CN103731087A

CN103731087A - Motor driving device with set minimum rotation speed and motor driving method

Info

Publication number: CN103731087A
Application number: CN201210393662.0A
Authority: CN
Inventors: 李灯辉; 余国庸
Original assignee: JINGZHI SEMICONDUCTOR CO Ltd
Current assignee: JINGZHI SEMICONDUCTOR CO Ltd; Amtek Semiconductor Co Ltd
Priority date: 2012-10-16
Filing date: 2012-10-16
Publication date: 2014-04-16
Anticipated expiration: 2032-10-16
Also published as: CN103731087B

Abstract

The invention provides a motor driving device with set minimum rotation speed and a motor driving method. The motor driving device is composed of a PWM conversion circuit, an oscillating circuit, a comparator and a control unit. The PWM conversion circuit is used for converting input adjustable maximum set voltage signals (VH), adjustable minimum set voltage signals (VL) and control signals to analog signals (VTH), and the analog signals, triangular wave signals (TRI) generated by the oscillating circuit and adjustable minimum rotation speed set voltage signals (ALG) are input to the comparator for comparison, so that driving signals are output to the control unit to control rotation speed of a motor. The motor driving device and motor driving method can be used for adjusting different motor rotation speed curves and setting the minimum rotation speed of the motor, so that the function of changing the rotation speed of the motor is achieved to maintain the minimum work torque of the motor, and motor control flexibility can be improved.

Description

There is motor drive and driving method thereof that minimum speed is set

Technical field

The invention relates to a kind of motor drive and driving method thereof, relate to especially a kind of motor drive and driving method thereof that minimum speed is set that have; By motor drive circuit and the driving method thereof with minimum speed setting of the present invention, can be used to adjust different motor rotary speed curve and can be in order to set motor minimum speed, and then reach and change the function of motor rotary speed and maintain the minimum work moment of motor.

Background technology

Tradition is with pulse-width modulation (Pulse Width Modulation, PWM) control the mode that motor drives, cannot reach the adjustable function of speed curves, be all the work period (Duty cycle) of inputting to be how many, and the rotating speed of relatively required motor output is exactly how many.For instance, refer to Fig. 1, it is the curve of output schematic diagram driving for known pulse-width modulation control motor, as shown in Figure 1, the work period of PWM is 0% to 100%, when the work period of PWM is 50%, corresponding motor can be exported 50% rotating speed, therefore at the control curve of motor rotary speed, will present a kind of curve of linearity.

General under identical motor load in order to reach the requirement of minimum heat radiation, and reduce motor and restart produced noise, noise, conventionally in the PWM work period, lowly after certain value, can wish that motor is fixed on a rotating speed, not because the output of PWM work period is less than the minimum work moment of motor, and motor is stopped operating.

But, when user wants to change according to actual operating state the rotating speed of motor, the PWM work period that conventionally can input by change, or change the coil design of motor.But above-mentioned two kinds of modes have the difficulty place in practical operation.For example: when wanting to change PWM work period of controller input along with practical operation situation, just must change the control mode of whole system; And if will change the coil of motor time, must change motor.

Therefore, the invention provides a kind of motor drive and driving method thereof that minimum speed is set that have, except setting by the voltage between adjustment different adjustable the highest setting voltage signal (VH), adjustable minimum setting voltage signal (VL) and triangular signal (TRI), and adjustable minimum speed setting voltage signal is in order to keep the minimum work moment of motor, to maintain the requirement of minimum heat radiation, motor drive is had and change the function of motor rotary speed and there is the function that minimum speed is set, to increase the flexibility ratio of motor applications.

Summary of the invention

In order to solve above-mentioned relevant problem, a main purpose of the present invention is to provide a kind of motor drive that minimum speed is set that has, first pass through PWM change-over circuit by the adjustable the highest setting voltage signal (VH) of input, adjustable minimum setting voltage signal (VL) converts analog signal (VTH) to control signal, the triangular signal (TRI) again the analog signal of PWM output that change-over circuit is changed and an oscillating circuit being produced and an additional adjustable minimum speed setting voltage signal together input to comparator make comparisons after, to produce an output drive signal, again this output drive signal is delivered to control unit to control the rotating speed of motor.Therefore the present invention thus motor drive adjusts different motor rotary speed curve and can be in order to set motor minimum speed, and then reach and change the function of motor rotary speed and maintain the minimum work moment of motor, and to increase the flexibility ratio of motor control.

The another main purpose of the present invention is to provide a kind of motor driving method of capable of regulating motor rotary speed, outside setting by the voltage between the highest adjustable setting voltage signal (VH), adjustable minimum setting voltage signal (VL) and triangular signal (TRI), and adjustable minimum speed setting voltage signal, not only can adjust different motor rotary speed curves, also can maintain the minimum work moment of motor, to increase the flexibility ratio of motor control.

According to above-mentioned projects, the invention provides a kind of motor drive that minimum speed is set that has, comprise: a PWM change-over circuit, there is a first input end, one second input, one the 3rd input and an output, wherein first input end is connected with a control signal, the second input is connected with the highest adjustable setting voltage signal (VH), the 3rd input is connected with an adjustable minimum setting voltage signal (VL), and export an analog signal (VTH) by output, wherein, this analog signal can be by adjusting this control signal, this is adjustable, and the highest setting voltage signal (VH) or this adjustable minimum setting voltage signal (VL) change, one oscillating circuit is to produce a triangular signal (TRI), an and comparator, there is a first input end, one second input, one the 3rd input and an output, the triangular signal that wherein first input end produces with oscillating circuit is connected, the second input is connected with the analog signal that PWM change-over circuit is exported, the 3rd input receives an adjustable minimum speed setting voltage signal, and drives signal by output output one.

The invention provides a kind of motor driving method that minimum speed is set that has, comprise: a PWM change-over circuit is provided, it has a first input end, one second input, one the 3rd input and an output, wherein first input end is connected with a pwm signal, the second input is connected with the highest adjustable setting voltage signal (VH), the 3rd input is connected with an adjustable minimum setting voltage signal (VL), and exports an analog signal (VTH) by this output; Provide an oscillating circuit, in order to produce a triangular signal; And provide a comparator, it has a first input end, one second input, one the 3rd input and an output, this triangular signal that wherein this first input end produces with this oscillating circuit is connected, this second input is connected with this analog signal that this PWM change-over circuit is exported, the 3rd input receives an adjustable minimum speed setting voltage signal, and drives signal by this output output one; Wherein, by adjusting the highest adjustable setting voltage signal (VH) or adjustable minimum setting voltage signal (VL), change the curve of analog signal (VTH).

