JP2006223013A - Controller for brushless dc motor and conveyance apparatus therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To exactly keep rotational speed constant in a conveyance apparatus installed with rollers driven by a controller for a brushless DC motor. <P>SOLUTION: This controller includes a rotational speed feedback device 6 for comparing a predetermined target rotational speed with a rotational speed detected by a rotational speed detector 3, for outputting a signal for changing a DC power supply 108 applied to a stator winding 103 according to a difference between the rotational speeds to a DC voltage changer 109, and for controlling the rotational speed so as to meet the target rotational speed. With this arrangement, a time interval of one-turn duration is measured with a mechanical angle of a brushless DC motor 102, and a rotational speed is detected based on an average of the time intervals of one-turn duration, thus exactly providing the rotational speed. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a brushless DC motor control device in which the number of rotations is made exactly constant and the controllability and stability at the time of start and stop are improved, and a transport device equipped with the same.

  In recent years, highly efficient AC servo motors and brushless DC motors have been adopted from the viewpoint of energy saving and controllability. In addition, although it is expensive, the position detection accuracy and rotation speed accuracy are increased or increased using an encoder, but the torque is increased and the controllability is increased. A brushless DC motor that uses a detection element to reduce the cost by reducing the resolution of position detection and the resolution of the number of revolutions, or reducing the torque and reducing the size is adopted. The brushless DC motor control device has a resolution of position detection. It is desirable to improve position detection accuracy and rotation speed accuracy, and to widen the rotation speed adjustment range to achieve stable and constant rotation from low speed to high speed. At the same time, stability over a wide rotational speed range is desired.

  It is desirable to reach the target rotational speed at the fastest speed when starting and stopping, and to reach the target rotational speed stably over a certain period of time. Controllability and stability when starting and stopping It is required to increase.

  Brushless DC motors are used to drive the rollers in order to reduce the size and cost of the rollers in order to drive the rollers in the transport device that drives the rollers. The range of rotation of the rollers can be adjusted to increase the accuracy of the rotation speed of each roller so that it does not collide with the adjacent baggage, and to cope with high-mix low-volume production and frequent layout changes in the factory. It is desired that the rollers rotate stably over the entire range from low speed to high speed, and the accuracy of the rotational speed during normal conveyance is increased and stability in a wide rotational speed range is required. .

  Also, when starting or stopping transportation, the roller rotates and the load reaches the target speed at the fastest speed, or conversely, the target rotation is gradually accelerated over a certain period of time so that the load does not fall down. It is desired to stably reach the number, and it is required to improve the controllability and stability when starting or stopping the conveyance.

  Conventionally, an example of this type of roller and conveying device has a structure as shown in FIGS. As shown in FIG. 32, a brushless DC motor 102 is built in the roller 113. The brushless DC motor 102 includes a stator winding 103 (not shown) and position detection elements 2a, 2b, 2c (not shown). It is built in and connected to a DC motor control device 101 (not shown) installed outside the roller 113 and built in the circuit box 104. Further, as shown in FIG. 33, a roller 113a incorporating a brushless DC motor 102 is mechanically connected by a belt 114 to a roller 113b not incorporating the brushless DC motor 102. For example, a roller 113a incorporating the brushless DC motor 102 is replaced by a roller 113a. Two rollers 113b that are not built in one are installed on the frame 115 at a ratio of two, and when the roller 113a rotates, the other two rollers 113b also rotate, and a large number of these rollers are arranged to form a conveying device. . The baggage 105 is conveyed on the roller of this conveying apparatus. The DC motor control device 101 built in each circuit box 104 is connected to a DC power supply 108 and receives external DC power supply and inputs external signals (not shown) such as operation, stop and speed control commands. .

  As a control method for keeping the rotation speed of the brushless DC motor 102 constant, those shown in FIGS. 34 and 35 are known. The control method will be described below with reference to FIG. From FIG. 34, the rotor 106 is provided with N-pole and S-pole magnets alternately, and three position detections mounted on the electric circuit board 1 fixed to the stator in order to detect the position of the rotor 106. The hall sensors 2a, 2b, and 2c, which are elements, transmit the electrical signals of H and L when the magnet of the rotor 106 changes from the north pole to the south pole and from the south pole to the north pole as position detection signals to the microcomputer 107. You are typing. The microcomputer 107 inputs a position detection signal to the rotation speed detection means 3, counts position detection signals generated from a plurality of position detection elements, and detects the rotation speed based on the count number for a predetermined time.

  The rotational speed feedback means 6 compares a predetermined target rotational speed with the rotational speed output from the rotational speed detection means 3, and outputs a signal for changing the voltage of the DC power supply 108 applied to the stator according to the rotational speed difference. The output is controlled so that the rotational speed matches the target rotational speed.

  The DC voltage changing means 109 performs PWM modulation based on a signal for changing the DC voltage applied to the stator winding output from the rotation speed feedback means 6 and outputs the result to the drive signal generating means 110.

  The drive signal generating means 110 captures changes in the position detection signals of the three position detection elements, and sequentially applies the U, V, and W of the stator winding 103 in a predetermined direction and order according to the state of the position detection signals at that time. A signal for changing the DC voltage applied to the U, V, and W of the stator windings based on the PWM modulated signal output from the DC voltage changing means 109 is supplied to the drive means 111 while being energized.

  The rotation speed detection means 3, the rotation speed feedback means 6, the DC voltage change means 109, and the drive signal generation means 110 are built in the microcomputer 107.

  The drive means 111 converts the switching element of the switching means 112 into a signal for turning on and off based on the signal output from the drive signal generating means 110 built in the microcomputer 107.

  The switching means 112 is connected to the DC power source 108 and comprises six switching elements Q1, Q2, Q3, Q4, Q5, Q6 and freewheeling diodes D1, D2, D3, D4, D5, D6. The U, V, and W are sequentially energized at a predetermined timing, the DC voltage of the DC power supply 108 is changed, and the brushless DC motor 102 is rotated in addition to the U, V, and W of the stator winding 103.

  The DC motor control device 101 includes a microcomputer 107, a drive unit 111, and a switching unit 112. The DC motor 108 receives a DC power supply 108, inputs position detection signals from the hall sensors 2a, 2b, and 2c, and rotates the brushless DC motor 102. And the brushless DC motor 102 is rotated by the switching means 112.

  Here, as shown in FIG. 35, the electrical signals and position detection signals of the Hall sensor of the position detection element are converted into the number of rotations by counting, for example, 24 signals for one rotation, for example, for one second. Specifically, for example, the brushless DC motor 102 rotating at 60 r / min counts 24 times per second. Next, when the rotational speed fluctuated to 62 r / min, the count was similarly 24 counts per second, and there was no difference in the count numbers. To provide a difference, the time for counting had to be extended. In particular, when starting, stopping, or when the number of rotations is low, it is necessary to extend the counting time, and thus the accurate number of rotations cannot be detected. Moreover, the time to start and the time to stop cannot be shortened.

  Another control method for keeping the rotation speed of the brushless DC motor 102 constant is shown in FIG. The control method will be described below with reference to FIG. The rotation speed detection means 3 detects the rotation speed by the time interval measurement means 4 that measures the time interval from when one of the plurality of position detection signals changes until the other one changes.

  Here, the electrical signal and the position detection signal of the Hall sensor of the position detection means change one after the other of the plurality of position detection signals in the brushless DC motor 102 rotating at, for example, 600 r / min. The time interval until this is 4.2 msec. However, variations in the mounting position and angle of components during the manufacture of the three Hall sensors mounted on the electric circuit board fixed to the stator, Variation in the time interval of the position detection signal occurs due to variation in magnetization of the N pole and S pole. For example, when the electrical angle is deviated by 5 degrees, the energization interval is 3.82 msec from Equation 1.

  When converted into the number of revolutions, it was 653 r / min from Equation 2, and the exact number of revolutions could not be detected.

  Further, there is an average of variations in position detection signals of a control device for this type of brushless DC motor 102 (see, for example, Patent Document 1).

  On the other hand, when starting with the conventional brushless DC motor 102 or when the target rotational speed is increased due to the rotational speed change and the rotational speed is increasing, the control method for reaching the target rotational speed at the fastest speed is The rotation speed feedback means 6 outputs a voltage change signal for changing the voltage of the DC power supply 108 applied to the stator according to the difference in the rotation speed, and controls so that the rotation speed matches the target rotation speed. If the target rotational speed increases and the rotational speed increases due to a change in the rotational speed, the energization interval changes significantly and approaches the target rotational speed. The target rotational speed can be reached at the fastest speed by adjusting the voltage changing ratio corresponding to the rotational speed difference. However, when operating at a constant rotational speed, as described above, the rotational speed does not become constant due to variations in the time interval of the position detection signal, and may vary or become unstable. The same applies when stopping at the fastest speed or when the target rotational speed is lowered by changing the rotational speed.

