Voltage doubling rectification type negative high voltage output circuit

Abstract

The utility model relates to the technical field of negative-ion generators, and discloses a voltage-multiplying rectification type negative high voltage output circuit, which comprises a frequency voltage regulating circuit, a transformer circuit and a multi-stage voltage-multiplying rectification circuit, and is characterized in that a first end of the frequency voltage regulating circuit is connected with a first input end of the transformer circuit and inputs positive direct current voltage, and a second end of the frequency voltage regulating circuit is connected with a second input end of the transformer circuit; the second end of the frequency voltage regulating circuit is connected with the first end of the transformer circuit and the first end of the multi-stage voltage doubling rectifying circuit and inputs negative direct-current voltage; the third end and the fourth end of the frequency voltage regulating circuit are correspondingly connected with the second input end and the third input end of the transformer circuit respectively; the first output end and the second output end of the transformer circuit are correspondingly connected with the first end and the second end of the multi-stage voltage doubling rectifying circuit respectively. According to the utility model, the problems of output voltage drop and easy arc discharge damage after glue filling packaging are solved, and the circuit integration level and the safety are improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to negative ion generator technical field, concretely relates to a kind of double voltage rectifier type negative high voltage output circuit. BACKGROUND

[0002] The performance core of negative ion generator is the performance of its high-voltage generating circuit. Currently, the industry is generally faced with a technical dilemma: to achieve high-voltage output, the circuit is often designed to be complex and large in size, making it difficult to integrate; while simple circuit design often results in unstable output voltage, susceptibility to environmental interference, and even significant performance degradation after key production process steps due to insufficient electrical isolation or poor load adaptability.

[0003] The existing technology mainly has the following problems:

[0004] (1) Conflict between integration and performance: traditional high-voltage circuits require extremely large core voltage elements or complex circuit topologies to achieve high-voltage output, which not only limits product miniaturization but also increases manufacturing costs, making it difficult to meet the needs of modern electronic devices for compact modules.

[0005] (2) Lack of stability and reliability: especially after applying encapsulation processes such as glue filling, the distribution parameters in the circuit will change significantly, causing the original operating point to shift and resulting in a significant drop in output voltage, which severely affects the final performance and yield of the product. At the same time, the circuit is prone to arcing, breakdown, and other phenomena under transient changes or harsh environments, with insufficient safety margin.

[0006] (3) Output quality needs to be improved: the high-voltage DC output of some existing technologies has a large ripple and low purity, which directly affects the efficiency and stability of corona discharge, thereby restricting the further improvement of negative ion generation concentration and quality. INVENTION CONTENTS

[0007] The utility model provides a kind of double voltage rectifier type negative high voltage output circuit to solve the problem of low safety degree of negative high voltage output circuit in prior art.

[0008] The utility model provides a kind of negative high voltage output circuit of voltage doubler rectifier, comprising: frequency voltage regulating circuit, transformer circuit and multistage voltage doubler rectifier circuit, wherein, the first end of frequency voltage regulating circuit is connected with the first input end of transformer circuit and inputs positive direct current voltage, the second end of frequency voltage regulating circuit is connected with the first end of transformer circuit and the first end of multistage voltage doubler rectifier circuit and inputs negative direct current voltage, the third end and the fourth end of frequency voltage regulating circuit are respectively connected with the second input end and the third input end of transformer circuit correspondingly, and frequency voltage regulating circuit is used to output alternating voltage after direct current voltage oscillation;The second end and the third end of multistage voltage doubler rectifier circuit are respectively connected with the second output end and the third output end of transformer circuit correspondingly, and transformer circuit is used to step up and isolate alternating voltage;Multistage voltage doubler rectifier circuit is used to output negative high voltage after multistage voltage doubler rectifier circuit is used to step up and rectify alternating voltage.

[0009] The voltage doubler rectifier type negative high voltage output circuit provided by the utility model utilizes multistage voltage doubler rectifier circuit to step up alternating voltage in stages, so that transformer circuit, which is most sensitive to distributed capacitance, does not need to work in extreme high voltage state, reduces the risk of internal arc caused by insufficient insulation of transformer circuit itself, and thereby improves voltage stability and reliability of the circuit after integrated packaging from the root, improves circuit safety degree. In addition, the embodiment adopts the architecture combining transformer circuit step-up and secondary step-up of multistage voltage doubler rectifier circuit, so that transformer circuit does not need to output target high voltage at one time by setting extremely high number of turns ratio, but only needs to step up to intermediate voltage by lower number of turns ratio, and then step up intermediate voltage to target voltage by multistage voltage doubler rectifier circuit, which simplifies manufacturing process and volume of transformer circuit and improves circuit integration.

