CN111812397A - Detection circuit and air purification device - Google Patents

Abstract

The invention discloses a detection circuit and an air purification device. The detection circuit comprises: a sampling circuit connected in series with one of two adjacent polar plates; a voltage detection circuit connected in parallel with the sampling circuit; the voltage detection circuit Used to detect the voltage across the sampling circuit. In this way, during the long-term use of the air purification device, since the dust and impurities on the pole plates will increase, the relative distance between the two adjacent pole plates will be shortened, and the distance between the pole plates will be too close, which will cause The current flowing through the sampling circuit will become larger, so that the voltage collected by the voltage detection circuit will become larger. Thereby, the user can know the actual working condition of the air purification device in time.

Description

A detection circuit and air purification device

technical field

The invention relates to the technical field of household appliances, in particular to a detection circuit and an air purification device.

Background technique

With the improvement of people's living standards, many smart appliances have entered people's lives, and air purifiers are one of the types of people's daily use.

In the prior art, air purifiers usually kill germs in the air by means of high-voltage discharge between the plates. However, in the process of long-term use, the dust and impurities in the air will gradually accumulate on the plates, which will shorten the relative distance between the plates.

If the relative distance between the plates is shortened, and the high voltage between the plates of the air purifier is not changed, once the distance between the plates is too close, the electric field strength between the plates will increase, and the electric field will flow through the plates where the plates are located. The current of the circuit becomes larger, which seriously affects the service life of the product. And if the user does not know about it at this time, there will be a certain dangerous situation.

SUMMARY OF THE INVENTION

Therefore, the technical problem to be solved by the present invention is that the dust and impurities in the air existing in the prior art will gradually accumulate on the pole plate, so that the electric field intensity between the pole plates becomes larger, and the current flowing through the circuit where the pole plate is located changes. It will seriously affect the service life of the product, and if the user is not aware of it at this time, there will be a problem of dangerous situations. Thus, a detection circuit and an air purification device are provided.

In order to achieve the above purpose, an embodiment of the present invention provides a detection circuit, the detection circuit includes: a sampling circuit, connected in series with one of two adjacent electrode plates; a voltage detection circuit, connected in parallel with the sampling circuit; the voltage The detection circuit is used for detecting the voltage across the sampling circuit.

Optionally, the electrode plate includes a first electrode plate and a second electrode plate that are arranged adjacently; the sampling circuit includes a first sampling resistor, and the first sampling resistor is connected in series with the first electrode plate, or with the first electrode plate. The second plates are connected in series.

Optionally, the detection circuit further includes: a first switch, the first switch is connected in series with the first pole plate or in series with the second pole plate.

Optionally, the pole plate further includes a third pole plate and a fourth pole plate arranged adjacently; the sampling circuit further includes a second sampling resistor, and the second sampling resistor is connected in series with the third pole plate, or in series with the fourth plate.

Optionally, the detection circuit further includes: a second switch, the second switch is connected in series with the third electrode plate, or is connected in series with the fourth electrode plate.

The present invention also provides an air purification device, which includes: any one of the detection circuits; a power supply circuit, which is connected to the detection circuit and is suitable for supplying power to two adjacent electrode plates.

Optionally, the power supply circuit includes: an AC power supply, whose output voltage amplitude can be adjusted; a voltage doubling circuit, where a first end of the voltage doubling circuit is connected to the positive pole of the AC power supply, and a second end is connected to the positive pole of the AC power supply. connected with the negative pole of the AC power supply; the second pole plate is connected with the voltage doubling circuit, and the first pole plate is connected with the negative pole of the AC power supply through the first sampling resistor; the fourth pole The plate is connected to the voltage doubling circuit, and the third electrode plate is connected to the negative electrode of the AC power supply through the second sampling resistor.

Optionally, the voltage doubling circuit is an eight-folding voltage circuit, and the second pole plate is connected to a four-folding voltage position of the voltage doubling circuit; the fourth pole plate is connected to an eight-folding voltage of the voltage doubling circuit. pressure position.

Optionally, the AC power supply includes: a switch circuit, the control end of the switch circuit is connected to the controller, the first end is connected to a power supply, and the second end is grounded; a transformer, the primary coil of which is used to connect all The control end of the switch circuit is connected to the controller, one end of the secondary coil is connected to the first end of the voltage doubling circuit, and the other end of the secondary coil is connected to the second end of the voltage doubling circuit.

