High voltage generating circuit

Abstract

The utility model provides a high-voltage generating circuit, which comprises a singlechip circuit, a battery, a quartz crystal oscillating circuit, a transformer oscillating circuit, a voltage-multiplying output circuit, a current sampling circuit and a voltage sampling circuit. In the scheme, the single-chip microcomputer is used for replacing a traditional PWM control chip, and the quartz crystal is used for replacing a traditional resistance-capacitance oscillation network. The PWM signal of the transformer oscillation circuit is generated by the single-chip microcomputer, and the work of the single-chip microcomputer is controlled by a software program written into the single-chip microcomputer, so that the purpose of reducing the starting current can be achieved by limiting the value of the duty ratio of the PWM signal output by the single-chip microcomputer when the circuit starts to work.

Description

Technical Field

[0001] The utility model relates to the technical field of well logging, in particular to a high voltage generating circuit. Background Art

[0002] In oilfield production, in addition to producing oil wells, water injection wells are also used to inject water into the formation to maintain reservoir pressure. To understand the water injection status of each stratum, measurements of the injection wells are necessary. This is known as water absorption profile measurement within the production well series. During injection, the isotope Ba131 is typically injected into the well as a tracer carrier. The tracer accumulates in the injection layer, and natural gamma ray measurements can be used to determine the water absorption of each layer. Water absorption profile logging typically uses a three-parameter logging instrument, which primarily measures well temperature, magnetic positioning, and natural gamma ray. For wells with low injection pressures, direct-reading three-parameter logging instruments are typically used, using cable measurement and surface power supply. However, for wells with high injection pressures, lowering the instrument into the well with cable is difficult. Generally, when surface pressures exceed 30 MPa, storage-type three-parameter logging instruments are used, using slickline measurement and battery-powered downhole instruments. After the measurement is completed, the data is read out from the surface.

[0003] In stored-type three-parameter instruments, the primary source of power consumption comes from the gamma measurement unit, which uses a photomultiplier tube (PMT) as its sensor. The PMT requires a 1000-2000V DC high-voltage power supply to generate the required gamma counts. This DC high voltage is generated by a battery-powered high-voltage generator circuit. To conserve battery power, the high-voltage generator circuit typically only powers the gamma measurement unit when the instrument reaches the target depth and begins measurement.

[0004] When the existing high-voltage generating circuit starts working, the starting current is too large, causing the battery voltage to drop too much, resulting in the logging instrument circuit not being able to work normally due to insufficient power. Utility Model Content

[0005] In view of this, an embodiment of the present invention provides a high voltage generating circuit to achieve the purpose of reducing the starting current.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] The embodiment of the utility model discloses a high voltage generating circuit, which includes: a single chip microcomputer circuit, a battery, a quartz crystal oscillator circuit, a transformer oscillator circuit, a voltage doubling output circuit, a current sampling circuit and a voltage sampling circuit;

[0008] The battery is connected to the single chip microcomputer circuit and the transformer oscillation circuit;

[0009] The clock output terminal of the quartz crystal oscillator circuit is connected to the clock input terminal of the single-chip microcomputer circuit, and the feedback input terminal of the quartz crystal oscillator circuit is connected to the feedback terminal of the single-chip microcomputer circuit;

[0010] The signal output end of the single chip microcomputer circuit is connected to the signal input end of the transformer oscillation circuit for inputting a PWM signal to the transformer oscillation circuit;

[0011] The output end of the transformer oscillation circuit is connected to the input end of the voltage doubler output circuit;

[0012] The sampling end of the current sampling circuit is connected to the transformer oscillation circuit, and the output end of the current sampling circuit is connected to the sampling current input end of the single chip microcomputer circuit;

[0013] The sampling end of the voltage sampling circuit is connected to the output end of the voltage doubling output circuit, and the output end of the voltage sampling circuit is connected to the sampling voltage input end of the single chip microcomputer circuit.

[0014] Preferably, the quartz crystal oscillator circuit comprises: a quartz crystal oscillator, a first capacitor, a second capacitor and a first resistor;

[0015] The clock output end of the quartz crystal oscillator is respectively connected to the clock input end of the single-chip microcomputer circuit, one end of the first capacitor and one end of the first resistor;

[0016] The feedback input end of the quartz crystal oscillator is respectively connected to the feedback end of the single chip microcomputer circuit, one end of the second capacitor and the other end of the first resistor;

[0017] The other end of the first capacitor and the other end of the second capacitor are grounded.