[0010] In an alternative embodiment, the frequency voltage regulating circuit comprises: a buffer circuit and an oscillation circuit, wherein the first end of the buffer circuit is connected with the first input end of the transformer circuit and inputs positive direct current voltage, the second end of the buffer circuit is connected with the first end of the oscillation circuit, the first end of the transformer circuit and the first end of the multistage voltage doubler rectifier circuit, and inputs negative direct current voltage, and the buffer circuit is used to stabilize direct current voltage;The second end and the third end of the oscillation circuit are respectively connected with the second input end and the third input end of the transformer circuit correspondingly, and the oscillation circuit is used to switch on-off state of internal switch based on internal time parameter, so that direct current voltage is converted into alternating voltage of target frequency.

[0011] In an alternative embodiment, the buffer circuit comprises: a first capacitor, wherein the two ends of the first capacitor respectively input positive direct current voltage and negative direct current voltage.

[0012] In an alternative embodiment, the oscillation circuit comprises a second capacitor, a third capacitor, a first resistor, a second resistor and a controllable switch, wherein the first end of the second capacitor connected in parallel with the first resistor is connected to the second input end of the transformer circuit, the second end of the second capacitor connected in parallel with the first resistor is connected to the first end of the second resistor, the second end of the second resistor is connected to the control end of the controllable switch and the first end of the third capacitor, the second end of the third capacitor is connected to the first end of the controllable switch and the second end of the buffer circuit, and the second end of the controllable switch is connected to the third input end of the transformer circuit.

[0013] In an alternative embodiment, the transformer circuit comprises a third resistor and a transformer, wherein the first end of the primary winding of the transformer is connected to the second end of the oscillation circuit, the second end of the primary winding of the transformer is connected to the third end of the oscillation circuit and the first end of the third resistor, the middle tap of the primary winding of the transformer is connected to the first end of the buffer circuit, the first end and the second end of the secondary winding of the transformer are respectively connected to the second end and the third end of the multi-stage voltage doubling rectification circuit, the second end of the third resistor is connected to the second end of the buffer circuit, and the ground end of the transformer is grounded.

[0014] The negative high voltage output circuit provided by the embodiment has the transformer grounded, which reduces the distributed capacitance between the primary winding and the secondary winding of the transformer, thereby avoiding the arc phenomenon caused by the transient breakdown of the insulation between the primary winding and the secondary winding, and significantly reducing the common mode interference.

[0015] In an alternative embodiment, the multi-stage voltage doubling rectification circuit comprises a first-stage voltage doubling rectification unit, a second-stage voltage doubling rectification unit and a third-stage voltage doubling rectification unit, wherein the first end of the first-stage voltage doubling rectification unit is connected to the first output end of the transformer circuit and the first end of the third-stage voltage doubling rectification unit, the second end and the third end of the first-stage voltage doubling rectification unit are respectively connected to the second output end and the first end of the transformer circuit, the third end of the first-stage voltage doubling rectification unit is connected to the first end of the second-stage voltage doubling rectification unit, the second end and the third end of the second-stage voltage doubling rectification unit are respectively connected to the second end and the third end of the third-stage voltage doubling rectification unit and output negative high voltage, and the first-stage voltage doubling rectification unit, the second-stage voltage doubling rectification unit and the third-stage voltage doubling rectification unit are used to sequentially step up and rectify the alternating voltage.

[0016] In an alternative embodiment, the first-stage voltage doubling rectification unit comprises a first diode and a fourth capacitor, wherein the cathode of the first diode is connected to the first end of the third-stage voltage doubling rectification unit, the anode of the first diode is connected to the first end of the fourth capacitor and the first end of the second-stage voltage doubling rectification unit, and the second end of the fourth capacitor is connected to the second output end of the transformer circuit.

