TWI579576B - Alternating current detecting apparatus - Google Patents

Description

AC power detection device

The present invention relates to a detecting device, and more particularly to an AC power detecting device.

A power supply device or a power supply system is a common electronic device for providing power to a target device (such as a computer, home appliance, etc.) to drive the target device. In general, a normal AC power supply has a voltage range of 90 volts to 264 volts. If the voltage supplied by the power system is unstable, such as below 90 volts, it may cause abnormal operation or damage to the target device. Therefore, in order to solve this problem, it is common to provide a power detection line between the power system and the target device.

Please refer to FIG. 1. FIG. 1 is a schematic diagram showing the circuit structure of a conventional AC power detecting device. The AC power detecting device 100 is mainly composed of a voltage dividing unit 110, a switch 120, an optical coupling unit 130, and a detecting component 140. The voltage dividing unit 110 includes three resistors 111, 112, 113 connected in series, one end of which receives the input voltage Vin and the other end of which is coupled to the reference ground 151. The switch 120 is configured to control the ON/OFF state according to the voltage division level provided by the voltage dividing unit 110, thereby controlling the current flowing through the LEDs 131 of the optical coupling unit 130. The photocoupler element 132 of the optical coupling unit 130 is configured to control the on/off state of the current through the light emitting diode 131 to control the voltage level of the output to the detecting component 140. Detection component 140 It is used to control the output level of the light source element 132 according to its voltage level. Further, the photocoupler element 132 is coupled to the ground 152 via a resistor 135.

When the AC power supply 101 is suddenly powered off or the voltage is unstable, that is, when the input voltage Vin changes from a high level (High) to a low level (Low), the voltage dividing unit 110 is provided to the control end of the switch 120 at this time. The voltage dividing level will also change from the high level to the low level, and then the switch 120 will become the off state, and the voltage level flowing through the photocoupler element 132 will also change from the high level to the low level, thereby When the input voltage level of the detecting component 140 changes from the high level to the low level, it can be known that the power supply is abnormal.

However, according to the conventional AC power detecting device 100 of FIG. 1, when the AC power supply 101 is suddenly powered off, since the capacitor 105 also stores electric charge, the detecting element 140 must wait until the capacitor 105 is discharged. The AC power supply 101 has a power outage condition, which makes it impossible to immediately notify the microcontroller 150 to perform a corresponding emergency processing operation. In other words, the conventional AC power detecting device 100 does not have an instant detection mechanism and must wait until the capacitor 105 is discharged. Furthermore, according to the AC power detecting device 100 of FIG. 1, since the number of electronic components used is large and the circuit structure is complicated, the cost is relatively high.

Therefore, the present invention provides an AC power detecting device, which has the advantages of immediate detection and cost reduction.

The object of the present invention is to provide an AC power detecting device including a first ground end, a second ground end, a voltage dividing unit and a first resistor. The first ground has an alternating voltage. The second ground has a ground voltage, wherein there is a voltage difference between the second ground and the first ground. Partition unit Connected between the first ground end and the second ground end for generating an alternating voltage component according to the alternating voltage to the output end of the voltage dividing unit. The first resistor is electrically connected between the output end of the voltage dividing unit and the second ground end.

The AC power detecting device according to the present invention transmits the voltage dividing characteristic of the voltage dividing unit and directly discharges through the first resistor, and not only has the power supply condition for instantly detecting the AC power supply, but also has a power saving effect.

Additional features and advantages of the invention will be set forth in the description in the description. Other objects and advantages of the present invention will be realized and attained by the description of the appended claims.