[0018] Preferably, the single chip microcomputer circuit includes: a single chip microcomputer and a single chip microcomputer power supply circuit;

[0019] The single chip computer power supply circuit includes: a high temperature power supply chip, a high temperature chip tantalum capacitor and a second resistor;

[0020] The positive electrode of the battery is connected to the power input pin of the high-temperature power chip and one end of the second resistor, and the other end of the second resistor is connected to the enable pin of the high-temperature power chip;

[0021] The 5V voltage output pin of the high-temperature power supply chip is connected to the positive electrode of the high-temperature tantalum chip capacitor and the VCC pin of the single-chip microcomputer respectively;

[0022] The PWM signal output pin of the single chip microcomputer is connected to the signal input end of the transformer oscillation circuit;

[0023] The sampling current input pin of the single chip microcomputer is connected to the output end of the current sampling circuit;

[0024] The sampling voltage input pin of the single chip microcomputer is connected to the output end of the voltage sampling circuit.

[0025] Preferably, the single chip microcomputer includes: a PIC12F1822 single chip microcomputer.

[0026] Preferably, the high-temperature power supply chip includes: a TLE4476D chip.

[0027] Preferably, the second resistor comprises: a high-temperature chip resistor with a resistance of 10 kΩ and a 0805 package.

[0028] Preferably, the transformer oscillation circuit comprises: a transformer, a MOS tube, a third resistor and a fourth resistor;

[0029] One end of the primary side of the transformer is connected to the positive electrode of the battery, and the other end of the primary side of the transformer is connected to the drain of the MOS tube;

[0030] One end of the secondary side of the transformer is connected to the input end of the voltage doubler output circuit, and the other end of the secondary side of the transformer is grounded;

[0031] The gate of the MOS transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the signal output end of the single chip circuit;

[0032] The source of the MOS transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is grounded.

[0033] Preferably, the current sampling circuit includes: a third capacitor and a fifth resistor;

[0034] One end of the fifth resistor is connected to the source of the MOS transistor, and the other end of the fifth resistor is connected to one end of the third capacitor and the sampling current input end of the single chip microcomputer circuit respectively;

[0035] The other end of the third capacitor is grounded.

[0036] Preferably, the voltage doubler output circuit includes: a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a sixth diode, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor and a ninth capacitor;

[0037] The anode of the first diode is connected to one end of the fifth capacitor, the intersection between the anode of the first diode and one end of the fifth capacitor is connected to the output end of the transformer oscillation circuit as an input end, the cathode of the first diode is connected to one end of the fourth capacitor and the anode of the second diode, and the other end of the fourth capacitor is grounded;

[0038] An anode of the second diode is connected to one end of the sixth capacitor, and a cathode of the second diode is connected to the other end of the fifth capacitor and the anode of the third diode;

[0039] The anode of the third diode is connected to one end of the seventh capacitor, and the cathode of the third diode is connected to the other end of the sixth capacitor and the anode of the fourth diode;

[0040] The anode of the fourth diode is connected to one end of the eighth capacitor, and the cathode of the fourth diode is connected to the other end of the seventh capacitor and the anode of the fifth diode;

[0041] The anode of the fifth diode is connected to one end of the ninth capacitor, and the cathode of the fifth diode is connected to the other end of the eighth capacitor and the anode of the sixth diode;

[0042] The cathode of the sixth diode is connected to the other end of the ninth capacitor, and the intersection point between the cathode of the sixth diode and the ninth capacitor is connected to the sampling end of the voltage sampling circuit as an output end.

[0043] Preferably, the voltage sampling circuit comprises: a potentiometer, a sixth resistor and a tenth capacitor;

[0044] One end of the sixth resistor is connected to the output end of the voltage doubler output circuit and one end of the tenth capacitor;

[0045] The other end of the sixth resistor is connected to one end of the potentiometer, and the other end of the potentiometer is connected to the other end of the tenth capacitor and is grounded;

[0046] The adjustable end of the potentiometer is connected to the sampling voltage input end of the single chip microcomputer circuit.

