the rotor has stopped.

The block diagram which shows the whole structure of the control system of the synchronous motor in 1st Embodiment of this invention. The figure which shows the relationship between dq coordinate system and (gamma) delta coordinate system. The flowchart which shows the whole control processing of the control apparatus of 1st Embodiment. The block diagram which shows the whole structure of the control system of the synchronous motor in 2nd Embodiment of this invention. The flowchart which shows the whole control processing of the control apparatus of 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Synchronous motor, 3 ... Power drive unit (voltage application means), 4, 5 ... Current sensor (current detection means), 6 ... Magnetic pole position sensor (magnetic pole position grasping means), 13 ... γ-axis current command selection switching Part (monitoring means), 14 ... δ-axis current command selection switching part (monitoring means), 15 ... voltage command value determining part (voltage command value determining means), 22 ... magnetic pole position abnormality detecting part (magnetic pole position abnormality detecting means), 23 ... Simple speed estimation unit (speed estimation means, monitoring means), 24 ... integrator (integration means), 25 ... rotational speed judgment section (monitoring means), 26 ... error processing section (error processing execution means), 31 ... magnetic pole Position / velocity estimation unit (magnetic pole position grasping means).

Claims (5)

An apparatus for monitoring the rotational motion state of a rotor in a synchronous motor having a permanent magnet in the rotor,
Current detecting means for detecting a current flowing in the armature winding of the synchronous motor;
A current command value, which is a target value of the current of the armature winding, and a current detection value of the armature winding indicated by the output of the current detection means are input, and the deviation between the current command value and the current detection value Voltage command value determining means for determining a voltage command value that is a target value of the voltage applied to the armature winding so as to converge to "0";
Voltage applying means for applying a voltage to the armature winding according to the determined voltage command value;
The current command value to be input to the voltage command value determining means is held at “0” and the voltage command value is determined in the held state under a condition predetermined as a situation in which the rotational motion state of the rotor is to be monitored. A rotor rotation monitoring device for a synchronous motor, comprising: monitoring means for monitoring the rotational motion state of the rotor based on a monitoring voltage command value which is a voltage command value determined by the means.   2. The rotor rotation monitoring device for a synchronous motor according to claim 1, wherein speed estimation means for estimating an electrical angular speed of the rotor from the monitoring voltage command value, and an integrated value of the electrical angular speed estimated by the speed estimation means The voltage command value determining means, wherein the voltage command value determining means is the magnetic pole position determined by the integrating means while the current command value is held at "0" by the monitoring means. A rotor rotation monitoring device for a synchronous motor, wherein the voltage command value is determined by executing vector control arithmetic processing using an estimated value. The rotor rotation monitoring device according to claim 1, magnetic pole position grasping means for detecting or estimating the magnetic pole position of the rotor, and magnetic pole position abnormality for detecting whether or not the magnetic pole position is detected or estimated by the magnetic pole position grasping means A vector control using a magnetic pole position detected or estimated by the magnetic pole position grasping means when the synchronous motor is operated in a state where the occurrence of the abnormality is not detected by the magnetic pole position abnormality detection means. A control system for a synchronous motor configured to determine the voltage command value by causing the voltage command value determining means to execute the calculation process of:
The monitoring means, when the occurrence of the abnormality is detected by the magnetic pole position abnormality detection means, assumes that the rotational motion state of the rotor is to be monitored and the current command input to the voltage command value determination means A means for holding the value at “0” and determining whether or not the rotation of the rotor is stopped based on the monitoring voltage command value;
After the occurrence of the abnormality is detected by the magnetic pole position abnormality detection means, the supply of power to the voltage application means is cut off when the monitoring means determines that the rotation of the rotor is stopped. A control system for a synchronous motor, comprising error processing execution means for executing predetermined error processing including processing. In the synchronous motor control system according to claim 3,
Speed estimation means for estimating the electrical angular speed of the rotor from the monitoring voltage command value; and integration means for obtaining an integral value of the electrical angular speed estimated by the speed estimation means as a magnetic pole position estimation value of the rotor,
The voltage command value determining means executes a vector control calculation process using the magnetic pole position estimated value obtained by the integrating means in a state where the current command value is held at “0” by the monitoring means. Means for determining the voltage command value,
The integrating means uses the magnetic pole position estimated value as the initial value of the integrated value, with the magnetic pole position detected or estimated by the magnetic pole position grasping means immediately before the occurrence of the abnormality being detected by the magnetic pole position abnormality detecting means. A control system for a synchronous motor, characterized in that it is a means for obtaining. The rotor rotation monitoring device according to claim 1 or 2, wherein when the synchronous motor is operated, by causing the voltage command value determination means to execute sensorless control calculation processing including estimation processing of the magnetic pole position of the rotor, In the synchronous motor control system that determines the voltage command value,
The monitoring means determines that the current command value input to the voltage command value determining means is “0”, assuming that the rotational motion state of the rotor is to be monitored when a request to start operation of the synchronous motor occurs. ”And a means for determining whether or not the rotation of the rotor is stopped based on the monitoring voltage command value,
A control system for a synchronous motor, wherein the operation of the synchronous motor is started when the monitoring means determines that the rotation of the rotor is stopped.

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