CN100488024C - current control device and method - Google Patents

Abstract

A current control device is used for a fan motor and comprises a current sampling module, a signal generating module, a current detection module and a current control module. The current sampling module measures the operating current of the fan motor to generate a sampling current signal, wherein the operating current is controlled according to a driving signal, the signal generating module generates a threshold current signal, the current detection module receives the sampling current signal and the threshold current signal and detects the sampling current signal according to the threshold current signal to generate a motor protection signal, and the current control module receives the motor protection signal and stops generating or reducing the driving signal according to the motor protection signal.

Description

Current control device and method

technical field

The invention relates to a current control device, in particular to a current control device for controlling motor current.

Background technique

Motors are widely used in fans or various electronic devices. However, if the operating current of the motor is too high for a long time, it is easy to be damaged.

As shown in FIG. 1 , the fan motor controller 11 generates driving currents 112 - 115 according to a speed control signal 111 . The fan motor 12 includes a coil 121 and several transistors 122-125, each of the driving currents 112-115 is input to each of the transistors 122-125 to control the operating current of the coil 121, and the input voltage V _cc is electrically connected to the transistors 122, 123 , one end of the coil 121 is electrically connected to the transistors 122 , 124 , and the other end of the coil 121 is electrically connected to the transistors 123 , 125 . The emitters of the transistors 124, 125 are electrically connected to the current sampler 13, and the current sampler 13 samples the magnitude of the emitter current of the transistors 124, 125, and the comparator 141 compares the sampling result of the current sampler 13 with the reference voltage V _ref In comparison, when the sampling current is too large, the two transistors 142 , 143 are enabled to adjust the driving current 114 , 115 and reduce the operating current of the coil 121 .

The operating current of the coil 121 can be reduced through the control of the transistors 142 , 143 , so as to avoid damage caused by the excessive operating current. However, the drive currents 114, 115 generated by the fan motor controller 11 have not decreased. When the transistors 142, 143 stop functioning, the operating current of the coil 121 will still be too large, so the operating current of the coil 121 will be too high. The big main cause is still not eliminated.

Therefore, the present application proposes a current control device in order to control the driving current of the driving motor, thereby avoiding excessive operating current of the motor due to improper control of the driving current, and prolonging the service life of the motor.

Contents of the invention

In view of the above problems, an object of the present invention is to propose a current control device capable of adjusting the operating current of a motor.

In order to achieve the above purpose, the current control device according to the present invention is used for a fan motor, and includes a current sampling module, a signal generating module, a current detecting module and a current controlling module. The current sampling module measures the operating current of the fan motor to generate a sampling current signal, wherein the operating current is controlled according to the driving signal, the signal generation module generates a threshold current signal, and the current detection module receives the sampling current signal and The threshold current signal is used to detect the sampling current signal according to the threshold current signal to generate a motor protection signal. The current control module receives the motor protection signal and stops generating or reduces the driving signal according to the motor protection signal.

In addition, the present invention also proposes a current control device. The current control device receives the sampling current signal of the fan motor module, and includes a signal generation module, a current detection module and a current control module, the signal generation module generates a threshold current signal, and the current detection module receives the sampling current signal and the threshold current signal, and detect the sampling current signal based on the threshold current signal to generate a motor protection signal, the current control module receives the motor protection signal, and stops generating or reducing the driving signal according to the motor protection signal, wherein the The driving signal controls the operation of the fan motor module.

In addition, the present invention also proposes a current control method for the fan motor. The current control method includes a current sampling step, a signal generation step, a current detection step and a current control step. The current sampling step measures the operating current of the fan motor to generate a sampling current signal, wherein the operating current is controlled according to the driving signal, the signal generating step generates a threshold current signal, and the current detecting step detects the sampling current according to the threshold current signal signal to generate a motor protection signal, and the current control step stops generating or reduces the driving signal according to the motor protection signal.