Even when there is no variation in the energization interval, it is often the case that the rate of voltage change corresponding to the difference in the number of revolutions of the revolution number feedback means differs between when operating at a constant speed and when starting up at the fastest speed. In some cases, when the rate of voltage change is adjusted so as to start up at the fastest speed, the rotational speed does not become constant but may fluctuate or become unstable. The same was true when stopping at the fastest speed.
JP 2001-231288 A

  In such a conventional brushless DC motor control device, the time interval of the position detection signal varies due to variations in position and angle in component mounting at the time of manufacturing the position detection element, and variations in the magnetization of the rotor. Therefore, there is a problem that it is impossible to detect a proper rotation speed, and it is required to improve the accuracy of the rotation speed.

  The present invention solves such a conventional problem, and can absorb variations in position and angle in component mounting at the time of manufacture of the position detection means and variations in magnetization of the rotor, thereby detecting an accurate rotational speed. It is an object of the present invention to provide a brushless DC motor control device that can increase the accuracy of the rotational speed.

  In addition, such a conventional brushless DC motor control device is often used in a wide range from a low rotation speed to a high rotation speed, and particularly when starting, stopping or when the rotation speed is low. Since it is necessary to extend the time for detecting, there is a problem that an accurate rotational speed cannot be detected.

  Further, even if the rotational speed is kept constant by the rotational speed detection means and the rotational speed feedback means, the rotational speed may become unstable at a specific rotational speed. This is because, after the rotational speed is determined by the rotational speed detection means, the voltage DC voltage of the stator winding is changed by the rotational speed feedback means, so the timing for detecting the rotational speed and the voltage applied to the stator winding are changed. This happens because of a delay in timing. In particular, it is likely to occur at a position where the variation of the position detection signal is large and the rotation speed is low, and the time for detecting the rotation speed becomes long, and as a result, the interval for feeding back the rotation speed becomes long. Therefore, it is required to improve the stability of the rotational speed from a low rotational speed to a high rotational speed.

  The present invention solves such a conventional problem. Usually, the rotational speed is detected for each position detection signal and the rotational speed is fed back. Depending on the specific rotational speed, the number of rotational speed feedback is reduced. It is an object of the present invention to provide a brushless DC motor control device capable of improving the stability of the rotational speed from a low rotational speed to a high rotational speed by arbitrarily changing the timing for detecting the rotational speed and the timing for feeding back the voltage. .

  Also, when starting, stopping, or changing the target rotational speed, the target rotational speed can be reached at the fastest speed, but when operating at a constant rotational speed, the time interval of the position detection signal varies. There is a problem that the rotation speed does not become constant depending on the speed, and it becomes unstable or unstable, and when starting or stopping, it remains the same as before, but when operating at a constant rotation speed, the accuracy of the rotation speed Is required to be high.

  The present invention solves such a conventional problem, and when operating at a constant rotation speed, the rotation speed can be stabilized and the accuracy can be improved, and when starting or stopping, it is the fastest. An object of the present invention is to provide a brushless DC motor control device capable of reaching a target rotational speed.

  In addition, when starting or stopping, the target speed can be reached at the fastest speed, but when the rate of change in the voltage of the speed feedback is adjusted so that it starts and stops at the fastest speed, the speed is constant. When operating, there is a problem that the rotational speed does not become constant and fluctuates or becomes unstable, and when starting or stopping, it remains the same as before, but when operating at a constant rotational speed The number is required to be constant and stable.

  The present invention solves such a conventional problem, and when operating at a constant rotational speed, the rotational speed is constant and stable, and when starting or stopping, the target is the fastest. An object of the present invention is to provide a brushless DC motor control device capable of reaching the rotational speed.

  On the other hand, when the target speed is reached at the fastest speed, a sudden change in speed may be a problem, and it is required to start at a low speed, stop, or change the speed. .

  The present invention sets a time until the target rotational speed is reached, sets a plurality of target rotational speeds until the target rotational speed is reached, and sequentially changes the target rotational speed to reach the final target rotational speed. Therefore, an object of the present invention is to provide a brushless DC motor control device capable of starting at a low speed, stopping at a low speed, and changing the rotation speed.

  Further, it is required to change the time until the target rotational speed is reached or to manage the time required to reach the target rotational speed.

  The present invention makes it possible to set a plurality of times until the target rotational speed is reached, set a plurality of target rotational speeds until reaching the target rotational speed, and reach the set number of target rotational speeds. Providing a brushless DC motor control device that can change the time to reach the target rotational speed and manage the time to reach the target rotational speed because the target rotational speed is changed sequentially based on time to reach the final target rotational speed The purpose is to do.

  In addition, when a plurality of brushless DC motors are interlocked, not only the target rotational speed is kept constant and stable, but also the rotational speed is required to be accurate. For this purpose, the time interval of the position detection signal must be accurately detected. Is required.

  An object of the present invention is to provide a brushless DC motor control device that can increase the accuracy of the target rotation speed by increasing the accuracy of measurement of the time interval of the brushless DC motor control device.

  In addition, when multiple rollers driven by a brushless DC motor controller are linked at a fixed rotation speed, the interval is reduced and more loads are transported, and when starting or stopping, the load reaches the target rotation speed at the fastest speed. In addition, it is required to reach the target rotational speed at a low speed so as not to fall.

  In the present invention, when a plurality of rollers driven by a brushless DC motor control device are interlocked at a constant rotational speed, the interval is narrowed to transport more loads, and the load reaches the target rotational speed at the maximum speed when starting or stopping. It is an object of the present invention to provide a transport device that can reach a target rotational speed at a low speed so that the target rotational speed can be reached without falling down.

  In order to achieve the above object, the brushless DC motor control device of the present invention and the conveying device equipped with the same are provided with time interval averaging means for storing and averaging for one rotation at the mechanical angle of the brushless DC motor. .

  Accordingly, the brushless DC motor control device can absorb the variation in the position and angle of the position detection means and the variation in the magnetization of the rotor at the time of manufacturing the component, and can detect the accurate rotational speed and increase the rotational speed accuracy. Is obtained.

  Another means is that the rotation speed detection means obtains an average value of the time interval of one rotation period for each position detection signal generated from a plurality of position detection elements, detects the rotation speed by the average value of the time intervals, The rotation speed feedback means changes the DC voltage applied to the stator winding based on the rotation speed output from the rotation speed detection means and the cycle for changing the DC voltage applied to the stator winding predetermined for each target rotation speed. Output judging means for judging whether to do or not.

  According to the present invention, the number of rotations is usually detected for each position detection signal and feedback of the number of rotations is performed. Depending on the specific number of rotations, the number of times of feedback of the number of rotations is reduced, and the timing and voltage for detecting the number of rotations A brushless DC motor control device capable of improving the stability of the rotational speed from a low rotational speed to a high rotational speed by arbitrarily changing the timing of feedback is obtained.

  In another means, the rotational speed feedback means provides a first threshold value and a second threshold value lower than the first threshold value at a rotational speed lower than the target rotational speed, and the rotational speed is increased. In this case, when the rotational speed is lower than the first threshold, the rotational speed obtained from the time interval measuring means is selected, and when the rotational speed is high, the rotational speed obtained from the time interval averaging means is selected and rotated. When the rotation speed is lower, the rotation speed obtained from the time interval measuring means is selected when the rotation speed is lower than the second threshold value, and when the rotation speed is higher, the rotation speed obtained from the time interval averaging means is selected. A gain changing means for changing a rate of change of the DC voltage applied to the stator with respect to the difference in rotation speed when selecting the rotation speed selection means and the time interval measurement means to be selected and when selecting the time interval averaging means. It is provided.

  According to the present invention, when starting up or increasing the target rotational speed, the target rotational speed is reached at the fastest speed, and when operating at a constant rotational speed, the brushless speed is constant and stable. A DC motor control device is obtained.

  Another means is that when the rotational speed feedback is provided with a first threshold value and a second threshold value higher than the first threshold value at a rotational speed higher than the target rotational speed, the rotational speed is decreasing. When the rotational speed is higher than the first threshold, the rotational speed obtained from the time interval measuring means is selected. When the rotational speed is low, the rotational speed obtained from the time interval averaging means is selected, and the rotational speed is selected. When the rotation speed is lower than the second threshold value, the rotation speed obtained from the time interval averaging means is selected, and when the rotation speed is high, the rotation speed obtained from the time interval measurement means is selected. Gain changing means for changing a change rate of the DC voltage applied to the stator with respect to the difference in the rotation speed when selecting the rotation speed selecting means and the time interval measuring means to be selected and when selecting the time interval averaging means. It is a thing.