[0017] In an alternative embodiment, the second-stage voltage doubling rectifier unit comprises a second diode and a fifth capacitor, wherein the cathode of the second diode is connected to the first end of the fifth capacitor and the third end of the first-stage voltage doubling rectifier unit, and the anode of the second diode is connected to the second end of the third-stage voltage doubling rectifier unit; the second end of the fifth capacitor is connected to the third end of the third-stage voltage doubling rectifier unit.

[0018] In an alternative embodiment, the third-stage voltage doubling rectifier unit comprises a third diode and a sixth capacitor, wherein the cathode of the third diode is connected to the first end of the sixth capacitor and the second end of the second-stage voltage doubling rectifier unit, and the anode of the third diode is connected to the third end of the second-stage voltage doubling rectifier unit; the second end of the sixth capacitor is connected to the first end of the first-stage voltage doubling rectifier unit.

[0019] In an alternative embodiment, the multi-stage voltage doubling rectifier circuit further comprises a first output protection circuit and a second output protection circuit, wherein the first end of the first output protection circuit is connected to the third end of the first-stage voltage doubling rectifier unit, and the second end of the first output protection circuit is connected to the first end of the transformer circuit; the first end of the second output protection circuit is connected to the third end of the third-stage voltage doubling rectifier unit, and the second end of the second output protection circuit outputs negative high voltage; the first output protection circuit and the second output protection circuit are both used for current limiting; the first output protection circuit and the second output protection circuit both comprise a glass enamel resistor.

[0020] The first output protection circuit and the second output protection circuit can limit the current flowing therethrough, thereby avoiding arc phenomenon, and the glass enamel resistor is stable in performance under high voltage and is not easy to be broken down, so that the reliability of current limiting protection is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the following will briefly introduce the drawings needed to be used in the specific embodiments or the prior art description. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can also obtain other drawings according to these drawings without creative labor.

[0022] Figure 1 is the first constituent diagram of the voltage doubling rectifier type negative high voltage output circuit according to the embodiment of the present application;

[0023] Figure 2 is the second constituent diagram of the voltage doubling rectifier type negative high voltage output circuit according to the embodiment of the present application;

[0024] Figure 3 is the specific circuit diagram of the voltage doubling rectifier type negative high voltage output circuit according to the embodiment of the present application;

[0025] Figure 4 is a first constituent diagram of a multi-stage voltage doubling rectifier circuit according to an embodiment of the present application;

[0026] Figure 5 is a second constituent diagram of a multi-stage voltage doubling rectifier circuit according to an embodiment of the present application. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0028] It can be understood that, before using the technical scheme disclosed in each embodiment of the present application, the user should be informed of the type, use range, use scenario and the like of the personal information involved in the present application and obtain the authorization of the user in a proper manner according to relevant laws and regulations.

[0029] The terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more than two, unless otherwise explicitly and specifically limited.

[0030] In order to realize good insulation, heat conduction and mechanical protection, high-voltage circuits often use glue filling packaging. However, the glue filling material will introduce a large parasitic distributed capacitance. The voltage gain of the traditional negative high-voltage output circuit depends on the transformer, and the number of turns of the secondary side is large, and the distributed capacitance is already large. After glue filling, this distributed capacitance and the inter-turn capacitance and ground capacitance of the transformer form a stronger capacitive load, which seriously shunts the voltage boosting efficiency of the transformer, resulting in a large and non-negligible drop in output voltage after glue filling, which seriously affects the final performance of the negative ion generator.

[0031] The embodiment provides a voltage doubling rectifier type negative high-voltage output circuit for providing negative high-voltage excitation for a negative ion generator, as shown in Figure 1 The voltage doubling rectifier type negative high-voltage output circuit includes a frequency voltage regulation circuit 1, a transformer circuit 2 and a multi-stage voltage doubling rectifier circuit 3.

[0032] Figure 1In the embodiment, the first end of the frequency-voltage regulating circuit 1 is connected with the first input end of the transformer circuit 2 and inputs a positive direct current voltage DC+, the second end of the frequency-voltage regulating circuit 1 is connected with the first end of the transformer circuit 2 and the first end of the multi-stage voltage-boosting rectifier circuit 3 and inputs a negative direct current voltage DC-, the third end and the fourth end of the frequency-voltage regulating circuit 1 are respectively connected with the second input end and the third input end of the transformer circuit 2, and the frequency-voltage regulating circuit 1 is used to output an alternating current voltage after oscillation of the direct current voltage.

