Soft switching high-voltage power supply system with adjustable output

Abstract

The utility model provides a soft switching high-voltage power supply system with adjustable output. The soft switching high-voltage power supply system comprises a half-bridge conversion circuit, a transformer T3, an output rectification filter circuit, a secondary side overcurrent and current detection circuit, an isolation drive circuit, a micro-control unit, an overcurrent protection circuit and a primary side sampling circuit, the half-bridge conversion circuit is connected to commercial power and is electrically connected with the transformer T3 and the primary side sampling circuit, the transformer T3 is electrically connected with the output rectification filter circuit, and the output rectification filter circuit is electrically connected with the secondary side overcurrent and current detection circuit. The secondary side overcurrent and current detection circuit is electrically connected with the isolation driving circuit and the micro-control unit, the isolation driving circuit is electrically connected with the half-bridge conversion circuit and the micro-control unit, the side current and voltage detection circuit can perform real-time detection until the detected voltage reaches a set voltage, when the detected voltage is higher than the set voltage, the frequency is increased, and the frequency is reduced. And automatic voltage stabilization is realized.

Description

Technical Field

[0001] The utility model relates to the technical field of high-voltage power supplies, in particular to a soft-switch high-voltage power supply system with adjustable output. Background Art

[0002] While the urban agglomeration effect brings economic development, people's diversified lifestyles also cause air pollution, such as fume pollution in the production and living processes of large shopping malls, food courts, barbecue restaurants, food processing plants, etc. Therefore, low-current high-voltage electricity uses electric fields to ionize and remove dust from the polluted air, and fume purification is still the most effective. Due to long-term use, the electric field will short-circuit or the insulation resistance will decrease due to polluted gases and moisture. At present, the high-voltage power supply controlled by traditional analog chips will only flash and restart after the electric field fails, so it does not play a role in purifying the fault. It requires special personnel to check regularly (regardless of whether the equipment has a fault or not), which wastes a lot of manpower and material resources.

[0003] In view of this, it is necessary to provide a new type of output adjustable soft switching high voltage power supply system to overcome the above defects. Utility Model Content

[0004] The purpose of the utility model is to provide a soft-switching high-voltage power supply system with adjustable output, which can detect the voltage until it reaches the set voltage, and the secondary side overcurrent and current detection circuit are detected in real time. When the detection voltage is higher than the set voltage, the frequency is increased to achieve automatic voltage stabilization, and no special person is required to inquire regularly, saving labor costs.

[0005] In order to achieve the above-mentioned object, the utility model provides a soft-switching high-voltage power supply system with adjustable output, including: a half-bridge conversion circuit, a transformer T3, an output rectifier filter circuit, a secondary side overcurrent and current detection circuit, an isolation drive circuit, a microcontroller unit, a secondary side current and voltage amplification circuit, an overcurrent protection circuit and a primary side sampling circuit;

[0006] The half-bridge conversion circuit is connected to the mains and is electrically connected to the transformer T3 and the primary sampling circuit. The transformer T3 is electrically connected to the output rectifier and filter circuit. The output rectifier and filter circuit is electrically connected to the secondary overcurrent and current detection circuit and the secondary current and voltage amplification circuit. The secondary overcurrent and current detection circuit is electrically connected to the isolation drive circuit and the micro control unit. The secondary current and voltage amplification circuit is electrically connected to the micro control unit. The isolation drive circuit is electrically connected to the half-bridge conversion circuit and the micro control unit.

[0007] Preferably, the half-bridge conversion circuit includes a capacitor C101, a diode D22, a resistor R38, a resistor R40, a resistor R155, a MOS tube M1, a MOS tube M2, a resistor R108, a resistor R52, a resistor R47, a diode D27, a capacitor C45, a capacitor C47 and a capacitor C48;

[0008] The positive electrode of the capacitor C101, the drain of the MOS tube M1 and the capacitor C45 are electrically connected to the mains, the gate of the MOS tube M1 is electrically connected to the resistor R155, the resistor R38 and the resistor R40, the resistor R40 is electrically connected to the anode of the diode D22, the cathode of the diode D22 is electrically connected to the resistor R38 and the isolation drive circuit, and the resistor R155 is also electrically connected to the isolation drive circuit.

[0009] The source of the MOS tube M1 is electrically connected to the resistor R155 and the drain of the MOS tube M2, the gate of the MOS tube M2 is electrically connected to the resistors R108, R52 and R47, the resistor R108 is electrically connected to the source of the MOS tube M2, the negative electrode of the capacitor C101 and the capacitor C47, the negative electrode of the capacitor C101 is grounded, the resistor R52 is electrically connected to the anode of the diode D27, the cathode of the diode D27 is electrically connected to the resistor R47 and the isolation drive circuit, the capacitor C45 is electrically connected to the capacitor C48 and the capacitor C47, the capacitor C48 is electrically connected to the T-1 end of the winding N1 of the transformer T3, and the source of the MOS tube M1 is electrically connected to the current transformer LT1 of the primary side sampling circuit.