Via motor drive and the driving method thereof with minimum speed setting provided by the present invention, make motor drive by adjusting control signal, the highest adjustable setting voltage signal (VH), adjustable minimum setting voltage signal (VL) is to produce after an analog signal, again this analog signal and triangular signal (TRI) and an additional adjustable minimum speed setting voltage signal are together inputed to comparator and compare and produce a driving signal, by this, drive signal to control different motor rotary speed curves, make motor drive of the present invention and change the function of motor rotary speed and can also maintain the minimum work moment of motor except reaching, and then the flexibility ratio of increase motor applications.

Accompanying drawing explanation

In order to describe structure of the present invention and feature place in detail, below in conjunction with preferred embodiment and coordinate accompanying drawing explanation as after, wherein:

Fig. 1 is the curve of output schematic diagram that known pulse-width modulation control motor of the present invention drives;

Fig. 2 is motor drive Organization Chart of the present invention;

Fig. 3 is PWM change-over circuit figure of the present invention;

Fig. 4 is analog signal Output rusults schematic diagram after conversion of the present invention;

Fig. 5 A is first embodiment of the present invention oscillogram;

Fig. 5 B is the speed curves figure of the first embodiment of the present invention;

Fig. 6 A is the oscillogram that the additional minimum speed of the first embodiment of the present invention is set;

Fig. 6 B is the speed curves figure that the additional minimum speed of the first embodiment of the present invention is set;

Fig. 7 A is second embodiment of the present invention oscillogram;

Fig. 7 B is the speed curves figure of the second embodiment of the present invention;

Fig. 8 A is the oscillogram that the additional minimum speed of the second embodiment of the present invention is set;

Fig. 8 B is the speed curves figure that the additional minimum speed of the second embodiment of the present invention is set;

Fig. 9 A is third embodiment of the present invention oscillogram;

Fig. 9 B is the speed curves figure of the third embodiment of the present invention;

Figure 10 A is the oscillogram that the additional minimum speed of the third embodiment of the present invention is set;

Figure 10 B is the speed curves figure that the additional minimum speed of the third embodiment of the present invention is set;

Figure 11 is motor driving method flow chart of the present invention.

Embodiment

Because the present invention discloses a kind of motor drive and driving method thereof that minimum speed is set that have, by the adjustable the highest setting voltage signal (VH) of input by PWM change-over circuit, adjustable minimum setting voltage signal (VL) converts analog signal (VTH) to control signal, the triangular signal (TRI) again this analog signal and oscillating circuit being produced and an additional adjustable minimum speed setting voltage signal together input to comparator make comparisons after, to produce an output drive signal, again this output drive signal is delivered to control unit to control the rotating speed of motor.And the basic principle of the motor relevant with the present invention and function have known that for correlative technology field has the knowledgeable can understand conventionally, therefore with explanation hereinafter, only for being elaborated with motor drive of the present invention and its feature place of driving method thereof.In addition, the accompanying drawing in following interior literary composition, also not according to the actual complete drafting of relative dimensions, its effect is only being expressed the schematic diagram relevant with feature of the present invention.

First, referring to Fig. 2, is to be motor drive Organization Chart of the present invention.As shown in Figure 2, motor drive comprises: a PWM change-over circuit 10, there is a first input end, one second input, one the 3rd input and an output, wherein first input end is connected with a control signal 101, the second input is connected with the highest adjustable setting voltage signal (VH) 102, the 3rd input is connected with an adjustable minimum setting voltage signal (VL) 103, and export an analog signal (VTH) by output, wherein control signal is a pwm signal (for example: a pwm signal being provided by personal computer system), and this analog signal can be by adjusting this control signal, this is adjustable, and the highest setting voltage signal (VH) or this adjustable minimum setting voltage signal (VL) change, one oscillating circuit 12, is to produce a triangular signal (TRI), and wherein triangular signal can be adjusted between a high voltage level and a low-voltage level, one comparator 14, it has a first input end, one second input, one the 3rd input and an output, the triangular signal (TRI) that wherein a first input end produces with oscillating circuit 12 is connected, the analog signal (VTH) that one the second input is exported with PWM change-over circuit 10 is connected, one the 3rd input receives an adjustable minimum speed setting voltage signal 141, and drives signal (S_DR) by this output output one, and a control unit 16, be to drive signal (S_DR) to control a motor 18 in order to receive, wherein motor is to be a single-phase motor or a three-phase motor.

Then, referring to Fig. 3, is to be PWM change-over circuit figure of the present invention.As shown in Figure 3, PWM change-over circuit 10 has a first input end, one second input, one the 3rd input and an output, wherein first input end is connected with a control signal 101, the second input is connected with the highest adjustable setting voltage signal (VH) 102, the 3rd input is connected with an adjustable minimum setting voltage signal (VL) 103, and export an analog signal (VTH) by output, wherein this control signal is to be a pwm signal (for example: a pwm signal being provided by personal computer system), and this analog signal can be by adjusting this control signal, this is adjustable, and the highest setting voltage signal (VH) or this adjustable minimum setting voltage signal (VL) change, and PWM change-over circuit further comprises one first operational amplifier (OP1), there is a positive input terminal and be electrically connected at adjustable the highest setting voltage signal 102, a negative input end, and an output is electrically connected at negative input end, one second operational amplifier (OP2), has a positive input terminal and be electrically connected at adjustable minimum setting voltage signal 103, a negative input end, and an output is electrically connected at negative input end, one first switch element (TG1), one input with reception one first input signal is coupled to the first operational amplifier (OP1), is coupled to an output of an output node (VA), is coupled to a control end of control signal 101 and is coupled to a link of a common node (N), whether the first switch element (TG1) can determine conducting the first input signal according to control signal 101, and wherein the first switch element (TG1) is to be a transmission lock, one second switch element (TG2), one input with reception one second input signal is coupled to the second operational amplifier (OP2), is coupled to an output of output node (VA), is coupled to a control end of control signal 101 and is coupled to a link of this common node (N), whether second switch element (TG2) can determine conducting the second input signal according to control signal 101, and wherein second switch element (TG2) is to be a transmission lock, one inverter 20, having an input is in order to reception control signal 101, and its output is connected in common node (N), an and low-pass filter circuit 22, it is that a voltage transitions in order to output node (VA) is produced becomes analog signal (VTH), wherein low-pass filter circuit 22 is to be a second-order low-pass filter circuit, further comprise one first resistance (R1), there is a first end, be coupled to output node (VA), and one second end, one second resistance (R2), has a first end, is coupled to the second end of the first resistance (R1), and one second end, one first electric capacity (C1), has a first end, is coupled to the second resistance (R2), and one second end is coupled to earth terminal, one the 3rd operational amplifier (OP3), there is a positive input terminal and be electrically connected at contact, the negative input end between the second resistance (R2) and the first electric capacity (C1), and one output be electrically connected at negative input end, in order to outputting analog signal (VTH), and one second electric capacity (C2), there is a first end, be coupled to the contact between the first resistance (R1) and the second resistance (R2), and one second end is coupled to the output of the 3rd operational amplifier (OP3).