[0033] Specifically, Figure 1 In the embodiment, the direct current voltage is input from the first end of the frequency-voltage regulating circuit 1, and after flowing through the transformer circuit 2, the frequency-voltage regulating circuit 1 provides an energy basis for oscillation, and then changes the internal switch on-off frequency through oscillation to provide an alternating magnetic field for the transformer circuit 2.

[0034] Optionally, Figure 1 In the embodiment, the frequency-voltage regulating circuit 1 includes an RC network and a switch device for determining the oscillation frequency of the circuit, and a high-frequency switch square wave signal with a controllable frequency is generated by the RC network timing and the positive feedback of the transformer circuit 2, and is applied to the switch device in the frequency-voltage regulating circuit 1, so that the switch device outputs a square wave current with a high frequency and an amplitude equal to the input direct current voltage, and is applied to the input end of the transformer circuit 2.

[0035] Figure 1 In the embodiment, the first output end and the second output end of the transformer circuit 2 are respectively connected with the second end and the third end of the multi-stage voltage-boosting rectifier circuit 3, and the transformer circuit 2 is used to boost and isolate the alternating current voltage.

[0036] Specifically, Figure 1 In the embodiment, the transformer circuit 2 outputs a primary alternating current voltage after voltage transformation and electrical isolation through electromagnetic induction of the alternating current voltage output by the frequency-voltage regulating circuit 1.

[0037] Optionally, the ground end of the transformer circuit is grounded, which can improve the electrical isolation between the low-voltage side and the high-voltage side of the transformer circuit, reduce the distributed capacitance between the low-voltage side and the high-voltage side of the transformer circuit, suppress high-frequency noise and energy coupling, and avoid the arc phenomenon caused by instantaneous breakdown of insulation between the primary and secondary.

[0038] Figure 1 In the embodiment, the multi-stage voltage-boosting rectifier circuit 3 is used to output a negative high voltage after multi-stage voltage boosting and rectification of the alternating current voltage.

[0039] Specifically, Figure 1In this circuit, the multi-stage voltage multiplier rectifier circuit 3 sequentially boosts and rectifies the AC voltage output from the transformer circuit 2 through a multi-stage voltage multiplier network, then superimposes it to output a DC negative high voltage. Finally, it converts the primary AC voltage on the secondary side of the transformer into a stable DC high voltage with a target amplitude much higher than the original voltage, which is then applied to the negative ion generator. Due to the multi-stage voltage multiplier rectifier circuit 3, the transformer circuit 2 can output a lower primary AC voltage; that is, the transformer circuit 2 does not need to output the target high voltage all at once by setting an extremely high turns ratio, thus reducing the circuit size.

[0040] Optionally, the voltage level of the negative high voltage in this embodiment can be from -2kV to -7.5kV, used to provide high-voltage corona discharge for the negative ion generator to ionize the air.

[0041] The voltage multiplier rectifier negative high-voltage output circuit provided in this embodiment utilizes a multi-stage voltage multiplier rectifier circuit to progressively boost the AC voltage. This eliminates the need for the transformer circuit, which is most sensitive to distributed capacitance, to operate at its extreme high voltage. This reduces the risk of internal arcing due to insufficient insulation in the transformer circuit, thereby fundamentally improving the voltage stability and reliability of the integrated package and enhancing circuit safety. Furthermore, this embodiment employs an architecture combining transformer circuit boosting and multi-stage voltage multiplier rectifier circuit secondary boosting. The transformer circuit does not need to output the target high voltage all at once with an extremely high turns ratio. Instead, it only needs to boost the voltage to an intermediate voltage using a lower turns ratio, and then use the multi-stage voltage multiplier rectifier circuit to boost the intermediate voltage to the target voltage a second time. This simplifies the manufacturing process and reduces the size of the transformer circuit, improving circuit integration.

[0042] In some alternative implementations, such as Figure 2 As shown, the frequency voltage regulation circuit 1 includes a buffer circuit 11 and an oscillation circuit 12. The first terminal of the buffer circuit 11 is connected to the first input terminal of the transformer circuit 2 and receives a positive DC voltage DC+. The second terminal of the buffer circuit 11 is connected to the first terminal of the oscillation circuit 12, the first terminal of the transformer circuit 2, and the first terminal of the multi-stage voltage multiplier rectifier circuit 3, and receives a negative DC voltage DC-. The buffer circuit 11 is used to stabilize the DC voltage. The second and third terminals of the oscillation circuit 12 are respectively connected to the second and third input terminals of the transformer circuit 2. The oscillation circuit 12 is used to switch the on / off state of the internal switch based on the internal time parameter, so that the DC voltage is converted into an AC voltage of the target frequency.