In summary, the current control device and method of the present invention detects the sampled current signal based on the threshold current signal to generate a motor protection signal, and stops generating or reduces the driving signal of the fan motor according to the motor protection signal, thereby reducing motor The situation where the operating current is in an excessive state to prolong the operating life of the motor.

Description of drawings

Fig. 1 shows the block diagram of the current controller of conventional fan motor;

Fig. 2 shows the block diagram of the current control device of the preferred embodiment of the present invention;

FIG. 3 shows a block diagram of the current detection module including a comparator in the current control device of the preferred embodiment of the present invention;

Fig. 4 shows the block diagram of the time control module including the delayer in the current control device of the preferred embodiment of the present invention;

FIG. 5 shows a block diagram of the time control module including two resistors in the current control device of the preferred embodiment of the present invention;

FIG. 6 shows a block diagram of a current control device including a voltage sampling module in a preferred embodiment of the present invention;

Figure 7 shows a current control device of a preferred embodiment of the present invention; and

Fig. 8 shows a flowchart of a current control method in a preferred embodiment of the present invention.

Description of component symbols:

11: Fan motor controller 111: Speed control signal

112～115: drive current 12: fan motor

121: Coil 122～125, 142, 143: Transistor

13: Current sampler 141: Comparator

V _cc : Input voltage V _ref : Reference voltage

2: Current control device 21: Current sampling module

22, 41: Signal generating module 221: The first resistor

222: Second resistor 23, 42: Current detection module

231: Comparator 24, 43: Current control module

25: Time Control Module 251: Delay

252: Logic gate 26: Time control module

261～262: Resistor 263: Diode

264: Capacitor 27: Voltage sampling module

3: Fan motor 4: Current control device

5: Fan motor module S ₂₁ , S ₅₁ : Sampling current signal

S ₂₂ , S ₄₁ : Threshold current signal S ₂₃ , S ₄₂ : Motor protection signal

S ₂₄ , S ₄₃ : Drive signal S ₂₅ : Delay signal

S ₂₆ : Sampling voltage signal S ₂₇ : Threshold voltage signal

S ₃₁ : Operating current S ₃₂ : Operating voltage

EN: enable pin V: power supply

Step1～Step4: Steps of the current control method

Detailed ways

The current control device and method according to preferred embodiments of the present invention will be described below with reference to related drawings.

As shown in FIG. 2 , the current control device 2 of the preferred embodiment of the present invention is used for a fan motor 3 . The current control device 2 includes a current sampling module 21 , a signal generation module 22 , a current detection module 23 and a current control module 24 .

The current sampling module 21 measures the operating current S ₃₁ of the fan motor 3 to generate a sampling current signal S ₂₁ , wherein the operating current S ₃₁ is controlled according to the driving signal S ₂₄ , and the signal generating module 22 generates a threshold current signal S ₂₂ , the current detection module 23 receives the sampling current signal S ₂₁ and the threshold current signal S ₂₂ , and detects the sampling current signal S ₂₁ according to the threshold current signal S ₂₂ to generate a motor protection signal S ₂₃ , the current control module The group 24 receives the motor protection signal S ₂₃ , and stops generating or reduces the driving signal S ₂₄ according to the motor protection signal S ₂₃ , thereby reducing the operating current S ₃₁ .

The threshold current signal _S22 is set as the current upper limit of the operating current _S31 , and the current detection module 23 judges the operating current S of the fan motor ₃ by comparing the sampling current signal _S21 with the threshold current signal S22 ₃₁ whether it exceeds the current set by the threshold current signal _S22 , if the operating current _S31 is greater than the current upper limit set by the threshold current signal _S22 , the current detection module 23 generates the motor protection signal _S23 To prompt the current control module 24 to stop generating or reduce the driving signal S ₂₄ , thereby reducing the operating current S ₃₁ .

In addition, in this embodiment, the current control module 24 can be a controller, the current control module 24 can be interrupted by the motor protection signal _S23 to execute the current control program, the current control program stops generating or reduces the driving Signal. In addition, the current detection module 23 and the current control module 24 can also be integrated in the same controller.