  According to the present invention, when stopping or reducing the target rotational speed, the target rotational speed is reached at the fastest speed, and when operating at a constant rotational speed, the brushless speed can be kept constant and stable. A DC motor control device is obtained.

  Further, the other means has a plurality of predetermined target rotational speeds, and matches the target rotational speed by the rotational speed feedback means for a predetermined time in order of decreasing rotational speed until reaching the required target rotational speed, This is provided with a rotational speed sequential increase means for sequentially increasing the target rotational speed to reach the required target rotational speed.

  According to the present invention, it is possible to obtain a brushless DC motor control device that can be sequentially activated to increase the rotational speed by increasing the rotational speed.

  According to another means, a plurality of predetermined target rotational speeds are provided, and the target rotational speed is matched by the rotational speed feedback means for a predetermined time in order from the highest rotational speed until the required target rotational speed is reached. And a rotational speed sequential lowering unit that sequentially decreases the target rotational speed to reach the required target rotational speed.

  According to the present invention, it is possible to obtain a brushless DC motor control device capable of sequentially decreasing the rotational speed to stop or decrease the rotational speed.

  According to another means, the speed increasing means sequentially increases the time required to reach the target rotational time by controlling the target rotational speed from a lower target rotational speed to a higher target rotational speed every predetermined time. An ascending arrival time setting command for inputting a specified ascending arrival time setting command and setting the time of each target rotation speed from the number of times the target rotation speed is changed and the arrival time is provided.

  According to the present invention, a brushless DC motor control device capable of reaching the target rotational speed by sequentially increasing the target rotational speed by the set arrival time is obtained.

  According to another means, the rotational speed successive lowering means controls the time to reach the target rotational time by controlling from a high target rotational speed to a lower target rotational speed at predetermined time intervals. A descent arrival time setting command is input to input a specified descent arrival time setting command and set the time of each target rotation speed based on the number of times the target rotation speed is changed and the arrival time.

  According to the present invention, it is possible to obtain a brushless DC motor control device that can reach the target rotational speed by sequentially reducing the target rotational speed by the set arrival time.

  According to another means, a time interval measuring means having a high accuracy with a time measuring accuracy of 0.1% or less is provided.

  According to the present invention, since the time interval measuring means can measure with a high accuracy of 0.1% or less, a brushless DC motor control device with a target rotational speed accuracy of 1% or less is obtained.

  Another means is a conveying device equipped with a brushless DC motor control device.

  According to the present invention, when a plurality of rollers driven by a brushless DC motor control device are interlocked at a constant rotation speed, a larger interval is transported with a narrower interval, and the load is the fastest when starting or stopping. A conveying device that can reach the target rotational speed or reach the target rotational speed at a low speed so as not to fall down is obtained.

  According to the present invention, it is possible to absorb the variation in position and angle and the variation in the magnetization of the rotor in component mounting at the time of manufacturing the position detection means, and it is possible to increase the accuracy of the rotational speed by detecting the accurate rotational speed. A brushless DC motor control device can be provided.

  Normally, the number of rotations is detected for each position detection signal, and the number of rotations is fed back depending on the specific number of rotations. Therefore, it is possible to provide a brushless DC motor control device that can increase the stability of the rotational speed from a low rotational speed to a high rotational speed.

  Also, the brushless DC motor control that can stabilize at a constant rotational speed when operating at a constant rotational speed, and can reach the target rotational speed at the maximum speed when starting up or when the rotational speed increases. Equipment can be provided.

  In addition, when operating at a constant rotation speed, the rotation speed is constant and stable, and when stopping or when the rotation speed decreases, the brushless can stop at the fastest speed or reach the target rotation speed. A DC motor control device can be provided.

  Further, it is possible to provide a brushless DC motor control device capable of starting up or increasing the rotational speed by sequentially increasing the rotational speed.

  Further, it is possible to provide a brushless DC motor control device that can sequentially decrease the rotational speed to stop or decrease the rotational speed.

  Also, increase the target rotational speed by the set arrival time in order to start and reach the target rotational speed, reach another target rotational speed, or change the time to reach the target rotational speed It is possible to provide a brushless DC motor control device capable of

  In addition, the brushless DC motor control device that can lower the target rotational speed sequentially by the set arrival time to stop, reach another target rotational speed, or change the time to reach the target rotational speed Can provide.

  Further, it is possible to provide a brushless DC motor control device in which the rotational speed is constant and stable and the rotational speed is highly accurate.

  In addition, when multiple rollers driven by a brushless DC motor controller are linked at a constant rotation speed, more intervals are transported with a narrower interval, and the load reaches the target rotation speed at the maximum speed when starting or stopping. In addition, it is possible to provide a transfer device that can reach the target rotational speed at a low speed so as not to fall.

  The invention according to claim 1 of the present invention is generated from a rotor in which N-pole and S-pole magnets are alternately applied to the surface, a plurality of position detection elements mounted on an electric circuit board, and the position detection elements. Time interval measuring means for measuring and storing the time interval for each position detection signal, and time interval average for storing and averaging the time interval obtained from the time interval measuring means for a period of one rotation at the mechanical angle of the brushless DC motor Rotational speed detection means configured to detect the rotational speed, DC voltage changing means for changing the rotational speed by changing the DC voltage applied to the stator winding, connected to the DC power supply and the plurality of stator windings The switching means for sequentially energizing the DC voltage, and the DC voltage applied to the stator winding according to the difference in the rotational speed by comparing the predetermined target rotational speed with the rotational speed detected by the rotational speed detecting means. Signal to change A rotation speed feedback means for controlling the output to the DC voltage changing means so as to match the target rotation speed, and measuring the time interval of one rotation period at the mechanical angle of the brushless DC motor; The number of rotations can be detected by the average value of the time intervals of one rotation period.

  According to a second aspect of the present invention, the rotational speed detection means obtains an average value of time intervals for one rotation period for each position detection signal generated from a plurality of position detection elements, and the average value of the time intervals. The rotational speed feedback means comprises output judgment means for changing the rotational speed output from the rotational speed detection means and the DC voltage applied to the stator winding, and the output judgment means The stability of the rotational speed can be improved by changing the DC voltage applied to the stator winding for each position detection signal.

  According to a third aspect of the present invention, the rotation speed detecting means obtains an average value of time intervals of one rotation period for each position detection signal generated from a plurality of position detection elements, and the average value of the time intervals. The rotation speed feedback means detects the rotation speed based on the rotation speed output from the rotation speed detection means and the period of changing the DC voltage applied to the stator winding determined in advance for each target rotation speed. Output judgment means for judging whether or not to change the DC voltage applied to the wire, and whether or not to change the DC voltage applied to the stator winding for each position detection signal By changing the cycle to be changed, the stability of the rotational speed can be increased from a low rotational speed to a high rotational speed.

  According to a fourth aspect of the present invention, the rotational speed feedback means provides a first threshold value and a second threshold value lower than the first threshold value at a rotational speed lower than the target rotational speed, When the rotational speed is increasing, the rotational speed obtained from the time interval measuring means is selected when the rotational speed is lower than the first threshold value, and when the rotational speed is high, the rotational speed is obtained from the time interval averaging means. When the number of revolutions is selected and the number of revolutions is decreasing, the number of revolutions obtained from the time interval measuring means is selected when the number of revolutions is lower than the second threshold value, and when the number of revolutions is high, the time interval average is selected. The change of the DC voltage applied to the stator with respect to the difference in the rotation speed when the rotation speed selection means and the time interval measurement means are selected and the time interval averaging means is selected. It is equipped with a gain changing means to change the ratio, and by increasing and decreasing the rotational speed A difference is set in the threshold value, and when the engine is started up or when the rotation speed is lower than the target rotation speed due to change or disturbance, the difference in rotation speed approaches the target rotation speed during operation. By switching the speed detection method and the change rate of the DC voltage applied to the stator, the target speed can be reached at the fastest speed when starting up or when the speed increases. When operating at a constant rotational speed, the rotational speed is constant and stable.

  In the invention according to claim 5 of the present invention, the rotational speed feedback is provided by providing a first threshold value and a second threshold value higher than the first threshold value at a rotational speed higher than the target rotational speed. When the rotation speed is lower than the first threshold value, the rotation speed obtained from the time interval measuring means is selected. When the rotation speed is lower, the rotation speed obtained from the time interval averaging means is selected. When the number of rotations is selected and the number of rotations is increasing, the number of rotations obtained from the time interval averaging means is selected when the number of rotations is lower than the second threshold value, and when the number of rotations is high, the time interval measurement means Ratio of change in DC voltage applied to the stator with respect to the difference in rotation speed when selecting the rotation speed selection means and the time interval measurement means and selecting the time interval averaging means. With gain changing means to change the Setting a difference in the value When stopping at the same time or when the rotational speed is higher than the target rotational speed due to a change in the rotational speed or due to disturbance, the difference between the rotational speed is close to the target rotational speed during operation and the rotational speed difference is small. By switching the detection method of the rotation speed and the rate of change of the DC voltage applied to the stator, when stopping or when the rotation speed falls, it can stop at the fastest speed or reach the target rotation speed In addition, when operating at a constant rotational speed, the rotational speed is constant and stable.