[0043] Specifically, Figure 3 In the buffer circuit 11, a first capacitor C1 is included, wherein the two ends of the first capacitor C1 (i.e., the A1 input terminal and the A2 input terminal) are respectively input with a positive DC voltage and a negative DC voltage.

[0044] Specifically, Figure 3In the embodiment, the first capacitor C1 filters the ripple and transient interference in the input DC voltage by using the direct-current blocking characteristic of the capacitor, so that the voltage input to the oscillation circuit 12 is more stable, and a reliable DC bias is provided for subsequent frequency modulation.

[0045] Specifically, Figure 3 In the embodiment, the oscillation circuit 12 comprises a second capacitor C2, a third capacitor C3, a first resistor R1, a second resistor R2, and a controllable switch Q1. The first end of the second capacitor C2 connected in parallel with the first resistor R1 is connected to the second input end of the transformer circuit 2, and the second end of the second capacitor C2 connected in parallel with the first resistor R1 is connected to the first end of the second resistor R2. The second end of the second resistor R2 is connected to the control end of the controllable switch Q1 and the first end of the third capacitor C3. The second end of the third capacitor C3 is connected to the first end of the controllable switch Q1 and the second end of the buffer circuit 11. The second end of the controllable switch Q1 is connected to the third input end of the transformer circuit 2.

[0046] Specifically, Figure 3 In the embodiment, the second capacitor C2 and the first resistor R1 form a first RC network as a charge-discharge circuit, and the time constant τ1=R1×C2 thereof determines the basic charge-discharge frequency. The second resistor R2 and the third capacitor C3 form a second RC network, and the time constant τ2=R2×C3 thereof is used to modify τ1, so that the voltage variation frequency of the control end of the controllable switch Q1 is controlled, and the on and off periods of the controllable switch Q1 are accurately controlled. When the base voltage of the controllable switch Q1 reaches the on threshold, the controllable switch Q1 is saturated and on, and the primary winding of the transformer circuit 2 is powered on. When the base voltage of the controllable switch Q1 is lower than the on threshold, the controllable switch Q1 is off, and the primary winding of the transformer circuit 2 is powered off. Based on the above high-frequency on-off, the primary winding of the transformer circuit 2 generates an alternating magnetic field, which provides conditions for the voltage step-up of the secondary winding of the transformer circuit 2.

[0047] Optionally, by adjusting the element parameters in the first RC network and the second RC network, the switching frequency of the controllable switch Q1 can be changed.

[0048] In some optional embodiments, as shown in Figure 3 The transformer circuit 2 comprises a third resistor R3 and a transformer T1. The first end of the primary winding of the transformer T1 is connected to the second end of the oscillation circuit 12. The second end of the primary winding of the transformer T1 is connected to the third end of the oscillation circuit 12 and the first end of the third resistor R3. The middle tap of the primary winding of the transformer T1 is connected to the first end of the buffer circuit 11. The first end and the second end of the secondary winding of the transformer T1 are respectively connected to the second end and the third end of the multi-stage voltage doubler rectifier circuit 3. The second end of the third resistor R3 is connected to the second end of the buffer circuit 11. The ground end of the transformer T1 is grounded.

[0049] Specifically,Figure 3 In the high-frequency square wave current of the controllable switch Q1, a high-frequency alternating voltage is induced on the secondary coil of the transformer T1, and the voltage increasing ratio is determined by the turns ratio of the transformer. Therefore, in order to reduce the volume of the transformer T1, the turns ratio of the transformer can be reduced, thereby improving the integration of the circuit.

[0050] It should be noted that, Figure 3 The transformer T1 in the high-voltage output circuit is grounded, which can physically separate the low-voltage control circuit (i.e., the primary side) from the high-voltage output circuit (i.e., the secondary side) to improve user safety, and can prevent noise and transient interference on the high-voltage side from being coupled into the sensitive primary control circuit through the ground line, thereby improving the stability of the overall circuit. Good isolation design can also reduce the distributed capacitance between the primary and the secondary, thereby reducing the arc phenomenon caused by the sudden change of the potential difference.