Optionally, the AC power supply further includes: a first capacitor, one end of which is connected to the power supply and the other end is grounded; an electrolytic capacitor, one end of which is connected to the power supply and the other end is grounded.

Optionally, the AC power supply further includes: a second capacitor, the first end of which is connected to the power supply, and the second end is connected to the first end of the switch circuit through a third diode; The cathode of the pole tube is connected to the second end of the second capacitor, the anode of the third diode is connected to the first end of the switch circuit; the third resistor is connected in parallel with the second capacitor.

Optionally, the AC power supply further includes: a bias resistor, arranged between the controller and the control terminal of the switch circuit; a first diode, connected in parallel with the bias resistor; the first diode The cathode of the diode is connected to the controller, the anode is connected to the control terminal of the switch circuit; the cathode of the second diode is connected to the controller, and the anode is connected to the second terminal of the switch circuit.

Optionally, the AC power supply further includes: a third capacitor, one end of which is connected to the first end of the switch circuit, and the other end is connected to the second end of the switch circuit.

Compared with the prior art, the technical solution of the present invention has the following advantages:

1. An embodiment of the present invention provides a detection circuit, the detection circuit is set in an air purification device, and the detection circuit includes: a sampling circuit, which is connected in series with one of two adjacent electrode plates; a voltage detection circuit, which is connected with the The sampling circuits are connected in parallel; the voltage detection circuit is used to detect the voltage across the sampling circuits.

In this way, during the long-term use of the air purification device, since the dust and impurities on the pole plates will increase, the relative distance between the two adjacent pole plates will be shortened, and the distance between the pole plates will be too close, which will cause The current flowing through the sampling circuit will become larger, so that the voltage collected by the voltage detection circuit will become larger. Thereby, the user can know the actual working condition of the air purification device in time.

2. The present invention also provides an air purification device, the air purification device comprising: any one of the detection circuits; a power supply circuit, connected to the detection circuit, and suitable for supplying power to two adjacent electrode plates .

In this way, when the voltage collected by the voltage detection circuit in the detection circuit exceeds the threshold value, the voltage of the power supply circuit can be manually or automatically controlled to reduce the voltage of the power supply circuit to avoid arcing, discharge, ignition and other phenomena between the plates. play a protective role. The power circuit can also be turned off, and the first and second plates can be cleaned, so as to avoid arcing, discharge, ignition and other phenomena between the plates and prolong the service life of the air purification device.

Description of drawings

In order to illustrate the specific embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present invention. For ordinary workers in the art, other drawings can also be obtained from these drawings without any creative effort.

1 is a schematic diagram of a detection circuit according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of the overall circuit of the air purification device according to the embodiment of the present invention.

Reference number:

The first sampling resistor R5; the second sampling resistor R6;

The first plate B1; the second plate B2; the third plate B3; the fourth plate B4;

The first switch K1; the second switch K2;

Power supply VCC; MOS tube Q1; high frequency transformer T1;

The second resistor R2; the third resistor R3; the fourth resistor R4;

The first capacitor C1; the second capacitor C2; the third capacitor C3; the electrolytic capacitor EC1;

The first diode D1; the second diode D2; the third diode D3; the Zener diode D12.

Detailed ways

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary workers in the art without creative work fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the indicated device or element must have a specific orientation or a specific orientation. construction and operation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection connection, or integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components, which can be a wireless connection or a wired connection connect. For ordinary workers in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

With the improvement of people's living standards, many smart appliances have entered people's lives, and air purifiers are one of the types of people's daily use. In the prior art, air purifiers usually kill germs in the air by means of high-voltage discharge between the plates. However, in the process of long-term use, the dust and impurities in the air will gradually accumulate on the plates, which will shorten the relative distance between the plates. If the relative distance between the plates is shortened, and the high voltage between the plates of the air purifier is not changed, once the distance between the plates is too close, the electric field strength between the plates will increase, and the electric field will flow through the plates where the plates are located. The current of the circuit becomes larger, so that there will be arcing, discharge, ignition and other phenomena between the plates, which will seriously affect the service life of the product. If the user does not know at this time, there will be a certain dangerous situation. The technical problem to be solved by the present invention is that the dust and impurities in the air existing in the prior art will gradually accumulate on the pole plates, so that the electric field strength between the pole plates becomes larger, and the current flowing through the circuit where the pole plates is located becomes larger, Thereby seriously affecting the service life of the product. Thus, a detection circuit and an air purification device are provided.