  Further, the invention according to claim 6 of the present invention has a plurality of predetermined target rotational speeds, and the rotational speed feedback means for a predetermined time in order from the low rotational speed until the required target rotational speed is reached. It is equipped with a means for sequentially increasing the rotational speed so that it matches the target rotational speed and sequentially increases the target rotational speed to reach the required target rotational speed. When starting or when increasing the rotational speed, the rotational speed increasing means Thus, it is possible to sequentially increase the rotational speed to start or increase the rotational speed.

  The invention according to claim 7 of the present invention has a plurality of predetermined target rotational speeds, and the rotational speed feedback means for a predetermined time in order from the highest rotational speed until the required target rotational speed is reached. It is equipped with a rotational speed sequential lowering means that matches the target rotational speed and sequentially lowers the target rotational speed to reach the required target rotational speed. When stopping or lowering the rotational speed, the rotational speed lowering means The rotational speed can be lowered and stopped or the rotational speed can be lowered.

  Further, in the invention according to claim 8 of the present invention, the rotation speed sequential increasing means is controlled so as to sequentially increase the target rotation speed from the low target rotation speed every predetermined time, thereby reaching the target rotation time. A rising arrival time setting command is provided to set the target rotation speed based on the number of times the target rotation speed is changed and the arrival time. By sequentially increasing the target rotation speed by the arrival time and reaching the target rotation speed, the time to reach the target rotation speed can be changed.

  Further, in the invention according to claim 9 of the present invention, the rotational speed sequential lowering means is controlled so that the target rotational speed is sequentially decreased from a high target rotational speed to a lower target rotational speed every predetermined time. This is equipped with a descent arrival time setting means that inputs a descent arrival time setting command that specifies the time for the target rotation and sets the time of each target rotation speed based on the number of times the target rotation speed is changed and the arrival time. It is possible to change the time to reach the target rotational speed by sequentially lowering the target rotational speed by the arrival time.

  In the invention according to claim 10 of the present invention, the time interval measuring means has a high accuracy with a time measurement accuracy of 0.1% or less, and the target rotational speed has a high accuracy of 1% or less. be able to.

  Further, according to the eleventh aspect of the present invention, when a plurality of rollers driven by the brushless DC motor control device are interlocked with each other at a constant rotation speed, a larger interval is transported and a large amount of baggage is conveyed. When the vehicle stops, the load can reach the target rotational speed at the fastest speed, or can reach the target rotational speed at a low speed so as not to fall.

(Embodiment 1)
As shown in FIG. 1, a brushless DC motor 102 includes a rotor 106 and an electric circuit board in which U, V, and W of a stator winding 103 and 8 poles of N pole and S pole permanent magnets are alternately applied to the surface. 1 includes three position detecting elements 2a, 2b, and 2c (for example, hall sensors) mounted on the same.

  The position detection elements 2a, 2b, and 2c convert the change of the magnetic pole when the magnet of the rotor 106 changes from the north pole to the south pole and from the south pole to the north pole into electrical signals of H and L, and the position detection signals are micro This is input to the rotational speed detection means 3 of the computer 107.

  The rotation speed detection means 3 detects the rotation speed of the brushless DC motor 102 from the input position detection signal. The position detection signal is input to the time interval measurement means 4 and one signal of the position detection signal changes. The time interval until the other one signal changes is measured, and one rotation of the mechanical angle of the rotor 106, that is, 24 time intervals are stored in the microcomputer 107.

  The time interval averaging means 5 obtains an average value of 24 time intervals stored by the time interval measuring means 4.

  The rotation speed feedback means 6 compares a predetermined target rotation speed with the rotation speed detected by the rotation speed detection means 3 and outputs a signal for changing the DC voltage applied to the stator winding 103 according to the difference in the rotation speed. Output to voltage changing means 109.

  The DC voltage changing means 109 performs PWM modulation based on a signal for changing the DC voltage applied to the stator winding 103 output from the rotation speed feedback means 6 and outputs the result to the drive signal generating means 110. The DC voltage changing means 109 is composed of a triangular wave signal generator and a comparator (detailed explanation is omitted in the figure), and a signal output from the triangular wave generator with a signal output from the rotation speed feedback means 6 as a reference value. Are compared by a comparator to obtain H and L PWM signals based on the period of the triangular wave signal.

  The drive signal generating means 110 captures changes in the position detection signals of the three position detection elements, and sequentially applies the U, V, and W of the stator winding 103 in a predetermined direction and order according to the state of the position detection signals at that time. A signal for changing the DC voltage applied to U, V, W of the stator winding 103 based on the PWM-modulated signal output from the DC voltage changing means 109 is supplied to the drive means 111 while being energized.

  The rotation speed detection means 3, the rotation speed feedback means 6, the DC voltage change means 109, and the drive signal generation means 110 are built in the microcomputer 107.

  The drive means 111 converts the switching element of the switching means 112 into a signal for turning on and off based on the signal output from the drive signal generating means 110 built in the microcomputer 107.

  The switching means 112 is connected to the DC power source 108 and comprises six switching elements Q1, Q2, Q3, Q4, Q5, Q6 and freewheeling diodes D1, D2, D3, D4, D5, D6. The U, V, and W are sequentially energized at a predetermined timing, the DC voltage of the DC power supply 108 is changed, and the brushless DC motor 102 is rotated in addition to the U, V, and W of the stator winding 103.

  Specifically, as shown in FIG. 2, the position detection elements 2a, 2b, and 2c convert the magnetic pole change of the magnet of the rotor 106 into H and L electrical signals to obtain position detection signals Hu, Hv, and Hw. . The brushless DC motor 102 is rotated by the combination of H and L of the switching elements Q1, Q2, Q3, Q4, Q5, and Q6 of the switching means 112 corresponding to the combination of the position detection signals.

  FIG. 3 shows a position detection signal waveform for one rotation at a mechanical angle. As shown in FIG. 3, the position detection signal is mounted on the electric circuit board 1 fixed to the stator 3. Variations in the time intervals of the position detection signals occur due to variations in the mounting positions of components during the manufacture of the two position detection elements 2a, 2b, and 2c, and variations in the magnetization of the N and S poles of the rotor 106. The intervals are not equal. Since the variation in the time interval is repeatedly generated at a period for each rotation, the variation can be absorbed by averaging the time intervals of the position detection signals for one rotation.

  The time interval measuring means 4 performs a control processing operation based on the flowchart shown in FIG. 4 and describes steps S1 to S2. The time interval t is measured each time one of the position detection signals of the three position detection elements changes and the next one changes (step S1). For example, the time interval t when one of the position detection signals changes and the next one changes changes to the time interval t1 and is stored in the microcomputer 107 (step S2). Thereafter, one rotation of the mechanical angle, that is, 24 time intervals are similarly stored as time intervals t2, t3, t4,.

  The time interval averaging means 5 performs a control processing operation based on the flowchart shown in FIG. 5, and explains steps S3 to S4. From the 24 time intervals stored by the time interval measuring means 4, the average value T of the time intervals is obtained from Equation 3.

  The rotation speed detection means 3 performs a control processing operation based on the flowchart shown in FIG. 6 and explains steps S5 to S6. Using the average value T output by the time interval averaging means 5, the rotational speed NT is obtained by Equation 4 (steps S5 and S6).

  The rotation speed feedback means 6 performs control processing based on the flowchart shown in FIG. 7, and explains steps S7 to S10. FIG. 8 shows the rotational speed difference from the target rotational speed. The target rotational speed Nm determined in advance is compared with the rotational speed NT detected by the time interval averaging means 5 of the rotational speed detecting means 3. The difference Nd in the rotational speed is obtained from 5 (step S7).

  Assuming that the rate of change of the voltage corresponding to a predetermined rotation speed difference Nd is gain A and the DC voltage applied to the stator winding is V, the voltage Vd for changing the DC voltage with respect to the rotation speed difference Nd is Is obtained by Equation 6 (step S8, step S9).

