阅读说明：本技术 用于交流风扇马达无段变速的驱动集成电路 (Drive integrated circuit for stepless speed change of alternating current fan motor ) 是由 林政宽 林淑蕙 于 2018-08-20 设计创作，主要内容包括：一种用于交流风扇马达无段变速的驱动集成电路包含感测单元、控制单元、脉宽调变单元、升压单元及驱动单元。感测单元感测一个交流风扇马达并产生一个至少指示所述交流风扇马达当前转速的感测输出,控制单元接收一个指示一个目标转速的输入信号,且包括一个查找表,查找表含有多个转速差值及多个分别对应转速差值的控制信号,控制单元根据该输入信号、该感测输出及查找表,产生一个转速控制信号,脉宽调变单元根据该转速控制信号产生一个调变信号,升压单元对该调变信号进行升压以产生一个升压信号,驱动单元根据该升压信号产生一个相关于该目标转速的驱动信号,且将该驱动信号输出至交流风扇马达,以降低生产成本。(A drive integrated circuit for stepless speed change of an alternating current fan motor comprises a sensing unit, a control unit, a pulse width modulation unit, a boosting unit and a drive unit. The control unit receives an input signal indicating a target rotating speed and comprises a lookup table, the lookup table comprises a plurality of rotating speed difference values and a plurality of control signals respectively corresponding to the rotating speed difference values, the control unit generates a rotating speed control signal according to the input signal, the sensing output and the lookup table, the pulse width modulation unit generates a modulation signal according to the rotating speed control signal, the boosting unit boosts the modulation signal to generate a boosting signal, the driving unit generates a driving signal related to the target rotating speed according to the boosting signal and outputs the driving signal to the alternating current fan motor so as to reduce the production cost.)

1. A drive ic for ac fan motor stepless speed change, adapted to receive a power signal from a power source and generate a drive signal to drive an ac fan motor stepless speed change, wherein the drive ic for ac fan motor stepless speed change comprises:

a sensing unit for sensing the AC fan motor to generate a sensing output indicating a current rotational speed of the AC fan motor and a rotor position of the AC fan motor;

the control unit receives an input signal indicating a target rotating speed, is electrically connected with the sensing unit to receive the sensing output, and comprises a storage module for storing a lookup table, wherein the lookup table comprises a plurality of rotating speed difference values and a plurality of control signals respectively corresponding to the rotating speed difference values;

the pulse width modulation unit is electrically connected with the control unit to receive the rotating speed control signal and generates a modulation signal with the regulated voltage according to the rotating speed control signal, and the pulse width of the modulation signal is changed along with the change of the rotating speed control signal;

the voltage boosting unit is electrically connected with the pulse width modulation unit to receive the modulation signal and boost the modulation signal to generate a boosted voltage signal; and

and the driving unit is electrically connected between the boosting unit and the alternating current fan motor, receives the boosting signal from the boosting unit, generates the driving signal related to the target rotating speed according to the boosting signal and outputs the driving signal to the alternating current fan motor.

2. The ic for a stepless speed change of an ac fan motor as claimed in claim 1, wherein said sensing unit is a hall sensing unit, and said sensing unit is used to continuously sense said ac fan motor.

3. The ic for ac fan motor stepless speed change according to claim 1, wherein the control unit is a programmable control unit, and the driving unit is a high voltage resistant unit.

4. The ic as claimed in claim 1, wherein the control unit subtracts the target speed indicated by the input signal from the current speed of the ac fan motor indicated by the sensing output to obtain a current speed difference, and performs a table lookup comparison from the lookup table according to the current speed difference, and uses one of the speed differences as the speed control signal corresponding to the speed difference corresponding to the current speed difference.

5. The drive integrated circuit for ac fan motor stepless speed change according to claim 1, wherein the drive unit comprises:

the signal switcher is provided with a first pin to an eighth pin, the first pin receives the power supply signal, the second pin and the third pin are electrically connected with the boosting unit and matched with the boosting unit to receive the boosting signal, and the fourth pin is electrically connected to the ground;

the first capacitor is electrically connected between the first pin and the fourth pin;

the diode is provided with an anode electrically connected with the first pin and a cathode electrically connected with the eighth pin;

the second capacitor is electrically connected between the sixth pin and the eighth pin;

the first resistor is provided with a first end electrically connected with the seventh pin and a second end;

the second resistor is provided with a first end electrically connected with the fifth pin and a second end;

a first transistor having a first terminal for receiving a bias voltage, a second terminal electrically connected to the sixth pin, and a control terminal electrically connected to the second terminal of the first resistor; and

a second transistor having a first terminal, a second terminal electrically connected to ground, and a control terminal electrically connected to the second terminal of the second resistor, wherein the outputs of the first terminal of the second transistor and the second terminal of the first transistor are used as the driving signal.