Example 1

As shown in FIG. 1 , an embodiment of the present invention provides a detection circuit. The detection circuit is provided in an air purification device. The detection circuit specifically includes a sampling circuit and a voltage detection circuit.

The sampling circuit is connected in series between the pole plate and the power supply, and is connected in series with one of the two adjacent pole plates, and the two adjacent pole plates cooperate with each other in the air purification device. One of the two adjacent plates is a discharge electrode and the other is a dust-collecting electrode. The discharge electrode is used for discharge, and the dust-collecting electrode is used for dust-collecting, and impurities such as dust are adsorbed on the dust-collecting electrode. The voltage detection circuit is connected in parallel with the sampling circuit, and the voltage detection circuit is used for detecting the voltage at both ends of the sampling circuit.

During the long-term use of the air purification device, it is easy to cause excessive dust and impurities on the dust collecting electrode, and too much dust and impurities will shorten the relative distance between the discharge electrode and the dust collecting electrode. If the distance between the plates is too short, the electric field strength between the discharge electrode and the dust collecting electrode will increase, so that the current between the electrodes will increase. When the distance between the plates is reduced to a certain extent, flashover, spark discharge or arc discharge will occur between the discharge electrode and the dust collecting electrode, which will cause the current flowing between the plates to increase suddenly, and it will be higher than the normal dust removal state. The current is much larger. Then, the voltage collected by the voltage detection circuit will be higher than the voltage during normal operation.

Therefore, the user can know the actual working condition of the air purification device in time through the voltage fed back by the voltage detection circuit.

In addition, a rectifier and transformer circuit is usually provided in the air purification device, which is used to rectify and transform the alternating current to form a high-voltage direct current. When a flashover occurs between the discharge electrode and the dust collector, a power surge occurs in the rectifier and transformer circuit. The flashover is like an instantaneous short-circuit switch, which induces high-frequency voltage, and may produce an oscillating high voltage. frequency voltage. At this time, the components in the circuit are impacted by the high-frequency voltage, which induces a high voltage drop and forms a high voltage difference. Since the working power of each element will increase, the working power of the entire air purification device will also increase suddenly, so that the air purification device is easily burned out.

Therefore, when the voltage collected by the voltage detection circuit exceeds the threshold value, the voltage of the power supply circuit can be manually or automatically controlled to reduce the voltage of the power supply circuit to avoid arcing, discharge, ignition and other phenomena between the plates, and to protect the air purification device. The power circuit can also be turned off to clean the first plate B1 and the second plate B2, so as to avoid arcing, discharge, ignition and other phenomena between the plates, prolong the service life of the air purification device, and avoid burning the air. Purification device to ensure the safe use of users.

In this embodiment, the electrode plate includes a first electrode plate B1 and a second electrode plate B2, the sampling circuit includes a first sampling resistor R5, and the first sampling resistor R5 is connected in series with the first electrode plate B1, or with the second electrode plate B2 concatenate. As shown in FIG. 1 , the first sampling resistor R5 is connected in series with the second electrode plate B2.

The detection circuit is further provided with a first switch K1, which is connected in series with the first pole plate B1 or in series with the second pole plate B2. As shown in FIG. 2 , the first switch K1 and the second pole plate B2 are connected in series.

During the normal operation of the air purification device, the first switch K1 is in a closed state. When there is too much dust and impurities on the pole plate, and the phenomenon of arcing, discharge, and ignition between pole plates cannot be eliminated by reducing the voltage of the power supply circuit, the first switch K1 can be turned off, and the first pole plate B1 can be disconnected. and the second plate B2 for cleaning, so as to ensure the safe use of the user.

Of course, the air purifying device is also provided with adjacent third plate B3 and fourth plate B4, the third plate B3 is connected to the positive pole of the power supply circuit, and the fourth pole plate B4 is connected to the negative pole of the power supply circuit. In the detection circuit, the sampling circuit further includes a second sampling resistor R6, the second sampling resistor R6 is connected in series with the third electrode plate B3, or is connected in series with the fourth electrode plate B4. As shown in FIG. 1 , the second sampling resistor R6 is connected in series with the fourth polar plate B4.

