A method and device for detecting whether a filter screen is in good contact

Abstract

The present application relates to the field of purification technology, and in particular to a method and device for detecting whether a filter is in good contact. The method includes obtaining a negative high-voltage DC current on the filter and converting the DC current into a voltage signal; performing reverse operation amplification on the voltage signal to obtain a positive DC voltage and then output it through the output terminal; when the filter is connected, obtaining the output voltage of the output terminal to determine whether there is a DC voltage at the output terminal; when there is a DC voltage at the output terminal, the filter is in good contact. The present application solves the problem that during the actual use of a purifier based on electrostatic dust removal, the user cannot detect whether the filter is in good contact, resulting in a weakened purification effect of the purifier or even no purification effect. The present application has the effect of improving the purification effect of the purifier.

Description

Technical Field

[0001] The present application relates to the field of purification technology, and in particular to a method and device for detecting whether a filter screen is in good contact. Background Art

[0002] Electrostatic dust removal is a method of gas dust removal. Its principle is: dust-containing gas is electrically separated when passing through a high-voltage electrostatic field. After the dust particles combine with negative ions and carry negative charges, they tend to discharge and deposit on the anode surface. That is, in a strong electric field, air molecules are ionized into positive ions and electrons. When the electrons rush to the positive electrode, they encounter dust particles, causing the dust particles to be negatively charged and adsorbed to the positive electrode and collected.

[0003] The purifier based on electrostatic dust removal uses a conductive plastic material filter. By connecting high voltage electricity and ensuring good contact between the filter, the purifier has a good purification effect without the need to replace the filter. Conventional activated carbon adsorption filters cannot remove dust when saturated, so the filter needs to be replaced regularly.

[0004] However, the purifier needs to be connected to the filter through wires to supply power, and during the assembly process, it is impossible to determine whether the wires are in good contact or whether the filter is installed correctly.

[0005] Regarding the above-mentioned related technologies, the inventors believe that there is a defect that in the actual use of the existing electrostatic dust removal-based purifier, the user cannot detect whether the filter is in good contact, resulting in a weakened purification effect of the purifier or even no purification effect. Summary of the invention

[0006] In order to ensure that the purifier has a good purification effect, the present application provides a method and device for detecting whether the filter is in good contact.

[0007] On the first aspect, the present application provides a method for detecting whether the filter is in good contact, which has the characteristic of ensuring a good purification effect of the purifier.

[0008] This application is achieved through the following technical solutions:

[0009] A method for detecting whether a filter screen is in good contact comprises the following steps:

[0010] Obtaining a negative high-voltage direct current on the filter screen, and converting the direct current into a voltage signal;

[0011] Performing reverse operation amplification on the voltage signal to obtain a positive DC voltage which is then outputted through the output terminal;

[0012] When the filter is connected, the output voltage of the output terminal is obtained to determine whether there is a DC voltage at the output terminal; when there is a DC voltage at the output terminal, it is determined that the filter is in good contact.

[0013] By adopting the above technical scheme, the negative high-voltage DC current on the filter is obtained to stabilize the negative high-voltage DC power supply, and the current is converted into a voltage signal for measurement, so as to overcome the problem that the current at the uA (microampere) level is too small to be detected during detection, which is convenient for signal acquisition and detection, and also improves the accuracy of the filter installation detection result; and because the negative voltage power supply cannot be directly collected, the negative high-voltage DC voltage signal is reversely amplified to obtain a positive DC voltage, which further improves the detection accuracy of the filter installation; when the filter is connected, it is determined whether there is a DC voltage at the output end to detect whether the filter is in good contact and whether the installation is accurate; when there is a DC voltage at the output end When there is voltage at the output end, the filter is in good contact and is installed correctly; when there is no DC voltage at the output end, the filter is in poor contact and is installed incorrectly; furthermore, a method for detecting whether the filter is in good contact can be used in the actual use of a purifier based on electrostatic dust removal. By detecting the current value on the filter, it is determined whether the wires of the purifier are in good contact during the assembly process, that is, whether the filter is installed correctly, so that the user can perceive the actual contact of the filter to ensure that the filter is in good contact and installed in place when the purifier is working, thereby ensuring that the purifier has a good purification effect, and improving the situation where the purification effect of the purifier is weakened or even has no purification effect due to the user's inability to perceive whether the filter is in good contact.