  The voltage Vd for changing the DC voltage increases as the difference Nd in the rotational speed increases with respect to the target rotational speed Nm. Accordingly, when the rotational speed NT becomes lower than the target rotational speed Nm and the rotational speed difference Nd increases, the target rotational speed is increased by the amount corresponding to the voltage Vd to be changed with respect to the DC voltage applied to the stator winding. The number of revolutions is controlled so as to approach the number Nm. Further, when the rotational speed NT becomes higher than the target rotational speed Nm and the rotational speed difference Nd increases, the target rotational speed is reduced by a voltage Vd that is changed with respect to the DC voltage applied to the stator winding. The rotational speed is controlled so as to approach the number Nm (step S10).

  For example, when the target rotation speed is set to 0.1 when the voltage corresponding to the rotation speed difference of 60 r / min and the difference in rotation speed is 5 r / min is set to 0.1, the time interval for one rotation, that is, 24 time intervals are set. In the case of 923.1 ms, the average value T of the time interval is 16.0 ms according to Equation 3. The rotational speed at this time is 65 r / min from Equation 4, and the rotational speed difference Nd is 5 r / min. Therefore, the voltage Vd for changing the DC voltage with respect to the rotational speed difference Nd is 0.5 V according to Equation 6, and is decreased by 0.5 V with respect to the DC voltage with respect to the stator difference Nd, so that the constant rotational speed is achieved at the target rotational speed. Control as follows.

  In the first embodiment, the rate of change of the voltage corresponding to the difference in rotation speed of 5 r / min is set to 0.1. However, in practice, if the optimum value of the rate of change of voltage with respect to the difference in rotation number is set. good.

  In this way, the rotational speed control is performed so as to approach the target rotational speed Nm by changing the DC voltage applied to the stator winding 103 for each position detection signal generated from the position detection element.

(Embodiment 2)
In FIG. 9, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 10 shows a time interval for one rotation to be averaged. As shown in FIG. 10, the rotation speed detection means 103 is a machine in which the time interval t is stored by the time interval averaging means 5 every time one of the position detection signals of the three position detection elements changes and the next one changes. The average value T of the time intervals and the rotational speed NT are obtained from Equations 3 and 4 from one time at a corner, that is, 24 time intervals (time intervals t1 to t24).

  As shown in FIG. 7, the rotation speed feedback means 6 compares the target rotation speed Nm with the rotation speed NT each time one of the position detection signals of the three position detection elements changes and the next one changes. A voltage Vd for changing the DC voltage applied to the stator winding 102 in accordance with the number difference Nd is obtained by Expression 5 and Expression 6.

  The output determination means 7 performs a control processing operation based on the flowchart shown in FIG. 11, and will explain steps S11 to S12.

  When one of the position detection signals of the three position detection elements 2a, 2b, and 2c is changed, the voltage is changed by the voltage Vd that is changed with respect to the DC voltage applied to the stator winding 103. When there is no change in the position detection signals of the three position detection elements 2a, 2b, and 2c, the DC voltage applied to the stator winding 103 is not changed (steps S11 and S12).

  Similar to the first embodiment, for example, when the target rotation speed is set to 60 r / min and the voltage change rate corresponding to the difference in rotation speed of 5 r / min is set to 0.1, the time for one rotation When the interval, that is, the 24 time intervals is 923.1 ms, the average value T of the time intervals is 16.0 ms according to Equation 3. The rotational speed NT is 65 r / min from Equation 4, and the difference in rotational speed from the target rotational speed is 5 r / min from Equation 5. The voltage Vd for changing the DC voltage with respect to the rotational speed difference Nd is 0.5 V from Equation 6. At this time, when one of the position detection signals of the three position detection elements 2a, 2b, 2c is changing, the voltage 0.5V to be changed with respect to the DC voltage applied to the stator winding 103 is decreased, When there is no change in the position detection signals of the three position detection elements 2a, 2b, and 2c, the DC voltage applied to the stator winding 103 is not changed.

(Embodiment 3)
In FIG. 9, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  FIG. 10 shows a time interval for one rotation to be averaged. As shown in FIG. 10, the rotational speed detection means 3 is a machine in which the time interval t is stored by the time interval averaging means 5 every time one of the position detection signals of the three position detection elements changes and the next one changes. The average value T of the time intervals and the rotational speed NT are obtained from Equations 3 and 4 from one time at a corner, that is, 24 time intervals (time intervals t1 to t24).

  Further, as shown in FIG. 7, the rotational speed feedback means 6 has a DC voltage applied to a predetermined stator winding every time one of the position detection signals of the three position detection elements changes and the next one changes. Is compared with the period for changing the DC voltage, and at the period for changing the DC voltage, the target rotation speed Nm and the rotation speed NT are compared, and the voltage Vd for changing the DC voltage applied to the stator winding 103 according to the difference Nd in the rotation speed Is obtained by Equation 5 and Equation 6.

  The output determination means 7 performs a control processing operation based on the flowchart shown in FIG. 12, and will explain steps S13 to S17.

  When the timer for changing the DC voltage is stopped and the timer for changing the DC voltage is not up (step S14), a cycle for changing the DC voltage applied to the predetermined stator winding 103 is acquired (step S15). ), A period timer for changing the DC voltage based on the period for changing the DC voltage is started (step S16). When the timer for changing the DC voltage has expired (in the cycle of changing the DC voltage) (step S14), the voltage is changed by the voltage Vd to be changed with respect to the DC voltage applied to the stator winding 103. (Step S17). When the timer for changing the DC voltage is not stopped (when the cycle for changing the DC voltage has not elapsed), the DC voltage is not changed (step 13).

  For example, the cycle for changing the DC voltage applied to the stator winding 103 is set to 32.0 ms, the target rotation speed is set to 60 r / min, and the voltage change ratio corresponding to the rotation speed difference of 5 r / min is set to 0.1. When the time interval for one rotation, that is, 24 time intervals is 923.1 ms, the average value T of the time intervals is 16.0 ms from Equation 3. The rotational speed NT is 65 r / min from Equation 4, and the difference in rotational speed from the target rotational speed is 5 r / min from Equation 5. The voltage Vd for changing the DC voltage with respect to the rotational speed difference Nd is 0.5 V from Equation 6. At this time, if the cycle for changing the DC voltage applied to the stator winding 103 has not elapsed, the DC voltage is changed, and if the cycle for changing the DC voltage applied to the stator winding 103 has not yet elapsed, The DC voltage is not changed.

  In the second embodiment, the cycle for changing the DC voltage applied to the stator winding 103 is 32.0 ms. However, in practice, the cycle for changing the DC voltage applied to the stator winding 103 is appropriately set to an optimum value. For example, it may be 64.0 ms.

(Embodiment 4)
In FIG. 13, the same parts as those in any of Embodiments 1 to 3 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 14, the rotational speed comparison means 8 of the rotational speed feedback means 6 provides a first threshold value Nk1 and a second threshold value Nk2 at a rotational speed lower than the target rotational speed Nm. Further, the rotational speed Nt corresponding to the time interval t obtained from the time interval measuring means 4 is calculated by Equation 7.

  The control processing operation steps S16 to S21 will be described based on the flowchart shown in FIG. The rotation speed selection means 9 compares the first threshold value Nk1 and the second threshold value Nk2 with the rotation speed Nt and the rotation speed NT, and selects Nt when the rotation of Nt <Nk2 is low (step S16). And, when the rotational speed of Nk1> Nt ≧ Nk2 or Nk1> NT ≧ Nk2 is intermediate, Nt is selected because the rotational speed has increased when Nt was selected last time (step S17, step S18). And when NT <Nk2 is not selected and NT <Nk2 is selected last time, Nt is selected (step S18, step S19 and step S20). When NT <Nk1, NT is selected (step S18, step S19, step S20). S21) When the rotational speed of NT ≧ Nk1 approaches the target rotational speed Nm, NT is selected (step S17, step S). 9 and step S21).

  Next, the ratio of change in the voltage applied to the optimum stator winding 103 of the rotational speed feedback means 6 when the target rotational speed is increased by starting up or by changing the rotational speed and the rotational speed is rising at the fastest speed. Gain AKt is obtained. Further, the optimum gain AKT for changing the voltage applied to the stator winding 103 when the rotational speed is controlled to be constant while approaching the target rotational speed Nm is obtained.

  The control processing operation steps S22 to S24 will be described based on the flowchart shown in FIG. The gain changing means 10 of the rotational speed feedback means 6 selects the gain AKt when the rotational speed Nt is selected (steps S22 and S23), and selects the gain AKT when the rotational speed NT is selected. (Step S22 and Step S24).

  In the above-described configuration, when the target rotational speed Nm is increased and the rotational speed Nt is increased by starting or changing the rotational speed, the rotational speed is Nt, and the gain of the rate of change of the voltage applied to the stator winding 103 When Akt is selected and the target rotational speed Nm is approached during operation, NT is selected as the rotational speed, and Akt is selected as the gain of the voltage determining means. Further, when the rotational speed of Nk1> Nt ≧ Nk2 or Nk1> NT ≧ Nk2 is intermediate, the previous rotational speed Nt or NT is selected, so that hysteresis is provided when switching between the rotational speed Nt and the rotational speed NT. .

