JP3814627B2 - AC power source direct-coupled brushless DC motor and electrical equipment equipped with the same - Google Patents

Description

  The present invention mainly includes a ventilation device for exhaust and supply of air such as a pipe fan and a ceiling-embedded type, a brushless DC motor for driving a fan of a blower, a humidifier, a dehumidifier, a refrigeration device, and the brushless DC motor thereof. It relates to the electrical equipment installed.

  In recent years, there has been a strong demand for low-price, high-efficiency, and low-noise performance in fan-driven motors mounted on electrical equipment such as ventilators, and it is difficult to achieve significant increases in efficiency with induction motors. The number of brushless DC motors using permanent magnets is increasing. On the other hand, there is also a demand for an electric motor that is easy to use, such as simply rotating by connecting to an AC power source.

  Conventionally, the thing of the structure disclosed by patent documents 1-3 is known for this kind of electric motor.

  Hereinafter, the electric motor will be described with reference to FIGS.

As shown in the figure, a rectifier 51 that rectifies commercial AC power on a single printed circuit board 56, two-phase drive coils 53 and 54 of a DC motor, and a magnet rotor 55 provided with permanent magnets 55a, Between the motor drive coils 53 and 54 and the rectifying unit 51, a large-capacity electrolytic capacitor is arranged as a smoothing capacitor 59, and switching elements 57 and 58 that allow current to flow in the motor drive coils 53 and 54 only in one direction, and this switching Including the elements 57 and 58, and a control unit 52 that controls energization of the motor drive coils 53 and 54, and directly supplies the high-voltage DC power source rectified by the rectification unit 51 to the motor drive coils 53 and 54. The high-voltage DC power source rectified by the rectifying unit 51 is decompressed and supplied to the control unit 52.
JP 2000-41370 A JP 2000-41395 A Japanese Patent Laid-Open No. 2002-10609

  According to such a conventional electric motor, since it is a two-phase half-wave drive system, in order to prevent the occurrence of dead center, countermeasures can be taken by superimposing spatial harmonic torque, or the interval between stator teeth can be changed. Even if countermeasures are taken, there is a problem that the torque ripple and torque change rate will increase, so noise and vibration will increase and noise reduction will not be possible, and the torque ripple and torque change rate will be reduced to reduce noise and vibration. Is required to do.

  In addition, since it is a half-wave drive system, the current increases and the current change with respect to the load torque also increases, so there is a problem that the range of usable load torque is narrowed, and the current can be reduced and usable. A wide range of load torque is required.

  In addition, since it is a half-wave drive system, copper loss becomes extremely large in high output areas, and there is a problem that the effect of reducing power consumption for induction motors is lost. Even so, it is required to realize low power consumption.

In addition, since the high-voltage DC voltage obtained by the rectifier is directly used as the drive power supply, it is necessary to increase the capacity of the smoothing capacitor after the rectifier, which requires the use of an electrolytic capacitor. There was a problem that the stability of quality could not be secured and the life could not be extended. When the smoothing capacitor has a small capacity, the power supply ripple increases, resulting in an extremely large torque ripple, further vibration and noise, and excessive rotation unevenness. However, there is a problem that the air flow varies and a stable air flow cannot be secured, and it is required that a stable air flow can be secured after realizing miniaturization, high quality and long life of the circuit.

  The present invention solves such a conventional problem, can reduce torque ripple and torque change rate, suppress the generation of noise and vibration, reduce current, and can be used. A brushless DC motor with a direct connection to an AC power source that has a wide torque range, can achieve low power consumption even in a high output range, and can reduce the size of the circuit, improve quality, and prolong its service life, while also suppressing the occurrence of uneven rotation. The purpose is to provide.

  In addition, since the speed cannot be adjusted, it is only possible to support either the forced ventilation mode or the constant ventilation mode with a small air volume in the ventilator. It is required to be able to adjust.

  The present invention solves such a conventional problem, and an object of the present invention is to provide a brushless DC motor directly connected to an AC power source capable of speed adjustment in two or more stages.

  Furthermore, equipment with a built-in centrifugal fan such as a sirocco fan such as a duct type ventilation device is equipped with an induction motor and used in a region where the rotational speed change from the starting torque to the maximum torque is large in its torque characteristics. Most of the devices are installed, and when a brushless DC motor is mounted on such a blower and operated at a constant applied voltage, as shown in the torque-rotational speed characteristic comparison graph of FIG. Since the difference between the rotational speed and the rotational speed at zero static pressure is extremely small compared to the induction motor, the maximum static pressure value in the airflow-static pressure characteristics is equivalent to the value when the induction motor is installed. In this case, there is a problem that the air volume at zero static pressure becomes extremely large, noise and vibration increase, and the effect of reducing power consumption including cooling and heating energy loss is reduced. If the airflow is equal, the maximum static pressure value becomes extremely low, and there is a problem that the airflow fluctuates greatly due to changes in external pressure loss due to outside wind, etc., which is the same as when an induction motor is installed It is required that the air volume-static pressure characteristics of the above can be obtained.

  The present invention solves such a conventional problem, and an object thereof is to provide an AC power supply directly connected brushless DC motor capable of obtaining an air volume-static pressure characteristic equivalent to that when an induction motor is mounted. It is said.

In order to achieve the above object, the brushless DC motor of the present invention is a brushless DC motor directly connected to an AC power supply having the same voltage value, and is insulated from a plurality of AC power supply connecting means connected to the AC power supply and a stator core. A stator having a drive coil wound through a body, a magnet rotor having a permanent magnet, a magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, and a rectifying means for full-wave rectifying the AC power supply And a low voltage DC voltage converting means for converting the high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage, and the low voltage DC voltage generated by the low voltage DC voltage converting means based on the signal of the magnetic pole position detecting means. A drive logic control means for sequentially energizing the drive coil with a full wave in a predetermined direction and order, and a multiplicity for energizing the drive coil based on the output of the drive logic control means. And a switching element, depending on the connection into the AC power source connecting means, the low DC voltage value changing means for changing the value of the low DC voltage generated by the low DC voltage converting means is provided, modified low DC A voltage is supplied to the switching element to change a torque-rotational speed characteristic, thereby forming a configuration of an AC power supply direct-coupled brushless DC motor.

  Since low voltage DC voltage is supplied to the drive coil by this means, the capacity of the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit can be kept low, so that no electrolytic capacitor is required and the circuit is greatly reduced in size. The low voltage DC voltage value changing means for changing the value of the low voltage DC voltage generated by the low voltage DC voltage converting means according to the connection location to the AC power supply connecting means can be provided by switching an external switch, etc. Since the value of the DC voltage can be changed by the number of AC power supply connection means, the brushless DC motor and the electric equipment directly connected to the AC power supply, which can improve the quality, extend the service life, suppress the occurrence of uneven rotation, and adjust the speed of multiple stages. Is obtained.