[0014] In a preferred example, the present application can be further configured as follows: while the step of obtaining the negative high-voltage direct current on the filter screen, the following steps are also included:

[0015] Get the DC input voltage;

[0016] Modulating the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity;

[0017] Based on a preset frequency, filtering the triangular wave to obtain a periodic pulsating DC triangular wave;

[0018] The periodic DC triangular wave is output after being boosted to obtain a negative high-voltage DC power supply to supply power to the filter.

[0019] By adopting the above technical solution, the acquired DC input voltage is modulated into two pulsating triangular waves of equal magnitude and opposite polarity to pre-process the DC input voltage, so that the signal to be detected subsequently obtained from the filter has good linearity and good volt-frequency characteristics, which is conducive to detecting the installation of the filter; based on the preset frequency, the triangular wave is filtered to select a suitable pulsating triangular wave frequency, attenuate the inappropriate waveform, filter out the interference signal, and output a periodic pulsating DC triangular wave frequency that meets the preset frequency after the circuit is stable, so that the quality of the periodic pulsating DC triangular wave obtained is better, which is more conducive to detecting the installation of the filter; the input After a group of pulsating DC triangular waves are stepped up, a high-voltage periodic AC triangular wave is obtained, and then a negative high-voltage DC power supply is obtained to power the filter, so that the signal to be detected subsequently obtained from the filter is amplified and processed, thereby improving the detection accuracy of the filter contact problem; therefore, since the transformer has two flux changes in one cycle, the present application changes the flux change of the transformer, presets the LC resonant frequency, and outputs a negative high-voltage DC voltage in the self-excitation mode to power the filter, which is beneficial to measure the tiny current generated when the filter is working, and assists in detecting whether the filter is in good contact, thereby improving the detection accuracy and the accuracy of the filter installation detection results.

[0020] In a preferred example, the present application can be further configured to: enable the periodic DC triangular wave voltage boost to include multiple voltage boost.

[0021] By adopting the above technical solution, the periodic DC triangular wave is multiplied to boost the voltage, which meets the requirements of the filter element working voltage during the operation of the purifier.

[0022] In a preferred example, the present application can be further configured as: matching multiple diodes and multiple capacitors to perform multiple voltage boosting on the periodic DC triangular wave.

[0023] By adopting the above technical solution, multiple diodes and multiple capacitors are used for voltage doubling rectification to obtain high voltage, and the high-voltage periodic AC triangular wave is boosted by multiple times to output a negative high-voltage DC voltage to power the filter, which meets the working voltage requirements of the filter element, ensures the purification effect of the filter, and has a simple design.

[0024] In a preferred example, the present application can be further configured as follows: obtaining the negative high-voltage DC current on the filter screen through a sampling resistor, stabilizing the negative high-voltage DC power supply, and converting the current into a voltage signal.

[0025] By adopting the above technical solution, the sampling resistor can stabilize the negative high-voltage DC power supply and convert the current into a voltage signal for measurement. It has the advantages of low impedance, precise tolerance, high temperature resistance, and high current operating environment, which is beneficial to improving the accuracy of the filter installation detection results.

[0026] In a preferred example, the present application may be further configured as follows: using an inverse amplifier to perform inverse operational amplification on the voltage signal.

[0027] By adopting the above technical solution, the reverse amplifier amplifies the input voltage signal and outputs it in reverse, so as to indirectly collect the negative voltage power supply, obtain the positive DC voltage, and further improve the accuracy of the filter installation detection result.

[0028] In a preferred example, the present application can be further configured as follows: the preset frequency is designed by a ZVS circuit.