[0010] Preferably, the output rectifier filter circuit includes capacitor C18, capacitor C17, capacitor C14, diode D7m, capacitor C15, capacitor C19, capacitor C20, diode D5m, capacitor C13, capacitor C8, capacitor C7, diode D6m, capacitor C21, capacitor C22, capacitor C16, capacitor C26, diode D4m, resistor R1, resistor R2, resistor R3, inductor L1, inductor L2 and inductor L3;

[0011] The first end of the capacitor C18, the first end of the capacitor C17, and the first end of the capacitor C14 are electrically connected to the ZL end of the winding N2 of the transformer T3, the second end of the capacitor C18, the second end of the capacitor C17, and the second end of the capacitor C14 are electrically connected to the anode of the diode D7m, the cathode of the diode D7m, the first end of the capacitor C15, the first end of the capacitor C19, and the first end of the capacitor C20 are electrically connected to the DC-end of the winding N2 of the transformer T3, the second end of the capacitor C15, the second end of the capacitor C19, and the second end of the capacitor C20 are electrically connected to the anode of the diode D5m,

[0012] The cathode of the diode D5m is electrically connected to the anode of the diode D7m, the first end of the capacitor C13, the first end of the capacitor C8, the first end of the capacitor C7, and the anode of the diode D6m; the cathode of the diode D6m is electrically connected to the anode of the diode D5m, the first end of the capacitor C21, and the first end of the capacitor C22; the second end of the capacitor C21 is electrically connected to the first end of the capacitor C16 and the first end of the capacitor C26; the second end of the capacitor C22 is electrically connected to the second end of the capacitor C16 and the second end of the capacitor C26; the second ends of the capacitor C16 and the capacitor C26 are electrically connected to the anode of the diode D4m; the cathode of the diode D4m is electrically connected to the anode of the diode D6m;

[0013] The first end of the resistor R1, the first end of the resistor R2, and the first end of the resistor R3 are electrically connected to the anode of the diode D4m, the second end of the resistor R1, the second end of the resistor R2, and the second end of the resistor R3 are electrically connected to the first end of the inductor L1, the first end of the inductor L2, and the first end of the inductor L3, respectively, and the second end of the inductor L1, the second end of the inductor L2, and the second end of the inductor L3 are electrically connected to each other.

[0014] Preferably, the isolation driving circuit includes an isolation driving chip U3, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1, a resistor R6, a resistor R3, a diode D17, a capacitor C14, a capacitor C13 and a capacitor C32;

[0015] The VIA pin of the isolation driver chip U3 is electrically connected to the resistor R1, the resistor R1 is electrically connected to the resistor R4 and the DV1 end of the micro control unit, the resistor R4 is grounded, the VIB pin of the isolation driver chip U3 is electrically connected to the resistor R2, the resistor R2 is electrically connected to the resistor R5 and the DV2 end of the micro control unit, the resistor R5 is grounded, the VDDI pin of the isolation driver chip U3 is electrically connected to the capacitor C1 and the external power supply VCC-I, the capacitor C1 is grounded and electrically connected to the NC pin of the isolation driver chip U3 and the GNDI pin of the isolation driver chip U3, the DIS pin of the isolation driver chip U3 is electrically connected to the resistor R6 and the overcurrent protection circuit, the DT pin of the isolation driver chip U3 is electrically connected to the resistor R3, the resistor R6 is electrically connected to the resistor R3 and grounded,

[0016] The VDDA pin of the isolation driver chip U3 is electrically connected to the first end of the capacitor C14, the first end of the capacitor C13 and the external power supply VDD, the second end of the capacitor C14, the second end of the capacitor C13 are electrically connected to the VDDBI pin of the isolation driver chip U3 and the resistor R155, the VOA pin of the isolation driver chip U3 is electrically connected to the cathode of the diode D22, the VDDB pin of the isolation driver chip U3 is electrically connected to the anode of the diode D17 and connected to the external power supply VDD, the cathode of the diode D17 is electrically connected to the VDDA pin of the isolation driver chip U3, the pin VOB of the isolation driver chip U3 is electrically connected to the resistor R47, the GNDB pin of the isolation driver chip U3 is electrically connected to the capacitor C32, and the capacitor C32 is electrically connected to the external power supply VDD.

[0017] Preferably, the primary current sampling circuit includes a current transformer LT1, a resistor R84, a diode D11, a diode D4, a diode D5, a diode D8, a resistor R73 and a capacitor C26; the T-2 end of the coil one of the current transformer LT1 is electrically connected to the T-2 end of the winding N1 of the transformer T3, the HB end of the current transformer LT1 is electrically connected to the resistor R155, the first end of the coil two of the current transformer LT1 is electrically connected to the first end of the resistor R84, the cathode of the diode D11 and the anode of the diode D4, the second end of the coil two of the current transformer LT1 is electrically connected to the second end of the resistor R84, the cathode of the diode D5 and the anode of the diode D8, the cathode of the diode D4 and the cathode of the diode D8 are electrically connected to the first end of the resistor R73 and the first end of the capacitor C26, the second end of the resistor R73 and the second end of the capacitor C26 are electrically connected to the anode of the diode D11 and the anode of the diode D5.

[0018] Preferably, the overcurrent protection circuit includes a resistor R23, a resistor R58, a resistor R36, a resistor R16, a capacitor C41, a comparator U7A, a capacitor C17, a resistor R19, a resistor R77, a capacitor C20, a resistor R54, a resistor R53, a resistor R56, a resistor R51, a capacitor C21, a comparator U7B and a capacitor C23;

[0019] The first end of the resistor R23 is electrically connected to the resistor R73 of the primary current sampling circuit, the first end of the resistor R58, the first end of the capacitor C41 and the same-direction input end of the comparator U7A are electrically connected to the second end of the resistor R23, the resistor R36 is externally connected to a 5V power supply, the second end of the resistor R36 is electrically connected to the first end of the resistor R16 and the reverse input end of the comparator U7A, the second end of the resistor R58, the second end of the resistor R16 and the second end of the capacitor C41 are electrically connected,