  For example, the target rotational speed is 60 r / min, the threshold value Nk1 is 55 r / min, the threshold value Nk2 is 40 r / min, and the gains Akt and AkT of the change rate of the voltage applied to the stator winding 103 are each 0. 5 and 0.1 are set.

  When the rotational speed rises and the rotational speed Nt changes from 35 r / min to 57 r / min, NT ≧ Nk1 is satisfied, and NT is selected as the rotational speed, and the rate of change in the voltage applied to the stator winding 103 The gain is selected as AkT. Thereafter, when the rotational speed decreases and the rotational speed NT changes from 57 r / min to 53 r / min, Nk1> NT ≧ Nk2 is satisfied, and the rotational speed is selected as NT, and the voltage applied to the stator winding 103 For the change rate gain of AkT = 0.1 is selected. Thereafter, when the rotational speed NT is changed from 53 r / min to 35 r / min, NT <Nk2 is established, the rotational speed is selected as Nt, and the gain of the rate of change of the voltage applied to the stator winding 103 is Akt. = 0.5 is selected.

  In the fourth embodiment, the target rotational speed is 60 r / min, threshold value Nk1 is 55 r / min, threshold value Nk2 is 40 r / min, gain Akt of the rate of change of voltage applied to stator winding 103, and Although AkT is 0.5 and 0.1, respectively, in practice, an optimum value for each numerical value may be set.

  In this way, hysteresis can be provided when switching between the rotational speed Nt and the rotational speed NT.

(Embodiment 5)
In FIG. 13, the same parts as those in any of Embodiments 1 to 4 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 17, the rotational speed comparison means 8 of the rotational speed feedback means 6 provides the third threshold value Nk3 and the fourth threshold value Nk4 at a rotational speed higher than the target rotational speed Nm.

  Control processing operation steps S25 to S30 will be described based on the flowchart shown in FIG.

  The rotation speed selection means 9 compares the third threshold value Nk3 and the fourth threshold value Nk4 with the rotation speed Nt and the rotation speed NT, and selects Nt when the rotation speed of Nt> Nk4 is high (step S25 and step S29), when the rotational speed of Nk4 ≧ Nt> Nk3 or Nk4 ≧ NT> Nk3 is intermediate, Nt is selected because the rotational speed has increased when Nt was selected last time (step S26, step S29). S27 and step S29), when NT was previously selected and NT> Nk4, Nt was selected (step S27, step S28 and step S29), and when NT> Nk4 was not selected, NT was selected (step S27, step S28 and step S28). In step S30), when the rotational speed of NT> NK3 approaches the target rotational speed Nm, NT is selected (step S26, scan). -Up S28, step S30).

  Next, the ratio of the change in the voltage applied to the optimum stator winding 103 of the rotation speed feedback means 6 when the target rotation speed is lowered due to a change in the rotation speed or when the rotation speed is decreasing at the highest speed. The gain AKt is obtained. Further, the gain AKT is obtained as the ratio of the change in the voltage applied to the optimal stator winding 103 when the rotational speed is controlled at a constant value approaching the target rotational speed Nm.

  The control processing operation steps S22 to S24 will be described based on the flowchart shown in FIG.

  The gain changing means 10 of the rotational speed feedback means 6 selects the gain AKt when the rotational speed Nt is selected (steps S22 and S23), and selects the gain AKT when the rotational speed NT is selected. (Step S22, Step S24).

  In the above configuration, when the target rotational speed Nm is lowered and the rotational speed Nt is lowered when starting or when the rotational speed is changed, the rotational speed is Nt, and the rate gain for changing the voltage applied to the stator winding 103 is When Akt is selected and approaching the target rotational speed Nm during operation, the rotational speed is NT, and the gain of the rate of voltage change applied to the stator winding 103 is selected as AkT. In addition, when the rotation speed of Nk4 ≧ Nt> Nk3 or Nk4 ≧ NT> Nk3 is intermediate, the previous rotation speed Nt or NT is selected, so that hysteresis is provided when switching between the rotation speed Nt and the rotation speed NT. Become.

  For example, the target rotational speed is 60 r / min, the threshold value Nk3 is 65 r / min, the threshold value 4 is 80 r / min, and the gains Akt and AkT of the change rate of the voltage applied to the stator winding 103 are each set to 0. 5 and 0.1 are set.

  When the rotational speed decreases and the rotational speed Nt changes from 85 r / min to 63 r / min, NT ≦ Nk is satisfied, and NT is selected as the rotational speed, and the rate of change in the voltage applied to the stator winding 103 The gain is selected as AkT. Thereafter, when the rotational speed increases and the rotational speed NT changes from 63 r / min to 67 r / min, Nk4 ≧ NT> Nk3 is established, and the rotational speed is selected as NT, and the voltage applied to the stator winding 103 For the change rate gain, AkT is selected. Thereafter, when the rotational speed NT is changed from 67 r / min to 85 r / min, NT> Nk4 is established, the rotational speed is selected as Nt, and the gain of the rate of change of the voltage applied to the stator winding 103 is Akt. Select.

  In the eighth embodiment, the target rotational speed is 60 r / min, the threshold value Nk3 is 65 r / min, the threshold value Nk4 is 80 r / min, the gain Akt of the rate of change of the voltage applied to the stator winding 103, and Although AkT is 0.5 and 0.1, respectively, in practice, an optimum value for each numerical value may be set.

  In this way, hysteresis can be provided when switching between the rotational speed Nt and the rotational speed NT.

(Embodiment 6)
In FIG. 19, the same parts as those in any of Embodiments 1 to 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 20, when the target rotational speed is determined from stop to Nm by operation, stop, and speed commands, the rotational speed sequential increase means 11 has a plurality of target rotational speeds from low speed to high speed in advance. The target rotational speed Nm1, Nm2, Nm3,..., Nmn is selected from the slowest target rotational speed among them, and the target rotational speed is output for a certain period in order of the lower target rotational speed, and finally the target rotational speed Nm Is output to the threshold value 10 of the rotation speed feedback means.

  Control processing operation steps S31 to S35 will be described based on the flowchart shown in FIG. The target rotational speed Nmn is compared with the target rotational speed Nm (step S31). When Nmn <Nm, n = 0 is set at the time of stop, n is increased by 1, n = 1 is selected (step S32, step S33), and operation is performed with the target rotational speed set to Nm1 for a certain period (step S34). ). After a predetermined time has elapsed, Nmn and Nm are compared again (step S31). When Nmn <Nm, n is incremented by 1 to n = 2 (step S32), and thereafter the same processing is repeated. When Nmn ≧ Nm, the rotational speed Nm is selected assuming that the target rotational speed has been reached (steps S31 and S35).

  The threshold value is output to the rotational speed selection means 9 for each target rotational speed, the DC voltage applied to the stator winding 103 of the rotational speed feedback means 6 is determined, and is output from the microcomputer 107.

  In the above configuration, when the target rotational speed is determined to be Nm from the stop, the rotational speed sequential increase means 11 sequentially shifts from the slowest target rotational speed predetermined every predetermined time to the higher target rotational speed to obtain the final target rotational speed. Several Nm can be reached.

  For example, the rotational speed sequential increase means 11 has ten target rotational speeds of Nm1 (500 r / min), Nm2 (1000 r / min), Nm3 (1500 r / min),..., Nm10 (5000 r / min), for example. , Nm is set to, for example, 2800 r / min, and a lower rotational speed, for example, Nm1, Nm2,... Nm5 (2500 r / min) is selected and increased every predetermined time, for example, every second. After 4 seconds, a target rotational speed Nm5 of 2500 r / min is output for 1 second, and finally a target rotational speed Nm of 2800 r / min is output.

  In the sixth embodiment, the configuration and operation of the rotational speed sequential increase 19 when the target rotational speed is reached after startup and activation are described. However, the target rotational speed is changed to a higher target rotational speed during operation, and the rotational speed is increased. Even when the number rises, it can be implemented with the same configuration and action, and no difference occurs.

  By doing in this way, it is possible to shift from the slowest target rotational speed set in advance every predetermined time to a higher target rotational speed and reach the final target rotational speed Nm.

(Embodiment 7)
In FIG. 22, the same parts as those in any of Embodiments 1 to 6 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 23, when the stop is determined by the operation, stop, and speed command, the rotation speed sequential descending means 12 has a plurality of target rotation speeds from low speed rotation to high speed rotation in advance, and is closest to Nm and is low. The target rotational speed is selected from the target rotational speed to the lowest target rotational speed, the target rotational speed is output for a certain period in order of the higher target rotational speed, and the lowest target rotational speed is output to the threshold value of the rotational speed feedback means and then stopped.