[0047] Based on the above embodiment of the present invention, a high-voltage generating circuit is provided, comprising: a single-chip microcomputer circuit, a battery, a quartz crystal oscillator circuit, a transformer oscillator circuit, a voltage doubling output circuit, a current sampling circuit, and a voltage sampling circuit; the battery is connected to the single-chip microcomputer circuit and the transformer oscillator circuit; the clock output of the quartz crystal oscillator circuit is connected to the clock input of the single-chip microcomputer circuit, and the feedback input of the quartz crystal oscillator circuit is connected to the feedback of the single-chip microcomputer circuit; the signal output of the single-chip microcomputer circuit is connected to the signal input of the transformer oscillator circuit, for inputting a PWM signal to the transformer oscillator circuit; the output of the transformer oscillator circuit is connected to the input of the voltage doubling output circuit; the sampling terminal of the current sampling circuit is connected to the transformer oscillator circuit, and the output of the current sampling circuit is connected to the sampling current input of the single-chip microcomputer circuit; the sampling terminal of the voltage sampling circuit is connected to the output of the voltage doubling output circuit, and the output of the voltage sampling circuit is connected to the sampling voltage input of the single-chip microcomputer circuit. In this solution, a single-chip microcomputer replaces the traditional PWM control chip, and a quartz crystal replaces the traditional resistor-capacitor oscillator network. The PWM signal of the transformer oscillation circuit is generated by the microcontroller. Since the operation of the microcontroller is controlled by the software program written into the microcontroller, the starting current can be reduced by limiting the duty cycle of the PWM signal output by the microcontroller when the circuit starts working. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0049] Figure 1 A circuit diagram of a high voltage generating circuit disclosed in an embodiment of the present utility model;

[0050] Figure 2 A circuit diagram of another high voltage generating circuit disclosed in an embodiment of the present utility model;

[0051] Figure 3 This is a workflow diagram of a single chip microcomputer U1 disclosed in an embodiment of the present utility model. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0053] In this application, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0054] First, the technical terms appearing in this application are explained as follows:

[0055] Direct-reading three-parameter logging tool: During the logging process, the logging instrument can be powered by the logging cable for real-time monitoring, measuring three parameters: gamma, well temperature, and magnetic positioning.

[0056] A three-parameter logging tool with storage: This battery-powered tool measures gamma ray well temperature and magnetic positioning during the logging process. The measurement data is stored in the tool's memory unit. After the logging is complete, the tool is removed from the wellbore and the stored downhole measurement data is retrieved on the surface.

[0057] Plateau: The output count of the photomultiplier tube is relatively stable within a certain high voltage range. This high voltage range is called the plateau of the photomultiplier tube.

[0058] PWM: Pulse Width Modulation, pulse width modulation.

[0059] As can be seen from the background technology, when the existing high-voltage generating circuit starts working, the starting current is too large, causing the battery voltage to drop too much, resulting in the logging instrument circuit not being able to work properly due to insufficient power. The following is a detailed analysis of the causes of the shortcomings of the existing technology:

[0060] The operating current of a high-voltage generating circuit is generally affected by two factors: the oscillation frequency and the duty cycle. The oscillation signal of the transformer oscillator circuit in existing high-voltage generating circuits is generated by a dedicated PWM control chip. The oscillation frequency is determined by a network of resistors and capacitors, and the duty cycle is determined by the input voltage of the voltage sampling circuit, ranging from zero to nearly 100%. The main disadvantage of this method is that it results in high startup current. Since the duty cycle is determined by the input voltage of the voltage sampling circuit, the lower the input voltage, the greater the duty cycle and the operating current. Therefore, at startup, since the initial input voltage is zero, the duty cycle is maximum, approaching 100%, and the operating current is maximum. This can cause the battery voltage to drop too low during startup for battery-powered storage-type three-parameter logging tools, especially for batteries that have been used for a period of time, causing the entire storage-type three-parameter logging tool circuit to malfunction.

[0061] In addition, the oscillation frequency is determined by the network composed of resistors and capacitors. Since storage-type three-parameter logging instruments are generally used in high-temperature and high-pressure wells, the instruments need to be resistant to high temperatures. Resistors and capacitors are generally greatly affected by temperature, which can easily cause oscillation frequency drift.

