JP2006157994A - Drive method and drive controller for brushless and sensorless dc motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drive method and a drive controller which are so arranged as to smoothly and favorably perform the process from the start to the sensorless drive of a rotor by simply estimating the rotor magnetic pole position of a brushless and sensorless DC motor. <P>SOLUTION: In this drive method, the voltage for detection of the magnetic pole position of a rotor on a level that the rotor 2a, where permanent magnets are arranged around, does not rotate is applied to the armature winding of each energization phase of the brushless and sensorless DC motor 2 in order for a specified time, according to a specified energization pattern, and the magnitude of the armature current flowing to the armature winding of each energization phase is detected for each energization phase, based on the magnetic flux flowing between the magnetic pole of the stator iron core where armature winding of each energization phase is wound and the rotor 2a by the application of the voltage for detection of the magnetic pole position of the rotor, and the energization phase of the armature winding where the maximum current flows is selected, and the selected energization phase is estimated as the magnetic pole position of the rotor, and necessary starting voltage is applied to the armature winding of the next phase of the energization phase estimated as the rotor magnetic pole position so as to drive the rotor 2a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an improvement of a brushless and sensorless DC motor, and an object of the present invention is to quickly and reliably estimate a rotor magnetic pole position at which the rotor starts to drive the motor smoothly and satisfactorily. The present invention relates to a driving method and a driving control device for a brushless / sensorless DC motor.

  Conventionally, in a brushless / sensorless DC motor, since the rotor magnetic pole position is unknown, it is necessary to fix the rotor magnetic pole position at a predetermined rotation start position at the time of startup. For this reason, for example, when the rotor does not exist at the normal rotation start position, the rotor is rotated to the rotation start position and fixed by the magnetic field generated by energizing the armature winding.

  However, depending on the rotational position of the rotor while the rotation is stopped, even if a fixed magnetic field is applied, no torque is generated, or even if torque is generated, the static friction resistance at the start of rotor rotation If it is small, it is difficult to reliably fix the rotor at the rotation start position. For this reason, even if the rotation of the rotor is started by the fixed magnetic field of the armature winding, the rotation of the rotor is unstable and often causes a step-out.

  In view of the above-described problems, when a brushless / sensorless DC motor is started, it is forcibly commutated at a preset frequency and voltage as a synchronous motor or a stepping motor, and a speed electromotive force sufficient for magnetic field position detection is generated. While maintaining the balance with the load to the rotation region, it was gradually accelerated. However, in such a motor drive circuit, the acceleration time after starting the motor is inevitably long, and it is difficult to start and operate at low rotation and high torque.

  The applicant of the present application invented a sensorless drive circuit for a brushless DC motor described in Japanese Patent Laid-Open No. 9-37586 shown as Patent Document 1. Such a motor drive circuit pays attention to the armature current waveform of each phase of the motor as shown in FIG. 4 of Patent Document 1, and the second current out of the two significant current increase regions appearing in the energized region of each phase. The increased region is detected, this is determined as the commutation timing, and commutation control is performed.

JP-A-9-37586

  However, the detection of the second current increase region is performed based on the fact that the armature current of the motor is a predetermined multiple (for example, 1.2 times) of the average value of the armature current. As a result, an amplifier for amplifying the average value of the armature currents by a predetermined factor must be provided, which increases the manufacturing cost of the sensorless drive circuit.

  Further, the sensorless driving circuit disclosed in Japanese Patent Laid-Open No. 9-37586 includes a start compensation circuit for smoothly starting the brushless motor, and the start compensation circuit functions only at the start. In addition, since the circuit that functions only at the time of starting is provided independently, there is a problem that the cost of the entire brushless motor driving circuit increases.

  In view of the above-described problems, the present invention realizes smooth and good motor start-up smoothly and satisfactorily even when the rotor magnetic pole position at the time of starting the rotor is unknown, and commutation operation according to the rotor magnetic pole position. It is an object of the present invention to provide a brushless and sensorless DC motor driving method and a driving control device that can realize sensorless start-up of a motor efficiently and reliably.

  According to the first aspect of the present invention, an inverter circuit that energizes an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and the brushless sensorless DC motor is rotated by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate The magnetic pole position detection voltage is sequentially applied for a predetermined time, and the rotor magnetic pole position detection voltage is applied between the stator core magnetic poles and the rotor wound with the armature windings of the respective energized phases. Based on the flowing magnetic flux, the armature current flowing through the armature winding of each energized phase is detected for each energized phase and the energized phase of the armature winding through which the maximum current flows is selected. The selected energized phase is estimated as the rotor magnetic pole position, and the rotor is started by supplying the required starting voltage to the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position. It is characterized by that.

  According to a second aspect of the present invention, there is provided an inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and the brushless sensorless DC motor is rotated by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate The magnetic pole position detection voltage is sequentially applied for a predetermined time, and the rotor magnetic pole position detection voltage is applied between the stator core magnetic poles and the rotor wound with the armature windings of the respective energized phases. Based on the flowing magnetic flux, the armature current flowing through the armature winding of each energized phase is detected for each energized phase and the energized phase of the armature winding through which the maximum current flows is selected. The selected energized phase is estimated as the rotor magnetic pole position, and the armature winding of each energized phase is preliminarily applied in accordance with a predetermined energization pattern from the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position. The rotor is driven by energizing the energizing time while decreasing the energizing time for a while for a predetermined energizing time after energizing the predetermined start-up voltage set to a predetermined energizing time.

  According to a third aspect of the present invention, there is provided an inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and the brushless sensorless DC motor is rotated by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate The magnetic pole position detection voltage is sequentially applied for a predetermined time, and the rotor magnetic pole position detection voltage is applied between the stator core magnetic poles and the rotor wound with the armature windings of the respective energized phases. Based on the flowing magnetic flux, the armature current flowing through the armature winding of each energized phase is detected for each energized phase and the energized phase of the armature winding through which the maximum current flows is selected. The selected energized phase is estimated as the rotor magnetic pole position, and the armature winding of each energized phase is preliminarily applied in accordance with a predetermined energization pattern from the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position. After energizing a predetermined start-up voltage set to a predetermined energization time, the energization time is decreased for each energization phase for a while and the rotor is started by energization. When it is determined whether or not the rotation speed set in advance has been reached and the rotation speed has reached the set rotation speed, the armature current flowing through the armature winding of the current-carrying phase is ½ of the energization time. When the armature current detected after the elapse of time reaches a predetermined multiple, the commutation command is output and the energized phase is switched to switch the start of the rotor to the sensorless drive and drive the rotor. It is characterized by that.

  According to a fourth aspect of the present invention, there is provided an inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and the brushless sensorless DC motor is rotated by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate A rotor starting position detector that sequentially applies a voltage for detecting a magnetic pole position, a current detection circuit that detects an armature current flowing through the armature winding of each energized phase for each energized phase, and each energized phase Based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position applied to the armature winding of The armature current flowing through the armature winding of each energized phase is detected by the current detection circuit, and the magnitude of the armature current is compared with each armature winding of each energized phase and the maximum current flows A rotor magnetic pole position estimating means for selecting an energized phase of the rotor winding and estimating the energized phase as a rotor magnetic pole position; and an armature winding positioned in the next phase of the energized phase estimated as the rotor magnetic pole position. It is characterized by comprising a rotor starting part for starting a rotor by energizing a predetermined starting voltage.