100,200,400‧‧‧AC power detection device

101,301‧‧‧AC power supply

102,302‧‧‧Rectifier circuit

105,303,432‧‧‧ capacitor

110,210,215‧‧ ‧pressure unit

111,112,113,135,216,217,220,335,433‧‧‧Resistors

120,325‧‧‧ switch

130‧‧‧Optical coupling unit

131‧‧‧Lighting diode

132‧‧‧Photocouple components

140‧‧‧Detection components

151, 351 ‧ ‧ primary side ground

150,250,350‧‧‧Microcontrollers

152,352‧‧‧second side ground

160,260,360‧‧‧ target device

251‧‧‧ first ground

252‧‧‧Second ground

300‧‧‧Power system

320‧‧‧Transformers

321‧‧‧Primary winding

322‧‧‧Secondary winding

323‧‧‧Auxiliary winding

330‧‧‧Switch control circuit

340‧‧‧ Feedback circuit

370‧‧‧First rectification filter circuit

380‧‧‧Second rectification filter circuit

430‧‧‧Rectifier unit

431‧‧‧dipole

1 is a schematic diagram showing the circuit structure of a conventional AC power detecting device; FIG. 2A is a schematic diagram showing the circuit structure of an AC power detecting device according to a first preferred embodiment of the present invention; FIG. 2B is a view showing the present invention. FIG. 3 is a schematic diagram showing the circuit structure of an AC power detecting device according to a preferred embodiment of the present invention; and FIG. 4 is a view showing another preferred embodiment of the present invention. A schematic diagram of the circuit structure of the AC power detecting device of the embodiment.

2A and FIG. 3, FIG. 2A is a schematic diagram showing the circuit structure of the AC power detecting device according to the first preferred embodiment of the present invention, and FIG. 3 is a circuit diagram showing the power system of the preferred embodiment of the present invention. Schematic.

As shown in FIG. 2A, the AC power detecting device 200 of the present invention includes a voltage dividing unit 210 and a resistor 220. The voltage dividing unit 210 is electrically connected between the first ground end 251 and the second ground end 252 for generating an AC voltage dividing voltage V _DIV from the output end of the voltage dividing unit 210 according to the AC voltage Vac from the first ground end 251. The resistor 220 is electrically connected between the output end of the voltage dividing unit 210 and the second ground end 252. In this embodiment, the first ground end 251 is coupled to the primary side ground end (reference ground) 351 of the power system 300 as shown in FIG. 3, and the second ground end 252 is coupled to FIG. The secondary side ground (earth) 352 of the power system 300, wherein the first ground end 251 has an alternating voltage Vac, the second ground end 252 has a ground voltage GND, and between the first ground end 251 and the second ground end 252 Has a voltage difference.

In this embodiment, as shown in FIG. 2A, the voltage dividing unit 210 is preferably formed by connecting at least two capacitors 211 and a capacitor 212 in series, and the two capacitors 211 and 212 are coupled to the first ground end 251 and Between the second ground ends 252, wherein the AC divided voltage V _DIV is generated by the capacitor 211 and the divided output point P1 of the capacitor 212. In addition, the capacitance values of the capacitor 211 and the capacitor 212 can be designed to be the same or different, in other words, the capacitance value of the capacitor 211 and the capacitor 212 can be adjusted to obtain the desired AC voltage division V _DIV .

In the preferred embodiment of FIG. 2A, the voltage dividing unit 210 is formed by connecting at least two capacitors 211 and the capacitor 212 in series. However, the voltage dividing unit 210 may be composed of other electronic components, as long as it can Provide AC partial voltage V _DIV . As shown in FIG. 2B, FIG. 2B is a schematic diagram showing the circuit structure of an AC power detecting device according to a second preferred embodiment of the present invention. The difference between the second embodiment and the first embodiment is that the voltage dividing unit 215 of the AC power detecting device 200 of the second embodiment replaces the first embodiment with at least two resistors 216 and resistors 217 connected in series. The capacitor 211 and the capacitor 212, wherein the AC divided voltage V _DIV is generated by the resistor 216 and the divided output point P2 of the resistor 217. Similarly, the resistance values of the resistor 216 and the resistor 217 can be designed to be the same or different, that is, the resistance value of the resistor 216 and the resistor 217 can be adjusted to obtain the desired AC voltage division V _DIV .