[0051] In some optional embodiments, as shown in Figure 4 For example, as shown in FIG. 3, the multi-stage voltage doubling rectifier circuit 3 includes a first-stage voltage doubling rectifier unit 31, a second-stage voltage doubling rectifier unit 32, and a third-stage voltage doubling rectifier unit 33. The first end of the first-stage voltage doubling rectifier unit 31 is connected to the first output end of the transformer circuit 2 and the first end of the third-stage voltage doubling rectifier unit 33. The second end and the third end of the first-stage voltage doubling rectifier unit 31 are respectively connected to the second output end and the first end of the transformer circuit 2. The fourth end of the first-stage voltage doubling rectifier unit 31 is connected to the first end of the second-stage voltage doubling rectifier unit 32. The second end and the third end of the second-stage voltage doubling rectifier unit 32 are respectively connected to the second end and the third end of the third-stage voltage doubling rectifier unit 33 and output a negative high voltage. The first-stage voltage doubling rectifier unit 31, the second-stage voltage doubling rectifier unit 32, and the third-stage voltage doubling rectifier unit 33 are used to sequentially step up and rectify the alternating voltage.

[0052] Optionally, as shown in Figure 5 The multi-stage voltage doubling rectifier circuit 3 further includes a first output protection circuit 34 and a second output protection circuit 35. The first end of the first output protection circuit 34 is connected to the third end of the first-stage voltage doubling rectifier unit 31. The second end of the first output protection circuit 34 is connected to the first end of the transformer circuit 2. The first end of the second output protection circuit 35 is connected to the third end of the third-stage voltage doubling rectifier unit 33. The second end of the second output protection circuit 35 outputs a negative high voltage. The first output protection circuit 34 and the second output protection circuit 35 are both used for current limiting. The first output protection circuit 34 and the second output protection circuit 35 both include a high-resistance glass enamel resistor.

[0053] Specifically, Figure 3In the embodiment, the first output protection circuit 34 comprises a fourth resistor R4, and the second output protection circuit 35 comprises a fifth resistor R5. The fourth resistor R4 and the fifth resistor R5 are both glass enamel resistors, and have the characteristics of high voltage resistance, high stability and low temperature coefficient. The fourth resistor R4 limits the current of the output end, so as to prevent the output circuit from being damaged by excessive current when the negative ion generator is short-circuited or abnormally discharged; and the fifth resistor R5 can shunt when transient high voltage or surge occurs in the circuit, so as to avoid the capacitor and the diode from being broken down, and at the same time, suppress the arc phenomenon in the bare machine state, and protect the entire high-voltage output circuit.

[0054] Specifically, Figure 3 In the embodiment, the first-stage voltage doubling rectification unit 31 comprises a first diode D1 and a fourth capacitor C4, wherein the cathode of the first diode D1 is connected with the first end of the third-stage voltage doubling rectification unit 33, the anode of the first diode D1 is connected with the first end of the fourth capacitor C4 and the first end of the second-stage voltage doubling rectification unit 32, and the second end of the fourth capacitor C4 is connected with the second output end of the transformer circuit 2 through the fourth resistor R4.

[0055] Specifically, Figure 3 In the embodiment, the second-stage voltage doubling rectification unit 32 comprises a second diode D2 and a fifth capacitor C5, wherein the cathode of the second diode D2 is connected with the first end of the fifth capacitor C5 and the third end of the first-stage voltage doubling rectification unit 31, the anode of the second diode D2 is connected with the second end of the third-stage voltage doubling rectification unit 33, and the second end of the fifth capacitor C5 is connected with the third end of the third-stage voltage doubling rectification unit 33.

[0056] Specifically, Figure 3 In the embodiment, the third-stage voltage doubling rectification unit 33 comprises a third diode D3 and a sixth capacitor C6, wherein the cathode of the third diode D3 is connected with the first end of the sixth capacitor C6 and the second end of the second-stage voltage doubling rectification unit 32, the anode of the third diode D3 is connected with the third end of the second-stage voltage doubling rectification unit 32, and the second end of the sixth capacitor C6 is connected with the first end of the first-stage voltage doubling rectification unit 31.