[0029] By adopting the above technical solution and designing a ZVS circuit, the appropriate pulsating triangular wave frequency is selected with the LC resonant frequency, the frequency value is set, the inappropriate waveform is attenuated, the interference signal is filtered out, and after the circuit is stable, a periodic pulsating DC triangular wave frequency that meets the preset frequency is output, so that the quality of the periodic pulsating DC triangular wave is better, which is conducive to detecting whether the filter contact is good; at the same time, when the switch tube is turned off or turned on, the voltage across its two ends is 0, so that the switching loss of the switch tube is minimized.

[0030] On the second aspect, the present application provides a device for detecting whether the filter is in good contact, which has the characteristic of ensuring a good purification effect of the purifier.

[0031] This application is achieved through the following technical solutions:

[0032] A device for detecting whether a filter screen is in good contact, comprising:

[0033] A current sampling module is used to obtain the negative high-voltage direct current on the filter and convert the direct current into a voltage signal;

[0034] A voltage sampling module is used to perform reverse operation amplification on the voltage signal to obtain a positive DC voltage, and then output it through the output terminal;

[0035] The detection module is used to determine whether there is a DC voltage at the output end when the filter is connected; when there is a DC voltage at the output end, it is determined that the filter is in good contact.

[0036] By adopting the above technical solution, the current sampling module obtains the negative high-voltage DC current on the filter, stabilizes the negative high-voltage DC power supply, and converts the current into a voltage signal for measurement, so as to overcome the problem that the current at the uA level is too small to be detected during detection, facilitate signal acquisition and detection, and also help to improve the accuracy of the filter installation detection result; because the negative voltage power supply cannot be directly collected, the voltage sampling module performs reverse operation amplification on the negative high voltage voltage to obtain a positive DC voltage, which further improves the detection accuracy of the filter installation; when the filter is connected, the detection module detects whether the filter is in good contact by judging whether there is a DC voltage at the output end, and then a device for detecting whether the filter is in good contact can be used in the actual use of the purifier based on electrostatic dust removal. By detecting the current value on the filter, it can be determined whether the wire of the purifier is in good contact during the assembly process, that is, whether the filter is correctly installed, so that the user can perceive the actual contact of the filter, so as to ensure that the filter is in good contact and installed in place when the purifier is working, and ensure that the purifier has a good purification effect, and improve the situation where the purification effect of the purifier is weakened or even has no purification effect due to the user's inability to perceive whether the filter is in good contact.

[0037] In a preferred example, the present application can be further configured as follows:

[0038] A DC voltage module, used to obtain a DC input voltage;

[0039] A half-bridge DC chopper module, used to modulate the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity;

[0040] A filtering module, used for filtering the triangular wave based on a preset frequency to obtain a periodic pulsating DC triangular wave;

[0041] The boost module is used to boost the DC triangular wave to output a negative high-voltage DC power supply to supply power to the filter.

[0042] By adopting the above technical solution, the DC voltage module outputs a DC input voltage; the half-bridge DC chopper module modulates the input DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity to pre-process the DC input voltage, so that the signal to be detected subsequently obtained from the filter has good linearity and good volt-frequency characteristics, which is conducive to detection; the filter module generates a triangular wave based on the resonant frequency to obtain a periodic pulsating DC triangular wave, and obtains a negative high-voltage DC power supply after being boosted by the multi-voltage circuit of the boost module to power the filter, so that the signal to be detected subsequently obtained from the filter is amplified and processed, thereby improving the detection accuracy of the filter contact problem; and then based on the DC voltage module, the half-bridge DC chopper module, the filter module and the boost module, by changing the magnetic flux change of the transformer, the LC resonant frequency is preset, and in the self-excitation mode, a negative high-voltage DC voltage is output to power the filter, which is conducive to measuring the tiny current generated when the filter is working, and assists in detecting whether the filter is in good contact, thereby improving the detection accuracy and the accuracy of the filter installation detection result.