[0062] Therefore, the present invention discloses a high-voltage generating circuit. In this solution, a single-chip microcomputer replaces the traditional PWM control chip, and a quartz crystal replaces the traditional resistor-capacitor oscillation network. The PWM signal for the transformer oscillation circuit is generated by the single-chip microcomputer. Because the operation of the single-chip microcomputer is controlled by a software program written into the microcontroller, the starting current can be reduced by limiting the duty cycle of the PWM signal output by the microcontroller at the circuit's initial operation.

[0063] like Figure 1 As shown, it is a circuit diagram of a high-voltage generating circuit disclosed in an embodiment of the present utility model, including: a single-chip computer circuit 1, a battery 2, a quartz crystal oscillator circuit 3, a transformer oscillator circuit 4, a voltage doubling output circuit 5, a current sampling circuit 6 and a voltage sampling circuit 7.

[0064] Specifically, the battery 2 is connected to the single-chip microcomputer circuit 1 and the transformer oscillator circuit 4; the clock output end of the quartz crystal oscillator circuit is connected to the clock input end of the single-chip microcomputer circuit, and the feedback input end of the quartz crystal oscillator circuit is connected to the feedback end of the single-chip microcomputer circuit; the signal output end of the single-chip microcomputer circuit 1 is connected to the signal input end of the transformer oscillator circuit 4, for inputting a PWM signal to the transformer oscillator circuit 4; the output end of the transformer oscillator circuit 4 is connected to the input end of the voltage doubler output circuit 5; the sampling end of the current sampling circuit 6 is connected to the transformer oscillator circuit 4, and the output end of the current sampling circuit 6 is connected to the sampling current input end of the single-chip microcomputer circuit 1; the sampling end of the voltage sampling circuit 7 is connected to the output end of the voltage doubler output circuit 5, and the output end of the voltage sampling circuit 7 is connected to the sampling voltage input end of the single-chip microcomputer circuit 1.

[0065] Among them, the quartz crystal oscillator circuit 3 generates a clock signal and inputs it into the single-chip microcomputer circuit 1. The single-chip microcomputer circuit 1 generates a PWM signal based on the clock signal and inputs it into the transformer oscillator circuit 4 to drive the transformer oscillator circuit 4 to convert the DC power supply of the battery 2 into AC, and provide AC power supply to the voltage doubler output circuit 5. The voltage doubler output circuit 5 doubles the voltage of the AC power supply to obtain a high-voltage output.

[0066] The voltage sampling circuit 7 samples the high voltage output, obtains a voltage sampling signal and inputs it into the single-chip microcomputer circuit 1 to control the duty cycle output of the PWM signal. The voltage sampling circuit 7 samples the current of the transformer oscillation circuit 4, obtains a current sampling signal and inputs it into the single-chip microcomputer circuit 1, so that the single-chip microcomputer circuit 1 can determine whether a fault has occurred.

[0067] Based on the high voltage generating circuit disclosed in the above utility model embodiment, Figure 2 , which is a circuit diagram of another high voltage generating circuit disclosed in an embodiment of the present utility model.

[0068] The quartz crystal oscillator circuit 3 includes: a quartz crystal oscillator Y1, a first capacitor C1, a second capacitor C2 and a first resistor R1.

[0069] The clock output end of the quartz crystal oscillator Y1 is respectively connected to the clock input end of the single-chip microcomputer circuit 1, one end of the first capacitor C1 and one end of the first resistor R1; the feedback input end of the quartz crystal oscillator Y1 is respectively connected to the feedback end of the single-chip microcomputer circuit 1, one end of the second capacitor C2 and the other end of the first resistor R1; the other end of the first capacitor C1 and the other end of the second capacitor C2 are grounded.

[0070] Specifically, the quartz crystal oscillator Y1 uses a high-temperature crystal oscillator in an 8M XTAL package to generate a highly stable oscillation clock signal to provide to the single-chip microcomputer circuit 1. The clock signal is the basis for the operation of the single-chip microcomputer in the single-chip microcomputer circuit 1.

[0071] The first resistor R1 is a 1MΩ high-temperature chip resistor with a 0805 package, and the first capacitor C1 and the second capacitor C2 are 20pF high-temperature chip capacitors with a 0805 package to reduce the impact of high temperature on well logging.