[0057] Exemplarily, Figure 3 In the embodiment, the secondary side of the transformer T1 outputs a sine wave alternating voltage, and the working process of the multi-stage voltage doubling rectification circuit 3 is as follows:

[0058] (1) In the first positive half cycle of the sine wave, that is, when the voltage on the secondary side of the transformer T1 is positive on the upper end and negative on the lower end, D1 is forward conducting, current flows through D1 to charge C4, and finally the voltage across C4 is charged to Vp, and the polarity is negative on the upper end and positive on the lower end. At this time, D2 and D3 are reverse cut-off, and C5 and C6 have no charging action.

[0059] (2) In the first negative half cycle of the sine wave, that is, when the secondary voltage of transformer T1 is negative on the top and positive on the bottom, D1 is reverse cut-off, and the voltage of C4 is kept at Vp. At this time, the total voltage is 2Vp, which is the sum of the voltage of the secondary of transformer T1 and the voltage of C4, D2 is forward conducting, and the current charges C5, and the voltage across C5 is charged to 2Vp with the polarity of left negative and right positive. At this time, D3 is reverse cut-off, and C6 has no charging action.

[0060] (3) In the second positive half cycle of the sine wave, that is, when the secondary voltage of transformer T1 is positive on the top and negative on the bottom, D1 is forward conducting again, and the voltage of C4 is kept at Vp. At this time, the total voltage is 3Vp, which is the sum of the voltage of the secondary of transformer T1 and the voltage of C5, D3 is forward conducting, and the current charges C6, and the voltage across C6 is charged to 3Vp with the polarity of left negative and right positive.

[0061] (4) After several cycles of charging according to the above on-off rule, C4 is stabilized at Vp, C5 is stabilized at 2Vp, and C6 is stabilized at 3Vp. Finally, the negative high voltage of 3 times the peak value of the secondary of transformer T1 is obtained from the output end of the circuit (i.e. the output terminal of A3).

[0062] Although the embodiments of the utility model are described in combination with the drawings, various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the utility model, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A voltage multiplier rectifier negative high voltage output circuit, characterized in that, include: Frequency regulation circuit, transformer circuit, and multi-stage voltage multiplier rectifier circuit, among which, The first terminal of the frequency voltage regulation circuit is connected to the first input terminal of the transformer circuit and inputs a positive DC voltage. The second terminal of the frequency voltage regulation circuit is connected to the first terminal of the transformer circuit and the first terminal of the multi-stage voltage multiplier rectifier circuit and inputs a negative DC voltage. The third and fourth terminals of the frequency voltage regulation circuit are respectively connected to the second and third input terminals of the transformer circuit. The frequency voltage regulation circuit is used to oscillate the DC voltage and output an AC voltage. The first and second output terminals of the transformer circuit are respectively connected to the second and third terminals of the multi-stage voltage multiplier rectifier circuit. The transformer circuit is used to boost and isolate the AC voltage. The multi-stage voltage multiplier rectifier circuit is used to boost and rectify the AC voltage in multiple stages to output a negative high voltage.

2. The voltage doubler rectifier negative high voltage output circuit according to claim 1, characterized in that, The frequency regulation circuit includes: a buffer circuit and an oscillation circuit, wherein... The first terminal of the buffer circuit is connected to the first input terminal of the transformer circuit and receives a positive DC voltage. The second terminal of the buffer circuit is connected to the first terminal of the oscillation circuit, the first terminal of the transformer circuit, and the first terminal of the multi-stage voltage multiplier rectifier circuit and receives a negative DC voltage. The buffer circuit is used to stabilize the DC voltage. The second and third terminals of the oscillation circuit are respectively connected to the second and third input terminals of the transformer circuit. The oscillation circuit is used to switch the on / off state of the internal switch based on the internal time parameter, so that the DC voltage is converted into the AC voltage of the target frequency.

3. The voltage doubler rectifier negative high voltage output circuit according to claim 2, characterized in that, The buffer circuit includes: a first capacitor, wherein, The first capacitor is connected to a positive DC voltage and a negative DC voltage, respectively.

4. The voltage doubler rectifier negative high voltage output circuit according to claim 2, characterized in that, The oscillation circuit includes: a second capacitor, a third capacitor, a first resistor, a second resistor, and a controllable switch, wherein... The first end of the second capacitor connected in parallel with the first resistor is connected to the second input terminal of the transformer circuit, and the second end of the second capacitor connected in parallel with the first resistor is connected to the first end of the second resistor. The second end of the second resistor is connected to the control terminal of the controllable switch and the first end of the third capacitor; The second terminal of the third capacitor is connected to the first terminal of the controllable switch and the second terminal of the buffer circuit. The second terminal of the controllable switch is connected to the third input terminal of the transformer circuit.