3 shows a power supply system 300 in accordance with a preferred embodiment of the present invention for use with the AC power detection device of the present invention. As shown in FIG. 3, the power system 300 includes an AC power supply 301, a rectifier circuit 302, a capacitor 303, a transformer 320, a switch 325, a switch control circuit 330, a feedback circuit 340, a first rectification filter circuit 370, and a second rectification filter circuit. 380. The rectifier circuit 302 and the capacitor 303 are configured to perform a rectification filtering process on the AC input voltage Vac provided by the AC power supply 301 to generate an input voltage Vin, and one end thereof is coupled to the primary side ground end 351, respectively. The transformer 320 includes a primary winding 321, a secondary winding 322, and an auxiliary winding 323, wherein the primary winding 321 is for receiving an input voltage Vin. The positive output end of the first rectifying and filtering circuit 370 is coupled to the feedback circuit 340, and the negative output end is coupled to the secondary side ground end 352. The first rectifying and filtering circuit 370 is used to sense the pre-output voltage Vop of the secondary winding 322. A rectification filtering process is performed to generate an output voltage Vout and feed it to the feedback circuit 340. The feedback circuit 340 generates a feedback signal Sfb according to the output voltage Vout and feeds it back to the switch control circuit 330. The second rectification filter circuit 380 is configured to perform a rectification filtering process on the induced voltage of the auxiliary winding 323 to generate a supply voltage Vcc to the switch control circuit 330. The switch control circuit 330 generates a control signal Sc according to the feedback signal Sfb to control the on/off state of the switch 325, thereby controlling the current flowing through the primary winding 321. Further, the switch 325 is coupled to the primary side ground end 351 via a resistor 335. In short, the primary side ground end 351 refers to the power supply system 300. The ground input end of the voltage input side (such as the voltage input end of the transformer 320 of FIG. 3), and the secondary side ground end 352 refers to the grounding of the voltage output side of the power supply system 300 (such as the voltage output end of the transformer 320 of FIG. 3). end.

Referring to FIG. 2A and FIG. 3, the first ground end 251 is coupled to the primary side ground end 351 of the power system 300 as shown in FIG. 3, and the second ground end 252 is coupled to the ground end 252 as shown in FIG. The secondary side ground 352 of the power system 300, so the voltage value of the first ground end 251 varies with the AC voltage Vac, and the second ground end 252 is coupled to the ground so that its voltage value is 0 volt, so that the first A voltage difference is maintained between the ground terminal 251 and the second ground terminal 252. Further, in the present embodiment, the microcontroller 250 is a microcontroller that can handle the AC divided voltage V _DIV .

As shown in FIG. 2A, in operation, when the AC voltage Vac from the first ground terminal 251 changes from the high level to the low level, the AC voltage divider V _DIV output by the voltage dividing unit 210 also changes from a high level. Low level. Then, after the microcontroller 250 detects that the power-off situation may occur at this time according to the voltage level change of the AC voltage divider V _DIV , the microcontroller 250 immediately notifies the target device 260 of the back end to perform the corresponding emergency processing operation to avoid the cause. The power failure causes damage to the target device 260 or loss of data.

It can be seen from the above that the AC power detecting device 200 of the present invention does not have the capacitor 105 of the conventional AC power detecting device 100, but is directly discharged through the resistor 220, so that the AC power supply 101 can be immediately powered off. The situation is immediately notified to the target device 260 to perform a corresponding emergency processing operation. In addition, compared with the conventional AC power detecting device 100, the AC power detecting device 200 of the present invention not only has an instant detection mechanism, but also has a power saving effect.

Please refer to FIG. 4. FIG. 4 is a schematic diagram showing the circuit structure of an AC power detecting device according to another preferred embodiment of the present invention. As shown in FIG. 4, the difference from the foregoing preferred embodiment is that the AC power detecting device 400 of the present embodiment adds a rectifying unit 430. Further, in the present embodiment, the microcontroller 350 is a microcontroller that can process the DC voltage V _DC .

The rectifying unit 430 is electrically connected between the output end of the voltage dividing unit 210 and the second ground end 252 for receiving the AC divided voltage V _DIV and converting the AC divided voltage V _DIV into a DC voltage V _DC . The rectifying unit 430 is preferably composed of a diode 431, a capacitor 432 and a resistor 433. The input end of the diode 431 is coupled to one end of the resistor 220 to receive the AC divided voltage V _DIV , and the output end of the diode 431 is electrically connected to the microcontroller 350. The capacitor 432 is connected in parallel with the resistor 433 and coupled between the output end of the diode 431 and the other end of the resistor 220.