As shown in FIG. 3 , the signal generating module 22 includes a first resistor 221 and a second resistor 222 . One end of the first resistor 221 is grounded, and the other end is connected in series with one end of the second resistor 222 . The other end of the second resistor 222 receives the power V to generate the threshold current signal S ₂₂ .

The current detection module 23 includes a comparator 231 . The comparator 231 receives the sampled current signal S ₂₁ and the threshold current signal S ₂₂ , and generates the motor protection signal _{S 23 according} to the threshold current signal S ₂₂ and the sampled current signal S 21 , wherein the comparator 231 is an amplifier.

As shown in FIG. 4 and FIG. 5 , in this embodiment, the current control module 24 can be a controller. The motor protection signal is input to the enable pin EN of the controller 24 , thus, the controller 24 is enabled according to the motor protection signal S ₂₃ . Therefore, when the operating current _S31 is not greater than the current upper limit set by the threshold current signal _S22 , the motor protection signal _S23 is set to a high level to enable the current control module 24, if the operating current When S ₃₁ is greater than the current upper limit corresponding to or set by the threshold current signal S ₂₂ , the current control module 24 is disabled to stop generating the driving signal S ₂₄ .

In order to effectively stop generating the driving signal S ₂₄ and reduce the operating current S ₃₁ , the current control device 2 may include a time control module. The time control module controls the off time of the current control module 24 to control the period during which the current control module 24 stops generating the driving signal S ₂₄ . During this period, developers or users can find or eliminate factors that cause the operating current S ₃₁ to be too large.

As shown in FIG. 4 , the current control device 2 may include a time control module 25 , and the time control module 25 includes a delayer 251 and a logic gate 252 . The delayer 251 is electrically connected to the current detection module 23 to receive the motor protection signal _S23 and generates a delay signal _S25 , and the logic gate 252 is electrically connected to the current detection module 23 and the delayer 251 to receive the motor The protection signal S ₂₃ is connected with the delay signal S ₂₅ , and the effective time of enabling or disabling the motor protection signal S ₂₃ input to the current control module 24 is controlled according to the delay signal S ₂₅ . The delayer 251 can be a charging and discharging circuit or a flip-flop, such as a D-type flip-flop (D-Filp-Flop) or an RS-type flip-flop (RS-Flip-Flop), and the logic gate 252 can be an OR Gate (NOR gate). Therefore, the enabling period of the delay signal S ₂₅ can be extended by the delayer 251 , and the delay signal S ₂₅ can be extended by the logic gate 252 to extend the period of turning off the current control module 24 .

As shown in FIG. 5 , the time control module 26 includes two resistors 261 , 262 , a diode 263 and a capacitor 264 . One end of the diode 263 is connected in series with the resistor 261 , the capacitor 264 is connected in parallel with the resistor 262 , and the other end of the diode 263 is electrically connected to the capacitor 264 and the resistor 262 . The resistors 261 , 262 and the capacitor 264 can be properly designed to prolong or reduce the response time of the motor protection signal S ₂₃ , thereby controlling the period of enabling or disabling the current control module 24 .

As shown in FIG. 6 , the current control device 2 further includes a voltage sampling module 27 . The voltage sampling module 27 measures the operating voltage S ₃₂ of the fan motor 3 to generate a sampling voltage signal S ₂₆ . The signal generation module 22 generates a threshold voltage signal S ₂₇ , the current detection module 23 receives the sampled current signal S ₂₁ , the threshold current signal S ₂₂ , the sampled voltage signal S ₂₆ and the threshold voltage signal S ₂₇ , and according to The sampling current signal S ₂₁ , the threshold current signal S ₂₂ , the sampling voltage signal S ₂₆ and the threshold voltage signal S ₂₇ generate the motor protection signal S ₂₃ .