[0043] In a preferred example, the present application can be further configured as follows: the boost module includes a multiple voltage boost unit, and the multiple voltage boost unit is used to perform multiple voltage boost on the periodic DC triangular wave.

[0044] By adopting the above technical solution, the multi-times voltage boosting unit enables the periodic DC triangular wave to be multiplied in voltage boosting, which meets the requirements of the filter element working voltage, ensures the purification effect of the filter, and also protects the filter.

[0045] In summary, the present application includes at least one of the following beneficial technical effects:

[0046] 1. A method for detecting whether a filter is in good contact can determine whether the wires of the purifier are in good contact during the assembly process by detecting the current value on the filter during the actual use of the purifier based on electrostatic dust removal, that is, whether the filter is correctly installed, so that the user can feel the actual contact of the filter to ensure that the filter is in good contact and installed in place when the purifier is working, ensuring that the purifier has a good purification effect, and improving the situation where the purification effect of the purifier is weakened or even has no purification effect due to the user's inability to detect whether the filter is in good contact;

[0047] 2. This application changes the flux change of the transformer, presets the LC resonant frequency, and outputs a negative high-voltage DC voltage in the self-excitation mode to power the filter, which is beneficial to measure the tiny current generated when the filter is working, and assists in detecting whether the filter is in good contact, thereby improving the detection accuracy and the accuracy of the filter installation detection result;

[0048] 3. Matching multiple diodes and multiple capacitors can multiply the voltage of the periodic DC triangle wave to meet the working voltage requirements of the filter element, ensure the purification effect of the filter, and also protect the filter. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 It is a flow chart of a method for detecting whether a filter is in good contact according to one embodiment of the present application.

[0050] Figure 2 It is a structural block diagram of a device for detecting whether a filter is in good contact, in one embodiment of the present application.

[0051] Figure 3 The diagram is a schematic diagram of the main circuit connection relationship of a device for detecting whether the filter is in good contact. DETAILED DESCRIPTION

[0052] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] In addition, the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article, unless otherwise specified, generally means that the associated objects before and after are in an "or" relationship.

[0055] The embodiments of the present application are further described in detail below in conjunction with the drawings in the specification.

[0056] Reference Figure 1 , an embodiment of the present application provides a method for detecting whether the filter is in good contact, and the main steps of the method are described as follows.

[0057] S1: Get DC input voltage;

[0058] S2: modulate the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity;

[0059] S3: Based on the preset frequency, filter the triangular wave to obtain a periodic pulsating DC triangular wave;

[0060] S4: The periodic DC triangular wave is output after being boosted to obtain a negative high-voltage DC power supply to power the filter;

[0061] S5: At the same time, stabilize the negative high voltage DC power supply and convert the current into a voltage signal.

[0062] S6: Perform reverse operation amplification on the voltage signal to obtain a positive DC voltage, which is then output through the output terminal;

[0063] S7: Determine whether there is a DC voltage at the output terminal; when there is a DC voltage at the output terminal, it is determined that the filter is in good contact.

[0064] Further, S3: based on the preset frequency, the preset frequency is designed by a ZVS circuit, wherein the ZVS circuit design refers to a zero voltage switching circuit design.

[0065] Furthermore, a sampling resistor is used to stabilize a negative high voltage DC power supply to obtain a sampling current, which is then converted into a voltage signal for reverse operational amplification.

[0066] Further, boosting the periodic DC triangular wave includes multiple voltage boosting. Further, matching multiple diodes and multiple capacitors enables the periodic DC triangular wave to perform multiple voltage boosting.

[0067] In this embodiment, the periodic DC triangular wave is tripled in voltage. If the voltage is low, the filter performance cannot be brought into play, and if the voltage is high, there is a risk of the filter element being broken down. The triple voltage boost is selected to ensure the purification effect of the filter and also protect the filter.