  Moreover, in order to achieve the above object, the AC power source direct-coupled brushless DC motor of the present invention has a plurality of AC power source connecting means connected to the AC power source, and a fixing coil in which a drive coil is wound around the stator core via an insulator. A magnet rotor having a permanent magnet, a magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectification of the AC power supply, and a high voltage obtained by the rectifying means. Low voltage DC voltage conversion means for converting into a substantially flat low voltage DC voltage, and the low voltage DC voltage generated by the low voltage DC voltage conversion means based on a signal from the magnetic pole position detection means in the drive coil in a predetermined direction and order. Drive logic control means for sequentially conducting full-wave energization at a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and the switching elements A supply current value control means for controlling the supplied average current to be substantially constant, and the supply current value control means for changing the current value controlled substantially constant by the supply current value control means in accordance with the connection location to the AC power supply connection means An AC power supply direct connection type brushless DC motor is provided, which is provided with a current value changing means.

  This means that the torque becomes almost constant, and the difference in rotation speed with respect to load changes increases.Therefore, even if it is installed in a centrifugal fan such as a sirocco fan, the difference in rotation speed between the maximum static pressure and zero rotation is zero. Since it is equivalent to the case where an induction motor is installed, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being extremely increased, and to change the current value supplied to the switching element. From the above, it is possible to perform a substantially constant operation of the torque by the number of AC power supply connection means, and when installed in a centrifugal blower such as a sirocco fan, the same air volume-static pressure characteristics as when an induction motor is installed can be set in multiple stages, A brushless DC motor and an electric device directly connected to an AC power source that can achieve low noise and low power consumption can be obtained.

  Moreover, in order to achieve the above object, the AC power source direct-coupled brushless DC motor of the present invention has a plurality of AC power source connecting means connected to the AC power source, and a fixing coil in which a drive coil is wound around the stator core via an insulator. A magnet rotor having a permanent magnet, a magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectification of the AC power supply, and a high voltage obtained by the rectifying means. Low voltage DC voltage conversion means for converting into a substantially flat low voltage DC voltage, and the low voltage DC voltage generated by the low voltage DC voltage conversion means based on a signal from the magnetic pole position detection means in the drive coil in a predetermined direction and order. Drive logic control means for sequentially conducting full-wave energization at a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and the switching elements Supply power control means for controlling the average power to be supplied to be substantially constant, and supply power change means for changing the power to be controlled to be substantially constant by the supply power control means according to the connection location to the AC power supply connection means It is set as the structure of the AC power supply direct connection type brushless DC motor characterized by providing.

This means that as the load becomes lighter, the current decreases and the applied voltage increases, so the rotational speed difference with respect to the load change increases, and even if mounted on a centrifugal blower such as a sirocco fan, the maximum The difference in rotational speed between static pressure and zero static pressure is the same as when an induction motor is installed, so the maximum static pressure is extremely low and the air volume at zero static pressure is extremely large. Since the power value supplied to the switching element can be changed, operation with a large difference in rotational speed with respect to load fluctuations can be performed by the number of AC power supply connection means. When mounted on a centrifugal blower such as a sirocco fan, induction Brushless D with direct connection to AC power source that can set multiple levels of airflow-static pressure characteristics similar to those equipped with an electric motor, and can achieve low noise and low power consumption Motor and electric equipment can be obtained.

  Moreover, in order to achieve the above object, the AC power source direct-coupled brushless DC motor of the present invention has a plurality of AC power source connecting means connected to the AC power source, and a fixing coil in which a drive coil is wound around the stator core via an insulator. A magnetic rotor provided with a permanent magnet, a magnetic flux density distribution detecting means for detecting a magnetic flux density distribution of the magnet rotor, a rectifying means for full-wave rectification of the AC power supply, and a high voltage obtained by the rectifying means Based on the signal from the low-voltage DC voltage conversion means for converting the voltage into a substantially flat low-voltage DC voltage and the magnetic flux density distribution detection means, the low-voltage DC voltage generated by the low-voltage DC voltage conversion means is applied to the drive coil in a predetermined manner. Drive logic control means for energizing all the waves sequentially in the direction and order, a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and the magnetic flux The magnetic flux density distribution detecting means is arranged so that the magnetic flux density distribution waveform detected by the degree distribution detecting means is substantially similar to the induced voltage waveform induced in the drive coil by the rotation of the magnet rotor. The drive logic control means supplies a current waveform control means for supplying a current substantially similar to the waveform detected by the magnetic flux density distribution detection means to the drive coil, and a supply for controlling the average power supplied to the switching element to be substantially constant. AC power supply direct connection, characterized in that it comprises power control means, and provided with power supply change means for changing the power controlled by the power supply control means to be substantially constant according to the connection location to the AC power supply connection means This is a configuration of a type brushless DC motor.

  By this means, the induced voltage waveform and the current waveform are substantially similar, so the torque ripple and torque change rate are reduced, noise and vibration are suppressed, and the efficiency of the brushless DC motor is greatly improved. The range of load torque that can be used is widened, and the copper loss can be reduced, whereby a brushless DC motor and an electric device directly connected to an AC power source that can realize low power consumption can be obtained. In addition, since the low-voltage DC voltage is supplied to the drive coil, the capacity of the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit can be kept low, so that no electrolytic capacitor is required and the circuit can be significantly reduced in size. In addition, a brushless DC motor and an electric device directly connected to an AC power source that can improve quality, extend the life, and suppress the occurrence of rotation unevenness can be obtained. Furthermore, as the load becomes lighter, the current decreases and the applied voltage increases, so the rotational speed difference with respect to the load change increases, and even when mounted on a centrifugal blower such as a sirocco fan, the maximum The difference in rotational speed between static pressure and zero static pressure is the same as when an induction motor is installed, so the maximum static pressure is extremely low and the air volume at zero static pressure is extremely large. Since the power value supplied to the switching element can be changed, operation with a large difference in rotational speed with respect to load fluctuations can be performed by the number of AC power supply connection means. When mounted on a centrifugal blower such as a sirocco fan, induction A brushless DC module directly connected to an AC power source that can be set in multiple stages with the same airflow-static pressure characteristics as when an electric motor is installed, and can achieve low noise and low power consumption. Data and electrical equipment can be obtained.