[0020] The positive electrode of the comparator U7A is electrically connected to a 5V external power supply and to a first end of a capacitor C17, the second end of the capacitor C17 is grounded, the negative electrode of the comparator U7A is grounded, the output end of the comparator is electrically connected to a first end of a resistor R19 and a DIS pin of an isolation driver chip, the second end of the resistor R19 is electrically connected to a first end of the capacitor C17 and a first end of a resistor R77, the second end of the resistor R77 is electrically connected to an output end of the comparator U7B, a micro control unit, and a first end of a capacitor C23,

[0021] The second end of the capacitor C23 is electrically connected to the same-direction input end of the comparator U7B, the first end of the capacitor C21, the first end of the resistor R51, and the first end of the resistor R56. The second end of the capacitor C21 is electrically connected to the second end of the resistor R56 and is grounded. The second end of the resistor R51 is electrically connected to the resistor R73. The reverse input end of the comparator U7B is electrically connected to the first end of the resistor R53. The second end of the resistor R53 is electrically connected to the first end of the resistor R54, the first end of the capacitor C20, and the micro control unit. The second end of the resistor R54 is electrically connected to the second end of the capacitor C20 and is grounded.

[0022] Preferably, the secondary current and voltage amplification circuit includes a voltage amplification unit and a current amplification unit, and the voltage amplification unit includes a resistor R81, a capacitor C37, a capacitor C27, a diode D33, a diode D34, a resistor R65, a variable resistor RP6, a resistor R60, an operational amplifier U9A, a capacitor C25, a resistor R59, a resistor R85 and a capacitor C28;

[0023] The first end of the resistor R81 is electrically connected to the resistor R155 of the half-bridge conversion circuit, the first end of the capacitor C37 and the first end of the resistor R64, the second end of the resistor R81 is electrically connected to the second end of the capacitor C37 and is grounded, the second end of the resistor R64 is electrically connected to the first end of the capacitor C27, the cathode of the diode D33, the anode of the diode D34 and the first end of the resistor R65, the second end of the capacitor C27 is electrically connected to the second end of the capacitor C37, the anode of the diode D33, the cathode of the diode D34, the same-direction input end of the operational amplifier U9A, the negative terminal of the operational amplifier U9A, the first end of the resistor R85 and the first end of the capacitor C28 and is grounded, the second end of the resistor R65 is electrically connected to the first end of the variable resistor RP6 and the reverse input end of the operational amplifier U9A, the positive terminal of the operational amplifier U9A is connected to the external power supply of 12V and is electrically connected to the first end of the capacitor C25, and the second end of the capacitor C25 is grounded,

[0024] The second end of the variable resistor RP6 is electrically connected to the first end of the resistor R59 and the output end of the operational amplifier U9A. The second end of the resistor R59 is electrically connected to the second end of the resistor R85, the second end of the capacitor C28 and the micro control unit.

[0025] Preferably, the current amplifying unit includes a resistor R15, a resistor R17, a diode D6, a diode D7, a capacitor C3, a resistor R18, an operational amplifier U9B, a resistor R21, a capacitor C5, a resistor R22, a capacitor C6 and a resistor R2; a first end of the resistor R15 is grounded, and a second end of the resistor R15 is electrically connected to the diode D6, the diode D7, a first end of the capacitor C3, a reverse input end (-) of the operational amplifier U9B and a first end of the resistor R18.

[0026] The first end of the resistor R17 is electrically connected to the secondary overcurrent and current detection circuit, the second end of the resistor R17 is electrically connected to the anode of the diode D6, the cathode of the diode D7, the second end of the capacitor C3 and the same-direction input terminal (+) of the operational amplifier U9B, the output end of the operational amplifier U9B is electrically connected to the second end of the resistor R18 and the first end of the resistor R21, the second end of the resistor R21 is electrically connected to the first end of the capacitor C5 and the first end of the resistor R22, the second end of the capacitor C5 is grounded, the second end of the resistor R22 is electrically connected to the first end of the capacitor C6, the first end of the resistor R25 and the micro control unit, and the second end of the resistor R25 is electrically connected to the second end of the capacitor C6 and the second end of the capacitor C5.

[0027] Preferably, the secondary side overcurrent and current detection circuit includes a current transformer LT2, a capacitor C10, a three-terminal regulator U23, a capacitor C33, a resistor R33, a resistor R31, a thyristor SR1, a resistor R32, a resistor R79, a diode D13, a diode D15, a diode D12, a diode D14, and a resistor R72;

[0028] The positive electrode of the capacitor C10 is connected to the external power supply 12 and is electrically connected to the pin IN of the three-terminal regulator U23. The negative electrode of the capacitor C10 is electrically connected to the GND pin of the three-terminal regulator U23 and is grounded. The OUT pin of the three-terminal regulator U23 is electrically connected to the external power supply of 5V, the resistor R33 and the positive electrode of the capacitor C33. The negative electrode of the capacitor C33 is electrically connected to the GND pin of the three-terminal regulator U23.

[0029] The resistor R33 is electrically connected to the resistor R31 and the anode of the thyristor SR1. The resistor R31 is electrically connected to the external power supply VCC-I. The cathode of the thyristor SR1 is electrically connected to the first end of the resistor R29, the first end of the capacitor C8, the first end of the resistor R79, the anode of the diode D15 and the anode of the diode D14. The control electrode of the thyristor SR1 is electrically connected to the second end of the resistor R29, the second end of the capacitor C8 and the first end of the resistor R32.