[0068] Further, S6: when performing reverse operational amplification on the negative high-voltage DC power supply, a reverse amplifier is used to perform reverse operational amplification on the negative high-voltage DC power supply.

[0069] Wherein, S1: obtains the DC input voltage by obtaining the DC voltage output from the inverter power supply to obtain the DC input voltage.

[0070] S2: Modulate the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity to pre-process the DC input voltage so that the signal to be detected subsequently obtained from the filter has good linearity and volt-frequency characteristics, which is conducive to detection.

[0071] S3: Based on the preset frequency, filter the triangular wave to obtain a periodic pulsating DC triangular wave, and through ZVS circuit design, select the appropriate pulsating triangular wave frequency with the LC resonant frequency, design the preset frequency value, attenuate the inappropriate waveform, filter out the interference signal, and output a periodic pulsating DC triangular wave frequency that meets the preset frequency after the circuit is stable, so that the quality of the periodic pulsating DC triangular wave is better; when the switch tube is turned off or turned on, the voltage across it is 0, so that the switching loss of the switch tube is minimized.

[0072] S4: The periodic DC triangular wave is output after being boosted to obtain a negative high-voltage DC power supply to power the filter. Specifically, a group of pulsating DC triangular waves are input, and two pulsating DC triangular waves are boosted to obtain a high-voltage periodic AC triangular wave, and then a negative high-voltage DC power supply is obtained to power the filter. The signal to be detected obtained from the filter subsequently is amplified and processed to improve the detection accuracy.

[0073] S5: At the same time, the negative high voltage DC power supply is stabilized, and the current is converted into a voltage signal for measurement, which is beneficial to improving the accuracy of the detection result. The negative high voltage DC power supply is stabilized by a sampling resistor, and the current is converted into a voltage signal for measurement. The sampling resistor has a small resistance value and has the advantages of low impedance value, precise tolerance, high temperature resistance, and high current use environment.

[0074] Because the negative voltage power supply cannot be directly collected, S6: the negative high voltage DC power supply is reversely amplified, and the input signal is amplified and output inverted with the help of a reverse amplifier to obtain a positive DC voltage to indirectly collect the negative voltage power supply, which also further improves the detection accuracy.

[0075] S7: Determine whether there is a DC voltage at the output terminal, and detect whether the filter is in good contact by determining whether there is a DC voltage at the output terminal; when there is a DC voltage at the output terminal, the filter is in good contact; when there is no DC voltage at the output terminal, the filter is in poor contact.

[0076] Furthermore, the periodic DC triangular wave voltage boost includes multiple voltage boost, and a high-voltage diode is used to perform multiple voltage boost on the periodic DC triangular wave. The design is simple, meets the requirements of the filter element working voltage, ensures the purification effect of the filter, and also protects the filter.

[0077] Furthermore, a method for detecting whether the filter is in good contact can determine whether the wires of the purifier are in good contact during the assembly process, that is, whether the filter is correctly installed, by detecting the current value on the filter during the actual use of the purifier based on electrostatic dust removal, so that the user can feel the actual contact of the filter to ensure that the filter is in good contact and installed in place when the purifier is working, thereby ensuring that the purifier has a good purification effect, and improving the situation where the purification effect of the purifier is weakened or even has no purification effect due to the user's inability to perceive whether the filter is in good contact.

[0078] It should be understood that the size of the serial numbers of the steps in the above embodiments does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0079] Reference Figure 2 The embodiment of the present application also provides a device for detecting whether the filter screen is in good contact, and the device for detecting whether the filter screen is in good contact corresponds to the method for detecting whether the filter screen is in good contact in the above embodiment. The device for detecting whether the filter screen is in good contact includes:

[0080] A DC voltage module, used to obtain a DC input voltage;

[0081] A half-bridge DC chopper module is used to modulate the input DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity;

[0082] A filtering module, used for filtering the triangular wave based on a preset frequency to obtain a periodic pulsating DC triangular wave;

[0083] The boost module is used to output the periodic DC triangular wave after boosting to obtain a negative high-voltage DC power supply to power the filter;

[0084] The current sampling module is used to stabilize the negative high-voltage DC power supply, obtain the sampling current and then convert the current into a voltage signal output;

[0085] The voltage sampling module is used to perform reverse operation amplification on the acquired voltage signal to obtain a positive DC voltage, and then output it through the output terminal;

[0086] The detection module is used to determine whether there is a DC voltage at the output end when the filter is connected; when there is a DC voltage at the output end, it is determined that the filter is in good contact.