  Further, in order to achieve the above object, the AC power source directly connected brushless DC motor of the present invention is provided with magnetic flux density distribution waveform synthesizing means for synthesizing two phases of waveforms detected by the magnetic flux density distribution detecting means. The logic control means has a configuration of an AC power supply direct connection type brushless DC motor in which a current substantially similar to the waveform synthesized by the magnetic flux density distribution waveform synthesizing means is supplied to the drive coil.

  This means that harmonic components such as third and fifth harmonics in the current waveform can be removed. Therefore, the AC power supply direct connection type that can reduce noise and vibration while suppressing the inclusion of harmonic components in the instantaneous torque. Thus, a brushless DC motor and an electric device can be obtained.

In order to achieve the above object, the AC power source directly connected brushless DC motor of the present invention has a configuration of an AC power source directly connected brushless DC motor characterized in that the permanent magnet of the magnet rotor is a polar anisotropic magnet. It is a thing.

  This means that the induced voltage waveform becomes a substantially sine wave, so the torque ripple and torque change rate are further reduced, and the generation of noise and vibration is further suppressed. Thus, a brushless DC motor and an electric device can be obtained.

  In order to achieve the above object, the AC power source directly connected brushless DC motor according to the present invention forms a current waveform by PWM control of the drive logic control means. It is a configuration.

  Since the heat generation of the switching element can be suppressed by this means, a brushless DC motor directly connected to an AC power source and an electric device that can further widen the range of usable load torque can be obtained.

  According to the present invention, since a low-voltage DC voltage is supplied to the drive coil and full-wave energization is performed, the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit is kept low enough to compensate for a very short period of voltage shortage. Therefore, it is possible to reduce the size and space of the capacitor and to use a ceramic capacitor or a film capacitor without using an electrolytic capacitor. High quality, long lifespan, torque ripple and rotation unevenness can be suppressed, current can be reduced, the range of usable load torque is wide, and low power consumption can be realized even in the high output range. The voltage of the low-voltage DC voltage is the same as the number of AC power supply connection means by switching external switches. Because it can further be provided a brushless DC motor and electrical equipment of the AC power source directly coupled capable of speed adjustment of the plurality of stages.

  In addition, according to the present invention, the average current value flowing through the switching element is detected by the current detection means, and the average current supplied to the switching element by the supply current value control means is controlled to be substantially constant, so that the output torque is substantially constant. Therefore, in the electrical equipment such as a ventilator equipped with a centrifugal blower such as a sirocco fan, the difference in rotational speed between the maximum static pressure and the zero static pressure is induced. Since it is equivalent to the case where an electric motor is installed, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being excessively increased, to reduce noise and to reduce power consumption. Since the current value supplied to the element can be changed, the torque can be operated almost as many times as the number of AC power supply connection means, and it can be installed in a centrifugal blower such as a sirocco fan. Sometimes, the air volume of the same as the case of mounting the induction motor - with static pressure characteristics may be multiple levels set, noise reduction, can provide a brushless DC motor and electrical equipment of the AC power source directly coupled to reduction in power consumption can be realized.

  In addition, according to the present invention, the supply current decreases as the load on the motor becomes lighter, so the applied voltage is increased accordingly, and conversely the supply current increases as the load becomes heavier. Since the applied voltage is lowered, the rotational speed difference with respect to the load change becomes large. Even when mounted on a centrifugal blower such as a sirocco fan, the rotational speed difference at the maximum static pressure and the rotational speed at zero static pressure are induced. Since it is the same as when an electric motor is installed, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being extremely increased, and there is no change in power consumption due to load fluctuations. , Noise reduction and low power consumption can be realized. Furthermore, since the power value supplied to the switching element can be changed, operation with a large rotational speed difference with respect to load fluctuations can be performed by the number of AC power supply connection means. When mounted on a centrifugal blower such as a sirocco fan, an induction motor is installed. It is possible to provide an AC power supply directly connected brushless DC motor and an electric device that can set a plurality of air flow-static pressure characteristics similar to those in the case of mounting.

  In addition, according to the present invention, the induced voltage waveform and the current waveform are substantially similar, so the torque ripple and torque change rate are reduced, noise and vibration are suppressed, and the efficiency of the brushless DC motor is greatly increased. Since the range of usable load torque is widened and copper loss can be reduced, low power consumption can be realized, low voltage DC voltage is supplied to the drive coil, and full-wave energization is performed. Since the capacity of the smoothing capacitor used in the subsequent stage of the wave rectifier circuit can be kept low, long life can be achieved without using an aluminum electrolytic capacitor containing an electrolytic solution that has a high equivalent series resistance and changes in characteristics depending on the operating ambient temperature. Polymer capacitors and film capacitors, which are solid capacitors with low equivalent series resistance and very little change in characteristics due to the ambient temperature. It is possible to handle even a capacitor or ceramic capacitor, and the circuit can be significantly reduced in size, quality, and service life. In addition, the load on the motor is not affected by voltage fluctuations or frequency changes of the AC power supply. As the load becomes lighter, the supply current becomes lower. Therefore, the applied voltage is increased accordingly. Conversely, if the load becomes heavier, the supply current becomes higher. The difference will become large, and even if it is installed in a centrifugal blower such as a sirocco fan, the difference in rotation speed at maximum static pressure and rotation speed at zero static pressure will be the same as when an induction motor is installed. It is possible to prevent the static pressure from becoming extremely low and the air volume at zero static pressure from being extremely increased, and there is no change in power consumption with respect to load fluctuations. Since the power value can be changed, operation with a large difference in rotational speed against load fluctuations can be performed by the number of AC power supply connection means. When installed in a centrifugal blower such as a sirocco fan, the same air volume as when an induction motor is installed -It is possible to provide a brushless DC motor and an electric device directly connected to an AC power source, in which static pressure characteristics can be set in a plurality of stages, and noise reduction and low power consumption can be realized.

  In addition, according to the present invention, the influence of variations in the magnetic flux density distribution detecting means of each phase is reduced, and the magnetic flux density distribution waveform of each phase is basically a waveform whose phase is simply shifted. By subtracting and synthesizing the two phases, the harmonic component contained in the detected magnetic flux density distribution waveform is removed, so that the occurrence of rotation unevenness can be suppressed and the torque ripple and torque change rate can be further reduced. Therefore, it is possible to provide a brushless DC motor and an electric device directly connected to an AC power source that achieve high quality.

  Further, according to the present invention, since the induced voltage waveform is a sine wave, the torque ripple and the torque change rate can be further reduced, and the motor efficiency is greatly improved. A brushless DC motor and an electric device directly connected to an AC power source that realizes the above can be provided.