As shown in FIG. 4, in operation, when the AC voltage Vac from the first ground terminal 251 changes from the high level to the low level, the AC voltage divider V _DIV output by the voltage dividing unit 210 also changes from a high level. The low level is caused to cause the DC voltage V _DC output from the rectifying unit 430 to change from a high level to a low level. When the microcontroller 350 receives the DC voltage V _DC from the high level to the low level, the microcontroller 350 determines that a power outage situation may occur at this time and immediately notifies the target device 360 of the back end to perform the corresponding emergency processing operation. In order to avoid damage to the target device 360 or loss of data due to power failure.

In summary, the AC power detecting device of the present invention transmits the voltage dividing characteristic of the voltage dividing unit, for example, using at least two capacitors or a series voltage dividing characteristic of the resistor, and can be connected from the first ground end (primary side ground end) The voltage dividing output point of the second ground end (secondary ground end) generates an alternating current signal, and then the microcontroller immediately determines whether a power outage occurs, thereby controlling the target device to immediately perform an emergency processing operation.

Various modifications and changes may be made to the remote server management method and related apparatus of the present invention without departing from the spirit and scope of the invention. Therefore, various modifications and changes are intended to be included within the scope of the invention.

200‧‧‧AC power detection device

210‧‧‧Dividing unit

211,212‧‧‧ capacitor

220‧‧‧Resistors

250‧‧‧Microcontroller

251‧‧‧ first ground

252‧‧‧Second ground

260‧‧‧ Target device

Claims (7)

An AC power detecting device includes: a first ground end having an alternating current voltage; and a second ground end having a ground voltage, wherein the second ground end and the first ground end have a voltage difference; And a voltage dividing unit having a first capacitor and a second capacitor, wherein the first capacitor is electrically connected to the first ground, the second capacitor is electrically connected to the second ground, and one of the voltage dividing units outputs The terminal is disposed between the first capacitor and the second capacitor and generates a voltage dividing signal according to the alternating voltage, and determines whether the alternating voltage is powered off according to the voltage dividing signal. The AC power detecting device of claim 1, further comprising a first resistor electrically connected between the output end of the voltage dividing unit and the second ground end. The AC power detecting device of claim 1, wherein the first ground end is coupled to one of the primary side ends of the power system, and the second ground end is coupled to one of the secondary sides of the power system. At the ground end, the power system includes: an AC power supply for providing an AC input voltage; a rectifying circuit for performing rectification processing on the AC input voltage; and a capacitor for performing filtering processing on the AC input voltage And generating an input voltage; a transformer comprising a primary winding, a primary winding and an auxiliary winding, wherein the primary winding is for receiving the input voltage; and a switch is coupled between the primary winding and the primary side ground a first rectifying and filtering circuit coupled to the secondary side ground for sensing the secondary winding a pre-output voltage is subjected to rectification filtering processing to generate an output voltage; a second rectification filtering circuit is configured to perform rectification filtering processing on the induced voltage of the auxiliary winding to generate a power supply voltage; and a feedback circuit for The output voltage generates a feedback signal; and a switch control circuit is configured to receive the power supply voltage and generate a control signal according to the feedback signal to control an on/off state of the switch. The AC power detecting device of claim 2, further comprising a rectifying unit electrically connected between the output end of the voltage dividing unit and the second ground end for receiving the voltage dividing signal The divided voltage signal is converted to a DC voltage. The AC power detecting device of claim 4, wherein the rectifying unit comprises: a diode, the input end of which is coupled to the output end of the voltage dividing unit, and the output end of which is electrically connected to a microcontroller a capacitor coupled between the output end of the diode and the second ground; and a second resistor coupled in parallel with the capacitor and coupled to the output end of the diode Between the second ground. The AC power detecting device of claim 5, wherein the microcontroller is electrically connected to a target device, and the microcontroller is configured to control the target device to perform an emergency processing operation according to a voltage level of the DC voltage. . The AC power detecting device of claim 1, wherein the output end of the voltage dividing unit is electrically connected to a microcontroller, and the microcontroller is electrically connected to a target device, and the microcontroller is configured to use the One of the voltage levels of the pressure signal controls the target device to perform an emergency processing operation.