  Control processing operation steps S36 to S40 will be described based on the flowchart shown in FIG. The current target rotational speed Nmn is compared with 0 of the target rotational speed Nm to be stopped (step S36). When Nmn> Nm, n is decremented by 1 and Nmn-1 is selected (step S37, step S38), and the operation is performed with the target rotational speed set to Nn-1 for a certain period (step S39). After a predetermined time has elapsed, Nmn and Nm are compared again (step S36). When Nmn ≦ Nm, n is decreased by 1 to Nmn-2 (steps S37 and S38), and thereafter the same processing is repeated. After a predetermined time has elapsed, the previous n is acquired and Nmn and Nm are compared again. When Nmn ≦ Nm, the target rotational speed is reached and the rotational speed Nm is selected, that is, stopped (steps S36 and S40).

  As the threshold value, a threshold value for each target rotation speed is output to the rotation speed selection means 9, a DC voltage applied to the stator winding 103 of the rotation speed feedback means 6 is determined, and is output from the microcomputer 107.

  In the above configuration, when the target rotational speed is determined to be stopped from Nm, the rotational speed sequential descending means 12 shifts from a lower target rotational speed to a lower target rotational speed sequentially closest to a predetermined Nm every predetermined time, The final target rotational speed Nm, that is, it can be stopped.

  For example, the rotational speed sequential lowering means 12 has ten target rotational speeds of Nm1 (500 r / min), Nm2 (1000 r / min), Nm3 (1500 r / min),..., Nm10 (5000 r / min), for example. , Nm is set to 2800 r / min, for example, and a lower rotation speed, for example, Nm1, Nm2,... Nm5 (2500 r / min) is selected, and after a target rotation speed of 2500 r / min of the target rotation speed Nm5 is output first, Decrease every predetermined time, for example, every second. After 4 seconds, a target rotational speed Nm1 of 500 r / min is output for 1 second, and finally stopped.

  In the seventh embodiment, the configuration and operation of the rotational speed sequential lowering means 12 when stopping are described. However, the same applies when the target rotational speed is changed to a lower rotational speed during operation and the rotational speed decreases. It can be implemented with configuration and action, and does not make a difference.

  By doing in this way, it is possible to shift from the lowest target rotational speed closest to Nm predetermined every predetermined time to the lower target rotational speed sequentially, and to stop the final target rotational speed Nm, that is, stop.

(Embodiment 8)
In FIG. 25, the same portions as those in any of Embodiments 1 to 7 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 26, when the target rotation speed is determined to be Nm from the stop by the operation, stop, and speed commands, the rising arrival time setting means 13 selects the arrival time TJS from the rising arrival time instruction, and the rotation speed sequential increasing means. The time Tjs for each target rotational speed is determined from the stage number GJ of the target rotational speed closest to Nm from the slowest target rotational speed selected from 11, and is output to the rotational speed sequentially increasing means 11.

  Control processing operation steps S41 to S43 will be described based on the flowchart shown in FIG. The arrival time TJS and the number of steps GJ from the slowest target rotational speed Nm selected by the rotational speed sequential increase means 11 to the closest and lower target rotational speed are acquired from the ascending arrival time command (steps S41 and S42). The output time Tjs for each target rotational speed is calculated from Equation 8 (step S43).

  The rotation speed sequential increase means 11 outputs the target rotation speed for a certain period of time Tjs in order of the lower rotation speed, and is controlled so that the arrival time TJS is reached when the target rotation speed Nm is finally reached.

  In the above configuration, when the target rotational speed is determined to be Nm from the stop, the rotational speed sequential increase means 11 sequentially increases the target from the slowest target rotational speed that is predetermined every output time Tjs determined by the rising arrival time means. The target rotational speed Nm can be reached after the TJS time has elapsed since the transition to the rotational speed.

  For example, as in the sixth embodiment, Nm is set to 2800 r / min, for example, and a lower rotation speed, for example, Nm1, Nm2,... Nm5 is selected, the target rotation speed number GJ is 5, and the arrival time TS is 2. When 5 seconds is set, Tjs = 0.5 seconds, the target rotational speed increases every 0.5 seconds, and after 2 seconds, the target rotational speed Nm5 of 2500 r / min is output for 0.5 seconds, and finally 2800 r. A target rotational speed Nm of / min is output.

  In the embodiment, the configuration and operation of the rising arrival time setting means 13 when the target rotational speed is reached after startup is described. However, the target rotational speed is changed to a higher target rotational speed during operation, and the rotational speed increases. In this case, it can be carried out with the same configuration and action, and no difference occurs.

  By doing in this way, the rotation speed sequential increase means sequentially shifts from the slowest target rotation speed predetermined for each output time Tjs determined by the increase arrival time means to the higher target rotation speed, and finally the TJS time. After the elapse of time, the target rotational speed Nm can be reached.

(Embodiment 9)
In FIG. 28, the same parts as those in any one of Embodiments 1 to 8 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 29, when the target rotational speed is determined to be stopped from Nm by operation, stop, and speed commands, the descending arrival time setting means 14 selects the arrival time TKS based on the descending arrival time instruction, and the rotational speed sequential descending means. The output time Tks for the angular target rotational speed is determined from the step number GK of the lowest target rotational speed from the lowest target rotational speed selected near 12 to the lowest target rotational speed, and is output to the rotational speed sequential lowering means 12.

  Control processing operation steps S44 to S46 will be described based on the flowchart shown in FIG. A step number GK from the lowest target rotational speed to the lowest target rotational speed closest to the arrival time TKS and the target rotational speed Nm selected by the rotational speed sequential descending means 12 is acquired from the descending arrival time command (step S44, step S45). ), The output time Tks for each target rotational speed is calculated from Equation 9 (step S46).

  The rotational speed sequential lowering means 12 sequentially outputs the target rotational speed from the lowest target rotational speed closest to Nm to the lower target rotational speed for a certain period of time Tks, and finally stops at the target rotational speed Nm, that is, after the TKS time has elapsed. Can be reached.

  For example, as in the seventh embodiment, Nm is set to 2800 r / min, for example, and a lower rotational speed, for example, Nm1, Nm2,... Nm5 is selected, the target rotational speed number GK is 5, and the arrival time TS is 2. If 5 seconds is set, Tks = 0.5 seconds. Initially, the target rotational speed Nm5 of 2500 r / min is output for 0.5 seconds, and then the target rotational speed decreases every 0.5 seconds. After 2 seconds, 500 r / min. After the target rotational speed Nm1 of min is output for 0.5 seconds, it stops at the end.

  Although the present embodiment describes the configuration and operation of the descent arrival time setting means 14 when reaching the stop from the target revision variable, the target rotation speed is changed to a lower target rotation speed during operation, and the rotation Even when the number is lowered, it can be implemented with the same configuration and operation, and no difference is caused.

  In this way, the rotational speed sequential lowering means sequentially outputs the target rotational speed from the lowest target rotational speed closest to Nm to the lower target rotational speed for a certain period of time Tks, and finally after the TKS time has elapsed. The rotational speed Nm, that is, the stop can be reached.

(Embodiment 10)
As shown in FIG. 31, the microcomputer 107 is configured to process each specification by inputting a clock 15 from the outside. For example, the time interval measuring unit 4 includes a plurality of positions of the position detecting unit 4. The time interval from when one of the detection signals changes until the other changes is also directly measured. Accordingly, when a crystal oscillator having an accuracy of 0.1% or less is used for the clock 15, the accuracy of the time interval of the position detection signal is also 0.1 or less.

  Actually, the rotational speed feedback is performed to change the DC voltage applied to the stator winding 103 so that the difference in rotational speed from the target rotational speed is 0.3% to 0.9%. By making the accuracy of the time interval of the position detection signal 0.1% or less, the rotational speed difference with respect to the target rotational speed becomes 1% or less.

  With this configuration, the accuracy of the time interval of the position detection signal is 0.1% or less, so the target rotational speed is as high as 1% or less.

  In this way, when a crystal oscillator with a clock accuracy of 0.1% or less is used, the accuracy of the time interval of the position detection signal is also 0.1 or less. Can be.

(Embodiment 11)
As shown in FIG. 32 and FIG. 33, an example of a conventional roller and transport device is described, and thus the detailed description is omitted. The brushless DC motor control device according to any one of the first to tenth embodiments is mounted, and a conveyance device using a roller incorporating the brushless DC motor connected thereto is used.

  By doing this, the interval is reduced and more packages are conveyed, and when starting or stopping, the packages reach the target rotation speed at the fastest speed, or conversely, the target rotation speed is set at a low speed so as not to fall down. Or can be reached.