6. The ic as claimed in claim 5, wherein the first capacitor is a polar capacitor, and the first resistor and the second resistor are each a current limiting resistor.

Technical Field

The present invention relates to a driving integrated circuit, and more particularly, to a driving integrated circuit for driving an ac fan motor to continuously change speed.

Background

Disclosure of Invention

The present invention is directed to a driving ic for stepless speed change of ac fan motor, which can overcome the drawbacks of the prior art.

The drive integrated circuit for the stepless speed change of the alternating current fan motor is suitable for receiving a power supply signal from a power supply and generating a drive signal to drive the stepless speed change of the alternating current fan motor. The drive integrated circuit for the stepless speed change of the alternating current fan motor comprises a sensing unit, a control unit, a pulse width modulation unit, a boosting unit and a drive unit.

The sensing unit senses the AC fan motor and generates a sensing output indicating a current rotational speed of the AC fan motor and a rotor position of the AC fan motor.

The control unit receives an input signal indicating a target rotating speed, is electrically connected with the sensing unit to receive the sensing output, and comprises a storage module for storing a lookup table, wherein the lookup table comprises a plurality of rotating speed difference values and a plurality of control signals respectively corresponding to the rotating speed difference values, the control unit generates a rotating speed control signal related to the target rotating speed according to the input signal, the sensing output and the lookup table, and the rotating speed control signal is one of the control signals.

The pulse width modulation unit is electrically connected with the control unit to receive the rotating speed control signal and generates a modulation signal with the regulated voltage according to the rotating speed control signal, and the pulse width of the modulation signal is changed along with the change of the rotating speed control signal.

The boosting unit is electrically connected with the pulse width modulation unit to receive the modulation signal and boost the modulation signal to generate a boosting signal.

The driving unit is electrically connected between the boosting unit and the alternating current fan motor, receives the boosting signal from the boosting unit, generates the driving signal related to the target rotating speed according to the boosting signal, and outputs the driving signal to the alternating current fan motor.

The invention relates to a drive integrated circuit for stepless speed change of an alternating current fan motor, wherein a sensing unit is a Hall sensing unit, and the sensing unit is used for continuously sensing the alternating current fan motor.

The invention discloses a drive integrated circuit for stepless speed change of an alternating current fan motor, wherein a control unit is a programmable control unit, and a drive unit is a unit with high voltage resistance specification.

The control unit subtracts the target rotating speed indicated by the input signal from the current rotating speed of the alternating current fan motor indicated by the sensing output to obtain a current rotating speed difference value, performs table look-up comparison from the look-up table according to the current rotating speed difference value, and takes a control signal corresponding to the rotating speed difference value corresponding to one of the rotating speed difference values and the current rotating speed difference value as the rotating speed control signal.

The invention discloses a drive integrated circuit for stepless speed change of an AC fan motor, wherein the drive unit comprises:

the signal switcher is provided with a first pin to an eighth pin, the first pin receives the power supply signal, the second pin and the third pin are electrically connected with the boosting unit and matched with the boosting unit to receive the boosting signal, and the fourth pin is electrically connected to the ground;

the first capacitor is electrically connected between the first pin and the fourth pin;

the diode is provided with an anode electrically connected with the first pin and a cathode electrically connected with the eighth pin;

the second capacitor is electrically connected between the sixth pin and the eighth pin;

the first resistor is provided with a first end electrically connected with the seventh pin and a second end;

the second resistor is provided with a first end electrically connected with the fifth pin and a second end;

a first transistor having a first terminal for receiving a bias voltage, a second terminal electrically connected to the sixth pin, and a control terminal electrically connected to the second terminal of the first resistor; and

a second transistor having a first terminal, a second terminal electrically connected to ground, and a control terminal electrically connected to the second terminal of the second resistor, wherein the outputs of the first terminal of the second transistor and the second terminal of the first transistor are used as the driving signal.

The invention discloses a drive integrated circuit for stepless speed change of an alternating current fan motor, wherein a first capacitor is a polar capacitor, and a first resistor and a second resistor are respectively a current limiting resistor.