[0030] The second end of the resistor R32 is electrically connected to the second end of the resistor R79, the cathode of the diode D13 and the cathode of the diode D12, the cathode of the diode D15 is electrically connected to the anode of the diode D13, the first end of the resistor R72 and one end of the coil two of the current transformer LT2, the cathode of the diode D14 is electrically connected to the anode of the diode D12, the resistor R72 and the other end of the coil two of the current transformer LT2, one end of the coil one of the current transformer LT2 is electrically connected to the DC-end of the winding N2 of the transformer T3, the other end of the coil one of the current transformer LT2 is electrically connected to the micro control unit and the resistor R30, the resistor R30 is electrically connected to the resistor R17 and the resistor R30A of the secondary current and voltage amplifier circuit, and the resistor R30A is grounded.

[0031] Compared with the prior art, the beneficial effects are: 1) when the micro control unit outputs PWM1 signal and PWM2 signal to the isolation drive circuit, the half-bridge conversion circuit is turned on, and the DC square wave of about 300V is boosted through the isolation transformer T3. The phase difference between the PWM1 signal and the PWM2 signal is 180 degrees. The duty cycle is gradually increased, and the single-sided modulation is adjusted to 49.5%. The voltage is detected and compared with the set voltage. If the voltage is not enough (not reaching the set value), the frequency is reduced in steps of 500Hz until the detection voltage reaches the set voltage. The minimum frequency is limited to 16K Hz. The secondary side overcurrent and current detection circuit detects in real time. When the detection voltage is higher than the set voltage, the frequency is increased to achieve automatic voltage stabilization. There is no need for special personnel to inquire regularly, saving labor costs.

[0032] 2) The present invention utilizes MCU to communicate with the computer while controlling the operation of the power supply, and then sends the power supply working status to the computer for display through the Internet of Things (Internet), so as to achieve real-time monitoring, control, and recording of the power supply status. The system allows the power supply to be controlled or operated remotely to achieve the purpose of reducing manpower.

[0033] Other features and advantages of the utility model will be stated in the following description, and some will be apparent from the description, or can be understood through the implementation of the utility model. The features and advantages of the utility model can be realized and obtained by the elements and combinations specifically pointed out in the attached application scope. These and other features of the utility model will become more clearly understood according to the following description and the attached claims, or can be understood through the implementation of the embodiments described in the utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.

[0035] Figure 1 The utility model provides a block diagram of the principle of a soft-switching high-voltage power supply system with adjustable output.

[0036] Figure 2 for Figure 1 The circuit diagram of the half-bridge converter circuit is shown.

[0037] Figure 3 for Figure 1 The circuit diagram of the transformer is shown.

[0038] Figure 4 for Figure 1 The circuit diagram of the output rectifier and filter circuit is shown.

[0039] Figure 5 for Figure 1 The circuit schematic diagram of the isolated driving circuit is shown.

[0040] Figure 6 for Figure 1 The circuit diagram of the primary current sampling circuit is shown.

[0041] Figure 7 for Figure 1 The circuit schematic diagram of the overcurrent protection circuit is shown.

[0042] Figure 8 for Figure 1 The circuit diagram of the secondary side overcurrent and current detection circuit is shown.

[0043] Fig. 9 for Figure 1 The circuit diagram of the secondary side voltage and current amplifier circuit is shown. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and beneficial technical effect of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. It should be understood that the specific implementation methods described in this specification are only for explaining the utility model, and are not intended to limit the utility model.

[0045] It should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0046] It should also be noted that, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix", "set" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this utility model can be determined according to the specific circumstances.

[0047] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first", "second", and "third" may explicitly or implicitly include one or more of the features. In addition, the meaning of "multiple" and "several" refers to two or more, unless otherwise clearly and specifically defined.

[0048] See also Figures 1 to 9 The utility model provides a soft-switching high-voltage power supply system with adjustable output, including: a half-bridge conversion circuit, a transformer T3, an output rectifier filter circuit, a secondary overcurrent and current detection circuit, an isolation drive circuit, a microcontroller unit, a secondary current and voltage amplification circuit, an overcurrent protection circuit and a primary sampling circuit;

[0049] The half-bridge conversion circuit is connected to the mains and is electrically connected to the transformer T3 and the primary sampling circuit. The transformer T3 is electrically connected to the output rectifier and filter circuit. The output rectifier and filter circuit is electrically connected to the secondary overcurrent and current detection circuit and the secondary current and voltage amplification circuit. The secondary overcurrent and current detection circuit is electrically connected to the isolation drive circuit and the micro control unit. The secondary current and voltage amplification circuit is electrically connected to the micro control unit. The isolation drive circuit is electrically connected to the half-bridge conversion circuit and the micro control unit. The micro control unit is electrically connected to an external computer through the MCU main control line.

[0050] Thus, when the microcontroller unit outputs PWM1 signal and PWM2 signal (two PWM waves with a maximum frequency of 40KHz and a minimum duty cycle of 1%) to the isolation drive circuit, the half-bridge conversion circuit is turned on, and the DC square wave of about 300V is boosted through the isolation transformer T3. The phase difference between the PWM1 signal and the PWM2 signal is 180 degrees. The duty cycle is gradually increased, and the single-sided modulation is adjusted to 49.5%. The voltage is detected and compared with the set voltage. If the voltage is not enough (not reaching the set value), the frequency is reduced in steps of 500Hz until the detection voltage reaches the set voltage. The minimum frequency is limited to 16K Hz. The secondary side overcurrent and current detection circuit detects in real time. When the detection voltage is higher than the set voltage, the frequency is increased to achieve automatic voltage stabilization.