[0072] It should be noted that the oscillation frequency of the traditional PWM control chip is calculated by the charging and discharging of resistors and capacitors, and is affected by the high temperature of well logging, causing drift and resulting in drift of the output oscillation frequency. The output oscillation frequency of the single-chip microcomputer in the embodiment of the utility model is derived from a high-stability quartz crystal calculated by software, and the output is very stable and will not drift due to temperature.

[0073] The single chip microcomputer circuit 1 includes a single chip microcomputer U1 and a single chip microcomputer power supply circuit 11 .

[0074] The single-chip computer power supply circuit 11 includes: a high-temperature power supply chip U2, a high-temperature tantalum chip capacitor E1 and a second resistor R2.

[0075] The positive pole of battery 2 is connected to the power input pin of the high-temperature power supply chip U2 and one end of the second resistor R2, and the other end of the second resistor R2 is connected to the enable pin of the high-temperature power supply chip U2; the 5V voltage output pin of the high-temperature power supply chip U2 is respectively connected to the positive pole of the high-temperature chip tantalum capacitor E1 and the VCC pin of the microcontroller U1; the PWM signal output pin of the microcontroller U1 is connected to the signal input end of the transformer oscillation circuit 4; the sampling current input pin of the microcontroller U1 is connected to the output end of the current sampling circuit 6; the sampling voltage input pin of the microcontroller U1 is connected to the output end of the voltage sampling circuit 7.

[0076] The high-temperature power supply chip U2 receives the voltage input of battery 2 and generates the 5V power supply required for the operation of the microcontroller U1. The high-temperature power supply chip U2 uses the high-temperature power supply chip TLE4476D, which is packaged in P-TO-252-5-1. The output voltage of the positive pole of battery 2 (5.7-42V) is input from pin 1 of the high-temperature power supply chip U2, and pin 4 outputs 5V voltage, which is provided to the microcontroller U1. Pin 3 is grounded and connected to the negative pole of battery 2.

[0077] The high-temperature chip tantalum capacitor E1 uses a 100U / 16V TPSB packaged high-temperature chip tantalum capacitor, and the second resistor R2 uses a 10KΩ 0805 packaged high-temperature chip resistor.

[0078] The single-chip microcomputer U1 uses the 8-pin micro high-temperature single-chip microcomputer PIC12F1822, SO8 package, which has PWM function and analog signal AD acquisition function. The control signal input pin of the single-chip microcomputer U1 receives the input of the control signal CTRL, which controls the single-chip microcomputer U1 to turn on the PWM function and start generating PWM signals.

[0079] It should be noted that the operation of the microcontroller U1 is controlled by a software program written into the microcontroller U1.

[0080] like Figure 3 FIG. 1 is a flowchart of a working process of a single chip microcomputer U1 disclosed in an embodiment of the present utility model.

[0081] First, the program initializes the port functions, initializes the PWM mode, and initializes the ADC data acquisition of the microcontroller. It then checks whether the input control signal CTRL is low, determining whether high-voltage output is enabled. If the control signal is low, high-voltage operation begins, with a PWM signal outputting a 40kHz frequency and a 5% duty cycle for 10 milliseconds. Due to the fixed low duty cycle, the startup current is low. After charging for 10 milliseconds, a certain high-voltage output is achieved, but not yet meeting the required level. The program then checks whether the current sampling signal ISAMP is greater than the threshold reference voltage. If so, it indicates a problem with the external circuitry or load, resulting in excessive current. PWM generation is then stopped, disabling high-voltage output and preserving battery charge. If the current sampling signal ISAMP is less than the threshold reference voltage, the program samples the high-voltage sampling signal VSAMP and outputs a PWM signal with varying duty cycles based on the sampled value, thereby controlling the output voltage.

[0082] Specifically, the output formula of duty cycle is:

[0083] D=(VREF-VSAMP) / VREF*20%

[0084] Among them, D represents the duty cycle, VSAMP represents the high-voltage sampling signal, and VREF represents the threshold reference voltage. It can be seen from the formula that when the high-voltage sampling signal is zero, the duty cycle is the largest. However, since a 5% duty cycle PWM signal is used to charge for 10 milliseconds at the beginning, a certain sampling voltage value has been reached, so the output duty cycle is not large. Generally, during normal operation, the current is stable. Once the high-voltage sampling signal is less than VREF, a PWM signal will be output. At this time, the duty cycle is generally very small, so during normal operation, there will be no sudden increase in current. The program sets the maximum duty cycle to 20%, which also limits the maximum output current from another aspect.