The invention has the beneficial effects that: the sensing unit, the control unit, the pulse width modulation unit, the boosting unit and the driving unit are integrated in a single driving integrated circuit, so that the driving integrated circuit has a smaller circuit area and requires lower manufacturing cost.

Drawings

FIG. 1 is a block diagram illustrating an embodiment of a driving IC for stepless speed change of an AC fan motor according to the present invention; and

fig. 2 is a circuit block diagram illustrating a driving unit of the embodiment.

Detailed Description

Referring to fig. 1, the driving ic 20 for the ac fan motor stepless speed change according to the present invention is adapted to be electrically connected between a power source 11 and an ac fan motor 12 including a rotor 121, receive a power signal VCC from the power source 11 and generate a driving signal Ds to drive the ac fan motor 12 stepless speed change. The driving integrated circuit 20 includes a sensing unit 2, a control unit 3, a pulse width modulation unit 4, a boosting unit 5, and a driving unit 6.

The sensing unit 2 continuously (or periodically) senses signals generated by SN polarity inversion of the ac fan motor 12 and the rotor 121 to generate a sensing output Ss indicating a current rotation speed of the ac fan motor 12 and a rotor position of the rotor 121 of the ac fan motor 12. In the present embodiment, the sensing unit 2 is a hall sensing unit.

The control unit 3 receives an input signal Is indicative of a target rotational speed and Is electrically connected to the sensing unit 2 to receive the sensing output Ss. The control unit 3 comprises a memory module 31 storing a look-up table 311, wherein the look-up table 311 comprises a plurality of rotation speed difference values and a plurality of control signals respectively corresponding to the rotation speed difference values. The control unit 3 generates a rotation speed control signal Cs related to the target rotation speed according to the input signal Is, the sensing output Ss and the lookup table 311, wherein the rotation speed control signal Cs Is one of the control signals. Specifically, the control unit 3 first subtracts the current rotation speed of the ac fan motor 12 indicated by the sensing output Ss from the target rotation speed indicated by the input signal Is to obtain a current rotation speed difference, then performs table lookup and comparison in the lookup table 311 according to the current rotation speed difference, and uses a control signal corresponding to the rotation speed difference corresponding to one of the rotation speed differences and the current rotation speed difference as the rotation speed control signal Cs.

It should be noted that, in the present embodiment, the control unit 3 is a programmable control unit. The input signal Is generated by a user from a user input interface (not shown) in response to an input operation corresponding to the target rotation speed, that Is, the user can arbitrarily adjust the target rotation speed, and the driving integrated circuit 20 generating the driving signal Ds according to the input signal Is can drive the ac fan motor 12 to achieve stepless speed change. The rotational speed difference and the control signal contained in the lookup table 311 are tables pre-established by the user through a programming setting, and the user can continuously update the lookup table 311. The speed control signal Cs is used to increase the speed of the ac fan motor 12, decrease the speed of the ac fan motor, or maintain the speed of the ac fan motor. For example, when the current speed difference is negative (or positive), which indicates that the current speed of the ac fan motor 12 is greater (or less) than the target speed, the control unit 3 is configured to decrease (or increase) the speed of the ac fan motor 12 according to the speed control signal Cs obtained from the lookup table 311 according to the current speed difference. When the current rotation speed difference is zero, it represents that the current rotation speed of the ac fan motor 12 is equal to the target rotation speed, and the rotation speed control signal Cs generated by the control unit 3 is used to maintain the rotation speed of the ac fan motor 12.

The pwm unit 4 is electrically connected to the control unit 3 to receive the rotation speed control signal Cs, and generates a modulation signal Ms with an adjusted voltage according to the rotation speed control signal Cs (the voltage of the modulation signal Ms is 12V), and the pulse width of the modulation signal Ms changes with the change of the rotation speed control signal Cs. For example, when the current speed difference is negative and the speed control signal Cs is used to rotate the ac fan motor 12 at a reduced speed, the pulse width of the modulation signal Ms is narrowed with the change of the speed control signal Cs. Conversely, when the current speed difference is positive and the speed control signal Cs is used to increase the speed of the ac fan motor 12, the pulse width of the modulation signal Ms is widened with the change of the speed control signal Cs.

The boosting unit 5 is electrically connected to the pwm unit 4 to receive the modulation signal Ms and boost the modulation signal Ms to generate a boosting signal Bs (the voltage of the boosting signal Bs is 24V-48V), so that the voltage of the boosting signal Bs is sufficient to drive the driving unit 6.