[0051] It should be noted that, in this embodiment, the model of the microcontroller unit is STM32F103, which is mainly responsible for PWM signal output, voltage setting, controlling the output waveform pulse width and frequency adjustment according to the current and voltage detection circuit, controlling the PWM signal to be turned on or off according to the collected over-current protection, and is responsible for fault alarm display, determining the address code (or power supply number) and other functions.

[0052] In a preferred embodiment, the half-bridge conversion circuit includes a capacitor C101, a diode D22, a resistor R38, a resistor R40, a resistor R155, a MOS tube M1, a MOS tube M2, a resistor R108, a resistor R52, a resistor R47, a diode D27, a capacitor C45, a capacitor C47 and a capacitor C48;

[0053] The positive electrode of the capacitor C101, the drain of the MOS tube M1 and the capacitor C45 are electrically connected to the mains, the gate of the MOS tube M1 is electrically connected to the resistor R155, the resistor R38 and the resistor R40, the resistor R40 is electrically connected to the anode of the diode D22, the cathode of the diode D22 is electrically connected to the resistor R38 and the isolation drive circuit, and the resistor R155 is also electrically connected to the isolation drive circuit.

[0054] The source of the MOS tube M1 is electrically connected to the resistor R155 and the drain of the MOS tube M2, the gate of the MOS tube M2 is electrically connected to the resistors R108, R52 and R47, the resistor R108 is electrically connected to the source of the MOS tube M2, the negative electrode of the capacitor C101 and the capacitor C47, the negative electrode of the capacitor C101 is grounded, the resistor R52 is electrically connected to the anode of the diode D27, the cathode of the diode D27 is electrically connected to the resistor R47 and the isolation drive circuit, the capacitor C45 is electrically connected to the capacitor C48 and the capacitor C47, the capacitor C48 is electrically connected to the T-1 end of the winding N1 of the transformer T3, and the source of the MOS tube M1 is electrically connected to the current transformer LT1 of the primary side sampling circuit.

[0055] In this way, the 15V square wave signal sent by the isolation drive circuit is alternately given at the drive level Ho and Vs end of the MOS tube M1, and the drive level Lo and GND end of the MOS tube M2, so that the MOS tube M1 and the MOS tube M2 send the 300V DC to the transformer T3 through the capacitor C48, the resistor R38 and the resistor R47 are the gate drive resistors of the MOS tube M1 and the MOS tube M2 respectively, the resistor R40 and the diode D22 form the fast shutdown circuit of the MOS tube M1, and the resistor R52 and the diode D27 form the fast shutdown circuit of the MOS tube M2. When the square wave signal ends, the tail time is reduced and the loss is reduced. The resistor R155 and the resistor R108 are the discharge resistors, the capacitor C45 and the capacitor C47 are the bridge arm capacitors, and the capacitor C45, the capacitor C47 and the capacitor C48 and the leakage inductance of the transformer T3 form a resonant network.

[0056] In a preferred embodiment, Figure 2 As shown, transformer T3 has three windings, of which N1 is the main winding, which is the input end of the transformer and connected to the half-bridge conversion circuit, N2 is the high-voltage output winding, connected to the output rectifier filter circuit, and N3 is the other power supply winding. The isolation voltage between N1, N3 and N2 is 20KV, and the isolation voltage between N1 and N3 is 1.5KV.

[0057] In a preferred embodiment, the output rectifier filter circuit includes capacitor C18, capacitor C17, capacitor C14, diode D7m, capacitor C15, capacitor C19, capacitor C20, diode D5m, capacitor C13, capacitor C8, capacitor C7, diode D6m, capacitor C21, capacitor C22, capacitor C16, capacitor C26, diode D4m, resistor R1, resistor R2, resistor R3, inductor L1, inductor L2 and inductor L3;

[0058] The first end of the capacitor C18, the first end of the capacitor C17, and the first end of the capacitor C14 are electrically connected to the ZL end of the winding N2 of the transformer T3, the second end of the capacitor C18, the second end of the capacitor C17, and the second end of the capacitor C14 are electrically connected to the anode of the diode D7m, the cathode of the diode D7m, the first end of the capacitor C15, the first end of the capacitor C19, and the first end of the capacitor C20 are electrically connected to the DC-end of the winding N2 of the transformer T3, the second end of the capacitor C15, the second end of the capacitor C19, and the second end of the capacitor C20 are electrically connected to the anode of the diode D5m,

[0059] The cathode of the diode D5m is electrically connected to the anode of the diode D7m, the first end of the capacitor C13, the first end of the capacitor C8, the first end of the capacitor C7, and the anode of the diode D6m; the cathode of the diode D6m is electrically connected to the anode of the diode D5m, the first end of the capacitor C21, and the first end of the capacitor C22; the second end of the capacitor C21 is electrically connected to the first end of the capacitor C16 and the first end of the capacitor C26; the second end of the capacitor C22 is electrically connected to the second end of the capacitor C16 and the second end of the capacitor C26; the second ends of the capacitor C16 and the capacitor C26 are electrically connected to the anode of the diode D4m; the cathode of the diode D4m is electrically connected to the anode of the diode D6m;

[0060] The first end of the resistor R1, the first end of the resistor R2, and the first end of the resistor R3 are electrically connected to the anode of the diode D4m, the second end of the resistor R1, the second end of the resistor R2, and the second end of the resistor R3 are electrically connected to the first end of the inductor L1, the first end of the inductor L2, and the first end of the inductor L3, respectively, and the second end of the inductor L1, the second end of the inductor L2, and the second end of the inductor L3 are electrically connected to each other.