[0085] It should be noted that when the high-voltage generating circuit starts working, the microcontroller software controls the output frequency of 40K and the PWM signal of 5% duty cycle for 10 milliseconds. Although there is still a certain starting current at this time, it is much smaller than the duty cycle of the dedicated chip close to 100%, which will not cause excessive voltage drop of the battery voltage at startup, thus ensuring the normal operation of the storage instrument.

[0086] The transformer oscillator circuit 4 includes a transformer T1 , a MOS transistor N1 , a third resistor R3 , and a fourth resistor R4 .

[0087] One end of the primary side of the transformer T1 is connected to the positive electrode of the battery, and the other end of the primary side of the transformer T1 is connected to the drain of the MOS transistor N1; one end of the secondary side of the transformer T1 is connected to the input end of the voltage doubler output circuit 5, and the other end of the secondary side of the transformer T1 is grounded; the gate of the MOS transistor N1 is connected to one end of the third resistor R3, and the other end of the third resistor R3 is connected to the signal output end of the single-chip computer circuit 1; the source of the MOS transistor N1 is connected to one end of the fourth resistor R4, and the other end of the fourth resistor R4 is grounded.

[0088] Specifically, the PWM signal output by the single-chip microcomputer circuit 1 is sent to the gate of the MOS transistor N1 through the third resistor R3, controlling the transformer T1 to generate oscillation. One end of the primary side of the transformer is connected to the positive electrode of the battery 2, and the other end is connected to the drain of the MOS transistor N1. The source of the MOS transistor N1 is grounded through the fourth resistor R4.

[0089] In one embodiment, the current sampling circuit 6 includes: a third capacitor C3 and a fifth resistor R5,

[0090] One end of the fifth resistor R5 is connected to the source of the MOS transistor N1 , and the other end of the fifth resistor R5 is respectively connected to one end of the third capacitor C3 and the sampling current input end of the single chip circuit 1 ; the other end of the third capacitor C3 is grounded.

[0091] It should be noted that the current sampling circuit 6 samples and outputs a current sampling signal ISAMP, which is sent to the AD port of the microcontroller U1 (i.e., the sampling current input terminal of the microcontroller circuit 1) for analog data acquisition by the microcontroller U1. The third resistor R3 is a 100 ohm high-temperature chip resistor in a 0805 package. The fourth resistor R4 is a 0.25 ohm high-temperature chip resistor in a 0805 package. The fifth resistor R5 is a 10 kΩ high-temperature chip resistor in a 0805 package. The third capacitor C3 is a 1 uF high-temperature chip capacitor in a 0805 package. The transformer N1 is an IRFF430 transformer. The transformer T1 is a high-temperature pulse transformer with a 1:40 ratio. The MOS transistor N1 is a high-temperature N-channel MOS transistor.

[0092] Among them, the voltage doubler output circuit 5 includes: a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a sixth diode D6, a fourth capacitor C4, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, an eighth capacitor C8 and a ninth capacitor C9.

[0093] The anode of the first diode D1 is connected to one end of the fifth capacitor C5. The intersection between the anode of the first diode D1 and one end of the fifth capacitor C5 is connected to the output end of the transformer oscillation circuit 4 as an input end. The cathode of the first diode D1 is connected to one end of the fourth capacitor C4 and the anode of the second diode D2. The other end of the fourth capacitor C4 is grounded.

[0094] The anode of the second diode D2 is connected to one end of the sixth capacitor C6, and the cathode of the second diode D2 is connected to the other end of the fifth capacitor C5 and the anode of the third diode D3;

[0095] The anode of the third diode D3 is connected to one end of the seventh capacitor C7, and the cathode of the third diode D3 is connected to the other end of the sixth capacitor C6 and the anode of the fourth diode D4;

[0096] An anode of the fourth diode D4 is connected to one end of the eighth capacitor C8, and a cathode of the fourth diode D4 is connected to the other end of the seventh capacitor C7 and an anode of the fifth diode D5;

[0097] An anode of the fifth diode D5 is connected to one end of the ninth capacitor C9, and a cathode of the fifth diode D5 is connected to the other end of the eighth capacitor C8 and an anode of the sixth diode D6;

[0098] The cathode of the sixth diode D6 is connected to the other end of the ninth capacitor C9 , and the intersection point between the cathode of the sixth diode D6 and the ninth capacitor C9 is connected to the sampling end of the voltage sampling circuit 7 as an output end.