  According to a fifth aspect of the present invention, there is provided an inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and the brushless sensorless DC motor is rotated by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate A rotor starting position detector that sequentially applies a voltage for detecting a magnetic pole position, a current detection circuit that detects an armature current flowing through the armature winding of each energized phase for each energized phase, and each energized phase Based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position applied to the armature winding of The armature current flowing through the armature winding of each energized phase is detected by the current detection circuit, and the magnitude of the armature current is compared with each armature winding of each energized phase and the maximum current flows A rotor magnetic pole position estimating means for selecting an energized phase of the rotor winding and estimating the energized phase as a rotor magnetic pole position, and estimating the selected energized phase as a rotor magnetic pole position to estimate the rotor magnetic pole position. After energizing a predetermined start-up voltage preset in advance to each armature winding of each energized phase in sequence according to a predetermined energization pattern from the armature winding of the next phase of the energized phase, It is characterized by comprising a rotor starting portion that is energized while being decreased for each energized phase for a while.

  According to a sixth aspect of the present invention, there is provided an inverter circuit for energizing an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and rotating the brushless sensorless DC motor by causing commutation by the inverter circuit. In a drive control system for a brushless / sensorless DC motor configured to include a drive control circuit for rotating the rotor with a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern so as not to rotate A rotor starting position detector that sequentially applies a voltage for detecting a magnetic pole position, a current detection circuit that detects an armature current flowing through the armature winding of each energized phase for each energized phase, and each energized phase Based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position applied to the armature winding of The armature current flowing through the armature winding of each energized phase is detected by the current detection circuit, and the magnitude of the armature current is compared with each armature winding of each energized phase and the maximum current flows A rotor magnetic pole position estimating means for selecting an energized phase of the rotor winding and estimating the energized phase as a rotor magnetic pole position, and estimating the selected energized phase as a rotor magnetic pole position to estimate the rotor magnetic pole position. After energizing a predetermined start-up voltage preset in advance to each armature winding of each energized phase in sequence according to a predetermined energization pattern from the armature winding of the next phase of the energized phase, A rotor starting unit that is energized while decreasing for each energizing phase, and further, it is determined whether or not the rotational speed has reached a predetermined set rotational speed by starting the rotor and reaches the set rotational speed. The current flowing through the armature winding of the current-carrying phase A sensorless drive unit that outputs a commutation command and switches the energized phase to drive the rotor sensorlessly when the current reaches a predetermined multiple of the armature current detected after ½ hour of the energization time has elapsed. A drive control apparatus for a brushless / sensorless DC motor.

  According to a seventh aspect of the present invention, in the drive control device for a brushless / sensorless DC motor according to the fourth, fifth, and sixth aspects, the starting position detecting unit applies a voltage at which the rotor does not rotate to each armature of each energized phase. A starting position detecting voltage applying means for applying to the winding; and a voltage applying phase switching means for sequentially applying the starting position detecting voltage to the armature winding of each energized phase according to a predetermined energizing pattern. It is characterized by that.

  According to an eighth aspect of the present invention, in the drive control device for a brushless sensorless DC motor according to the fourth, fifth, and sixth aspects, the rotor magnetic pole position estimating means is an armature of each energized phase detected by the current detection circuit. Comparing the armature currents flowing through the windings and selecting a current-carrying phase through which the maximum armature current flows, and a function for estimating the selected current-carrying phase as a rotor magnetic pole position And

  According to a ninth aspect of the present invention, in the drive control device for a brushless sensorless DC motor according to the fourth, fifth, and sixth aspects, the rotor starting portion is a rotor magnetic pole position estimated by the rotor magnetic pole position estimating means. A starting voltage energizing phase setting means for setting the energizing phase positioned next to the energizing phase as an energizing phase that first energizes the starting voltage, and a starting voltage that energizes the set energizing phase with a predetermined starting voltage It is characterized by comprising an energizing means.

  A tenth aspect of the present invention is the brushless / sensorless DC motor drive control apparatus according to the sixth aspect, wherein the rotation speed of the sensorless drive unit reaches a preset rotation speed by starting the rotor. If the motor reaches a predetermined number of revolutions, the sensorless drive switching means for switching the rotor activation to the sensorless drive, and the armature current flowing through the armature winding in the energized phase when the sensorless drive is switched Comprising a commutation command means for outputting a commutation command and switching the energized phase when the armature current reaches a predetermined multiple of the armature current detected after ½ hour of the energization time has elapsed. It is characterized by.

  According to the first aspect of the present invention, when starting the rotor of the brushless / sensorless DC motor, first, the rotor magnetic pole position detection voltage (for example, the rotor is not rotated in the multi-phase armature winding) (for example, , AC voltage 12V) is sequentially applied for a predetermined time according to a preset energization pattern, and the armature winding is detected by detecting the magnitude of the armature current flowing in the armature winding of each phase to which the voltage is applied. The energized phase through which the maximum armature current flows is selected, the rotor magnetic pole position is estimated from the selected energized phase, and the rotor magnetic pole position is estimated from the armature winding located in the next phase of the estimated energized phase. Since the rotor is started by sequentially energizing the starting voltage (for example, AC voltage 5V) for starting the rotor for each energized phase, the rotor magnetic pole position of the brushless sensorless DC motor swings the rotor. Let Without, it is possible to energize the activation voltage estimated almost instantly to the armature winding of a predetermined conduction phase, this type motor quickly, and can be started smoothly. In addition, in estimating the rotor magnetic pole position, if a voltage for detecting the rotor magnetic pole position is sequentially applied to the armature winding of each energized phase according to a predetermined energization pattern, the armature winding of each energized phase is wound. Focusing on the fact that the armature current flowing in the armature winding of each phase changes slightly based on the amount of magnetic flux flowing between the magnetic pole and rotor of the stator core, the maximum armature current The energized phase in which the flowing armature winding is detected (the repulsive force due to energization is small between the magnetic pole of the stator core where the armature winding of the energized phase in which the maximum armature current flows exists and the rotor) As a result of the armature current flowing in the armature winding is larger than that of the other phase (the energized phase in which a strong repulsive force acts between the magnetic pole and the rotor), the stator core magnetic pole and rotor During this time, the magnetic flux flows well and the rotor rotates smoothly. It is sufficient estimate will and the fixed magnetic field is generated to) case is a rotor magnetic pole position, it is convenient can be done almost instantaneously estimated rotor magnetic pole position. In addition, when the starting voltage for starting the rotor is energized, the starting voltage is supplied from the armature winding existing in the next phase of the energized phase estimated as the rotor magnetic pole position. This can be started smoothly and satisfactorily without moving the rotor to the position estimated as the rotor magnetic pole position as before. Furthermore, the energization of the starting voltage is performed from the next phase of the energized phase estimated as the rotor magnetic pole position, the magnetic flux flowing between the stator iron core and the rotor is the same as the energized phase estimated as the rotor magnetic pole position. Paying attention to the point that it is the next most frequently flowing position, by energizing the starting voltage to each phase armature winding sequentially from this energized phase of the next phase, the rotor moves sequentially to the optimal rotating magnetic pole position. This type of motor can be started smoothly, satisfactorily and quickly without jerky during movement, swinging in the left-right rotation direction, or applying a fixed magnetic field to the armature winding. Start-up with low rotation and high torque can be performed smoothly.