[0061] In a preferred embodiment, the isolation driving circuit includes an isolation driving chip U3, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1, a resistor R6, a resistor R3, a diode D17, a capacitor C14, a capacitor C13 and a capacitor C32;

[0062] The VIA pin of the isolation driver chip U3 is electrically connected to the resistor R1, the resistor R1 is electrically connected to the resistor R4 and the DV1 end of the micro control unit, the resistor R4 is grounded, the VIB pin of the isolation driver chip U3 is electrically connected to the resistor R2, the resistor R2 is electrically connected to the resistor R5 and the DV2 end of the micro control unit, the resistor R5 is grounded, the VDDI pin of the isolation driver chip U3 is electrically connected to the capacitor C1 and the external power supply VCC-I, the capacitor C1 is grounded and electrically connected to the NC pin of the isolation driver chip U3 and the GNDI pin of the isolation driver chip U3, the DIS pin of the isolation driver chip U3 is electrically connected to the resistor R6 and the overcurrent protection circuit, the DT pin of the isolation driver chip U3 is electrically connected to the resistor R3, the resistor R6 is electrically connected to the resistor R3 and grounded,

[0063] The VDDA pin of the isolation driver chip U3 is electrically connected to the first end of the capacitor C14, the first end of the capacitor C13 and the external power supply VDD, the second end of the capacitor C14, the second end of the capacitor C13 are electrically connected to the VDDBI pin of the isolation driver chip U3 and the resistor R155, the VOA pin of the isolation driver chip U3 is electrically connected to the cathode of the diode D22, the VDDB pin of the isolation driver chip U3 is electrically connected to the anode of the diode D17 and connected to the external power supply VDD, the cathode of the diode D17 is electrically connected to the VDDA pin of the isolation driver chip U3, the pin VOB of the isolation driver chip U3 is electrically connected to the resistor R47, the GNDB pin of the isolation driver chip U3 is electrically connected to the capacitor C32, and the capacitor C32 is electrically connected to the external power supply VDD.

[0064] In this way, DV1 is the PWM1 signal input terminal, DV2 is the PWM2 signal input terminal, resistors R1 and R2 are input resistors, resistors R4 and R5 are input terminals to filter out interference, when the VCC-I voltage is lower than 3V, the PWM1 signal and the PWM2 signal are under-voltage shutoff, capacitor C1 is the primary power supply capacitor with under-voltage shutoff, the DIS signal is set high to shut down the PWM1 signal and the PWM2 signal, the output diode D17 is a bootstrap power supply diode, capacitors C13, C14, and C32 are power supply capacitors.

[0065] In a preferred embodiment, the primary current sampling circuit includes a current transformer LT1, a resistor R84, a diode D11, a diode D4, a diode D5, a diode D8, a resistor R73 and a capacitor C26; the T-2 end of the coil 1 of the current transformer LT1 is electrically connected to the T-2 end of the winding N1 of the transformer T3, the HB end of the current transformer LT1 is electrically connected to the resistor R155, the first end of the coil 2 of the current transformer LT1 is electrically connected to the first end of the resistor R84, the cathode of the diode D11 and the anode of the diode D4, the second end of the coil 2 of the current transformer LT1 is electrically connected to the second end of the resistor R84, the cathode of the diode D5 and the anode of the diode D8, the cathode of the diode D4 and the cathode of the diode D8 are electrically connected to the first end of the resistor R73 and the first end of the capacitor C26, and the second end of the resistor R73 and the second end of the capacitor C26 are electrically connected to the anode of the diode D11 and the anode of the diode D5.

[0066] In this way, the current transformer LT1 is connected in series to the half-bridge conversion circuit. When the transformer T3 flows through the forward current and the reverse current, the current can be detected. After being amplified by the current transformer LT1, it is converted into a voltage signal and sent to the overcurrent protection circuit.

[0067] In a preferred embodiment, the overcurrent protection circuit includes a resistor R23, a resistor R58, a resistor R36, a resistor R16, a capacitor C41, a comparator U7A, a capacitor C17, a resistor R19, a resistor R77, a capacitor C20, a resistor R54, a resistor R53, a resistor R56, a resistor R51, a capacitor C21, a comparator U7B and a capacitor C23;

[0068] The first end of the resistor R23 is electrically connected to the resistor R73 of the primary current sampling circuit, the first end of the resistor R58, the first end of the capacitor C41 and the same-direction input terminal (+) of the comparator U7A are electrically connected to the second end of the resistor R23, the resistor R36 is externally connected to a 5V power supply, the second end of the resistor R36 is electrically connected to the first end of the resistor R16 and the reverse input terminal (-) of the comparator U7A, the second end of the resistor R58, the second end of the resistor R16 and the second end of the capacitor C41 are electrically connected,

[0069] The positive electrode of the comparator U7A is electrically connected to a 5V external power supply and to a first end of a capacitor C17, the second end of the capacitor C17 is grounded, the negative electrode of the comparator U7A is grounded, the output end of the comparator is electrically connected to a first end of a resistor R19 and a DIS pin of an isolation driver chip, the second end of the resistor R19 is electrically connected to a first end of the capacitor C17 and a first end of a resistor R77, the second end of the resistor R77 is electrically connected to an output end of the comparator U7B, a micro control unit, and a first end of a capacitor C23,

[0070] The second end of the capacitor C23 is electrically connected to the same-direction input terminal (+) of the comparator U7B, the first end of the capacitor C21, the first end of the resistor R51 and the first end of the resistor R56, the second end of the capacitor C21 is electrically connected to the second end of the resistor R56 and is grounded, the second end of the resistor R51 is electrically connected to the resistor R73, the reverse input terminal (-) of the comparator U7B is electrically connected to the first end of the resistor R53, the second end of the resistor R53 is electrically connected to the first end of the resistor R54, the first end of the capacitor C20 and the micro control unit, and the second end of the resistor R54 is electrically connected to the second end of the capacitor C20 and is grounded.