  The present invention can also be applied to applications such as a transport device or a ventilation fan equipped with a brushless DC motor control device that is used with the rotational speed accurately kept constant.

Configuration diagram of brushless DC motor control apparatus according to Embodiment 1 of the present invention Switching waveform diagram of switching element based on same position detection signal The figure which shows the time interval for 1 rotation with the same mechanical angle Flow chart in the same time interval measuring means Flow chart in the same time interval averaging means Flowchart in the same rotation speed detection means Flowchart in the same rotation speed feedback means Diagram showing the relationship between the target speed and the speed threshold Configuration diagram of brushless DC motor control device according to second and third embodiments of the present invention The figure which shows the time interval for 1 rotation to equalize The flowchart in the output judgment means of Embodiment 2 of this invention The flowchart in the output judgment means of Embodiment 3 of this invention Configuration diagram of brushless DC motor control apparatus according to embodiments 4 and 5 of the present invention Diagram showing the relationship between the target speed and the speed threshold Flowchart in the same rotation speed detection means Flowchart in gain changing means of same rotation speed feedback means Diagram showing the relationship between the target speed and the speed threshold Flowchart in the same rotation speed detection means Configuration diagram of brushless DC motor control apparatus according to Embodiment 6 of the present invention The figure which showed operation of the brushless DC motor control device Flowchart in means for sequentially increasing the rotation speed Configuration diagram of a brushless DC motor control device according to a seventh embodiment of the present invention. The figure which showed operation of the brushless DC motor control device Flowchart in the same rotation speed sequential lowering means The block diagram of the brushless DC motor control apparatus of Embodiment 8 of this invention The figure which showed operation of the brushless DC motor control device Flow chart in the rise arrival time setting means The block diagram of the brushless DC motor control apparatus of Embodiment 9 of this invention The figure which showed operation of the brushless DC motor control device Flowchart in the descending arrival time setting means Configuration diagram of a brushless DC motor control device according to a tenth embodiment of the present invention. Configuration diagram of a brushless DC motor built in a conventional roller and its control device Constitutional diagram showing transport equipment with many rollers installed and transport of luggage Configuration diagram of a brushless DC motor control device that counts the same position detection signal and detects the rotation speed The figure which shows the relationship which counts the same position detection signal and detects rotation speed Configuration diagram of a brushless DC motor control device that detects the number of rotations by detecting the time interval of the same position detection signal

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electric circuit board 2a Position detection element 2b Position detection element 2c Position detection element 3 Rotation speed detection means 4 Time interval measurement means 5 Time interval average means 6 Rotation speed feedback means 101 DC motor control device 102 Brushless DC motor 106 Rotor 107 Micro Computer 108 DC power supply 109 DC voltage changing means 110 Drive signal generating means 111 Drive means 112 Switching means

Claims (11)

The time interval is measured for each of the position detection signals generated from the rotor having the N-pole and S-pole magnets alternately applied to the surface, a plurality of position detection elements mounted on the electric circuit board, and the position detection elements. Rotation speed for detecting the number of revolutions, comprising time interval measuring means for storing and time interval averaging means for storing and averaging the time intervals obtained from the time interval measurement means for a period of one rotation at the mechanical angle of the brushless DC motor Detection means, DC voltage changing means for changing the DC voltage applied to the stator winding and changing the number of revolutions, and switching means for sequentially energizing the DC voltage connected to the DC power source and the plurality of stator windings And a signal for changing the DC voltage applied to the stator winding according to the difference in the rotational speed by comparing the predetermined target rotational speed and the rotational speed detected by the rotational speed detecting means to the DC voltage changing means. Output Rotational speed feedback means for controlling to match the target rotational speed is provided, the time interval of one rotation period is measured at the mechanical angle of the brushless DC motor, and the rotational speed is an average value of the time interval of one rotation period. A brushless DC motor control device characterized in that The rotation speed detection means obtains an average value of time intervals of one rotation period for each position detection signal generated from a plurality of position detection elements, detects the rotation speed based on the average value of the time intervals, and the rotation speed feedback means Output judging means for changing the rotational speed output from the rotational speed detecting means and the DC voltage applied to the stator winding is provided, and the output judging means changes the DC voltage applied to the stator winding for each position detection signal. The brushless DC motor control device according to claim 1. The rotation speed detection means obtains an average value of time intervals of one rotation period for each position detection signal generated from a plurality of position detection elements, detects the rotation speed based on the average value of the time intervals, and the rotation speed feedback means Output judging means for changing the DC voltage applied to the stator winding based on the rotation speed output from the rotation speed detecting means and the cycle for changing the DC voltage applied to the stator winding determined in advance for each target rotation speed. The output judging means judges whether or not it is a cycle for changing the DC voltage applied to the stator winding for each position detection signal, and if the cycle is to be changed, the DC voltage is changed, and the cycle must be changed. 2. The brushless DC motor control device according to claim 1, wherein the DC voltage is not changed. The rotation speed feedback means provides a first threshold value and a second threshold value lower than the first threshold value at a rotation speed lower than the target rotation speed. When the rotational speed is lower than the threshold, select the rotational speed obtained from the time interval measuring means, and when the rotational speed is higher than the first threshold, select the rotational speed obtained from the time interval averaging means, When the rotational speed is decreasing, the rotational speed obtained from the time interval averaging means is selected when the rotational speed is higher than the second threshold value, and when the rotational speed is lower than the second threshold value, the rotational speed is lower than the second threshold value. Rotation speed selection means for selecting the rotation speed obtained from the time interval measurement means, and change of the DC voltage applied to the stator when the time interval measurement means is selected and when the time interval average means is selected Gain changing means to change the ratio of In addition, when the rotational speed is low relative to the target rotational speed and the rotational speed difference is large, and when the rotational speed difference is close to the target rotational speed, the rotational speed detection method and the direct current applied to the stator 4. The brushless DC motor control device according to claim 2, wherein a rate of voltage change is switched. The rotational speed feedback means provides a first threshold value and a second threshold value higher than the first threshold value for the rotational speed higher than the target rotational speed. When the rotational speed is higher than the threshold, select the rotational speed obtained from the time interval measuring means, and when the rotational speed is lower than the first threshold, select the rotational speed obtained from the time interval averaging means, When the rotational speed is increasing, the rotational speed obtained from the time interval averaging means is selected when the rotational speed is lower than the second threshold, and when the rotational speed is higher than the second threshold, Rotation speed selection means for selecting the rotation speed obtained from the time interval measurement means, and change of the DC voltage applied to the stator when the time interval measurement means is selected and when the time interval average means is selected Gain changing means to change the ratio of When the rotational speed is higher than the target rotational speed and the difference in rotational speed is large, and when the rotational speed difference is close to the target rotational speed, the rotational speed detection method and the direct current applied to the stator 4. The brushless DC motor control device according to claim 2, wherein the voltage change ratio is switched. There are a plurality of predetermined target rotational speeds, and the target rotational speeds are made to coincide with the target rotational speeds by the rotational speed feedback means for a predetermined time in order of increasing rotational speeds until the required target rotational speeds are reached, and the target rotational speeds are sequentially increased A rotation speed sequential increase means for allowing the rotation speed to reach a required target rotation speed is provided, and the rotation speed increase means increases the rotation sequentially when starting up or when the rotation speed is increased. The brushless DC motor control device according to claim 4. A plurality of predetermined target rotational speeds are provided, and the target rotational speeds are made to coincide with the target rotational speeds by the rotational speed feedback means for a predetermined time in order of increasing rotational speeds until reaching the required target rotational speeds, and the target rotational speeds are sequentially decreased. A rotation speed sequential lowering means is provided to reach a required target rotation speed, and when the engine is stopped or the rotation speed is decreased, the rotation speed is decreased by the rotation speed lowering means. Item 6. The brushless DC motor control device according to Item 5. The rotation speed sequential increase means controls to increase the target rotation time by specifying a time to reach the target rotation time by controlling from a low target rotation speed to a higher target rotation speed every predetermined time. There is a rising arrival time setting means that sets the time of each target rotation speed based on the number of times the target rotation speed is changed and the arrival time, and the target rotation speed is increased by the set arrival time in order. The brushless DC motor control device according to claim 6, wherein: The rotational speed sequential lowering means controls the lower target rotational speed from a high target rotational speed to a lower target rotational speed every predetermined time. There is a descent arrival time setting means that sets the time of each target rotation speed based on the number of times the target rotation speed is changed and the arrival time, and the target rotation speed is reduced by the set arrival time in order. The brushless DC motor control device according to claim 7, wherein: The brushless DC motor control device according to any one of claims 1 to 9, wherein the time interval measuring means has a high time measurement accuracy of 0.1% or less. A transport device equipped with the brushless DC motor control device according to claim 1.

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