  Further, according to the present invention, since the heat generation of the switching element can be suppressed, it is possible to provide an AC power supply directly connected brushless DC motor and an electric device that can further expand the range of usable load torque.

The invention according to claim 1 of the present invention is a brushless DC motor that is directly connected to an AC power source having the same voltage value, and a plurality of AC power source connecting means for connecting to the AC power source, and a stator core via an insulator. A stator around which a drive coil is wound, a magnet rotor having a permanent magnet, a magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectification of the AC power supply, and the rectification Based on the signal from the magnetic pole position detection means, the low voltage DC voltage generated by the low voltage DC voltage conversion means is driven based on the signal from the magnetic pole position detection means. Drive logic control means for sequentially energizing the coil in a predetermined direction and in order, and a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means. , Depending on the connection into the AC power source connecting means, said providing a low DC voltage value changing means for changing the value of the low DC voltage generated by the low-pressure DC voltage converting means, a low pressure DC voltage was changed to the switching element This is a configuration of an AC power supply direct-coupled brushless DC motor characterized in that the torque-rotational speed characteristic is changed , and the smoothing capacitor used in the subsequent stage of the full-wave rectifier circuit is very short that the voltage is insufficient. Capacitance can be kept low enough to compensate for the period. Capacitors can be reduced in size, space-saving, high quality, greatly extended service life, torque ripple and uneven rotation can be suppressed, and current can be reduced and used. The range of possible load torque is wide, low power consumption can be realized even in the high output range, and it is not affected by voltage fluctuations or frequency changes of the AC power supply. Is by switching the external switch has the effect that the value of the low DC voltage can be changed by the number of the AC power source connecting means.

  The invention according to claim 2 is a plurality of AC power supply connection means for connecting to an AC power supply, a stator having a stator core wound with a drive coil via an insulator, and a magnet rotor provided with a permanent magnet. A magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectifying the AC power supply, and a low voltage DC voltage for converting a high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage Drive logic control means for sequentially energizing the drive coil in a predetermined direction and order with the low-voltage DC voltage generated by the low-voltage DC voltage conversion means based on the signal from the conversion means and the magnetic pole position detection means And a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and a supply current value control means for controlling the average current supplied to the switching elements to be substantially constant. AC power supply direct connection, characterized in that supply current value change means for changing a current value controlled substantially constant by the supply current value control means according to the connection location to the AC power supply connection means is provided. The type of brushless DC motor is configured to detect the average current value flowing through the switching element by the current detection means, and the supply current value control means controls the average current supplied to the switching element to be substantially constant. The operation is such that the output torque is substantially constant and the difference in rotational speed with respect to the load change is increased. Furthermore, it has the effect | action that a torque substantially constant operation | movement can be performed by the number of AC power supply connection means.

  The invention according to claim 3 is a plurality of AC power source connection means for connecting to an AC power source, a stator in which a drive coil is wound around a stator core via an insulator, and a magnet rotor including a permanent magnet. A magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectifying the AC power supply, and a low voltage DC voltage for converting a high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage Drive logic control means for sequentially energizing the drive coil in a predetermined direction and order with the low-voltage DC voltage generated by the low-voltage DC voltage conversion means based on the signal from the conversion means and the magnetic pole position detection means And a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and a supply power control means for controlling the average power supplied to the switching elements to be substantially constant And an AC power supply direct connection type brushless DC motor provided with a supply power changing means for changing the power controlled by the supply power control means to be substantially constant according to the connection location to the AC power supply connection means Since the supply current decreases as the load applied to the motor becomes lighter, the applied voltage is increased accordingly, and conversely the supply current increases as the load becomes heavier. In order to reduce the applied voltage, there is an effect that the rotational speed difference with respect to the load change is increased. Furthermore, since the electric power value supplied to the switching element can be changed, there is an effect that an operation with a large rotational speed difference with respect to the load fluctuation can be obtained by the number of AC power supply connecting means.

According to a fourth aspect of the present invention, there are provided a plurality of AC power source connecting means for connecting to an AC power source, a stator in which a drive coil is wound around a stator core via an insulator, and a magnet rotor including a permanent magnet. A magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor, a rectifying means for full-wave rectifying the AC power supply, and a low voltage for converting a high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage. Based on the signals from the DC voltage conversion means and the magnetic flux density distribution detection means, a drive for sequentially energizing the drive coil with the low voltage DC voltage generated by the low voltage DC voltage conversion means in a predetermined direction and in order. Based on the logic control means, a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and a magnetic flux density distribution waveform detected by the magnetic flux density distribution detection means The magnetic flux density distribution detecting means is arranged so as to be substantially similar to the induced voltage waveform induced in the driving coil by the rotation of the magnet rotor, and the driving logic control means includes the magnetic flux density distribution detecting means. Current waveform control means for supplying a current substantially similar to the detected waveform to the drive coil, and supply power control means for controlling the average power supplied to the switching element to be substantially constant, to the AC power supply connection means According to the present invention, there is provided a configuration of an AC power supply direct-coupled brushless DC motor, characterized in that supply power changing means for changing the power controlled by the supplied power control means to be substantially constant is provided according to the connection location. Since the waveform and current waveform are almost similar, the torque ripple and torque change rate are reduced, and the smoothing circuit used in the subsequent stage of the full-wave rectifier circuit is reduced. Densers can keep the capacity low enough to compensate for a very short period of voltage shortage, reduce torque ripple, increase efficiency, prevent rotation irregularities, and even if the voltage and frequency of the AC power supply change There is an effect that there is no change in the output characteristics and an operation with a large rotational speed difference with respect to the load fluctuation can be obtained by the number of AC power supply connecting means.

  According to a fifth aspect of the present invention, there is provided magnetic flux density distribution waveform synthesizing means for synthesizing two phases of the waveforms detected by the magnetic flux density distribution detecting means, and the drive logic control means is provided by the magnetic flux density distribution waveform synthesizing means. This is a configuration of an AC power supply direct connection type brushless DC motor in which a current substantially similar to the synthesized waveform is passed through the drive coil, and harmonic components such as third harmonic and fifth harmonic in the current waveform can be removed. It has the action.

  According to the sixth aspect of the present invention, the permanent magnet of the magnet rotor is a polar anisotropic magnet, and the AC power source directly connected brushless DC motor is configured. The induced voltage waveform is substantially sinusoidal. Therefore, the torque ripple and the torque change rate are further reduced.