[0071] Among them, D-FT and R-FT are given signals, and one of them can be selected to be electrically connected to the micro control unit. Taking the given signal D-FT as an example, the given signal D-FT is transmitted to the reverse input terminal of the comparator U7B through the connector P7 and the resistor R53. The current sampling signal II is a pulse signal, which is divided by the resistor R51 and the resistor R56 and sent to the same-direction input terminal of the comparator U7B. When the voltage signal of the same-direction input terminal is higher than the given signal voltage of the reverse input terminal, the comparator output VCY is set high and the output 5V square wave high level is sent to the micro control unit. The capacitor C21 is a high-frequency peak filter to reduce interference signals and reduce the sensitivity of the comparator U7B. The current sampling signal II is simultaneously transmitted to the comparator U7B. When the voltage of the same-phase input terminal (+) of the comparator U7A is higher than the voltage of the reverse input terminal (-) of the comparator U7A, DIS is set high to shut down the circuit of the isolation driver chip U3.

[0072] In a preferred embodiment, the secondary current and voltage amplification circuit includes a voltage amplification unit and a current amplification unit, and the voltage amplification unit includes a resistor R81, a capacitor C37, a capacitor C27, a diode D33, a diode D34, a resistor R65, a variable resistor RP6, a resistor R60, an operational amplifier U9A, a capacitor C25, a resistor R59, a resistor R85 and a capacitor C28;

[0073] The first end of the resistor R81 is electrically connected to the resistor R155 of the half-bridge conversion circuit, the first end of the capacitor C37 and the first end of the resistor R64, the second end of the resistor R81 is electrically connected to the second end of the capacitor C37 and is grounded, the second end of the resistor R64 is electrically connected to the first end of the capacitor C27, the cathode of the diode D33, the anode of the diode D34 and the first end of the resistor R65, the second end of the capacitor C27 is electrically connected to the second end of the capacitor C37, the anode of the diode D33, the cathode of the diode D34, the same-direction input terminal (+) of the operational amplifier U9A, the negative terminal of the operational amplifier U9A, the first end of the resistor R85 and the first end of the capacitor C28 and is grounded, the second end of the resistor R65 is electrically connected to the first end of the variable resistor RP6 and the reverse input terminal (-) of the operational amplifier U9A, the positive terminal of the operational amplifier U9A is connected to the external power supply of 12V and is electrically connected to the first end of the capacitor C25, and the second end of the capacitor C25 is grounded,

[0074] The second end of the variable resistor RP6 is electrically connected to the first end of the resistor R59 and the output end of the operational amplifier U9A. The second end of the resistor R59 is electrically connected to the second end of the resistor R85, the second end of the capacitor C28 and the micro control unit.

[0075] The current amplifying unit includes a resistor R15, a resistor R17, a diode D6, a diode D7, a capacitor C3, a resistor R18, an operational amplifier U9B, a resistor R21, a capacitor C5, a resistor R22, a capacitor C6 and a resistor R2; a first end of the resistor R15 is grounded, a second end of the resistor R15 is electrically connected to the diode D6, the diode D7, a first end of the capacitor C3, a reverse input end (-) of the operational amplifier U9B and a first end of the resistor R18,

[0076] The first end of the resistor R17 is electrically connected to the secondary overcurrent and current detection circuit, the second end of the resistor R17 is electrically connected to the anode of the diode D6, the cathode of the diode D7, the second end of the capacitor C3 and the same-direction input terminal (+) of the operational amplifier U9B, the output end of the operational amplifier U9B is electrically connected to the second end of the resistor R18 and the first end of the resistor R21, the second end of the resistor R21 is electrically connected to the first end of the capacitor C5 and the first end of the resistor R22, the second end of the capacitor C5 is grounded, the second end of the resistor R22 is electrically connected to the first end of the capacitor C6, the first end of the resistor R25 and the micro control unit, and the second end of the resistor R25 is electrically connected to the second end of the capacitor C6 and the second end of the capacitor C5.

[0077] In this way, the voltage signal VS is reversely amplified by resistor R64, resistor R65, and operational amplifier U9A, and the negative voltage is amplified 5-7 times to become a 0-3.5V voltage signal that is transmitted to the micro control unit; the current signal is amplified by resistor R15, resistor R17, and operational amplifier U9B to become a 0-3V voltage signal that is transmitted to the micro control unit.

[0078] In a preferred embodiment, the secondary side overcurrent and current detection circuit includes a current transformer LT2, a capacitor C10, a three-terminal regulator U23, a capacitor C33, a resistor R33, a resistor R31, a thyristor SR1, a resistor R32, a resistor R79, a diode D13, a diode D15, a diode D12, a diode D14, and a resistor R72;

[0079] The positive electrode of the capacitor C10 is connected to the external power supply 12 and is electrically connected to the pin IN of the three-terminal regulator U23. The negative electrode of the capacitor C10 is electrically connected to the GND pin of the three-terminal regulator U23 and is grounded. The OUT pin of the three-terminal regulator U23 is electrically connected to the external power supply of 5V, the resistor R33 and the positive electrode of the capacitor C33. The negative electrode of the capacitor C33 is electrically connected to the GND pin of the three-terminal regulator U23.