When control signal 101 inputs to after PWM change-over circuit 10 via the first input end of PWM change-over circuit 10, can convert an analog signal (VTH) to by the adjustable the highest setting voltage signal (VH) 102 of the second input input of PWM change-over circuit 10 and the adjustable minimum setting voltage signal (VL) 103 of the 3rd input input of PWM change-over circuit 10, wherein control signal 101 is to be a pwm signal, its work period (Duty cycle) can be by 0% to 100% variation, the highest adjustable setting voltage signal (VH) 102 and adjustable minimum setting voltage signal (VL) 103 can be via external input settings.After completing via external input setting, the highest adjustable setting voltage signal (VH) 102 can input to the positive input terminal of the first operational amplifier (OP1), exports the input of the first input signal to the first switch element (TG1) after the first operational amplifier (OP1) computing through output, adjustable minimum setting voltage signal (VL) 103 can input to the positive input terminal of the second operational amplifier (OP2), after the second operational amplifier (OP2) computing, through output, exports the input of the second input signal to second switch element (TG2), and control signal 101 can with the input of inverter 20, the control end of the control end of the first switch element (TG1) and second switch element (TG2) connects, utilize control signal 101 the highest adjustable setting voltage signal (VH) 102 to be outputed to output node (VA) after by the first operational amplifier (OP1) computing or adjustable minimum setting voltage signal (VL) 103 is outputed to output node (VA) after by the second operational amplifier (OP2) computing, adjustable the highest setting voltage signal (VH) 102 via a low-pass filter circuit 22, output node (VA) being sampled to again afterwards or adjustable minimum setting voltage signal (VL) 103 convert an analog signal (VTH) to and export comparator 14 to, and then control motor 18.

Follow, refer to Fig. 4 and coordinate Fig. 3, Fig. 4 is to be analog signal (VTH) Output rusults schematic diagram after conversion of the present invention.As shown in Figure 4, analog signal (VTH) is to control the highest adjustable setting voltage signal (VH) or adjustable minimum setting voltage signal (VL) exports output node (VA) to and changed output by control signal 101, wherein analog signal (VTH) is changed by a conversion formula, and conversion formula is as shown in the formula shown in (1):

Its work period of VTH=(VH-VL) × control signal (Duty cycle)+VL (1)

But, set different the highest adjustable setting voltages (VH) or adjustable minimum setting voltage signal (VL) and can produce different analog signal (VTH) results after conversion formula conversion.For instance, if its work period of control signal (Duty cycle) of input is fixed as to 20%, also soon its work period of pwm signal (Duty cycle) is fixed as 20%, the analog signal (VTH) that the adjustable the highest setting voltage signal (VH) that overview setup is different or adjustable minimum setting voltage signal (VL) produce; For example: when setting the highest adjustable setting voltage signal (VH)=5V, adjustable minimum setting voltage signal (VL)=0V, after conversion formula conversion, can produce analog signal (VTH)=1V; When setting the highest adjustable setting voltage signal (VH)=3.75V, adjustable minimum setting voltage signal (VL)=1.25V, after conversion formula conversion, can produce analog signal (VTH)=1.75V; And when setting the highest adjustable setting voltage signal (VH)=3V, adjustable minimum setting voltage signal (VL)=1.5V, after conversion formula conversion, can produce analog signal (VTH)=1.8V.If the control signal (that is pwm signal) its work period (Dutycycle) of input is fixed as to 60%, the analog signal (VTH) that the adjustable the highest setting voltage signal (VH) that overview setup is different or adjustable minimum setting voltage signal (VL) produce, for example: when setting the highest adjustable setting voltage signal (VH)=5V, adjustable minimum setting voltage signal (VL)=0V, after conversion formula conversion, can produce analog signal (VTH)=3V; When setting the highest adjustable setting voltage signal (VH)=3.75V, adjustable minimum setting voltage signal (VL)=1.25V, after conversion formula conversion, can produce analog signal (VTH)=2.75V; And when setting the highest adjustable setting voltage signal (VH)=3V, adjustable minimum setting voltage signal (VL)=1.5V, after conversion formula conversion, can produce analog signal (VTH)=2.4V.Described in above, when control signal (that is pwm signal) its work period (Dutycycle) is by 0% during to 100% variation, set different adjustable the highest setting voltage signals (VH) or adjustable minimum setting voltage signal (VL), the result of the analog signal (VTH) producing after conversion formula conversion can present a kind of variation of linearity.But, by adjusting control signal, the highest adjustable setting voltage signal (VH) or adjustable minimum setting voltage signal (VL), can be used to change analog signal, the triangular signal (TRI) again the analog signal of generation and oscillating circuit 12 being produced compares and can produce one and drive signal, its drive signal be produce different output speeds than (Duty%) to control revolution, can reach and change the function of motor rotary speed.