The detection circuit further includes a second switch K2, the second switch K2 is connected in series with the third pole plate B3, or is connected in series with the fourth pole plate B4. As shown in FIG. 2 , the second switch K2 is connected in series with the fourth pole plate B4.

Those skilled in the art can adjust the number of sampling resistors and the number of switches according to the number of pole plates of the air purification device, so as to ensure the safe operation of the air purification device. The first switch K1 and the second switch K2 may be relays, or may be other switching devices with the same function. Those skilled in the art can replace it according to the actual situation.

When the user is using, if there is a lot of dust and impurities between the first plate B1 and the second plate B2, the normal use of the air purification device has been affected, and the dust and impurities between the third plate B3 and the fourth plate B4 have been affected. With less dust and impurities, it can operate normally. At this time, the user can turn off the first switch K1 and keep the second switch K2 closed, so as to ensure the normal operation of the air purification device and prevent the entire air purification device from working when one group of the pole plates fails to work. disadvantages.

Example 2

Embodiments of the present invention also provide an air purification device, which includes several electrode plate groups, a power supply circuit, and the detection circuit described in the above embodiments. The power supply circuit is connected with the detection circuit and is suitable for supplying power to two adjacent electrode plates. The two adjacent electrode plates are the discharge electrode and the dust collecting electrode respectively. Several pole plate groups are connected in parallel with the power supply circuit, and the pole plate groups include two adjacent pole plates.

Optionally, in some embodiments of the present invention, the power supply circuit includes: an AC power supply and a voltage multiplier circuit. The output voltage amplitude of the AC power supply can be adjusted. The first end of the voltage doubling circuit is connected to the positive pole of the AC power supply, and the second end is connected to the negative pole of the AC power supply. The first pole plate B1 is connected to the voltage doubling circuit, and the second pole plate B2 is connected to the negative pole of the AC power supply through the first sampling resistor R5. The third pole plate B3 is connected to the voltage doubling circuit, and the fourth pole plate B4 is connected to the negative pole of the AC power supply through the second sampling resistor R6. As shown in FIG. 2 , an eight-fold voltage circuit is used in this embodiment. Of course, those skilled in the art can change the specific structure and quantity of the voltage doubling circuit according to the actual situation, as long as the effect of voltage boosting can be achieved.

When the voltage collected by the voltage detection circuit exceeds the threshold, the voltage of the power supply circuit can be manually or automatically controlled to reduce the voltage of the power supply circuit to avoid arcing, discharge, ignition and other phenomena between the plates, and to protect the air purification device. The power circuit can also be turned off, and the first plate B1 and the second plate B2 can be cleaned, so as to avoid arcing, discharge, ignition and other phenomena between the plates, prolong the service life of the air purification device, and ensure the user's safety. Safe to use.

The initial voltage of the voltage doubler circuit can be 1.5KV or higher, depending on the withstand voltage of the voltage doubler capacitor in the voltage doubler circuit. The voltage doubling circuit itself does not contain chips, which makes the voltage doubling circuit highly versatile. The voltage multiplier circuit itself has its own sampling resistor, which can monitor the working condition of the plate itself in real time. At the same time, the magnitude of the working current in the voltage multiplier circuit can be calculated according to the voltage of the sampling resistor.

The AC power supply includes a switching circuit and a high-frequency transformer T1. The control end of the switch circuit is connected with the controller, the first end is connected with the power supply VCC, and the second end is grounded. The primary coil of the high frequency transformer T1 is used to connect the control end of the switching circuit and the controller, one end of the secondary coil is connected to the first end of the voltage multiplier circuit, and the other end of the secondary coil is connected to the second end of the voltage multiplier circuit. The switch circuit can be a triode, a MOS transistor Q1 and other types of switch transistors, which can realize the opening and closing effect.