  According to a seventh aspect of the present invention, there is provided a configuration of an AC power supply direct-coupled brushless DC motor, wherein the drive logic control means forms a current waveform by PWM control, and the switching element generates heat. It has the effect that it can be suppressed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
As shown in FIGS. 1 to 3, reference numeral 1 denotes a brushless DC motor directly connected to an AC power source, and 10 denotes a drive coil 2 via an insulator 11 formed of an insulating material on a stator core 10a having a plurality of slots. In the wound stator, the stator 10 is molded with a thermosetting resin 21 to form a jacket, and 17 is a bracket that holds the bearing 20. Reference numeral 3 denotes a magnet rotor, which is formed by integrally orienting a plastic magnet with the shaft 19 during the injection molding, and the main magnetic pole portion is a polar anisotropic magnet 3a. A hall element 4 serves as a magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the polar anisotropic magnet 3a. The waveform detected by the hall element 4 is induced in the drive coil 2 by the polar anisotropic magnet 3a. The gap between the Hall element 4 and the polar anisotropic magnet 3a is set and arranged so as to be substantially similar to the voltage waveform. A magnetic flux density distribution waveform synthesizing unit 12 subtracts the v-phase waveform from the u-phase waveform of the Hall element 4 in order to remove the harmonic component of the current waveform supplied to the u-phase of the drive coil 2, and similarly the drive coil. For the v phase of 2, the w phase waveform is subtracted from the v phase waveform of the Hall element 4, and for the w phase of the drive coil, the u phase waveform is subtracted from the w phase waveform of the Hall element 4. Reference numeral 5 denotes drive logic control means for controlling ON / OFF of the switching element 6 so that the drive coil 2 is sequentially full-wave energized in a predetermined direction and order. The current waveform control means 7 is controlled by the magnetic flux density distribution waveform synthesis means 12. The output bias current is adjusted while performing feedback so that the switching element 6 is in a non-saturated state close to saturation so that the waveform is substantially similar to the waveform from which the harmonic components are removed. Reference numeral 15 denotes AC power connection means for connecting commercial AC power, 15a is a strong output connection terminal, 15b is a weak output connection terminal, and 15c is a common connection terminal. 9 is a rectifying means for full-wave rectification of the AC power supply, and 8 is a low-voltage DC voltage converting means for converting a high-voltage voltage having ripples full-wave rectified by the rectifying means 9 into a substantially flat low-voltage DC voltage of 45V or less. The low-voltage DC voltage converted by the low-voltage DC voltage conversion means 8 is supplied to the drive coil 2 via the switching element 6 and also supplied as control power to the drive logic control means 5 and the like. Between the low-voltage DC voltage converting means 8 and the rectifying means 9, a small-capacity smoothing capacitor 18 is arranged to compensate for a voltage of 2.1 milliseconds, which is 45V or less when full-wave rectification is performed on AC 100V50Hz. Yes. Reference numeral 22 denotes an external switch which is connected to either the strong output connection terminal 15a or the weak output connection terminal 15b. Reference numeral 14 denotes an AC input photocoupler or the like when an AC power source is connected to the weak output connection terminal 15b. The low-voltage direct-current voltage value generated by the low-voltage direct-current voltage conversion means 8 is set to a voltage lower than that when the alternating-current power supply is connected to the strong output connection terminal 15a. It is a low voltage DC voltage changing means for conversion. 1 except for the smoothing capacitor 18 and the coil which is one of the components constituting the low-voltage DC voltage conversion means 8 among the electronic components surrounded by the one-dot chain line in FIG. The one-chip IC 16 is formed by connection.

  According to the brushless DC motor 1 directly connected to the AC power source of the present invention, the high voltage having ripples rectified by the rectifying means 9 for full-wave rectification is converted into a substantially flat voltage whose low voltage DC voltage converting means 8 is 45 V or less. By converting the voltage into a low-voltage DC voltage and supplying it to the drive coil 2 as a drive power supply, the smoothing capacitor 18 after full-wave rectification is kept low enough to compensate for the very short period of 2.1 milliseconds that the voltage is insufficient. Capacitors can be reduced in size and space, and ceramic capacitors and film capacitors can be used without using electrolytic capacitors, resulting in significant downsizing and no change in temperature characteristics. A brushless DC motor directly connected to an AC power source that can improve quality and extend the life can be obtained.

  Further, even if the capacity of the smoothing capacitor 18 is small, the low-voltage DC voltage conversion means 8 generates a substantially flat low-voltage DC voltage, so that a brushless DC motor directly connected to an AC power source with reduced torque ripple and rotation unevenness can be obtained. And even if it uses for fan drive, stabilization of ventilation volume is realizable.

  In addition, since the driving logic control means 5 performs three-phase full-wave driving, there is no need to consider the dead point, torque ripple and torque change rate can be reduced, driving current can be reduced, and copper in a high output region can be reduced. Since the loss can be reduced, it is possible to obtain a brushless DC motor directly connected to an AC power source that suppresses the generation of noise and vibration, has a wide range of usable load torque, and can realize low power consumption even in a high output region.

  Further, the gap between the magnetic flux density distribution detecting means 4 and the magnet is set so that the waveform detected by the magnetic flux density distribution detecting means 4 is substantially similar to the induced voltage waveform induced in the drive coil 2 by the polar anisotropic magnet 3a. The current waveform control means 7 causes the induced voltage waveform and the current waveform to be substantially similar by passing a current substantially similar to the magnetic flux density distribution waveform detected by the magnetic flux density distribution detection means 4 to the drive coil 2. The torque ripple and the rate of change in torque can be further reduced, and the motor efficiency is greatly improved. Therefore, a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency can be obtained.

  Further, by making the main magnetic pole portion of the magnet rotor 3 the polar anisotropic magnet 3a, both the induced voltage waveform and the current waveform become sinusoidal waves, so that the torque ripple and the torque change rate can be further reduced. In addition, since the motor efficiency is greatly improved, it is possible to obtain a brushless DC motor directly connected to an AC power source that achieves low noise and high efficiency.

Further, the magnetic flux density distribution waveform synthesizing unit 12 synthesizes the u-phase, v-phase, and w-phase waveforms detected by the magnetic flux density distribution detection unit 4, so that the influence of variations in the magnetic flux density distribution detection unit 4 of each phase is affected. As the magnetic flux density distribution waveform of each of the u-phase, v-phase, and w-phase is basically a waveform that is simply shifted in phase, the detected magnetic flux is obtained by subtracting and synthesizing the two phases. Since harmonic components contained in the density distribution waveform are removed, rotation irregularity can be suppressed, and torque ripple and torque change rate can be further reduced. The brushless DC motor is obtained.