Therefore, please first consulting Fig. 5 A, is the waveform schematic diagram for the first embodiment of the present invention.As shown in Figure 5A, the first embodiment be first the high voltage of triangular signal (TRI) is fixed as to 3.75V, low-voltage is fixed as 1.25V, and the highest adjustable setting voltage signal (VH) is fixed on to 3.75V removes to adjust adjustable minimum setting voltage signal (VL), the analog signal (VTH) producing after conversion formula conversion compares itself and triangular signal (TRI), and observes its output speed than (Duty%), therefore be further divided into the result that three kinds of states illustrate comparison: ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3.75V, VL=0V), CASE2 (VH=3.75V, VL=2.25V), first, suppose under the state of ORG, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, and adjustable minimum setting voltage signal (VL) is made as 1.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Fig. 5 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its output speed can be a linear change than (Duty%), secondly, suppose under the state of CASE1, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, and adjustable minimum setting voltage signal (VL) changes and is made as 0V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 0V to 3.75V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Fig. 5 A, because analog signal (VTH) is to be started to change by 0V, when being changed to 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), therefore analog signal (VTH) does not have output speed than (Duty%) when 0V to 1.25V, again secondly, suppose under the state of CASE2, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, and adjustable minimum setting voltage signal (VL) changes and is made as 2.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 2.25V to 3.75V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Fig. 5 A, when being 2.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now also higher than the low-voltage 1.25V of triangular signal (TRI), therefore in CASE2 state, there is at the very start output speed than (Duty%).

Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3.75V, VL=0V), CASE2 (VH=3.75V, VL=2.25V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Fig. 5 B and coordinate Fig. 5 A, as shown in Figure 5 B, the speed curves figure for the first embodiment of the present invention, transverse axis is to be its work period of control signal (that is pwm signal) (Duty cycle%), the longitudinal axis is for motor output speed is than (Duty%), observe speed curves under ORG state in the work period (Dutycycle) by 0% to 100% variation, described in Fig. 5 A, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its motor output speed curve can be the variation of a linearity, then, observe speed curves under its CASE1 state in the work period (Dutycycle) by 0% to 100% variation, described in Fig. 5 A, because analog signal (VTH) is to be started to change by 0V, when being changed to 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), therefore analog signal (VTH) is there is no output speed than (Duty%) when 0V to 1.25V, as the CASE1 speed curves of Fig. 5 B, when the work period, (Duty cycle) was 33%, motor just starts to have the output of rotating speed, observe again the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE2 state, described in Fig. 5 A, when being 2.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now also higher than the low-voltage 1.25V of triangular signal (TRI), therefore in the output that has at the very start motor rotary speed, as the CASE2 speed curves of Fig. 5 B, in the work period, when being 0%, (Duty cycle) just have 40% motor output speed than (Duty%), comprehensive the above, the first embodiment can be used for after motor rotary speed is reduced to a certain degree, can adjust in response to different motors and different system demand, when motor need to maintain minimum heat-sinking capability, just can adjust to the setting of CASE2, if system does not need to do to dispel the heat at this moment, and while requiring energy saver mode, can adjust to the setting of CASE1, after pwm signal is less than 33% (can according to system requirements adjustment), motor just can not output signal.These two kinds of system requirements above, can be by the output (as shown in the dotted line of Fig. 5 B) that to adjust adjustable minimum setting voltage signal (VL) be capable of regulating motor when the slow-speed of revolution.But, for fear of motor rotary speed is low, stop operating afterwards to a certain degree, therefore can wish that motor is fixed on a rotating speed, the function that can set by minimum speed, controls motor and keeps the requirement of minimum heat radiation and take into account energy-conservation effectiveness.

Please continue to refer to Fig. 6 A, Fig. 6 A is the waveform schematic diagram of setting for the additional minimum speed of the first embodiment of the present invention.For convenience of description, the adjusting range of the CASE1 of Fig. 5 B and CASE2 is narrowed down to 20%DUTY by 40%DUTY, as shown in the dotted line of Fig. 6 B.Referring again to Fig. 6 A, in three kinds of state ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3.75V, VL=0.625V), CASE2 (VH=3.75V, VL=1.75V), configured an adjustable minimum speed setting voltage signal (ALG), itself and the analog signal (VTH) producing after conversion formula conversion are together compared with triangular signal (TRI), determine that according to this its output speed is than (Duty%).As shown in Figure 6A, suppose under the state of ORG, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, adjustable minimum setting voltage signal (VL) is made as 1.25V, and additional adjustable minimum speed setting voltage signal (ALG) is made as to 2V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Fig. 6 A.Refer to the ORG oscillogram of Fig. 6 A the explanation according to the ORG oscillogram of Fig. 5 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), can between 1.25V to 3.75V, change, but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change.Secondly, suppose under the state of CASE1, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, adjustable minimum setting voltage signal (VL) changes and is made as 0.625V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 1.75V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 0.625V to 3.75V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Fig. 6 A, refer to the CASE1 oscillogram of Fig. 6 A the explanation according to the CASE1 oscillogram of Fig. 5 A, because analog signal (VTH) is to be started to change by 0V, when being changed to 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but stop operating and cause no-output rotating ratio (Duty%) for fear of motor, therefore adjustable minimum speed setting voltage signal (ALG) 1.75V is set and to control motor, maintains minimum speed, when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change, again secondly, suppose under the state of CASE2, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is fixed on to 3.75V, adjustable minimum setting voltage signal (VL) changes and is made as 1.75V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 2.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.75V to 3.75V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Fig. 6 A, refer to the CASE2 oscillogram of Fig. 6 A the explanation according to the CASE2 oscillogram of Fig. 5 A, when being 1.75V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now also higher than the low-voltage 1.25V of triangular signal (TRI), therefore in CASE2 state, there is at the very start output speed than (Duty%), if but motor is because producing a large amount of heat excess Temperatures, in order to reach the demand of heat radiation, therefore additional adjustable minimum speed setting voltage signal (ALG) 2.25V maintains minimum speed and effectively regulates temperature to control motor, when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change.

Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3.75V, VL=0.625V), CASE2 (VH=3.75V, VL=1.75V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Fig. 6 B and coordinate Fig. 6 A, as shown in Figure 6B, the speed curves figure setting for the additional minimum speed of the first embodiment of the present invention, transverse axis is to be control signal (that is pwm signal) its work period (Dutycycle%), the longitudinal axis is for motor output speed is than (Duty%), observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under ORG state, according to described in Fig. 6 A and coordinate Fig. 6 B, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 30% than (Duty%), that is between work period (Duty cycle) in 0% to 30%, its output speed can maintain 30% than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 30% after), its output speed can be a linear change than (Duty%) result.Then, observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE1 state, according to described in Fig. 6 A and coordinate 6B, because analog signal (VTH) is to be started to change by 0.625V, when being changed to 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but stop operating and cause no-output rotating ratio (Duty%) for fear of motor, therefore adjustable minimum speed setting voltage signal (ALG) 1.75V is set and to control motor, maintains minimum speed, when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 20% than (Duty%), that is between the work period (Dutycycle) in 0% to 35%, its output speed can maintain 20% than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 36% after), its output speed can be a linear change than (Duty%) result.Observe again the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE2 state, according to described in Fig. 6 A and coordinate Fig. 6 B, when being 1.75V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now also higher than the low-voltage 1.25V of triangular signal (TRI), therefore in CASE2 state, there is at the very start output speed than (Duty%), but can cause motor to produce a large amount of heat and excess Temperature, in order to reach the demand of heat radiation, therefore additional adjustable minimum speed setting voltage signal (ALG) 2.25V maintains minimum speed and effectively regulates temperature to control motor, when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 40% than (Duty%), that is between work period (Duty cycle) in 0% to 25%, its output speed can maintain 40% than (Duty%), when analog signal (VTH) is greater than after the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 25% after), its output speed can be a linear change than (Duty%) result.Comprehensively the above, can, in order to remain motor operated in minimum speed, also can adjust in response to different motors and different system demand after the additional minimum speed setting of the first embodiment.

Then, please continue to refer to Fig. 7 A, be, the oscillogram for the second embodiment of the present invention.As shown in Figure 7 A, the second embodiment be first the high voltage of triangular signal (TRI) is fixed as to 3.75V, low-voltage is fixed as 1.25V, and adjustable minimum setting voltage signal (VL) be fixed on to 1.25V remove to adjust the highest adjustable setting voltage signal (VH), the analog signal (VTH) producing after conversion formula conversion by it with triangular signal (TRI) comparison and observe its output speed than (Duty%), therefore be further divided into three kinds of states comparative result is described: ORG (VH=3.75V, VL=1.25V), CASE1 (VH=2.9V, VL=1.25V), CASE2 (VH=5V, VL=1.25V), first, suppose (the VH=3.75V in ORG, VL=1.25V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 3.75V, and adjustable minimum setting voltage signal (VL) is fixed on 1.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Fig. 7 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its output speed can be a linear change than (Duty%), secondly, suppose (the VH=2.9V in CASE1, VL=1.25V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 2.9V, and adjustable minimum setting voltage signal (VL) is equally fixed on 1.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 2.9V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 2.9V low compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), again secondly, suppose (the VH=5V in CASE2, VL=1.25V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 5V, and adjustable minimum setting voltage signal (VL) is equally fixed on 1.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 5V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%).Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=2.9V, VL=1.25V), CASE2 (VH=5V, VL=1.25V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Fig. 7 B and coordinate Fig. 7 A, as shown in Figure 7 B, the speed curves figure for the second embodiment of the present invention, transverse axis is to be control signal (that is pwm signal) its work period (Dutycycle%), the longitudinal axis is for motor output speed is than (Duty%), observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under ORG state, described in Fig. 7 A, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its motor output speed curve can be linear variation, then, observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE1 state, described in Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 2.9V low compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), as the CASE1 speed curves of Fig. 7 B, in the work period, when being 100%, (Duty cycle) only have 67% motor output speed than (Duty%), observe again the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE2 state, described in Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), as the CASE2 speed curves of Fig. 7 B, in the work period, when being 67%, (Duty cycle) just reach 100% motor output speed than (Duty%), comprehensive the above, the second embodiment can be used for the setting of the corresponding motor radiating ability of different system demand, heat-sinking capability as required in system, do not need when very large, be adjustable to the setting of CASE1, heat-sinking capability as required in system, need to output to ahead of time maximum, be adjustable to the setting of CASE2, therefore when the radiator fan excess Temperatures such as VGA or CPU, in order effectively to regulate temperature, can adjust the output (as the dotted line of Fig. 7 B as shown in be represent adjustable scope) of motor when the high rotating speed by adjustment the highest adjustable setting voltage signal (VH), use the temperature that reduces radiator fan.But for the temperature of fast reducing radiator fan, the function that also can set by minimum speed, controls motor and reaches the demand of heat radiation and take into account energy-conservation effectiveness.

Refer to Fig. 8 A, Fig. 8 A is the waveform schematic diagram of setting for the additional minimum speed of the second embodiment of the present invention.Clearly, difference between Fig. 8 A and Fig. 7 A is only: Fig. 8 A has configured an adjustable minimum speed setting voltage signal (ALG) in three kinds of state ORG (VH=3.75V, VL=1.25V), CASE1 (VH=2.9V, VL=1.25V), CASE2 (VH=5V, VL=1.25V), itself and the analog signal (VTH) producing after conversion formula conversion are together compared with triangular signal (TRI), determine that according to this its output speed is than (Duty%).As shown in Figure 8 A, suppose under the state of ORG, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 3.75V, adjustable minimum setting voltage signal (VL) is fixed on 1.25V, and additional adjustable minimum speed setting voltage signal (ALG) is made as to 2V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Fig. 8 A, refer to the ORG oscillogram of Fig. 8 A the explanation according to the ORG oscillogram of Fig. 7 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), can between 1.25V to 3.75V, change, but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change, secondly, suppose under the state of CASE1, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 2.9V, adjustable minimum setting voltage signal (VL) is equally fixed on 1.25V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 1.75V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 2.9V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Fig. 8 A, refer to the CASE1 oscillogram of Fig. 8 A the explanation according to the CASE1 oscillogram of Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 2.9V low compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 1.75V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change, again secondly, suppose under the state of CASE2, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 5V, adjustable minimum setting voltage signal (VL) is equally fixed on 1.25V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 2.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 5V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Fig. 8 A, refer to the CASE2 oscillogram of Fig. 8 A the explanation according to the CASE2 oscillogram of Fig. 7 A, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 2.25V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change.

Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=2.9V, VL=1.25V), CASE2 (VH=5V, VL=1.25V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Fig. 8 B and coordinate Fig. 8 A, as shown in Figure 8 B, the speed curves figure setting for the additional minimum speed of the second embodiment of the present invention, transverse axis is to be control signal (that is pwm signal) its work period (Dutycycle%), the longitudinal axis is for motor output speed is than (Duty%), observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under ORG state, according to described in Fig. 8 A and coordinate Fig. 8 B, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 30% than (Duty%), that is between work period (Duty cycle) in 0% to 30%, its output speed can maintain 30% than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 30% after), its output speed can be a linear change than (Duty%) result.Then, observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE1 state, according to described in Fig. 8 A and coordinate 8B, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 2.9V low compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 1.75V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 20% than (Duty%), that is between work period (Duty cycle) in 0% to 30.3%, its output speed can maintain 20% than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 30.3% after), its output speed can be a linear change than (Duty%) result.Observe again speed curves under its CASE2 state in the work period (Dutycycle) by 0% to 100% variation, according to described in Fig. 8 A and coordinate Fig. 8 B, when being 1.25V, analog signal (VTH) contacts with triangular signal (TRI), current potential is now consistent with the low-voltage 1.25V of triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 2.25V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 40% than (Duty%), that is between work period (Duty cycle) in 0% to 26.6%, its output speed can maintain 40% than (Duty%), when analog signal (VTH) is greater than after the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 26.6% after), its output speed can be a linear change than (Duty%) result.Comprehensively the above, can, in order to remain motor operated in minimum speed, also can adjust in response to different motors and different system demand after the additional minimum speed setting of the second embodiment.

Then, please continue to refer to Fig. 9 A, be, the oscillogram for the third embodiment of the present invention.As shown in Figure 9 A, the 3rd embodiment is first fixed as the high voltage of triangular signal (TRI) 3.75V, the fixing 1.25V of low-voltage, and remove to adjust adjustable minimum setting voltage signal (VL) and the highest adjustable setting voltage signal (VH) simultaneously, the analog signal (VTH) producing after conversion formula conversion compares itself and triangular signal (TRI) and observe its output speed than (Duty%), therefore be further divided into three kinds of states comparative result is described: ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3V, VL=2V), CASE2 (VH=5V, VL=0V), first, suppose (the VH=3.75V in ORG, VL=1.25V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, adjustable minimum setting voltage signal (VL) is made as to 1.25V, and the highest adjustable setting voltage signal (VH) is made as 3.75V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Fig. 9 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its output speed can be a linear change than (Duty%), secondly, suppose (the VH=3V in CASE1, VL=2V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 3V, and adjustable minimum setting voltage signal (VL) is made as 2V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 2V to 3V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Fig. 9 A, when being 2V, analog signal (VTH) contacts with triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, and current potential now can be higher than the low-voltage 1.25V of triangular signal (TRI), thereby institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 1.25V under ORG state than (Duty%), moreover to turn to 3V low compared with the high voltage 3.75V of triangular signal (TRI) due to the hypermutation of analog signal (VTH), thereby institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), then, suppose again (the VH=5V in CASE2, VL=0V) under state, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 5V, and adjustable minimum setting voltage signal (VL) is made as 0V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 0V to 5V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Fig. 9 A, because analog signal (VTH) is to be started to change by 0V, when being 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%).Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3V, VL=2V), CASE2 (VH=5V, VL=0V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Fig. 9 B and coordinate Fig. 9 A, as shown in Figure 9 B, the speed curves figure for the third embodiment of the present invention, transverse axis is to be control signal (that is pwm signal) its work period (Dutycycle%), the longitudinal axis is for motor output speed is than (Duty%), observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under ORG state, described in Fig. 9 A, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), therefore its motor output speed can be the variation of a linearity, then, observe the speed curves variation by 0% to 100% in the work period (Duty cycle) in its CASE1 situation, described in Fig. 9 A, when being 2V, analog signal (VTH) contacts with triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, and current potential now can be higher than the low-voltage 1.25V of triangular signal (TRI), thereby institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 1.25V under ORG state than (Duty%), moreover to turn to 3V low compared with the high voltage 3.75V of triangular signal (TRI) due to the hypermutation of analog signal (VTH), thereby institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), as the CASE1 speed curves of Fig. 9 B, in the work period (Duty cycle), be 0% just to have 30% motor output speed than (Duty%), when the work period, when being 100%, (Duty cycle) only have 70% motor output speed than (Duty%), observe again the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE2 state, described in Fig. 9 A, because analog signal (VTH) is to be started to change by 0V, when being 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), as the CASE2 speed curves of Fig. 9 B, when the work period, (Duty cycle) was 25%, motor just starts to have the output of rotating speed, and motor output speed just reaches 100% than (Duty%) when the work period, (Duty cycle) was 67%, comprehensive the above, the 3rd embodiment can adjust the output (as the dotted line of Fig. 9 B as shown in) of motor when high rotating speed and the slow-speed of revolution by adjust the highest adjustable setting voltage signal (VH) and adjustable minimum setting voltage signal (VL) simultaneously simultaneously, can meet the demand of different motors and applicable to different application occasion, to increase the flexibility ratio of motor applications.But, for fear of motor rotary speed is low, stop operating afterwards to a certain degree and in order effectively to regulate temperature, the function that can set by minimum speed, controls motor and keep the requirement of minimum heat radiation and take into account energy-conservation effectiveness.