  In the invention according to claim 2, as described above, the armature windings of the respective phases are changed from the armature windings located in the next phase of the energized phase estimated as the rotor magnetic pole position of the rotor according to a predetermined energization pattern. When energizing the start-up voltage, the rotor is started by energizing the start-up voltage while decreasing the start-up voltage sequentially for each energized phase for a predetermined energization time. Even if the energization time is reduced, the start-up can be performed smoothly by the initial energization. Therefore, even if the energization time of the start-up voltage is reduced after the rotor is started, the start-up (rotation) of the rotor is continued well. As a result, the startup of the brushless / sensorless DC motor can be performed quickly, reliably and energy-saving, which is convenient. In addition, when starting the rotor, the energization phase of the starting voltage is set as described above, so that the rotor itself swings in the left-right direction as in the past with energization of the starting voltage. Since it can be started in a stable state, it can be started smoothly and satisfactorily without causing a step-out of the brushless / sensorless DC motor or causing insufficient torque.

  According to a third aspect of the present invention, in the first and second aspects of the present invention, the rotor magnetic pole position of the rotor is estimated and the armature winding of the next phase of the energized phase estimated to be the rotor magnetic pole position To start the rotor by sequentially energizing the armature winding of each energized phase with a predetermined energization pattern, and when the number of rotations reaches the set number of rotations, When the armature current flowing in the child winding reaches a predetermined multiple (for example, 1.3 times) of the detected current after ½ hour of the energization time of the starting voltage passed through the armature winding, Since the commutation command for switching the energization to the energized phase of the next phase is output, the rotor can be reliably started at the time of starting, and the switching from the start of the rotor to the sensorless drive can be performed. As mentioned above, the speed of the rotor is taken into account quickly. Certainly, and, since it is possible to easily switch, for example, Toka pump speed of rise is required, a motor for driving source of the vacuum cleaner or the like can be easily realized.

  According to a fourth aspect of the present invention, a starting position detector that sequentially applies a voltage for detecting the rotor magnetic pole position so that the rotor does not rotate in accordance with a predetermined energization pattern to the armature winding of each energized phase, and the rotation The armature current flowing through the armature winding of each phase is detected by applying the child starting position detection voltage, and the energized phase in which the maximum current flows is selected from the detected armature currents, and the energized phase is selected as the rotor. The rotor magnetic pole position estimating means for estimating the magnetic pole position, and a predetermined starting voltage are sequentially applied to the armature winding of each energized phase from the rotor magnetic pole position and the armature winding positioned next to the estimated energized phase. Since the rotor starting unit in the brushless / sensorless DC motor is configured by the rotor starting unit that starts the rotor, the rotation of the rotor is started as before when starting this type of motor. When the position is unknown, it is completely different from the case where the armature winding is started by rotating the rotor to the rotation start position by applying a fixed magnetic field, and the present invention swings the rotor, There is no need to set the rotor magnetic pole position by rotating it, and the rotor magnetic pole position detection voltage is applied to the armature winding of each energized phase wound around the stator core according to a predetermined energization pattern. As a result, depending on the amount of magnetic flux flowing between the magnetic pole of the stator core around which the armature winding is wound and the rotor, the armature current flowing in the armature winding of each phase is large or small. Thus, the energized phase of the armature winding through which the maximum current flows among the armature currents flowing through the armature winding is estimated as the rotor magnetic pole position, and the starting voltage for starting the rotor is defined as the rotor magnetic pole position. Predetermined energization from the armature winding of the next phase of the estimated energization phase Since the rotor is activated by energizing according to the turn, the rotor does not oscillate at the time of activation (this energized phase is between the magnetic pole of the stator core and the rotor as described above. Therefore, it is possible to start up smoothly and quickly and reliably.

  According to a fifth aspect of the present invention, a starting position detecting section that sequentially applies a voltage for detecting a rotor magnetic pole position to such an extent that the rotor does not rotate in accordance with a predetermined energization pattern to a plurality of armature windings, and the rotor The armature current flowing in the armature winding of each phase is detected by applying the starting position detection voltage, and the energized phase in which the maximum current flows is selected from the detected armature currents, and the energized phase is selected as the rotor magnetic pole. A rotor magnetic pole position estimating means for estimating the position, and a predetermined starting voltage for each armature winding of each energized phase sequentially from the armature winding positioned in the next phase of the energized phase estimated as the rotor magnetic pole position The rotor starting unit in the brushless / sensorless DC motor is configured by the rotor starting unit that starts the rotor by energizing the energized phase by reducing the energized phase for a certain period of time. In operation, the energized phase for energizing the starting voltage is estimated by the rotor magnetic pole position estimating means. As a result, the starting voltage gradually increases the energizing time for the starting voltage for smoothly starting the rotor, and the required energizing time. Even if the armature windings of the phases are energized, each energized phase is energized according to a predetermined energization pattern, so that the start-up can be maintained satisfactorily without swinging the rotor. Since it is possible to start up the rotor, it is possible to start up the rotor efficiently with low power by a simple circuit configuration, which is convenient.

  According to a sixth aspect of the present invention, a starting position detector for sequentially applying a rotor magnetic pole position detection voltage to a degree that the rotor does not rotate in accordance with a predetermined energization pattern to a plurality of armature windings, and the rotor The armature current flowing through the armature winding of each energized phase is detected by applying the starting position detection voltage, and the energized phase through which the maximum current flows is selected from the detected armature currents, and the energized phase is selected as the rotor. The rotor magnetic pole position estimating means for estimating the magnetic pole position, and the armature winding positioned in the next phase of the energized phase estimated as the rotor magnetic pole position, and sequentially applying a predetermined starting voltage to the armature winding of each energized phase A rotor starting unit that starts the rotor by energizing the energized phase for a period of time less than the energizing time, and when the rotor reaches a predetermined number of rotations by starting the rotor, the rotor Sensor-less drive Since the sensorless drive unit for switching is used, switching from the start-up of this type of motor to sensorless drive and the start of the rotor to maintain the sensorless drive and the presence of sensorless drive means, the rotor Without starting the estimation of the magnetic pole position at the time of start-up as usual and simply starting the rotor by estimating the rotor magnetic pole position quickly and easily at the position of the rotor that has stopped rotating. After the start-up, when a predetermined number of revolutions is reached, sensorless driving (that is, a predetermined value of the armature current value detected after the armature current flowing in the armature winding has passed 1/2 hour of the immediately preceding energization time) (The commutation is performed when the current reaches 1.3 times), and the drive of the brushless / sensorless DC motor is caused to oscillate / step out. It not, it is possible to ensure a smooth-good, has a feature that can be satisfactorily used as a driving source of the fast pump Toka vacuum cleaner, such as the rise.

  According to the seventh aspect of the present invention, the starting position detecting unit includes a starting position detecting voltage applying unit that applies a voltage that does not rotate the rotor, and the starting position detecting voltage is supplied to the starting position by a predetermined energization pattern. Since the voltage application phase switching means that sequentially applies to the phase, the voltage applied to the energized phase for estimating the magnetic pole position of the rotor is applied according to a predetermined energization pattern so that the rotor does not rotate. As a result, the voltage applied to each energized phase can be applied smoothly and reliably without swinging the rotor. As a result, the current flowing in the armature winding of each energized phase can be accurately detected. It becomes possible.

  In the invention according to claim 8, the rotor magnetic pole position estimating means has the function of detecting the armature current flowing in the armature winding of each energized phase and determining the armature winding through which the maximum current flows. This is convenient because the energized phase is constituted by the function of estimating the rotor magnetic pole position as the rotor magnetic pole position, and the rotor magnetic pole position can be estimated quickly and reliably by a simple function.