[0087] Furthermore, the boost module includes a multiple voltage boost unit, and the multiple voltage boost unit is used to perform multiple voltage boost on the periodic DC triangular wave.

[0088] Reference Figure 3The DC input voltage of the DC voltage input module is input into the input end of the half-bridge DC chopper module via the OUT+ end. The adjustable range of the DC input voltage is 11V to 15.6V, corresponding to the output high voltage of 8KV to 12KV.

[0089] In this embodiment, the direct current input voltage may be a direct current input voltage.

[0090] The half-bridge DC chopper module includes a first MOS (field effect transistor) tube Q1 and a second MOS tube Q2, wherein the first MOS tube Q1 and the second MOS tube Q2 are both N MOS tubes, and the first MOS tube Q1 and the second MOS tube Q2 are arranged in parallel.

[0091] The DC input voltage is connected to the gate of the first MOS tube Q1 via the first diode D1 and the second resistor R2. The first diode D1 and the second resistor R2 are arranged in series. The source of the first MOS tube Q1 is connected to the input end of the boost module, and the drain of the first MOS tube Q1 is grounded.

[0092] The DC input voltage is connected to the gate of the second MOS transistor Q2 via the first diode D1 and the third resistor R3. The first diode D1 and the third resistor R3 are connected in series. The source of the second MOS transistor Q2 is grounded. The drain of the second MOS transistor Q2 is connected to another input end of the boost module.

[0093] A third diode D3 is forwardly connected between the gate of the first MOS transistor Q1 and the source of the second MOS transistor Q2. The third diode D3 is a voltage stabilizing diode.

[0094] A second diode D2 is forwardly connected between the gate of the second MOS transistor Q2 and the source of the first MOS transistor Q1. The second diode D2 is a voltage stabilizing diode.

[0095] The gate of the first MOS transistor Q1 is grounded via a fifth resistor R5, and the fifth resistor R5 is located at an end of the second resistor R2 close to the first MOS transistor Q1.

[0096] The gate of the second MOS transistor Q2 is grounded via a fourth resistor R4 , and the fourth resistor R4 is located at an end of the third resistor R3 close to the second MOS transistor Q2 .

[0097] The input DC input voltage is then modulated into two pulsating triangular waves of equal magnitude and opposite polarity by the first MOS transistor Q1 and the second MOS transistor Q2.

[0098] Furthermore, the filter module can be a ZVS module, which includes a first capacitor C1 and a first inductor L1. The first capacitor C1 is located between the gate of the first MOS tube Q1 and the drain of the second MOS tube Q2, and the first inductor L1 is located between the anode of the first diode D1 and the boost module.

[0099] According to the excitation saturation, the first MOS transistor Q1 and the second MOS transistor Q2 are turned on or off in turn, so that the first capacitor C1 and the first inductor L1 filter the pulsating triangular wave to obtain a periodic pulsating DC triangular wave.

[0100] Further, the boost module includes a first transformer T1, which may be a high-frequency transformer. Port 6 of the first transformer T1 is connected to the source of the first MOS tube Q1, port 1 of the first transformer T1 is connected to the drain of the second MOS tube Q2, port 3 of the first transformer T1 is connected to the first inductor L1, port 11 of the first transformer T1 is grounded via the seventh resistor R7 and the eighth resistor R8, and the seventh resistor R7 and the eighth resistor R8 are connected in series.