  Further, the speed adjustment command voltage detection means 13 is provided, the speed adjustment command voltage detection means 13 detects the presence or absence of the speed command voltage, and the low-voltage DC voltage value changing means 14 receives the presence of the speed command voltage, and the low-voltage DC voltage value changing device 14 By changing the value of the low-voltage DC voltage generated by the means 8, two-stage low-voltage DC voltage output adjustment can be performed, so that an AC power source directly connected brushless DC motor capable of two-stage speed adjustment can be obtained.

  Further, in the AC power source connecting means 15, two low voltage DC voltage output adjustments can be made by providing two positions, such as the strong output connection terminal 15a and the weak output connection terminal 15b, and providing the low voltage DC voltage value changing means 14. Thus, a brushless DC motor directly connected to an AC power source capable of speed adjustment can be obtained. Here, in the AC power supply connecting means 15, if the set amount of the low-voltage DC voltage value changing means 14 is changed according to the number of connecting terminals, the speed can be adjusted by the number of connecting terminals.

  In the first embodiment, the current waveform supplied to the drive coil 2 is configured to be substantially similar to the induced voltage waveform. However, the current waveform supplied to the drive coil 2 has a rectangular shape of 120 degrees depending on the use and the noise level required for the product. Wide-angle energization methods such as wave energization and 140-degree and 150-degree energization are also possible. By supplying a low-voltage DC voltage to the drive coil 2 as a drive power supply, the capacity of the smoothing capacitor after full-wave rectification can be kept low and rotated. Suppressing unevenness and reducing copper loss in the high output area, greatly reducing size, improving quality, extending the service life, and wide range of usable load torque, reducing power consumption even in the high output area There is no difference in obtaining a brushless DC motor directly connected to an AC power supply.

  In the first embodiment, the magnetic flux density distribution detecting means 4 is used. However, a method of determining the energization phase for the magnet rotor by detecting the induced voltage or current induced in the non-energization phase may be used. , No difference in its effects.

  In the first embodiment, the output bias current is adjusted while performing feedback so that the switching element 6 is in a non-saturated state close to saturation. However, the switching element 6 may be PWM-controlled to control the current waveform. In that case, since the loss of the switching element 6 can be reduced, the heat generation of the switching element 6 is suppressed, and a brushless DC motor directly connected to the AC power source that can further widen the range of usable load torque can be obtained.

  In the first embodiment, the low-voltage DC voltage conversion means 8 converts the voltage to a substantially flat low-voltage DC voltage of 45V or less. However, if the voltage is converted to a low-voltage DC voltage of 36V or less, the period of 1.7 milliseconds is compensated. Therefore, it can be further reduced to a capacitor capacity of only 1.

  In the first embodiment, the AC power supply connection means 15 is connected to the speed adjustment instruction voltage detection means 13. However, the rectification means 9 and the smoothing capacitor 18 may be additionally provided, and there is a difference in the operation and effect. Does not occur.

(Embodiment 2)
As shown in FIGS. 4 and 5, reference numeral 25 denotes a ceiling-embedded ventilation fan, which is a type of ventilation device, and a brushless DC motor 27 directly connected to an AC power source is mounted for driving the fan. Reference numeral 23 denotes current detection means for detecting the current supplied to the switching element 6, and reference numeral 24 denotes supply current value control means. The supply current value control means 24 controls the low-voltage DC voltage value changing means 14 so that the average current value supplied to the switching element 6 detected by the current detection means 23 is equal to the set current value. Thus, feedback control is performed while varying the voltage output from the low-voltage DC voltage converting means 8. The supply current value changing means 26 changes the set value of the current that flows through the switching element 6 in accordance with a signal from the speed adjustment command voltage detecting means 13, and the other parts are the same as those in the first embodiment. Are given the same numbers, and detailed description is omitted.

  According to the brushless DC motor 27 directly connected to the AC power source of the present invention as described above, the supply current value control means 24 controls the average current supplied to the switching element 6 so that the output torque is substantially constant, Since the rotational speed difference with respect to the load change becomes large, in the ventilation device 25 equipped with a centrifugal blower such as a sirocco fan, when the induction motor is equipped with a rotational speed difference between the maximum static pressure and the zero static pressure Therefore, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at the time of zero static pressure from being extremely increased, as well as to realize low noise and low power consumption.

  Further, a speed adjustment instruction voltage detection means 13 is provided, the speed adjustment instruction voltage detection means 13 detects the presence or absence of the speed instruction voltage, and the supply current value changing means 26 flows to the switching element 6 in response to the presence of the speed instruction voltage. By changing the set value of the current, it is possible to perform a two-stage torque substantially constant operation. In the ventilator 25 equipped with a centrifugal blower such as a sirocco fan, the same air volume-static pressure as when an induction motor is installed. Since the characteristics can be set in two stages, the ventilation device 25 can support both the forced ventilation mode and the constant ventilation mode.

  Further, in the AC power supply connection means 15, two places of the strong output connection terminal 15a and the weak output connection terminal 15b are provided, and the supply current value changing means 26 is provided, so that a two-stage torque can be operated substantially constant. In the ventilation device 25 equipped with a centrifugal blower such as a fan, the air volume-static pressure characteristics equivalent to those when an induction motor is installed can be set in two stages. Here, in the AC power source connecting means 15, if the set amount of the supply current value changing means 26 is changed according to the number of connecting terminals, the speed can be adjusted by the number of connecting terminals.

  It should be noted that there is no difference in the operational effects in the same configuration as in the first embodiment.

  Further, as shown in FIG. 6, by replacing the supply current value control means 24 with the supply power control means 28 and replacing the supply current value change means 26 with the supply power change means 29, the load on the motor becomes lighter. Since the supply current is reduced, the applied voltage is increased accordingly, and conversely, if the load is heavy, the supply current is increased, so the applied voltage is lowered, so that the difference in rotational speed with respect to the load change is increased. Even if it is installed in a centrifugal blower such as a sirocco fan, the maximum static pressure is extremely high because the difference between the number of rotations at maximum static pressure and the number of rotations at zero static pressure is the same as when an induction motor is installed. It is possible to prevent the air flow from becoming low and the air volume at the time of zero static pressure from becoming extremely large, and there is no change in the power consumption with respect to the load fluctuation, so that it is possible to realize noise reduction and low power consumption.