  According to the ninth aspect of the present invention, the rotor starting unit includes a starting voltage energized phase setting means for setting an energized phase for initially energizing the starting voltage when starting the rotor, the set energized phase and the predetermined phase. Since the starting voltage energizing means for energizing the starting voltage is configured in advance, the energizing phase for energizing the starting voltage is always set in advance when starting the rotor. This is convenient because it can be started smoothly without rocking or stepping out.

  In a tenth aspect of the invention, the sensorless drive unit is switched to sensorless drive and sensorless switching drive means for switching the rotor to sensorless drive when the rotor is activated and its rotational speed reaches a predetermined rotational speed. When the armature current flowing in the armature winding of that phase reaches a predetermined multiple (1.3 times) of the armature current detected after ½ hour of the energization time has elapsed, a commutation command is output. Since the rotor is configured by the flow command means, the rotor is switched from the start-up to the sensorless drive because the rotation speed at the start-up is a predetermined rotation speed, that is, the electric current flowing in the armature winding by the current detection means. Since it is possible to switch to sensorless driving when the child current can be detected, switching from starting the rotor to sensorless driving and maintaining sensorless driving is smooth by a combination of simple means. Therefore, the brushless and sensorless DC motor can be driven smoothly and satisfactorily by simple means without using special rotor magnetic pole position detection means or means for holding the rotor at a predetermined rotation start position. Convenient to do.

  Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 is a block diagram of a drive control device 1 for a brushless / sensorless DC motor shown as a preferred embodiment of the present invention. The drive control device 1 is, for example, various electric devices such as a pump drive source and an air conditioner. A PM brushless motor 2 described as an embodiment of the present invention for driving a fan attached to a motor is used as a drive control device 1 for sensorless driving. The PM brushless motor 2 to be driven includes a rotor having a permanent magnet field and a stator formed by winding a three-phase armature winding (electromagnetic winding) around a stator core. A surface magnet type brushless motor (synchronous motor) configured. In an outer rotor type motor having a field as a stator and an armature winding in a rotor, or an IPM (Interior Permanent Magnet) motor using an embedded magnet type rotor, It is also possible to use the drive control device 1.

  The drive control device 1 is roughly divided in FIG. 1. The AC / DC conversion circuit 3, the inverter circuit 4, the current detection circuit 5, the starting position detection unit 6, the rotor magnetic pole position estimation means 7, the rotation A child starting unit 8, a sensorless driving unit 9, a three-phase inverter control means 10, a sensorless driving stopping unit 11, and a constant voltage power supply circuit 12 are roughly configured.

  Next, details of each component of the drive control device 1 will be described. First, the AC / DC conversion circuit 3 is a converter (power supply device) that converts an AC power supply (for example, commercial power supply AC100V) into a DC power supply (DC140V). The inverter circuit 4 includes bipolar transistors U, V, W, x, y, and z and rectifier elements D1 to D6, and drives the PM brushless motor 2. In the inverter circuit 4, a transistor connected to the P side of the DC / AC conversion circuit 3 is referred to as an upper arm portion 4a, and a transistor connected to the N side is referred to as a lower arm portion 4b.

  In the starting position detector 6, the rotor 2 a shown in the example in the case of a two-pole permanent magnet in each armature winding of each energized phase (U, V, W phase) of the PM brushless motor 2 does not rotate. A voltage applying means 6a for applying a voltage for detecting the rotor magnetic pole position (for example, an AC voltage of 12V) from the output terminal of the inverter circuit 4, and a voltage for detecting the rotor magnetic pole position (hereinafter referred to as detecting) The voltage application phase switching means 6b sets the order of applying the voltage to each energized phase, that is, the energization pattern of the detection voltage.

  The energization pattern provided in the voltage application phase switching means 6b is set, for example, from energization pattern 0 to energization pattern 5, as shown in FIG. The detection voltage is applied to the armature windings of the energized phases in the order of 1 → 2 → 3 → 4 → 5. The detection voltage may be applied in any order regardless of the order of the energization patterns. In short, the detection voltage is not the order of the energization patterns, and the detection voltage is applied to the armature of each energization phase. It is set to apply to the winding without omission.

  Next, the rotor magnetic pole position estimating means 7 compares the armature current flowing through the armature winding of each phase energized phase detected by the current detection circuit 5 for each armature winding, and the maximum armature current is obtained. A function for selecting an energized phase of the flowing armature winding, a function for estimating the selected energized phase as a rotor magnetic pole position, and a signal (command) indicating that the rotor magnetic pole position is an estimated energized phase. And a function of outputting to a rotor starting unit 8 to be described later.

  Then, in the armature current that flows when a detection voltage is applied (energized) to the armature winding of each energized phase, the rotor 2a and the magnetic pole of a stator core (not shown) around which the armature winding is wound If the positional relationship is such that the magnetic flux easily flows, that is, if the magnetic pole of the stator core is, for example, N pole and the rotor 2a side corresponding to this N pole is the S pole, the magnetic flux flows from the stator core side to the rotor 2a. The magnetic pole [N pole] of the stator core and the [S pole] on the rotor 2a side are opposed to each other and attract each other. Therefore, the armature current flows best in the armature winding wound around the portion where the magnetic poles of the stator core exist by applying the detection voltage.

  As a result, the armature current flowing in the armature winding is such that the magnetic pole of the stator core around which the other armature winding is wound is, for example, N poles on the rotor 2a side facing this N pole. In this case, since the magnetic fluxes hardly repel each other, only a small current flows through the armature winding, and a large armature current flows compared to the armature winding in this case. Become.

  In this way, by applying the detection voltage to the armature winding of each energized phase, the armature winding of each energized phase has a case where the magnetic flux flows well and a case where it is difficult to flow, Differences occur in the armature currents flowing through the armature windings, and the armature currents flowing through these armature windings are sequentially detected by the current detection circuit 5 and output to the rotor magnetic pole position estimating means 7. As described above, the rotor magnetic pole position estimating means 7 grasps the magnitude of the armature current flowing through the armature winding of each energized phase and determines the position of the rotor magnetic pole so that the maximum armature current flows. It is presumed that this is the magnetic pole of the stator core around which the winding is wound. As described above, this is because the magnetic poles of the stator core and the rotor 2a are present at positions where the magnetic flux flows most easily.

  Subsequently, the rotor starting unit 8 includes a starting voltage energizing phase setting unit 8a and a starting voltage energizing unit 8b. The starting voltage energizing phase setting unit 8a energizes a starting voltage for starting the rotor 2a. When the energized phase for energizing the starting voltage is set, the energized phase positioned next to the energized phase with respect to the energized phase set by the rotor magnetic pole position estimating means 7 is provided. Is configured to have a function of setting the energization phase to energize the starting voltage.

  When setting the energized phase for energizing the starting voltage, for example, when the rotor 2a is rotated in the right direction (clockwise) in FIG. 2, the rotor magnetic pole position estimation means 7 estimates the rotor magnetic pole position. The energized phase of the next phase located on the right side (clockwise side) of the energized phase as a base point is set as the energized phase for energizing the starting voltage first, and conversely in the left direction (counterclockwise direction) in FIG. When rotating, the energized phase of the next phase located on the left side (counterclockwise side) of the energized phase estimated as the rotor magnetic pole position is set as the energized phase for energizing the starting voltage first. Yes. This is because the S pole of the rotor is attracted to the N pole on the magnetic pole side of the stator core. This is because the S pole of the rotor 2a has two relative positions at which it attracts well to the N pole of the magnetic pole of the stator core around which the armature winding of the energized phase estimated as the rotor magnetic pole position is wound. The energized phase present in the next phase of the energized phase that is estimated to be the rotor magnetic pole position is the magnetic pole (N pole) of the stator core around which the armature winding of the energized phase (next phase) is wound. On the other hand, the S pole of the rotor 2a has less attractive force than the stator core around which the armature winding of the energized phase estimated as the rotor magnetic pole position is wound, but the magnetic flux is the rotor 2a and the stator. Since it is the second most easily flowing portion between the core and the energized phase of the next phase, the rotor 2a is smoothly and satisfactorily activated to the energized phase side that has been energized. be able to.