The threshold voltage signal S ₂₇ is set as a voltage upper limit of the operating voltage of the fan motor 3 . Therefore, the current detection module 23 can also compare the sampled voltage signal S ₂₆ with the threshold voltage signal S ₂₇ to determine whether the operating voltage of the fan motor 3 exceeds the upper voltage limit set by the threshold voltage signal S ₂₇ . If the operating voltage is greater than the upper voltage limit set by the threshold voltage signal _S27 , the current detection module 23 generates the motor protection signal _S23 to prompt the current control module 24 to stop generating or reduce the driving signal _S24 .

In addition, as shown in FIG. 7, the current control device 4 of the preferred embodiment of the present invention receives the sampling current signal _S51 of the fan motor module 5, wherein the sampling current signal _S51 samples the operating current of the fan motor module 5 to generate . The current control device 4 includes a signal generation module 41 , a current detection module 42 and a current control module 43 . The signal generation module 41 generates a threshold current signal S ₄₁ , the current detection module 42 receives the sampling current signal S ₅₁ and the threshold current signal S ₄₁ , and detects the sampling current signal S ₅₁ according to the threshold current signal S ₄₁ to Generating a motor protection signal S ₄₂ , the current control module 43 receives the motor protection signal S ₄₂ , and stops generating or reduces a driving signal S ₄₃ according to the motor protection signal S 42 , wherein the driving signal S ₄₃ controls the fan motor module 5 action.

When the sampled current signal _S51 is greater than the current corresponding to the threshold current signal _S41 , the current control module 43 is turned off to stop generating the driving signal _S43 .

In addition, the current control module 43 is interrupted by the motor protection signal S ₄₂ to execute the current control program. The current control program stops generating or reducing the driving signal _S43 , and can control the duration of the driving signal _S43 stopping or reducing. The user or developer can set the length of the duration to effectively reduce the fan motor. The operating current of the module 5 further protects the fan motor module 5 .

Since the fan motor module 5 of this embodiment can correspond to the fan motor 3 and the current sampling module 21 in the embodiments of FIGS. The module 42 and the current control module 43 can respectively correspond to the signal generation module 22 , the current detection module 23 and the current control module 24 of the foregoing embodiments. Corresponding components have the same functions and processing methods, so the current control device 4 of this embodiment will not be described again.

As shown in FIG. 8 , the current control method of the present invention includes Step 1 to Step 4 .

Step 1 measures the operating current of the fan motor to generate a sampled current signal, wherein the operating current is controlled according to the driving signal.

Step Step2 generates a threshold current signal.

Step 3 detects the sampled current signal according to the threshold current signal to generate a motor protection signal.

Step 4 stops generating or reduces the driving signal according to the motor protection signal.

Since the current control method of this embodiment can be applied to the current control device in the embodiments of FIGS. repeat.

In summary, the current control device and method according to the present invention detects the sampled current signal based on the threshold current signal to generate a motor protection signal, and stops generating or reduces the driving signal of the fan motor according to the motor protection signal, thereby reducing The operating current of the motor is in an excessive state to prolong the operating life of the motor.

The above description is for illustration only, not for limitation. Any equivalent modification or change without departing from the spirit and scope of the present invention shall be included in the claims.

Claims (21)

1. current control device receives the sampling current signal of fan electromotor, comprises:

Signal produces module, produces the threshold current signal;

The current detecting module receives this sampling current signal and this threshold current signal, and detects this sampling current signal to produce the electric motor protecting signal according to this threshold current signal;

The Current Control module receives this electric motor protecting signal, and stops to produce drive signal or lower this drive signal according to this electric motor protecting signal, and wherein this drive signal is controlled this fan electromotor action; And

The time control die set is electrically connected between this current detecting module and this Current Control module, to control this electric motor protecting signal activation time.

2. current control device as claimed in claim 1, wherein this current detecting module and this Current Control module are integrated in controller.

3. current control device as claimed in claim 1, wherein this Current Control module is a controller, and the activation according to this electric motor protecting signal.