Refer to Figure 10 A, Figure 10 A is the waveform schematic diagram of setting for the additional minimum speed of the third embodiment of the present invention.Clearly, difference between Figure 10 A and Fig. 9 A is only: Figure 10 A has configured an adjustable minimum speed setting voltage signal (ALG) in three kinds of state ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3V, VL=2V), CASE2 (VH=5V, VL=0V), itself and the analog signal (VTH) producing after conversion formula conversion are together compared with triangular signal (TRI), determine that according to this its output speed is than (Duty%).As shown in Figure 10 A, suppose under the state of ORG, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, adjustable minimum setting voltage signal (VL) is made as to 1.25V, the highest adjustable setting voltage signal (VH) is made as 3.75V, and additional adjustable minimum speed setting voltage signal (ALG) is made as to 2V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 1.25V to 3.75V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the ORG oscillogram of Figure 10 A, refer to the ORG oscillogram of Figure 10 A the explanation according to the ORG oscillogram of Fig. 9 A, because the result of analog signal (VTH) is consistent with high voltage and the low-voltage of triangular signal (TRI), can between 1.25V to 3.75V, change, but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change.Secondly, suppose under the state of CASE1, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 3V, adjustable minimum setting voltage signal (VL) is made as 2V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 2.25V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 2V to 3V, the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE1 oscillogram of Figure 10 A, refer to the CASE1 oscillogram of Figure 10 A the explanation according to the CASE1 oscillogram of Fig. 9 A, when being 2V, analog signal (VTH) contacts with triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, and current potential now can be higher than the low-voltage 1.25V of triangular signal (TRI), thereby institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 1.25V under ORG state than (Duty%), moreover to turn to 3V low compared with the high voltage 3.75V of triangular signal (TRI) due to the hypermutation of analog signal (VTH), thereby institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 2.25V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change, again secondly, suppose under the state of CASE2, the high voltage of its triangular signal (TRI) is fixed as 3.75V, low-voltage is fixed as 1.25V, the highest adjustable setting voltage signal (VH) is made as to 5V, adjustable minimum setting voltage signal (VL) is made as 0V, and additional adjustable minimum speed setting voltage signal (ALG) is changed and is made as 1.75V, the result of the analog signal (VTH) producing after conversion formula conversion can change between 0V to 5V, by the high voltage of itself and triangular signal (TRI) and low-voltage relatively and observe its output speed than (Duty%), the high voltage of itself and triangular signal (TRI) and low-voltage and additional adjustable minimum speed setting voltage signal (ALG) are together compared, and observe its output speed than (Duty%), the result producing is as the CASE2 oscillogram of Figure 10 A, refer to the CASE2 oscillogram of Figure 10 A the explanation according to the CASE2 oscillogram of Fig. 9 A, because analog signal (VTH) is to be started to change by 0V, when being 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 1.75V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can according to adjustable minimum speed setting voltage signal (ALG) with output speed than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), can be by its analog signal (VTH) and triangular signal (TRI) relatively with output speed than (Duty%), its result can be a linear change.

Afterwards, by ORG (VH=3.75V, VL=1.25V), CASE1 (VH=3V, VL=2V), CASE2 (VH=5V, VL=0V) output speed of these three kinds of states converts speed curves according to its work period of control signal (that is pwm signal) than (Duty cycle) than (Duty%), refer to Figure 10 B and coordinate Figure 10 A, as shown in Figure 10 B, the speed curves figure setting for the additional minimum speed of the third embodiment of the present invention, transverse axis is to be control signal (that is pwm signal) its work period (Dutycycle%), the longitudinal axis is for motor output speed is than (Duty%), observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under ORG state, according to described in Figure 10 A and coordinate Figure 10 B, the result of analog signal (VTH) can be consistent with high voltage and the low-voltage of triangular signal (TRI), but arrange after adjustable minimum speed setting voltage signal (ALG) 2V, make motor may operate in minimum speed, therefore when analog signal (VTH) is less than the current potential 2V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 30% than (Duty%), that is between work period (Duty cycle) in 0% to 30%, its output speed can maintain 30% than (Duty%), when analog signal (VTH) is greater than after the current potential 2V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Dutycycle) be 30% after), its output speed can be a linear change than (Duty%) result.Then, observe the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE1 state, according to described in Figure 10 A and coordinate 10B, when being 2V, analog signal (VTH) contacts with triangular signal (TRI), therefore in having output speed than (Duty%) at the very start, and current potential now can be higher than the low-voltage 1.25V of triangular signal (TRI), thereby institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 1.25V under ORG state than (Duty%), moreover to turn to 3V low compared with the high voltage 3.75V of triangular signal (TRI) due to the hypermutation of analog signal (VTH), thereby institute's output speed can be less than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 2.25V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 2.25V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 20% than (Duty%), that is between work period (Duty cycle) in 0% to 25%, its output speed can maintain 20% than (Duty%), when analog signal (VTH) is greater than after the current potential 1.3V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 25% after), its output speed can be a linear change than (Duty%) result, observe again the speed curves variation by 0% to 100% in the work period (Duty cycle) under its CASE2 state, according to described in Figure 10 A and coordinate Figure 10 B, because analog signal (VTH) is to be started to change by 0V, when being 1.25V, analog signal (VTH) just can contact with triangular signal (TRI), now just start to have output speed than (Duty%), but due to the hypermutation of analog signal (VTH), to turn to 5V high compared with the high voltage 3.75V of triangular signal (TRI), therefore institute's output speed can be larger than (Duty%) than the output speed when analog signal (VTH) is 3.75V under ORG state than (Duty%), but arrange after adjustable minimum speed setting voltage signal (ALG) 1.75V, make motor may operate in minimum speed to meet the requirement of the minimum heat radiation of motor, therefore when analog signal (VTH) is less than the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG), output speed can maintain 40% than (Duty%), that is between the work period (Dutycycle) in 0% to 35%, its output speed can maintain 40% than (Duty%), when analog signal (VTH) is greater than after the current potential 1.75V of adjustable minimum speed setting voltage signal (ALG) (that is work period (Duty cycle) be 35% after), its output speed can be a linear change than (Duty%) result.Comprehensively the above, can, in order to remain motor operated in minimum speed, also can adjust in response to different motors and different system demand after the additional minimum speed setting of the 3rd embodiment.

Finally, referring to Figure 11, is to be motor driving method flow chart of the present invention.As shown in figure 11, motor driving method is to comprise following steps:

Step 1100: a PWM change-over circuit is provided, its PWM change-over circuit has a first input end, one second input, one the 3rd input and an output, wherein first input end is connected with a pwm signal, the second input is connected with the highest adjustable setting voltage signal (VH), the 3rd input is connected with an adjustable minimum setting voltage signal (VL), and export an analog signal (VTH) by output, wherein by adjusting pwm signal, the highest adjustable setting voltage signal (VH) or adjustable minimum setting voltage signal (VL) can change analog signal (VTH), then enter step 1101.

Step 1101 a: oscillating circuit is provided; Its oscillating circuit is to produce a triangular signal, and triangular signal can be adjusted between a high voltage level and a low-voltage level, then enters step 1102.

Step 1102 a: comparator is provided; Its comparator has a first input end, one second input, one the 3rd input and an output, the triangular signal that wherein first input end produces with oscillating circuit is connected, the second input is connected with the analog signal that PWM change-over circuit is exported, the 3rd input receives an adjustable minimum speed setting voltage signal, and produce a driving signal (S_DR) by output output, finally enter step 1103.