5. The voltage doubler rectifier negative high voltage output circuit according to claim 2, characterized in that, The transformer circuit includes: a third resistor and a transformer, wherein... The first end of the primary winding of the transformer is connected to the second end of the oscillation circuit, the second end of the primary winding of the transformer is connected to the third end of the oscillation circuit and the first end of the third resistor, the middle tap of the primary winding of the transformer is connected to the first end of the buffer circuit, the first and second ends of the secondary winding of the transformer are respectively connected to the second and third ends of the multi-stage voltage multiplier rectifier circuit, and the grounding terminal of the transformer is grounded. The second end of the third resistor is connected to the second end of the buffer circuit.

6. The voltage doubler rectifier negative high voltage output circuit according to claim 1, characterized in that, The multi-stage voltage multiplier rectifier circuit includes: a first-stage voltage multiplier rectifier unit, a second-stage voltage multiplier rectifier unit, and a third-stage voltage multiplier rectifier unit, wherein... The first end of the first-stage voltage multiplier rectifier unit is connected to the first output end of the transformer circuit and the first end of the third-stage voltage multiplier rectifier unit. The second and third ends of the first-stage voltage multiplier rectifier unit are respectively connected to the second output end and the first end of the transformer circuit. The fourth end of the first-stage voltage multiplier rectifier unit is connected to the first end of the second-stage voltage multiplier rectifier unit. The second and third terminals of the second-stage voltage multiplier rectifier unit are respectively connected to the second and third terminals of the third-stage voltage multiplier rectifier unit and output negative high voltage; The first-stage voltage multiplier rectifier unit, the second-stage voltage multiplier rectifier unit, and the third-stage voltage multiplier rectifier unit are used to sequentially boost and rectify the AC voltage.

7. The voltage doubler rectifier negative high-voltage output circuit according to claim 6, characterized in that, The first-stage voltage multiplier rectifier unit includes: a first diode and a fourth capacitor, wherein, The cathode of the first diode is connected to the first terminal of the third-stage voltage doubler rectifier unit, and the anode of the first diode is connected to the first terminal of the fourth capacitor and the first terminal of the second-stage voltage doubler rectifier unit. The second terminal of the fourth capacitor is connected to the second output terminal of the transformer circuit.

8. The voltage doubler rectifier negative high voltage output circuit according to claim 6, characterized in that, The second-stage voltage multiplier rectifier unit includes: a second diode and a fifth capacitor, wherein, The cathode of the second diode is connected to the first terminal of the fifth capacitor and the third terminal of the first-stage voltage doubler rectifier unit, and the anode of the second diode is connected to the second terminal of the third-stage voltage doubler rectifier unit. The second terminal of the fifth capacitor is connected to the third terminal of the third-stage voltage multiplier rectifier unit.

9. The voltage doubler rectifier negative high voltage output circuit according to claim 6, characterized in that, The third-stage voltage multiplier rectifier unit includes: a third diode and a sixth capacitor, wherein... The cathode of the third diode is connected to the first terminal of the sixth capacitor and the second terminal of the second-stage voltage doubler rectifier unit, and the anode of the third diode is connected to the third terminal of the second-stage voltage doubler rectifier unit. The second terminal of the sixth capacitor is connected to the first terminal of the first-stage voltage multiplier rectifier unit.

10. The voltage doubler rectifier negative high voltage output circuit according to claim 6, characterized in that, The multi-stage voltage multiplier rectifier circuit further includes: a first output protection circuit and a second output protection circuit, wherein... The first terminal of the first output protection circuit is connected to the third terminal of the first stage voltage multiplier rectifier unit, and the second terminal of the first output protection circuit is connected to the first terminal of the transformer circuit. The first terminal of the second output protection circuit is connected to the third terminal of the third-stage voltage multiplier rectifier unit, and the second terminal of the second output protection circuit outputs a negative high voltage. Both the first output protection circuit and the second output protection circuit are used for current limiting; Both the first output protection circuit and the second output protection circuit include glass glaze resistors.

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