The driving unit 6 is electrically connected between the boosting unit 5 and the ac fan motor 12, and receives the boosting signal Bs from the boosting unit 5, generates the driving signal Ds related to the target rotation speed according to the boosting signal Bs, and outputs the driving signal Ds to the ac fan motor 12, so that the ac fan motor 12 rotates according to the driving signal Ds and drives a fan (not shown) to rotate at the target rotation speed, so that the fan generates a desired air volume. In the present embodiment, the driving unit 6 is a unit with high pressure resistance. The voltage of the driving signal Ds is 110V or 220V, and the frequency is 50Hz or 60 Hz. The driving unit 6 can drive the high-power alternating current fan motor with the required power of 20W-90W to rotate.

Further referring to fig. 2, the driving unit 6 includes a signal switch 61, first and second capacitors 62, 63, a diode 64, first and second resistors 65, 66, and first and second transistors 67, 68.

The signal switch 61 has first to eighth pins P1-P8, the first pin P1 receives the power signal VCC, the second and third pins P2, P3 are electrically connected to the voltage boosting unit 5 and cooperate to receive the voltage boosting signal Bs, and the fourth pin P4 is electrically connected to ground.

The first capacitor 62 is electrically connected between the first and fourth pins P1, P4. The second capacitor 63 is electrically connected between the sixth and eighth pins P6, P8. The diode 64 has an anode electrically connected to the first pin P1 and a cathode electrically connected to the eighth pin P8. The first resistor 65 has a first end electrically connected to the seventh pin P7, and a second end. The second resistor 66 has a first end electrically connected to the fifth pin P5, and a second end. The first transistor 67 has a first terminal for receiving a bias voltage VDD, a second terminal electrically connected to the sixth pin P6, and a control terminal electrically connected to the second terminal of the first resistor 65. The second transistor 68 has a first terminal, a second terminal electrically connected to ground, and a control terminal electrically connected to the second terminal of the second resistor 66. The outputs of the first terminal of the second transistor 68 and the second terminal of the first transistor 67 are used as the driving signal Ds.

It should be noted that, in the present embodiment, the first capacitor 62 is a polar capacitor, and the first and second resistors 65 and 66 are each a current limiting resistor. The first and second transistors 67 and 68 are each an N-type mosfet, wherein a drain, a source, and a gate of the N-type mosfet are the first terminal, the second terminal, and the control terminal of each of the first and second transistors 67 and 68, respectively. In addition, the signal switch 61 functions to shift the frequency of the boost signal Bs received by it by switching through its own internal switch to divide into outputting a signal from the seventh pin P7 to drive the first transistor 67 and outputting another signal from the fifth pin P5 to drive the second transistor 68. In addition, the signal switch 61 continuously detects whether the first transistor 67 is normally output or locked through the sixth pin P6, and if the first transistor 67 is locked, the signal switch 61 outputs a reset signal to the eighth pin P8 through the sixth pin P6 and the second capacitor 63 for resetting. The detailed circuit structure of the signal switch 61 has various implementation aspects and is well known to those skilled in the art, and therefore, is not described herein.

In summary, since the sensing unit 2, the control unit 3, the pwm unit 4, the boost unit 5, and the driving unit 6 are integrated in a single driving ic 20, the driving ic 20 has a smaller circuit area and requires a lower manufacturing cost than the conventional variable frequency driving apparatus. In addition, since the sensing unit 2 continuously senses the sensing output Ss obtained by the ac fan motor 12 to obtain the current rotation speed of the ac fan motor 12 and the rotor position of the rotor 121, the driving integrated circuit 20 can make a transistor (not shown) in the ac fan motor 12 reach zero-point switching according to the driving signal Ds generated by the sensing output Ss, so that the ac fan motor 12 does not generate an inverse electromotive force to the driving unit 6, thereby preventing the driving unit 6 from being damaged by the inverse electromotive force, and prolonging the service life of the driving integrated circuit 20 of this embodiment. Furthermore, the sensing unit 2 continuously senses the ac fan motor 12, so that the driving ic 20 can automatically adjust the driving signal Ds according to the sensing output Ss continuously output by the sensing unit 2, so that the driving ic 20 can achieve real speed detection and speed control for the ac fan motor 12, and avoid the situation that the rotational speed of the ac fan motor 12 does not reach the target rotational speed due to the quality difference or aging of the ac fan motor 12.

The above description is only an example of the present invention, and the scope of the present invention should not be limited thereby, and the invention is still within the scope of the present invention by simple equivalent changes and modifications made according to the claims and the contents of the specification.