[0101] Then, a group of periodic pulsating DC triangular waves are input into the two primary input ends of the first transformer T1 respectively. The two pulsating triangular waves are boosted by the first transformer T1 to output negative high-voltage periodic DC triangular waves. The boost module includes a triple-voltage boost unit. The negative high-voltage periodic DC triangular wave is boosted by the triple-voltage boost unit to output negative high-voltage DC voltage to power the filter.

[0102] Because the transformer has two flux changes in one cycle, the present application is based on a DC voltage input module, a half-bridge DC chopper module, a ZVS module, a high-frequency transformer and a triple voltage boost unit. By changing the flux change of the high-frequency transformer and presetting the LC resonant frequency, the high-frequency transformer works in a self-excited mode instead of an externally excited mode, and outputs a negative high-voltage DC voltage to power the filter, which is beneficial for measuring the tiny current generated when the filter is working, so as to detect whether the filter is in good contact, thereby improving the detection accuracy and the accuracy of the detection results.

[0103] Wherein, the triple voltage boost unit includes a sixth diode D6, a seventh diode D7 and an eighth diode D8, the sixth diode D6, the seventh diode D7 and the eighth diode D8 are high voltage diodes, the sixth diode D6, the seventh diode D7 and the eighth diode D8 are arranged in parallel, the anode of the sixth diode D6 is connected to the 11 port of the first transformer T1 via the fourth capacitor C4, and the cathode of the sixth diode D6 is connected to the 8 port of the first transformer T1; the anode of the seventh diode D7 is connected to the 8 port of the first transformer T1, the cathode of the sixth diode D6 and the anode of the seventh diode D7 are connected to the second capacitor C2, and the cathode of the seventh diode D7 is connected to the anode of the sixth diode D6;

[0104] The anode of the eighth diode D8 is connected to the cathode of the seventh diode D7 via the third capacitor C3, and the cathode of the eighth diode D8 is connected to the 8th port of the first transformer T1; so as to triple the voltage of the high-voltage periodic AC triangular wave and output a negative high-voltage DC voltage to power the filter.

[0105] In this embodiment, a triple voltage boost circuit is used to meet the filter element working voltage requirements. During the operation of the purifier, if the voltage is low, the filter performance is not fully utilized, and if the voltage is high, there is a risk of the filter element being broken down. The triple voltage boost circuit ensures the purification effect of the filter and also protects the filter.

[0106] Further, the current sampling module includes a first resistor R1, the first resistor R1 is connected to the anode of the eighth diode D8 via a sixth resistor R6 and a ninth resistor R9, and the sixth resistor R6 and the ninth resistor R9 are arranged in series.

[0107] Specifically, the first resistor R1 is a sampling resistor, which collects negative voltage DC power through the sampling resistor and converts the current into a voltage signal output to overcome the problem that the current at the uA level is difficult to detect due to being too small.

[0108] Further, the voltage sampling module includes an operational amplifier U1, which is a reverse amplifier. The negative input terminal of the operational amplifier U1 is connected to the output terminal of the first resistor R1 via the tenth resistor R10, and the positive input terminal of the operational amplifier U1 is connected to the output terminal of the first resistor R1 via the seventeenth resistor R17, the fourteenth resistor R14, the fifth capacitor C5 and the transient suppression diode TVS1, the fourteenth resistor R14, the fifth capacitor C5 and the transient suppression diode TVS1 are connected in parallel, the fifth capacitor C5 is a polarity capacitor, the positive pole of the fifth capacitor C5 is grounded, the positive input terminal of the operational amplifier U1 is grounded via the seventeenth resistor R17, and the output terminal of the operational amplifier U1 is grounded via the eighth capacitor C8.

[0109] Then, the operational amplifier U1 performs a reverse operational amplification with a gain of 1 on the collected voltage signal to obtain a positive DC voltage output.