[0099] It should be noted that the voltage doubler output circuit 5 adopts a 6-fold voltage output circuit, each diode in the voltage doubler output circuit 5 uses a high-temperature chip diode RN2000E, and each capacitor in the voltage doubler output circuit 5 uses a 472 / 3000V high-temperature chip capacitor.

[0100] In one embodiment, the voltage sampling circuit 7 includes a potentiometer W1, a sixth resistor R6, and a tenth capacitor C10. One end of the sixth resistor R6 is connected to the output end of the voltage multiplier output circuit 5 and one end of the tenth capacitor C10; the other end of the sixth resistor R6 is connected to one end of the potentiometer W1, and the other end of the potentiometer W1 is connected to the other end of the tenth capacitor C10 and grounded; the adjustable end of the potentiometer W1 is connected to the sampling voltage input end of the single-chip microcomputer circuit 1.

[0101] It should be noted that the high-voltage sampling signal VSAMP is sent to the AD port of the microcontroller U17 pin (that is, the sampling voltage input terminal of the microcontroller circuit 1), the sixth resistor R6 is a 100 megohm high-temperature chip resistor in a 0805 package, and the potentiometer W1 is a 100 kiloohm high-temperature chip potentiometer in a chip package. By adjusting the potentiometer W1, the high-voltage output of the voltage doubler output circuit 5 can be adjusted. The tenth capacitor C10 is a 103 / 3000V capacitor in a high-temperature RAD0.4 package.

[0102] Based on the high-voltage generating circuit disclosed in the above-mentioned embodiment of the utility model, this solution uses a single-chip microcomputer to replace the traditional PWM control chip, and a quartz crystal to replace the traditional resistor-capacitor oscillation network to provide a stable clock signal for the single-chip microcomputer. The PWM signal for the transformer oscillation circuit is generated by the single-chip microcomputer. Because the operation of the single-chip microcomputer is controlled by a software program written into the single-chip microcomputer, the starting current can be reduced by limiting the duty cycle of the PWM signal output by the single-chip microcomputer at the circuit's initial operation.

[0103] Each embodiment in this specification is described in a progressive manner. The same or similar parts between the embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple. For relevant parts, refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. A person of ordinary skill in the art can understand and implement it without expending creative work.

[0104] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0105] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high voltage generating circuit, characterized in that: The high voltage generating circuit includes: a single chip microcomputer circuit, a battery, a quartz crystal oscillator circuit, a transformer oscillator circuit, a voltage doubling output circuit, a current sampling circuit and a voltage sampling circuit; The battery is connected to the single chip microcomputer circuit and the transformer oscillation circuit; The clock output terminal of the quartz crystal oscillator circuit is connected to the clock input terminal of the single-chip microcomputer circuit, and the feedback input terminal of the quartz crystal oscillator circuit is connected to the feedback terminal of the single-chip microcomputer circuit; The signal output end of the single chip microcomputer circuit is connected to the signal input end of the transformer oscillation circuit for inputting a PWM signal to the transformer oscillation circuit; The output end of the transformer oscillation circuit is connected to the input end of the voltage doubler output circuit; The sampling end of the current sampling circuit is connected to the transformer oscillation circuit, and the output end of the current sampling circuit is connected to the sampling current input end of the single chip microcomputer circuit; The sampling end of the voltage sampling circuit is connected to the output end of the voltage doubling output circuit, and the output end of the voltage sampling circuit is connected to the sampling voltage input end of the single chip microcomputer circuit.

2. The high voltage generating circuit according to claim 1, wherein: The quartz crystal oscillator circuit includes: a quartz crystal oscillator, a first capacitor, a second capacitor and a first resistor; The clock output end of the quartz crystal oscillator is respectively connected to the clock input end of the single-chip microcomputer circuit, one end of the first capacitor and one end of the first resistor; The feedback input end of the quartz crystal oscillator is respectively connected to the feedback end of the single chip microcomputer circuit, one end of the second capacitor and the other end of the first resistor; The other end of the first capacitor and the other end of the second capacitor are grounded.