  At this time, it is conceivable to apply a starting voltage to the energized phase estimated as the rotor magnetic pole position. In this energized phase, although the magnetic flux flows best when the detection voltage is applied, the starting voltage is applied to the armature winding. Since the rotor 2a is in a good attractive relationship with the stator core even when the current is applied, the rotor is not immediately rotated by the energization of the starting voltage, but only attracts. For this reason, for example, the rotor start position of the rotor is set using a rotor position detection sensor such as a Hall IC in order to immediately rotate in the set rotation direction, and energization is performed in the rotation direction of the rotor. We responded by doing.

  However, in the present invention, as described above, in order to start the rotor 2a without using a rotor position detection sensor such as a Hall IC, the rotor magnetic pole position and the energized phase estimated as the base point are used. The rotor 2a can be smoothly started by supplying a voltage that can rotate the rotor 2a to the energized phase of the next phase that is positioned at. And about the voltage which rotates the said rotor 2a, the voltage set by the starting voltage electricity supply means 8b which comprises one side of the rotor starting part 8 is sequentially set for the time set to the armature winding of the predetermined energization phase. It is configured to energize. The energization time of each start-up voltage to each energized phase is, for example, 70% of the first energization time for the energization of the next phase, and the third energization for the energization time of the first energization phase (100%). The energization time to the phase is configured so that the energization can be performed by sequentially reducing the energization time to 70% of the energization time of the previous phase.

  Next, the sensorless driving unit 9 will be described. The sensorless drive unit 9 includes a sensorless drive switching unit 9a and a commutation command unit 9b. The sensorless drive switching unit 9a sets in advance the rotation speed of the rotor 2a activated by the rotor activation unit 8. And a function for determining whether or not the rotation speed of the rotor 2a has reached a predetermined rotation speed, and a function for switching the activation of the rotor 2a to sensorless drive. Has been. Further, the commutation command means 9b indicates that the armature current flowing through the armature winding in the energized phase when the activation of the rotor 2a is switched to the sensorless drive by the sensorless drive switching means 9a is ½ hour of the energization time. And confirming that it has reached a predetermined multiple (for example, 1.3 times) of the detected armature current, and having the function of switching the energized phase by outputting a commutation command by this confirmation Yes.

  The sensorless drive unit 9 detects the current value detected after the rotor 2a of the PM brushless motor 2 has reached a predetermined number of rotations after startup, and the armature current flowing through the armature winding has passed half the energization time. Commutation command is output when 1.3 times or more. For example, as shown in FIG. 6, a commutation command is output when the second current increase region b reaches 1.3 times or more than the first current increase region a. Therefore, the PM brushless motor 2 can be smoothly driven without using the rotor magnetic pole position sensor by switching to sensorless driving.

  In FIG. 1, the three-phase inverter control means 10 includes a starting position detector 6, each of the transistors U, V, W, x, y, and z that constitute the upper arm portion 4 a and the lower arm portion 4 b that constitute the inverter circuit 4. Based on commands output from the rotor starting unit 8 and the sensorless driving unit 9, a function for ON / OFF control of the required time, and a predetermined energization pattern and commutation for each transistor U, V, W, x, y, z Each time a command is output, it has a function of performing ON / OFF control in order to switch the energization to a required energization phase.

  Further, in FIG. 1, when the drive of the PM brushless motor 2 is stopped by a switch (not shown), the sensorless drive stopping unit 11 is a current flowing through the armature winding of each energized phase detected by the current detection circuit 5. Is lowered to a predetermined current value, the rotor soft stop means 11a causes the three-phase inverter control means 10 to turn on the lower arm 4b of the inverter circuit 4 every predetermined time so that the armature windings of each phase are short-circuited. By doing so, the rotor 2a is reduced for a while and then stopped in a software manner.

  Next, the operation of the drive control device 1 for the PM brushless motor 2 configured as described above will be described. When an AC voltage of the commercial power supply 100V is supplied from the AC power supply 20 to the AC / DC conversion circuit 3, the AC / DC conversion circuit 3 stabilizes, for example, 5V to each part / means of the drive control device 1. A constant voltage power supply Vcc is supplied via the constant voltage power supply circuit 12. At this time, the PM brushless motor 2 is supplied from the AC / DC conversion circuit 3 through the inverter circuit 4 to the PM brushless motor 2 in response to a command from the drive control device 1 (AC power supply, for example, 100V). ) Is not supplied.

  Next, a case where the PM brushless motor 2 is started will be described. When starting the PM brushless motor 2, the PM brushless motor 2 needs to estimate the rotation start position of the rotor 2a, that is, the rotor magnetic pole position, in order to perform sensorless driving. In the present invention, first, the armature current flowing in the armature winding of each energized phase (U, V, W) wound around the stator core (not shown) of the PM brushless motor 2 is detected to detect the armature current of the rotor 2a. The rotor magnetic pole position is estimated.

  When detecting the armature current flowing through the armature winding of each energized phase, a voltage for detecting is applied to the armature winding of each energized phase for a predetermined time by the voltage applying means 6a provided in the starting position detector 6. To detect. As the voltage for detecting the rotor magnetic pole position, an AC voltage (12V) that does not rotate the rotor 2a in this example is output from a predetermined output terminal of the inverter circuit 4 for 0.01 seconds to obtain a PM brushless motor. 2 is applied to the energized phase connected to the output terminal of the inverter circuit 4.

  In the application of the AC voltage, the voltage application phase switching means 6b converts the DC voltage of 12V from the AC / DC conversion circuit 3 to the AC by the inverter circuit 4 in accordance with the energization pattern as shown in FIG. Applied to the armature winding of each energized phase. In FIG. 2, when applying the detection voltage to the armature winding of each energized phase, the detection voltage is sequentially applied according to the sequence 0 to 5 of the energization patterns shown in FIG. That is, the energization pattern 0 indicates a pattern in which the detection voltage is first applied to the U-phase (energized phase) armature winding. In this case, the inverter circuit 4 is controlled by a command from the voltage application phase switching means 6b. The transistor U of the upper arm 4a and the transistor y of the lower arm 4b are turned on and the voltage is applied for 0.01 second.

  When the application of the voltage by the energization pattern 0 is completed, the energization pattern 1 is turned off simultaneously with turning off the transistors U and y of the inverter circuit 4 that has been turned on in the energization pattern 0 by the command from the voltage application phase switching means 6b. Thus, the transistors U and z of the inverter circuit 4 are turned ON, and the second detection voltage is applied to the U-phase armature winding. Similarly, in the energization pattern 2, the transistors U and z of the inverter circuit 4 in the energization pattern 1 are turned off, the transistors V and z are turned on, and the first detection voltage is applied to the V-phase armature winding. To do.