For example, when the switch circuit is the MOS transistor Q1, the controller generates a pwm wave. When the pwm wave is at a high level, the MOS transistor Q1 is turned on, and the power supply VCC supplies power to the high-frequency transformer T1. The high-frequency transformer T1 passes through the secondary coil to become The voltage multiplier circuit supplies power; when the pwm wave is at a low level, the MOS transistor Q1 is turned off, and the power supply VCC cannot supply power to the high-frequency transformer T1. In this way, the controller can provide pulse voltage for the high-frequency transformer T1 by generating pwm waves. After the high-frequency transformer T1 is stepped down or boosted, the high-frequency transformer T1 can output AC voltage, thereby inputting the AC voltage into the voltage multiplier circuit.

When the sampling circuit detects that the voltage between the first plate B1 and the second plate B2 is too high, the controller can control the pwm wave to reduce the duty cycle, thereby reducing the AC voltage generated by the high-frequency transformer T1, thereby reducing the times The voltage of the voltage circuit, thereby reducing the voltage between the first plate B1 and the second plate B2 and the voltage between the third plate B3 and the fourth plate B4, to avoid arcing, discharge, and ignition between the plates. and other phenomena, play a protective role in the air purification device. The sampling circuit and the controller can be electrically connected, or when the user sees that the voltage of the sampling circuit is too high, the controller can be manually controlled to protect the air purification device.

Moreover, the pwm wave can also not be generated by the controller, so that there is no voltage between the first pole plate B1 and the second pole plate B2, between the third pole plate B3 and the fourth pole plate B4, and the first pole plate B1 and the The second pole plate B2, the third pole plate B3 and the fourth pole plate B4 do not work at this time. The user can then remove the first electrode plate B1 and the second electrode plate B2, the third electrode plate B3 and the fourth electrode plate B4 from the detection circuit or from the air purification device for cleaning to ensure the normal operation of the air purification device. In this way, the phenomenon of arcing, discharge, and ignition between the plates is avoided, and the service life of the air purification device is prolonged, thereby ensuring the safe use of the user.

The voltage detection circuit is more direct and accurate because it directly detects the current on the secondary side of the high-frequency transformer T1. In addition, the voltage detection circuit does not need to undergo oscillation, the interference is small, and the detection is simpler.

Optionally, the detection circuit further includes a first capacitor C1 and an electrolytic capacitor EC1. One end of the first capacitor C1 is connected to the power supply VCC, and the other end is grounded. One end of the electrolytic capacitor EC1 is connected to the power supply VCC, and the other end is grounded. The first capacitor C1 can filter out high frequency signals, and the electrolytic capacitor EC1 is used to filter out low frequency signals.

The detection circuit further includes a second capacitor C2, a third diode D3 and a third resistor R3. The first end of the second capacitor C2 is connected to the power supply VCC, and the second end of the second capacitor C2 is connected to the first end of the switch circuit through the third diode D3. The cathode of the third diode D3 is connected to the second end of the second capacitor C2, and the anode of the third diode D3 is connected to the first end of the switch circuit. The third resistor R3 is connected in parallel with the second capacitor C2. The second capacitor C2, the third resistor R3 and the third diode D3 form an RCD absorption circuit, which is used to absorb the oscillation generated by the high-frequency transformer T1 at the moment when the switching circuit is turned on.

The detection circuit further includes a second resistor R2, a first diode D1 and a second diode D2. The second resistor R2 is arranged between the controller and the control terminal of the switch circuit, the first diode D1 is connected in parallel with the second resistor R2, the cathode of the first diode D1 is connected to the controller, and the anode is connected to the control terminal of the switch circuit connect. The cathode of the second diode D2 is connected to the controller, and the anode is connected to the second end of the switch circuit. The first diode D1 is used for discharging the junction capacitance of the MOS transistor Q1, which can optimize the switching of the MOS transistor Q1. The second diode D2 can protect the IO port of the controller.

Optionally, in some embodiments of the present invention, a third capacitor C3 is further included. One end of the third capacitor C3 is connected to the first end of the switch circuit, and the other end is connected to the second end of the switch circuit. The third capacitor C3 can be used to absorb electronic noise generated when the switching circuit is switched.

The detection circuit is also provided with a Zener diode D12, the positive pole of the Zener diode D12 is grounded, and the negative pole is connected to the control terminal of the switch circuit. The detection circuit is also provided with a fourth resistor R4, one end of which is connected to the control end of the switch circuit, and the other end is grounded.

Obviously, the above-mentioned embodiments are only examples for clear description, and are not intended to limit the implementation manner. For ordinary workers in the field, changes or changes in other different forms can also be made on the basis of the above description. There is no need and cannot be exhaustive of all implementations here. And the obvious changes or changes derived from this are still within the protection scope of the present invention.