4. current control device as claimed in claim 3, wherein this electric motor protecting signal is set to high levle with this Current Control module of activation.

5. current control device as claimed in claim 1, wherein when this sampling current signal during greater than the pairing electric current of this threshold current signal, this Current Control module is closed to stop to produce this drive signal.

6. current control device as claimed in claim 1, wherein to carry out the Current Control program, this Current Control program stops to produce or lowering this drive signal to this Current Control module by this electric motor protecting signal interruption.

7. current control device as claimed in claim 1, wherein this drive signal of Current Control program control duration of stopping or lowering.

8. current control device as claimed in claim 1 wherein should the time control die set comprise:

Delayer is electrically connected to receive this electric motor protecting signal and to produce inhibit signal with this current detecting module; And

The logic lock is electrically connected with this current detecting module and this delayer receiving this electric motor protecting signal and this inhibit signal, and inputs to according to this inhibit signal control the activation time of this electric motor protecting signal of this Current Control module.

9. current control device as claimed in claim 1 wherein should the time control die set comprise:

First resistor receives this electric motor protecting signal;

Diode, an end and this first resistor in series;

Second resistor; And

Capacitor, in parallel with this second resistor, and be electrically connected with the other end of this diode, to control the activation time of this electric motor protecting signal.

10. current control device as claimed in claim 1 also comprises:

The voltage sampling module, the operating voltage that measures this fan electromotor is to produce the sampling voltage signal.

11. current control device as claimed in claim 10; wherein this signal produces module and produces the threshold voltage signal; this current detecting module receives this sampling current signal, this threshold current signal, this sampling voltage signal and this threshold voltage signal, and this sampling current signal, this threshold current signal, this sampling voltage signal and this threshold voltage signal that are received according to this current detecting module are to produce this electric motor protecting signal.

12. current control device as claimed in claim 1, wherein signal generation module comprises:

First resistor, an end ground connection; And

Second resistor, one end and this first resistor in series, the other end receives a power supply to produce this threshold current signal.

13. current control device as claimed in claim 1, wherein this current detecting module comprises:

Comparator, one input end receive this sampling current signal, and another input receives this threshold current signal, and the output of this comparator produces this electric motor protecting signal according to this threshold current signal and this sampling current signal.

14. a current control method is used for fan electromotor, comprises:

The current sampling step, the operating current that measures this fan electromotor is to produce the sampling current signal, and wherein this operating current is controlled according to drive signal;

Signal produces step, produces the threshold current signal;

The current detecting step detects this sampling current signal to produce the electric motor protecting signal according to this threshold current signal;

The Current Control step stops to produce this drive signal or lowers this drive signal according to this electric motor protecting signal; And

The time controlled step is controlled this electric motor protecting signal activation time.

15. current control method as claimed in claim 14, wherein this current detecting step and this Current Control step are executed in controller.

16. current control method as claimed in claim 14, wherein this Current Control step system is executed in the Current Control module, and according to this electric motor protecting signal this Current Control module of activation, this Current Control module is a controller.

17. current control method as claimed in claim 16, wherein this electric motor protecting signal is set to high levle with activation Current Control module.

18. current control method as claimed in claim 16, wherein when this operating current during greater than the pairing electric current of this threshold current signal, the Current Control module is closed to stop to produce this drive signal.

19. current control method as claimed in claim 16, wherein this Current Control step is executed in controller, and this controller by this electric motor protecting signal interruption to carry out the Current Control program, this Current Control program stops to produce or lowering this drive signal.

20. current control method as claimed in claim 14 also comprises:

The voltage sampling step, the operating voltage that measures this fan electromotor is to produce the sampling voltage signal.

21. current control method as claimed in claim 20; wherein this signal produces step and produces the threshold voltage signal, and this sampling current signal that this current detecting step is received according to the current detecting module, this threshold current signal, this sampling voltage signal and this threshold voltage signal are to produce this electric motor protecting signal.

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