  In the energization pattern 3, the transistors V and z of the inverter circuit 4 are turned off and V and x are turned on, and the second voltage is applied to the V-phase armature winding. In the energization pattern 4, the transistors V and x of the inverter circuit 4 are turned off and W and x are turned on to apply the first detection voltage to the W-phase armature winding. The transistors W and x are turned off, W and y are turned on, and the second detection voltage is applied to the W-phase armature winding. In this manner, the detection voltage is sequentially applied to the predetermined armature windings according to the predetermined energization pattern to the armature windings in the energized phase.

  As described above, when the detection voltage is applied to the armature winding of each energized phase by the starting position detection unit 6, an armature current flows through each armature winding. This armature current is detected by the shunt resistance of the current detection circuit 5 for each energized winding of each energized phase, converted into a voltage, and output to the rotor magnetic pole position estimating means 7 (see FIG. 3A). .

  When the armature current flowing through the armature winding of each energized phase output from the current detection circuit 5 is input to the rotor magnetic pole position estimating means 7, the rotor magnetic pole position estimating means 7 The armature current flowing through the armature winding of the energized phase is compared for each energized phase, and the energized phase through which the maximum armature current flows is selected. In the case of this example, as shown in the current waveform diagram of FIG. 3A, the armature current that flows when the second detection voltage is applied to the W-phase armature winding by the energization pattern 5 is the maximum. (See (f) in FIG. 3A).

  As shown in FIGS. 2, 3B and 3C, the S pole of the rotor 2a is collinear with the magnetic pole N of the stator core around which the W-phase armature winding is wound. This is nothing but the correspondence (see FIG. 2). That is, since the S pole of the rotor 2a corresponds to the N pole of the stator core in a normal state, the magnetic flux generated when a voltage is applied to the W-phase armature winding is detected the second time. A large amount of armature current flows by flowing smoothly without receiving any resistance between the stator iron core wound with the W-phase armature winding to which a voltage is applied and the rotor 2a. It will be. In this case, as shown in (f) of FIG. 3B, the rotor 2a holds the stopped state without rotating. This is because the south pole of the rotor 2a and the north pole generated in the magnetic pole of the stator core attract each other in a well-balanced manner.

  Incidentally, when the first detection voltage is applied to the V-phase armature winding by the energization pattern 2 shown in FIG. 2, the N pole of the rotor 2a and the N pole generated at the magnetic pole of the stator core are generated. Because of the repulsive state corresponding to each other, even when a detection voltage is applied to the V-phase armature winding, as shown by the current waveform shown in FIG. In the V-phase armature winding in FIG. This is because the N pole on the rotor 2a side and the N pole on the magnetic pole side of the stator core repel each other and it is difficult for the magnetic flux to flow (see (c) in FIG. 3B).

  In addition to the energization patterns 5 and 2, in the case of the energization pattern 0, the magnetic pole side of the stator iron core wound with the armature winding to which the detection voltage is applied for the first time of the S pole and the U phase of the rotor 2a As shown in FIG. 3 (b) (A), the N pole of N is moving (attracting) in the clockwise direction (right side). On the other hand, in the energization pattern 4, on the N pole side of the magnetic pole of the stator core wound with the armature winding to which the detection voltage is applied for the first time in the W phase, As shown, the rotor 2a is about to move (counterclockwise (left side)) with the south pole attracted.

  Further, in the energization patterns 1 and 3 shown in FIG. 2, when the detection voltage is applied to the U-phase and V-phase armature windings for the second time, (b) and (d) of FIG. As shown in FIG. 4, the N pole on the rotor 2a side repels the N pole on the magnetic pole side of the stator core around which the U and V phase armature windings are wound. In FIG. 3B, the rotor 2a is clockwise (right side), and in the energization pattern 3, the rotor 2a is counterclockwise (as shown in FIG. Trying to move to the left).

  As described above, when a detection voltage is applied to the armature winding of each phase, the magnetic flux easily flows between the S pole of the rotor 2a and the magnetic pole (N pole) of the stator core around which the armature winding is wound. The energization amount (large / small) of the armature current flowing through each armature winding is determined depending on whether or not the position corresponds, and the energization amount depends on the current waveform shown in FIG. It can be seen at a glance whether the energization pattern is most likely to cause the current to flow, and in this example, it is the armature winding to which the detection voltage is applied for the second time of the W phase shown in the energization pattern 5, as described above, This is because the relationship between the rotor 2a and the magnetic poles of the stator core is maintained in the best condition. In this case, the S pole of the rotor 2a is located at a position other than the energization pattern 5 in FIG. Even when it is stopped at the same time, the same effect as the energization pattern 5 is obtained. It is needless to say to say.

  When the energized phase through which the maximum armature current flows in the armature winding is selected, the rotor magnetic pole position estimating means 7 detects the voltage for the second detection of the energized phase, in this example, the W phase selected by the energization pattern 5. The magnetic pole of the stator core around which the armature winding to which the coil is applied is estimated as the rotor magnetic pole position, and the armature winding wound around the stator core around the starting voltage conduction phase setting means 8a of the rotor starting unit 8 Information that the energized phase having the line is estimated to be the rotor magnetic pole position is output (see (f) in FIG. 3C).

  When the information that estimates the rotor magnetic pole position is output to the starting voltage energized phase setting means 8a, the starting voltage energized phase setting means 8a determines the energization of the starting voltage for starting the rotor 2a as the next phase of the estimated energized phase. When the rotor 2a is rotated in the right direction in FIG. 2 when the rotor 2a is rotated to the right in FIG. If the rotation direction of the rotor 2a is to the left, the armature winding to which the W-phase first detection voltage shown in the energization pattern 4 is applied is the energized phase. Are set and output to the three-phase inverter control means 10. The energization phase is set such that the S pole of the rotor 2a is attracted to the magnetic pole (N pole) side of the stator core in the energization patterns (A) and (E) shown in FIG. Therefore, the energized phase next to the energized phase estimated as the rotor magnetic pole position is set as the energized phase of the starting voltage.

  The three-phase inverter control means 10 corresponds to the output from the starting voltage energization phase setting means 8a. When the output rotates, for example, the rotor 2a in the right direction, the U-phase shown in the energization pattern 0 shown in FIG. In order to set the armature winding to which the detection voltage is applied at the beginning of the phase as the energized phase in which the starting voltage is first supplied, the transistors U and y of the inverter circuit 4 are turned on, and the starting voltage is set to the U-phase armature Energize the windings. When the rotation direction of the rotor 2a is the left direction, as described above, the W-phase armature winding of the energization pattern 4 (the armature winding to which the detection voltage is first applied) is first activated. Is set as the energized phase.

  When the energization phase for energizing the start-up voltage is set as described above, the start-up voltage energization means 8b is activated and energizes the start-up voltage (for example, AC voltage 5V) from the output terminal of the inverter circuit 4 to the U-phase armature winding. Then, the rotor 2a is activated (rotated).

  When energizing the starting voltage, 5 V is applied to the first energized phase (U1 shown in the energization pattern 0 shown in FIG. 2, that is, the armature winding (U1) to which the detection voltage is applied in the first phase of the U phase). Next, to the next energized phase (U2 of the energization pattern 1 shown in FIG. 2, that is, the armature winding to which the detection voltage is applied for the second time of the U phase). In the energization, the energization time is set to 70% with respect to the first energization time in the next energization phase at an interval of 0.02 seconds after completion of energization of the first energized starting voltage. The energization phase (V1 of the energization pattern 2 shown in FIG. 2, that is, the armature winding to which the detection voltage is applied for the first time of the V phase) is energized as 70% of the second energization time (FIG. 4). FIG. 5).