Claims (13)

1. A detection circuit, comprising:

the sampling circuit is connected between a power supply and the polar plate in series and is connected with one of the two adjacent polar plates in series;

the voltage detection circuit is connected with the sampling circuit in parallel; the voltage detection circuit is used for detecting the voltage at two ends of the sampling circuit.

2. The detection circuit of claim 1,

the polar plates comprise a first polar plate (B1) and a second polar plate (B2) which are adjacently arranged;

the sampling circuit comprises a first sampling resistor (R5), the first sampling resistor (R5) being in series with the first plate (B1) or in series with the second plate (B2).

3. The detection circuit of claim 2, further comprising: a first switch (K1), the first switch (K1) being in series with the first plate (B1) or in series with the second plate (B2).

4. The detection circuit of claim 3,

the polar plates also comprise a third polar plate (B3) and a fourth polar plate (B4) which are adjacently arranged;

the sampling circuit further comprises a second sampling resistor (R6), the second sampling resistor (R6) being in series with the third plate (B3) or in series with the fourth plate (B4).

5. The detection circuit of claim 4, further comprising:

a second switch (K2), the second switch (K2) being in series with the third plate (B3) or in series with the fourth plate (B4).

6. An air purification apparatus, comprising:

the detection circuit of claim 5;

the power supply circuit is connected with the detection circuit;

a plurality of plate groups connected in parallel with the power circuit; the polar plate group comprises two adjacent polar plates.

7. The detection circuit of claim 6,

the power supply circuit includes: the output voltage of the alternating current power supply can be adjusted; the voltage doubling circuit is connected with the positive pole of the alternating current power supply at a first end and connected with the negative pole of the alternating current power supply at a second end;

the first polar plate (B1) is connected with the voltage doubling circuit, and the second polar plate (B2) is connected with the negative pole of the alternating current power supply through the first sampling resistor (R5);

the third polar plate (B3) is connected with the voltage doubling circuit, and the fourth polar plate (B4) is connected with the negative pole of the alternating current power supply through the second sampling resistor (R6).

8. The detection circuit of claim 7, wherein the voltage doubling circuit is an eight voltage doubling circuit, the first plate (B1) is connected to a quadruple voltage position of the voltage doubling circuit, and the third plate (B3) is connected to the eight voltage doubling position of the voltage doubling circuit.

9. The detection circuit of claim 8, wherein the ac power source comprises:

the control end of the switch circuit is connected with the controller, the first end of the switch circuit is connected with a power supply (VCC), and the second end of the switch circuit is grounded;

a high frequency transformer (T1), a primary coil of the high frequency transformer (T1) is used for connecting the control end of the switch circuit and the controller, one end of a secondary coil is connected with the first end of the voltage doubling circuit, and the other end of the secondary coil is connected with the second end of the voltage doubling circuit.

10. The detection circuit of claim 9, further comprising:

a first capacitor (C1) having one end connected to the power supply (VCC) and the other end grounded;

and one end of the electrolytic capacitor (EC1) is connected with the power supply (VCC), and the other end of the electrolytic capacitor is grounded.

11. The detection circuit of claim 10, further comprising:

a second capacitor (C2), a first terminal of which is connected to the power supply (VCC), and a second terminal of which is connected to the first terminal of the switch circuit via a third diode (D3); the cathode of the third diode (D3) is connected with the second end of the second capacitor (C2), and the anode of the third diode (D3) is connected with the first end of the switch circuit;

a third resistor (R3) connected in parallel with the second capacitor (C2).

12. The detection circuit according to any one of claims 9 to 11, further comprising:

a second resistor (R2) disposed between the controller and the control terminal of the switching circuit;

a first diode (D1) connected in parallel with the second resistor (R2); the negative electrode of the first diode (D1) is connected with the controller, and the positive electrode of the first diode is connected with the control end of the switch circuit;

and a second diode (D2) having a cathode connected to the controller and an anode connected to the second terminal of the switching circuit.

13. The detection circuit according to any one of claims 9 to 11, further comprising:

and a third capacitor (C3) having one end connected to the first end of the switch circuit and the other end connected to the second end of the switch circuit.

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