[0110] Furthermore, the detection module includes a third transistor Q3, which is an NPN type. The output end of the operational amplifier U1 is connected to the base of the third transistor Q3 via the sixteenth resistor R16, the collector of the third transistor Q3 is connected to the 5V voltage via the eleventh resistor R11, the collector of the transistor Q3 outputs the positive DC voltage obtained by the operational amplifier U1, an eighteenth resistor R18 is connected between the base of the third transistor Q3 and the emitter of the third transistor Q3, and the emitter of the third transistor Q3 is grounded.

[0111] Furthermore, when the filter is connected, whether the collector of transistor Q3 has a DC voltage output is determined to detect whether the filter has good contact; when there is a DC voltage at the output end, the filter has good contact; when there is no DC voltage at the output end, the filter has poor contact.

[0112] Each module in the above-mentioned device for detecting whether the filter is in good contact can be implemented in whole or in part by software, hardware, or a combination thereof. Each module can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each module.

[0113] A person skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory.

[0114] Those skilled in the art will clearly understand that for the sake of convenience and brevity of description, only the division of the above-mentioned functional units and modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional units and modules as needed, that is, the internal structure of the system can be divided into different functional units or modules to complete all or part of the functions described above.

Claims

1. A method for detecting whether a filter screen is in good contact, characterized in that: The following steps are involved: Obtaining a negative high-voltage direct current on the filter screen, and converting the direct current into a voltage signal; Performing reverse operation amplification on the voltage signal to obtain a positive DC voltage which is then outputted through the output terminal; When the filter is connected, the output voltage of the output terminal is obtained to determine whether there is a DC voltage at the output terminal; when there is a DC voltage at the output terminal, it is determined that the filter is in good contact; The step of obtaining the negative high-voltage direct current on the filter screen also includes the following steps: Get the DC input voltage; Modulating the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity; Based on a preset frequency, filtering the triangular wave to obtain a periodic pulsating DC triangular wave; The periodic DC triangular wave is output after being boosted to obtain a negative high-voltage DC power supply to supply power to the filter.

2. The method for detecting whether the filter screen is in good contact according to claim 1, characterized in that: Boosting the periodic DC triangular wave includes multiple voltage boosting.

3. The method for detecting whether the filter screen is in good contact according to claim 2, characterized in that: A plurality of diodes and a plurality of capacitors are matched to perform multiple voltage boosting on the periodic DC triangular wave.

4. The method for detecting whether the filter screen is in good contact according to any one of claims 1 to 3, characterized in that: The negative high-voltage DC current on the filter is obtained through the sampling resistor, the negative high-voltage DC power supply is stabilized, and the current is converted into a voltage signal.

5. The method for detecting whether the filter screen is in good contact according to any one of claims 1 to 3, characterized in that: An inverse amplifier is used to perform inverse operational amplification on the voltage signal.

6. The method for detecting whether the filter screen is in good contact according to any one of claims 1 to 3, characterized in that: The preset frequency is designed by a ZVS circuit.

7. A device for detecting whether a filter screen is in good contact, characterized in that: include: A current sampling module is used to obtain the negative high-voltage direct current on the filter and convert the direct current into a voltage signal; A voltage sampling module is used to perform reverse operation amplification on the voltage signal to obtain a positive DC voltage, and then output it through the output terminal; A detection module, used to determine whether there is a DC voltage at the output end when the filter is connected; When there is a DC voltage at the output end, it is judged that the filter is in good contact; Also includes: A DC voltage module, used to obtain a DC input voltage; A half-bridge DC chopper module, used to modulate the DC input voltage into two pulsating triangular waves of equal magnitude and opposite polarity; A filtering module, used for filtering the triangular wave based on a preset frequency to obtain a periodic pulsating DC triangular wave; The boost module is used to boost the DC triangular wave to output a negative high-voltage DC power supply to supply power to the filter.

8. The device for detecting whether the filter screen is in good contact according to claim 7, characterized in that: The boost module includes a multiple voltage boost unit, and the multiple voltage boost unit is used to perform multiple voltage boost on the periodic DC triangular wave.

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