(Embodiment 3)
As shown in FIG. 7, reference numeral 30 denotes a brushless DC motor directly connected to an AC power source. The rectifier 9, the small-capacity smoothing capacitor 18, the low-voltage DC voltage converter 8, the magnetic flux density distribution detector 4, and the magnetic flux density distribution waveform synthesizer 12. The drive logic control means 5, the switching element 6, and the current waveform control means 7 are mounted on the same printed circuit board and incorporated in the brushless DC motor 30. Reference numeral 31 denotes a low-voltage DC voltage derivation terminal for deriving the low-voltage DC voltage generated by the low-voltage DC voltage conversion means 8 to the outside of the brushless DC motor 30, and the low-voltage power source derived from the low-voltage DC voltage derivation terminal 31 to the outside of the brushless DC motor 30. The pressure is reduced by the pressure reducing means 33 formed by a nearby resistance voltage dividing circuit or the like, and this reduced DC voltage is introduced into the brushless DC motor 30 from the low voltage DC voltage introduction terminal 32, and the switching element 6 and the drive logic control means 5 are introduced. In other configurations, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  According to the brushless DC motor 30 directly connected to the AC power source of the present invention as described above, the low voltage DC voltage deriving terminal 31 for deriving the low voltage DC voltage generated by the low voltage DC voltage converting means 8 to the outside of the brushless DC motor 30, and this A low-voltage DC voltage introduction terminal 32 for introducing a low-voltage DC voltage obtained by reducing the low-voltage DC voltage derived from the low-voltage DC voltage deriving terminal 31 into the brushless DC motor 30 is provided. The low-voltage DC voltage introduced from the low-voltage DC voltage introduction terminal 32 Is provided to the switching element 6 so that a low-pressure DC voltage can be varied steplessly by providing a simple decompression means 33 outside the brushless DC motor. A brushless DC motor 30 directly connected to an AC power source that can be adjusted and the brushless DC motor 30 are mounted. Electrical equipment can be obtained.

(Embodiment 4)
As shown in FIG. 8, reference numeral 34 denotes an AC power source direct connection type brushless DC motor, which includes a rectifier 9, a small-capacity smoothing capacitor 18, a low-voltage DC voltage converter 8, a magnetic flux density distribution detector 4, and a magnetic flux density distribution waveform synthesizer 12. , Driving logic control means 5, switching element 6, current waveform control means 7, low voltage DC voltage changing means 14, current detecting means 23, supply current value control means 24, and supply current value changing means 26 are mounted on the same printed circuit board. In addition, the brushless DC motor 34 is built in. Reference numeral 31 denotes a low-voltage DC voltage deriving terminal for deriving the low-voltage DC voltage generated by the low-voltage DC voltage converting means 8 to the outside of the brushless DC motor 34. The low-voltage power source derived from the low-voltage DC voltage deriving terminal 31 is external to the brushless DC motor 34. The pressure is reduced by a pressure reducing means 33 formed by a nearby resistance voltage dividing circuit or the like, and converted into a supply current value indicating voltage. This supply current value indicating voltage is supplied from the supply current set value input means 35 to the brushless DC motor 34. The configuration is such that the supply current value changing means 26 changes the average current value controlled substantially constant by the supply current value control means 24 in accordance with the magnitude of the supply current value indicating voltage. Other Embodiment 1 The same parts as those of 2 and 2 are designated by the same reference numerals, and detailed description thereof is omitted.

  According to the brushless DC motor 34 directly connected to the AC power source of the present invention as described above, the low voltage DC voltage deriving terminal 31 for deriving the low voltage DC voltage generated by the low voltage DC voltage converting means 8 to the outside of the brushless DC motor 34, and this Supply current set value input means 35 for introducing a low voltage DC voltage obtained by reducing the low voltage DC voltage derived from the low voltage DC voltage deriving terminal 31 into the brushless DC motor 34 is provided, and the low voltage introduced from the supply current set value input means 35 is provided. The supply current value changing means 26 changes the average current value controlled by the supply current value control means 24 in accordance with the magnitude of the DC voltage so that the pressure reducing means 33 can be simply reduced outside the brushless DC motor 34. As a result, it will be possible to operate with almost constant torque steplessly, and will be installed in centrifugal blowers such as sirocco fans. And when the wind amount similarly to the case of mounting the induction motor - static pressure characteristic is electrical equipment equipped with an AC power supply direct connection type brushless DC motor 34 and its brushless DC motor 34 that can be set steplessly can be obtained.

  In the fourth embodiment, the low-voltage direct-current voltage generated by the low-voltage direct-current voltage conversion means 8 is derived outside the brushless DC motor 34, and a voltage serving as a set value signal for the average current value supplied by reducing the pressure is generated and supplied. Although it is input to the current set value input means 35, it may be input from another power source, and there is no difference in the effect that a substantially constant current operation can be performed in a stepless manner.

In the fourth embodiment, the supply current value control means 24 and the supply current value change means 26 are configured to perform an operation with a substantially constant average current. However, as shown in FIG. As the load applied to the motor becomes lighter by replacing the control means 28, replacing the supply current value changing means 26 with the supply power changing means 29, and replacing the supply current set value input means 35 with the supply power set value input means 36. The supply current is reduced and the applied voltage is increased accordingly. Conversely, if the load is heavy, the supply current is increased, so the applied voltage is lowered, so that the difference in rotational speed with respect to the load change is increased. Even when mounted on a centrifugal blower such as a sirocco fan, the difference in rotational speed between maximum static pressure and zero static pressure is the same as when an induction motor is installed. Therefore, it is possible to prevent the maximum static pressure from becoming extremely low and the air volume at zero static pressure from being excessively increased, and there is no change in power consumption due to load fluctuations, resulting in quietness and low power consumption. Since this can be realized, an AC power supply directly connected brushless DC motor capable of setting the same air volume-static pressure characteristics as in the case where an induction motor is installed and an electric device equipped with the brushless DC motor can be obtained.

  As described above, the brushless DC motor directly connected to an AC power source according to the present invention can obtain the same characteristics as an induction motor in which the rotational speed change with respect to the load is large in the rotational speed-torque characteristics. It is useful to install in air conditioners such as ventilators, water heaters, and air conditioners, air purifiers, dehumidifiers, dryers, and fan filter units.