  Thus, when energizing the starting voltage, when the energizing phase for energizing the starting voltage is set, the energization shown in FIG. 2 is used when the rotor 2a is rotated clockwise with the set energizing phase as a base point. The rotor 2a is energized by sequentially reducing the energization time of the starting voltage by 30% sequentially to the armature windings U1 → U2 → V1... Of the corresponding energized phase in the order of moving the pattern in the clockwise direction. Start (rotate). When rotating the rotor 2a counterclockwise, the energization time of the starting voltage is reduced by 30% for a while in the order of the armature windings W1 → V2 → V1. The rotor 2a is activated (rotated) in the left direction. As shown in FIG. 2, the energization phase in which the starting voltage is energized has the S pole of the rotor 2a located at the position of the energization pattern 0. Therefore, the energization phase may be energized or the S pole of the rotor 2a. However, if, for example, it is at the position of the energization pattern 0, the energized phase U1 at that position (the armature winding that energizes the detection voltage for the first time of the U phase) is estimated as the rotor magnetic pole position. When the rotor 2a rotates in the right direction, the voltage is applied to the energization phase (U2) of the energization pattern 1, and to the left direction, the energization phase (W1) of the energization pattern 5 is energized.

  Then, as described above, when the rotor 2a is activated and its rotational speed reaches a predetermined rotational speed (for example, 500 times / minute), the activation of the rotor is switched to sensorless driving. In this case, the number of rotations that can be achieved by energizing the starting voltage to the first energized phase and then energizing the third to fifth times, that is, by energizing the starting voltage to the energized phases shown in the energization patterns 3 to 5. In addition, the energization time is sequentially reduced because if the rotor 2a starts to start, the energization time can be reduced smoothly without decreasing even if the energization time is reduced unless the rotational torque changes abruptly. Because it can. If the rotational speed of the rotor 2a does not reach the set rotational speed even when the starting voltage is applied, the rotor 2a is determined to be abnormal and the starting of the rotor 2a is stopped. The rotor magnetic pole position is detected and the PM brushless motor 2 is activated.

  As described above, the start-up voltage is sequentially applied to the armature windings of a predetermined energized phase, and when the rotor 2a reaches a predetermined number of rotations, the start-up of the rotor 2a is switched to immediate sensorless drive. Whether or not the rotational speed of the rotor 2a has reached a predetermined rotational speed is determined by whether the armature current flowing through the armature winding of the energized phase energized with the starting voltage detected by the current detection circuit 5 is rotated. When the sensorless drive switching unit 9a of the sensorless drive unit 9 detects a current that flows when the rotation speed of the child 2a reaches 500 times / minute, the sensorless drive switching unit 9a detects an energized voltage suitable for sensorless drive (for example, AC voltage 100V) is set and output to the three-phase inverter control means 10, and the inverter circuit 4 is ON / OFF controlled so as to energize the PM brushless motor 2 with a voltage suitable for sensorless driving, and is always suitable for sensorless driving. Can supply.

  When the rotation of the rotor 2a is switched to the sensorless drive by the sensorless drive switching means 9a, the armature current flowing in the armature winding of the energized phase is, for example, as shown in the current waveform diagram of FIG. When the current detected by the current detection circuit 5 has reached 1.3 times or more after ½ hour of the energization time in the phase, the commutation command means 9b of the sensorless drive unit 9 is activated and commutated. A command is output to the three-phase inverter control means 10, and a required transistor of the inverter circuit 4 is ON / 0FF controlled to sequentially switch the energized phase, thereby continuing the sensorless drive.

  In this case, when the rotational speed of the rotor 2a does not change specially in relation to the load, the commutation cycle is shortened for a while as shown in the current waveform diagram of FIG. 6, and conversely, the rotational torque of the rotor 2a Is increased in relation to the load, the commutation cycle becomes longer, and the rotation speed of the rotor 2a is always kept constant by automatically adjusting the commutation cycle according to the torque of the load. ing.

  As described above, in the present invention, when starting the rotor 2a, the detection voltage is applied to the armature winding of each energized phase according to a predetermined energization pattern (see FIG. 2), and the armature current in each energized phase is applied. By detecting, the energized phase that becomes the rotor magnetic pole position is estimated, and when the rotor 2a is activated by energizing the required energized phase with the start voltage, it exists before and after the estimated energized phase as the rotor magnetic pole position. An energized phase existing at a position suitable for the rotation direction of the rotor 2a is set from the energized phase to be started, and the rotor 2a is activated by energizing the energized phase with a starting voltage (see S1 to S4 in FIG. 7).

  When the rotor 2a is activated and the rotational speed reaches the set rotational speed, the rotor 2a can automatically shift to sensorless driving and perform sensorless driving. Therefore, the PM brushless motor 2 is It is possible to rotate quickly and accurately, smoothly and satisfactorily from the start to the sensorless drive, eliminating any problem of the rotor 2a swinging at the start-up or unstable rotation direction. Thus, it is possible to always perform sensorless driving smoothly without inducing step-out or the like due to insufficient rotation speed at startup. When the sensorless drive cannot be switched to the sensorless drive, the rotation of the rotor 2a is stopped, and if there is no problem in investigating the cause of the switching, the rotor 2a is started again from the beginning to execute the sensorless drive. (See S5 to S9 in FIG. 7).

  Next, the case where the PM brushless motor 2 is stopped will be described. In this case, after the PM brushless motor 2 is operated by a switch (not shown) to stop energization of each energized phase, the rotor soft stops when the current detected by the current detection circuit 5 drops to a predetermined current value. The means 11a is actuated, and the lower arm 4b of the inverter circuit 4 is turned on for a predetermined time (for example, 0.5 seconds) by the three-phase inverter control device 10 to short-circuit. By adopting this rotor soft stop means 11a, it is possible to decelerate a device such as an electric pump or an electric compressor in a short time without being influenced by the load (see S10 to S11 in FIG. 7).

It is a block diagram which shows roughly the drive control apparatus of the brushless sensorless DC motor which is an Example of this invention. It is explanatory drawing which shows the process of the electricity supply pattern for estimating the rotor magnetic pole position at the time of starting of the brushless sensorless DC motor of this invention. (A) is a wave form diagram which shows the armature electric current which flows into each armature winding, when the voltage for rotor magnetic pole position detection is applied to the armature winding of each energized phase. (B) is explanatory drawing which shows in which direction a rotor is going to rotate with the electric current which flows into an armature winding, when the voltage for rotor magnetic pole position detection is applied to the armature winding of each energized phase. . (C) is a timing chart showing a state in which a rotor magnetic pole position detection voltage is applied to each armature winding in accordance with an energization pattern. It is a timing chart figure which shows the condition which energizes starting voltage according to a predetermined energization pattern at the time of starting of a rotor. It is a current waveform diagram explaining the energization situation at the time of starting of the brushless sensorless DC motor of the present invention. It is a current waveform diagram explaining the energization situation at the time of sensorless drive of the brushless sensorless DC motor of the present invention. It is a flowchart explaining the process until the brushless sensorless DC motor of the present invention is driven sensorlessly.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drive control apparatus 2 PM brushless motor 2a Rotor 3 AC / DC conversion circuit 4 Inverter circuit 5 Current detection circuit 6 Starting position detection part 6a Voltage application means 6b Voltage application phase switching means 7 Rotor magnetic pole position estimation means 8 Rotor activation Section 8a Start voltage energization phase setting means 8b Start voltage energization means 9 Sensorless drive section 9a Sensorless drive switching means 9b Commutation command means 10 Three-phase inverter control means 11 Sensorless drive stop section 11a Rotor software stop means 12 Constant voltage power supply circuit