3. The high voltage generating circuit according to claim 1, wherein: The single chip microcomputer circuit includes: a single chip microcomputer and a single chip microcomputer power supply circuit; The single chip computer power supply circuit includes: a high temperature power supply chip, a high temperature chip tantalum capacitor and a second resistor; The positive electrode of the battery is connected to the power input pin of the high-temperature power chip and one end of the second resistor, and the other end of the second resistor is connected to the enable pin of the high-temperature power chip; The 5V voltage output pin of the high-temperature power supply chip is connected to the positive electrode of the high-temperature tantalum chip capacitor and the VCC pin of the single-chip microcomputer respectively; The PWM signal output pin of the single chip microcomputer is connected to the signal input end of the transformer oscillation circuit; The sampling current input pin of the single chip microcomputer is connected to the output end of the current sampling circuit; The sampling voltage input pin of the single chip microcomputer is connected to the output end of the voltage sampling circuit.

4. The high voltage generating circuit according to claim 3, wherein: The single chip microcomputer includes: PIC12F1822 single chip microcomputer.

5. The high voltage generating circuit according to claim 3, wherein: The high-temperature power supply chip includes: a TLE4476D chip.

6. The high voltage generating circuit according to claim 3, wherein: The second resistor includes: a high-temperature chip resistor with a resistance of 10 kΩ and a 0805 package.

7. The high voltage generating circuit according to claim 1, wherein: The transformer oscillation circuit includes: a transformer, a MOS tube, a third resistor and a fourth resistor; One end of the primary side of the transformer is connected to the positive electrode of the battery, and the other end of the primary side of the transformer is connected to the drain of the MOS tube; One end of the secondary side of the transformer is connected to the input end of the voltage doubler output circuit, and the other end of the secondary side of the transformer is grounded; The gate of the MOS transistor is connected to one end of the third resistor, and the other end of the third resistor is connected to the signal output end of the single chip circuit; The source of the MOS transistor is connected to one end of the fourth resistor, and the other end of the fourth resistor is grounded.

8. The high voltage generating circuit according to claim 7, wherein: The current sampling circuit includes: a third capacitor and a fifth resistor; One end of the fifth resistor is connected to the source of the MOS transistor, and the other end of the fifth resistor is connected to one end of the third capacitor and the sampling current input end of the single chip microcomputer circuit respectively; The other end of the third capacitor is grounded.

9. The high voltage generating circuit according to claim 1, wherein: The voltage doubling output circuit includes: a first diode, a second diode, a third diode, a fourth diode, a fifth diode, a sixth diode, a fourth capacitor, a fifth capacitor, a sixth capacitor, a seventh capacitor, an eighth capacitor and a ninth capacitor; The anode of the first diode is connected to one end of the fifth capacitor, the intersection between the anode of the first diode and one end of the fifth capacitor is connected to the output end of the transformer oscillation circuit as an input end, the cathode of the first diode is connected to one end of the fourth capacitor and the anode of the second diode, and the other end of the fourth capacitor is grounded; An anode of the second diode is connected to one end of the sixth capacitor, and a cathode of the second diode is connected to the other end of the fifth capacitor and the anode of the third diode; The anode of the third diode is connected to one end of the seventh capacitor, and the cathode of the third diode is connected to the other end of the sixth capacitor and the anode of the fourth diode; The anode of the fourth diode is connected to one end of the eighth capacitor, and the cathode of the fourth diode is connected to the other end of the seventh capacitor and the anode of the fifth diode; The anode of the fifth diode is connected to one end of the ninth capacitor, and the cathode of the fifth diode is connected to the other end of the eighth capacitor and the anode of the sixth diode; The cathode of the sixth diode is connected to the other end of the ninth capacitor, and the intersection point between the cathode of the sixth diode and the ninth capacitor is connected to the sampling end of the voltage sampling circuit as an output end.

10. The high voltage generating circuit according to claim 1, wherein: The voltage sampling circuit includes: a potentiometer, a sixth resistor and a tenth capacitor; One end of the sixth resistor is connected to the output end of the voltage doubler output circuit and one end of the tenth capacitor; The other end of the sixth resistor is connected to one end of the potentiometer, and the other end of the potentiometer is connected to the other end of the tenth capacitor and is grounded; The adjustable end of the potentiometer is connected to the sampling voltage input end of the single chip microcomputer circuit.

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