The block diagram which shows the alternating current power supply direct connection type brushless DC motor in Embodiment 1 of this invention Sectional view showing the brushless DC motor The figure which shows the voltage waveform after the rectification of the brushless DC motor The block diagram which shows the alternating current power supply direct connection type brushless DC motor in Embodiment 2 of this invention Sectional view showing a ventilator equipped with the brushless DC motor Block diagram showing another configuration of the brushless DC motor The block diagram which shows the alternating current power supply direct connection type brushless DC motor in Embodiment 3 of this invention The block diagram which shows the alternating current power supply direct connection type brushless DC motor in Embodiment 4 of this invention Block diagram showing another configuration of the brushless DC motor Circuit diagram showing a conventional DC motor Sectional view showing the DC motor Perspective view showing the DC motor Graph comparing torque-rotational speed characteristics of DC motor and induction motor

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Brushless DC motor 2 Drive coil 3 Magnet rotor 4 Magnetic flux density distribution detection means 5 Drive logic control means 6 Switching element 7 Current waveform control means 8 Low voltage direct current voltage conversion means 9 Rectification means 10 Stator 10a Stator core 11 Insulator 12 Magnetic flux Density distribution waveform synthesis means 13 Speed adjustment instruction voltage detection means 14 Low voltage DC voltage change means 15 AC power supply connection means 15a Strong output connection terminal 15b Weak output connection terminal 15c Common connection connection terminal 16 One-chip IC
DESCRIPTION OF SYMBOLS 17 Bracket 18 Smoothing capacitor 19 Shaft 20 Bearing 21 Thermosetting resin 22 External switch 23 Current detection means 24 Supply current value control means 25 Ventilator 26 Supply current value change means 27 Brushless DC motor 28 Supply power control means 29 Supply power change means 29 DESCRIPTION OF SYMBOLS 30 Brushless DC motor 31 Low voltage | pressure DC voltage derivation | leading-out terminal 32 Low voltage | pressure DC voltage introduction | transduction terminal 33 Pressure reduction means 34 Brushless DC motor 35 Supply current setting value input means 36 Supply power setting value input means

Claims (9)

A brushless DC motor directly connected to an AC power supply having the same voltage value, a plurality of AC power connection means connected to the AC power supply, a stator having a stator core wound with a drive coil via an insulator, and a permanent A magnet rotor having a magnet, a magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, a rectifying means for full-wave rectifying the AC power supply, and a high voltage obtained by the rectifying means is a substantially flat low voltage Based on the signal from the low-voltage DC voltage conversion means for converting to DC voltage and the magnetic pole position detection means, the low-voltage DC voltage generated by the low-voltage DC voltage conversion means is sequentially applied to the drive coil in a predetermined direction and in order. a drive logic control means for energizing, based on the output of the drive logic control means, and a plurality of switching elements for energization of the drive coil, contact to the AC power source connecting means Depending on the location, the provided low DC voltage value changing means for changing the value of the low DC voltage generated by the low-pressure DC voltage converting means, by supplying a low DC voltage is changed to the switching element, the torque - rotational speed characteristic The AC power supply direct connection type brushless DC motor characterized by changing .
  A brushless DC motor directly connected to an AC power source, comprising a plurality of AC power source connecting means for connecting to the AC power source, a stator having a stator core wound with a drive coil via an insulator, and a permanent magnet Magnet rotor, magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, rectifying means for full-wave rectifying the AC power supply, and converting the high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage The low-voltage DC voltage conversion means that performs the full-wave energization sequentially in a predetermined direction and order to the drive coil based on the signals of the low-voltage DC voltage conversion means and the magnetic pole position detection means. The drive logic control means, a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and an average current supplied to the switching elements are substantially equal to each other. And supply current value control means for changing the current value controlled substantially constant by the supply current value control means according to the connection location to the AC power supply connection means. AC brushless DC motor directly connected to AC power source.   A brushless DC motor directly connected to an AC power source, comprising a plurality of AC power source connecting means for connecting to the AC power source, a stator having a stator core wound with a drive coil via an insulator, and a permanent magnet Magnet rotor, magnetic pole position detecting means for detecting the magnetic pole position of the magnet rotor, rectifying means for full-wave rectifying the AC power supply, and converting the high voltage obtained by the rectifying means into a substantially flat low voltage DC voltage The low-voltage DC voltage conversion means that performs the full-wave energization sequentially in a predetermined direction and order to the drive coil based on the signals of the low-voltage DC voltage conversion means and the magnetic pole position detection means. Based on the drive logic control means, a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and the average power supplied to the switching elements is approximately one. Supply power control means for controlling the power supply, and supply power change means for changing the power controlled by the supply power control means to be substantially constant according to the connection location to the AC power supply connection means. Brushless DC motor with direct connection to AC power supply. A brushless DC motor directly connected to an AC power source, comprising a plurality of AC power source connecting means for connecting to the AC power source, a stator having a stator core wound with a drive coil via an insulator, and a permanent magnet Magnet rotor, magnetic flux density distribution detecting means for detecting the magnetic flux density distribution of the magnet rotor, rectifying means for full-wave rectification of the AC power supply, and the high voltage obtained by the rectifying means is substantially flat low voltage DC voltage The low voltage DC voltage generated by the low voltage DC voltage conversion means is sequentially applied to the drive coil in a predetermined direction and in sequence based on the signal from the low voltage DC voltage conversion means for converting to a low voltage DC voltage conversion means and the magnetic flux density distribution detection means. Drive logic control means, a plurality of switching elements for energizing the drive coil based on the output of the drive logic control means, and the magnetic flux density distribution detection means The magnetic flux density distribution detection means is arranged so that the known magnetic flux density distribution waveform is substantially similar to the induced voltage waveform induced in the drive coil by the rotation of the magnet rotor, and the drive logic control is performed. The means includes: current waveform control means for supplying a current substantially similar to the waveform detected by the magnetic flux density distribution detection means to the drive coil; and supply power control means for controlling the average power supplied to the switching element to be substantially constant. An AC power supply direct connection type brushless DC motor comprising: a supply power changing means for changing the power controlled by the supply power control means to be substantially constant according to a connection location to the AC power supply connection means.   A magnetic flux density distribution waveform synthesizing unit for synthesizing two phases of the waveforms detected by the magnetic flux density distribution detecting unit is provided, and the drive logic control unit is substantially similar to the waveform synthesized by the magnetic flux density distribution waveform synthesizing unit. 5. The AC power supply direct-coupled brushless DC motor according to claim 4, wherein the drive logic control means is used to pass a current through the drive coil.   6. The AC power source directly connected brushless DC motor according to claim 1, wherein the permanent magnet of the magnet rotor is a polar anisotropic magnet.   7. The AC power supply directly connected brushless DC motor according to claim 1, wherein the drive logic control means is replaced with drive logic control means for forming a current waveform by PWM control. Direct connection type brushless DC motor.   An electric device equipped with the brushless DC motor directly connected to an AC power source according to claim 1.   The electrical device according to claim 8 is any one of a ventilator, a blower, a dehumidifier, a humidifier, a refrigeration device, and a fan filter unit.

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