Claims (10)

  An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Apply sequentially for a predetermined time, and apply each of the energized phases based on the magnetic flux flowing between the magnetic pole and the rotor of the stator core wound with the armature winding of each energized phase by applying the voltage for detecting the rotor magnetic pole position. The armature current flowing through the armature winding is detected for each energized phase to select the energized phase of the armature winding through which the maximum current flows, and the selected energized phase is rotated. The rotor magnetic pole position is estimated, and the rotor is started by supplying a required starting voltage to the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position. A brushless / sensorless DC motor drive method.   An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Apply sequentially for a predetermined time, and apply each of the energized phases based on the magnetic flux flowing between the magnetic pole and the rotor of the stator core wound with the armature winding of each energized phase by applying the voltage for detecting the rotor magnetic pole position. The armature current flowing through the armature winding is detected for each energized phase to select the energized phase of the armature winding through which the maximum current flows, and the selected energized phase is rotated. Predetermined starting voltage set in advance in the armature winding of each energized phase according to a predetermined energization pattern from the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position A method of driving a brushless sensorless DC motor, wherein the rotor is driven by energizing the power supply for a predetermined energizing time and then energizing the energizing time for a while for each energized phase.   An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Apply sequentially for a predetermined time, and apply each of the energized phases based on the magnetic flux flowing between the magnetic pole and the rotor of the stator core wound with the armature winding of each energized phase by applying the voltage for detecting the rotor magnetic pole position. The armature current flowing through the armature winding is detected for each energized phase to select the energized phase of the armature winding through which the maximum current flows, and the selected energized phase is rotated. Predetermined starting voltage set in advance in the armature winding of each energized phase according to a predetermined energization pattern from the armature winding of the next phase of the energized phase estimated as the rotor magnetic pole position After energizing for a predetermined energizing time, the energizing time is decreased for each energizing phase for a while to energize to start the rotor, and further, the rotation speed is set to a preset rotation speed by starting the rotor. When the rotation speed has reached the set rotation speed by determining whether or not the armature has reached, the armature detected by the armature current flowing through the armature winding of the current-carrying phase after the lapse of 1/2 hour of the current-carrying time A brushless, characterized by outputting a commutation command when the current has reached a predetermined multiple and switching the energized phase to switch the start of the rotor to sensorless drive and drive the rotor. Driving method of sensorless DC motor   An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Sequentially applied rotor starting position detector, current detection circuit for detecting the armature current flowing in the armature winding of each energized phase for each energized phase, and the armature winding of each energized phase The armature winding of each energized phase is based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position. The armature current flowing in the armature is detected by the current detection circuit, the magnitude of the armature current is compared for each armature winding of each energized phase, and the energized phase of the armature winding through which the maximum current flows is selected. The rotor magnetic pole position estimating means for estimating the energized phase as the rotor magnetic pole position and the armature winding located in the next phase of the energized phase estimated as the rotor magnetic pole position are energized with a predetermined starting voltage to rotate. A drive control device for a brushless / sensorless DC motor, characterized by comprising a rotor starting section for starting a child.   An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Sequentially applied rotor starting position detector, current detection circuit for detecting the armature current flowing in the armature winding of each energized phase for each energized phase, and the armature winding of each energized phase The armature winding of each energized phase is based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position. The armature current flowing in the armature is detected by the current detection circuit, the magnitude of the armature current is compared for each armature winding of each energized phase, and the energized phase of the armature winding through which the maximum current flows is selected. Rotor magnetic pole position estimating means for estimating the energized phase as the rotor magnetic pole position, and estimating the selected energized phase as the rotor magnetic pole position, and the electrical machine of the next phase of the energized phase estimated as the rotor magnetic pole position. After energizing the armature winding of each energized phase in advance to the armature winding of each energized phase sequentially for a predetermined energizing time in accordance with a predetermined energization pattern from the child winding, the energizing time is decreased for each energized phase for a while to energize A drive control device for a brushless and sensorless DC motor, characterized by comprising a rotor starting unit that performs the above.   An inverter circuit that supplies an alternating voltage to the armature winding of each energized phase of the brushless sensorless DC motor, and a drive control circuit that causes the inverter circuit to perform commutation and rotate the brushless sensorless DC motor. In the brushless / sensorless DC motor drive control system configured as described above, the rotor magnetic pole position detection voltage is such that the rotor having a permanent magnet around the armature winding of each energized phase according to a predetermined energization pattern does not rotate. Sequentially applied rotor starting position detector, current detection circuit for detecting the armature current flowing in the armature winding of each energized phase for each energized phase, and the armature winding of each energized phase The armature winding of each energized phase is based on the magnetic flux flowing between the magnetic pole of the stator core and the rotor wound with the armature winding by the voltage for detecting the rotor magnetic pole position. The armature current flowing in the armature is detected by the current detection circuit, the magnitude of the armature current is compared for each armature winding of each energized phase, and the energized phase of the armature winding through which the maximum current flows is selected. Rotor magnetic pole position estimating means for estimating the energized phase as the rotor magnetic pole position, and estimating the selected energized phase as the rotor magnetic pole position, and the electrical machine of the next phase of the energized phase estimated as the rotor magnetic pole position. After energizing the armature winding of each energized phase in advance to the armature winding of each energized phase sequentially for a predetermined energizing time in accordance with a predetermined energization pattern from the child winding, the energizing time is decreased for each energized phase for a while to energize A rotor starter that performs the determination, and further, whether or not the rotational speed has reached a predetermined set rotational speed by starting the rotor, and if the rotational speed has reached the set rotational speed, The armature current flowing through the armature winding is 1 / Brushless and sensorless, comprising a sensorless drive unit that outputs a commutation command and switches the energized phase to drive the rotor in a sensorless manner when the armature current detected after a lapse of time is reached. DC motor drive control device.   The starting position detecting unit includes a starting position detecting voltage applying means for applying a voltage at which the rotor does not rotate to the armature winding of each energized phase, and the starting position detecting voltage according to a predetermined energizing pattern. 7. The brushless / sensorless DC motor drive control device according to claim 4, further comprising voltage application phase switching means for sequentially applying to the armature winding of the energized phase.   The rotor magnetic pole position estimating means compares the armature current flowing through the armature winding of each energized phase detected by the current detection circuit and selects the energized phase through which the maximum armature current flows, and the selection 7. The drive control device for a brushless / sensorless DC motor according to claim 4, 5 or 6, further comprising a function of estimating the energized phase as a rotor magnetic pole position.   The rotor starting unit is a starting voltage for setting a current-carrying phase positioned next to a current-carrying phase of the rotor magnetic pole position estimated by the rotor magnetic pole position estimating means as a current-carrying phase that first supplies a starting voltage. 7. A brushless sensorless DC motor according to claim 4, further comprising: an energized phase setting means; and a starting voltage energizing means for energizing a predetermined starting voltage to the set energized phase. Drive control device.   The sensorless drive unit determines whether or not the rotational speed has reached a preset rotational speed by starting the rotor, and switches the rotor start to sensorless driving if the rotational speed has reached a predetermined rotational speed. When the armature current flowing in the armature winding of the energized phase when switching to the sensorless drive switching means and the sensorless drive has reached a predetermined multiple of the armature current detected after ½ hour of the energization time has elapsed 7. A drive control apparatus for a brushless sensorless DC motor according to claim 6, further comprising a commutation command means for outputting a commutation command to switch the energized phase.

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