Step 1103 a: control unit is provided; Its control unit is to receive driving signal that comparator produces to control a motor.

Although the present invention discloses as above with aforesaid preferred embodiment; so it is not in order to limit the present invention; anyly have the knack of alike operator; without departing from the spirit and scope of the present invention; when doing a little change and retouching, what therefore scope of patent protection of the present invention must define depending on the appended claim scope of this specification is as the criterion.

Claims

1. there is the motor drive that minimum speed is set, comprising:

One PWM change-over circuit, there is a first input end, one second input, one the 3rd input and an output, wherein this first input end is connected with a control signal, this second input is connected with the highest adjustable setting voltage signal, the 3rd input is connected with an adjustable minimum setting voltage signal, and export an analog signal by this output, wherein, this analog signal can be by adjusting this control signal, this is adjustable, and the highest setting voltage signal or this adjustable minimum setting voltage signal change;

One oscillating circuit, in order to produce a triangular signal; And

One comparator, there is a first input end, one second input, one the 3rd input and an output, this triangular signal that wherein this first input end produces with this oscillating circuit is connected, this second input is connected with this analog signal that this PWM change-over circuit is exported, the 3rd input receives an adjustable minimum speed setting voltage signal, and drives signal by this output output one.

2. the motor drive with minimum speed setting according to claim 1, it further comprises a control unit, in order to receive this driving signal to control a motor.

3. the motor drive with minimum speed setting according to claim 1, wherein this PWM change-over circuit further comprises:

One first operational amplifier, has a positive input terminal and be electrically connected at this highest adjustable setting voltage signal, a negative input end, and an output is electrically connected at this negative input end;

One second operational amplifier, has a positive input terminal and be electrically connected at this adjustable minimum setting voltage signal, a negative input end, and an output is electrically connected at this negative input end;

One first switch element, have receive an input of one first input signal be coupled to this first operational amplifier, be coupled to an output node an output, be coupled to a control end of this control signal and be coupled to a link of a common node, whether this first switch element determines this first input signal of conducting according to this control signal;

One second switch element, have receive an input of one second input signal be coupled to this second operational amplifier, be coupled to this output node an output, be coupled to a control end of this control signal and be coupled to a link of this common node, whether this second switch element determines this second input signal of conducting according to this control signal;

One inverter, have an input in order to receive this control signal, and an output is connected in this common node; And

One low-pass filter circuit, it becomes this analog signal in order to the voltage transitions that this first node is produced.

4. the motor drive with minimum speed setting according to claim 1, wherein this control signal is a pwm signal.

5. the motor drive with minimum speed setting according to claim 1, wherein this triangular signal is adjusted between a high voltage level and a low-voltage level.

6. the motor drive with minimum speed setting according to claim 2, wherein this motor is a single-phase motor.

7. the motor drive with minimum speed setting according to claim 2, wherein this motor is a three-phase motor.

8. the motor drive with minimum speed setting according to claim 3, wherein this first switch element and this second switch element are a transmission lock.

9. the motor drive with minimum speed setting according to claim 3, wherein this low-pass filter circuit further comprises:

One first resistance, has a first end, is coupled to this first node, and one second end;

One second resistance, has a first end, is coupled to this second end of this first resistance, and one second end;

One first electric capacity, has a first end, is coupled to this second resistance, and one second end is coupled to earth terminal;

One the 3rd operational amplifier, has a positive input terminal and is electrically connected at contact, the negative input end between this second resistance and this first electric capacity, and an output is electrically connected at this negative input end, in order to export this analog signal; And

One second electric capacity, has a first end, be coupled to the contact between this first resistance and this second resistance, and one second end is coupled to the output of the 3rd operational amplifier.

10. the motor drive with minimum speed setting according to claim 9, wherein this low-pass filter circuit is a second-order low-pass filter circuit.

11. 1 kinds have the motor driving method that minimum speed is set, comprising:

One PWM change-over circuit is provided, it has a first input end, one second input, one the 3rd input and an output, wherein this first input end is connected with a pwm signal, this second input is connected with the highest adjustable setting voltage signal, the 3rd input is connected with an adjustable minimum setting voltage signal, and exports an analog signal by this output;

Provide an oscillating circuit, in order to produce a triangular signal; And

One comparator is provided, it has a first input end, one second input, one the 3rd input and an output, this triangular signal that wherein this first input end produces with this oscillating circuit is connected, this second input is connected with this analog signal that this PWM change-over circuit is exported, the 3rd input receives an adjustable minimum speed setting voltage signal, and drives signal by this output output one.

Wherein, by adjusting this pwm signal, this is adjustable the highest setting voltage signal or this adjustable minimum setting voltage signal change this analog signal.

The 12. motor driving methods with minimum speed setting according to claim 11, it further comprises provides a control unit, in order to receive this driving signal to control a motor.

The 13. motor driving methods with minimum speed setting according to claim 11, wherein this PWM change-over circuit further comprises:

One first switch element, have receive an input of one first input signal be coupled to this first operational amplifier, be coupled to a first node an output, be coupled to a control end of this control signal and be coupled to a link of a common node, whether this first switch element determines this first input signal of conducting according to this control signal;

One second switch element, have receive an input of one second input signal be coupled to this second operational amplifier, be coupled to this first node an output, be coupled to a control end of this control signal and be coupled to a link of this common node, whether this second switch element determines this second input signal of conducting according to this control signal;

One inverter, having an input is to receive this control signal, and an output is connected in this common node; And

One low-pass filter circuit, it is that a voltage transitions in order to this first node is produced becomes this analog signal.

The 14. motor driving methods with minimum speed setting according to claim 11, wherein this triangular signal is adjusted between a high voltage level and a low-voltage level.

The 15. motor driving methods with minimum speed setting according to claim 12, wherein this motor is a single-phase motor.

The 16. motor driving methods with minimum speed setting according to claim 12, wherein this motor is a three-phase motor.

The 17. motor driving methods with minimum speed setting according to claim 13, wherein this first switch element and this second switch element are a transmission lock.

The 18. motor driving methods with minimum speed setting according to claim 13, wherein this low-pass filter circuit further comprises:

One first resistance, has a first end, is coupled to this this first node, and one second end;

The 19. motor driving methods with minimum speed setting according to claim 18, wherein this low-pass filter circuit is a second-order low-pass filter circuit.