[0080] The resistor R33 is electrically connected to the resistor R31 and the anode of the thyristor SR1. The resistor R31 is electrically connected to the external power supply VCC-I. The cathode of the thyristor SR1 is electrically connected to the first end of the resistor R29, the first end of the capacitor C8, the first end of the resistor R79, the anode of the diode D15 and the anode of the diode D14. The control electrode of the thyristor SR1 is electrically connected to the second end of the resistor R29, the second end of the capacitor C8 and the first end of the resistor R32.

[0081] The second end of the resistor R32 is electrically connected to the second end of the resistor R79, the cathode of the diode D13 and the cathode of the diode D12, the cathode of the diode D15 is electrically connected to the anode of the diode D13, the first end of the resistor R72 and one end of the coil two of the current transformer LT2, the cathode of the diode D14 is electrically connected to the anode of the diode D12, the resistor R72 and the other end of the coil two of the current transformer LT2, one end of the coil one of the current transformer LT2 is electrically connected to the DC-end of the winding N2 of the transformer T3, the other end of the coil one of the current transformer LT2 is electrically connected to the micro control unit and the resistor R30, the resistor R30 is electrically connected to the resistor R17 and the resistor R30A of the secondary current and voltage amplifier circuit, and the resistor R30A is grounded.

[0082] Among them, when the secondary current detection circuit outputs overcurrent or momentary short circuit, the transformer LT2 senses a peak pulse signal, which is rectified by diodes D12, D13, D14, and D15 to output a high level, triggering the thyristor SR1 to make the power supply end of the isolation drive conductive to the ground, pulling down the primary power supply of the optoelectronic isolation chip U3, and shutting off the drive signal.

[0083] When the microcontroller unit outputs PWM waves 1 and PWM2 (two PWM waves with a maximum frequency of 40KHz and a minimum duty cycle of 1%) to the isolation drive circuit, the half-bridge conversion circuit is turned on, and the DC square wave of about 300V is boosted through the isolation transformer T3. The phase difference between the PWM1 signal and the PWM2 signal is 180 degrees. The duty cycle is gradually increased, and the single-sided modulation is adjusted to 49.5%. The voltage is detected and compared with the set voltage. If the voltage is not enough (not reaching the set value), the frequency is reduced in steps of 500Hz until the detection voltage reaches the set voltage. The minimum frequency is limited to 16K Hz. The secondary side overcurrent and current detection circuit detects in real time. When the detection voltage is higher than the set voltage, the frequency is increased to achieve automatic voltage stabilization.

[0084] The present invention is not limited to what is described in the specification and implementation modes, and therefore, additional advantages and modifications can be easily realized by those familiar with the art. Therefore, without departing from the spirit and scope of the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details, representative devices, and illustrative examples shown and described herein.

Claims

1. A soft-switching high-voltage power supply system with adjustable output, characterized in that: include: Half-bridge conversion circuit, transformer T3, output rectification and filtering circuit, secondary side overcurrent and current detection circuit, isolation drive circuit, micro control unit, secondary side current and voltage amplification circuit, overcurrent protection circuit and primary side current sampling circuit; The half-bridge conversion circuit is connected to the mains and is electrically connected to the transformer T3 and the primary current sampling circuit. The transformer T3 is electrically connected to the output rectifier and filter circuit. The output rectifier and filter circuit is electrically connected to the secondary overcurrent and current detection circuit and the secondary current and voltage amplification circuit. The secondary overcurrent and current detection circuit is electrically connected to the isolation drive circuit and the micro control unit. The secondary current and voltage amplification circuit is electrically connected to the micro control unit. The isolation drive circuit is electrically connected to the half-bridge conversion circuit and the micro control unit.

2. The output adjustable soft-switching high voltage power supply system according to claim 1, characterized in that: The half-bridge conversion circuit includes a capacitor C101, a diode D22, a resistor R38, a resistor R40, a resistor R155, a MOS tube M1, a MOS tube M2, a resistor R108, a resistor R52, a resistor R47, a diode D27, a capacitor C45, a capacitor C47 and a capacitor C48; The positive electrode of the capacitor C101, the drain of the MOS tube M1 and the capacitor C45 are electrically connected to the mains, the gate of the MOS tube M1 is electrically connected to the resistor R155, the resistor R38 and the resistor R40, the resistor R40 is electrically connected to the anode of the diode D22, the cathode of the diode D22 is electrically connected to the resistor R38 and the isolation drive circuit, and the resistor R155 is also electrically connected to the isolation drive circuit. The source of the MOS tube M1 is electrically connected to the resistor R155 and the drain of the MOS tube M2, the gate of the MOS tube M2 is electrically connected to the resistors R108, R52 and R47, the resistor R108 is electrically connected to the source of the MOS tube M2, the negative electrode of the capacitor C101 and the capacitor C47, the negative electrode of the capacitor C101 is grounded, the resistor R52 is electrically connected to the anode of the diode D27, the cathode of the diode D27 is electrically connected to the resistor R47 and the isolation drive circuit, the capacitor C45 is electrically connected to the capacitor C48 and the capacitor C47, the capacitor C48 is electrically connected to the T-1 end of the winding N1 of the transformer T3, and the source of the MOS tube M1 is electrically connected to the current transformer LT1 of the primary current sampling circuit.

3. The output adjustable soft switching high voltage power supply system according to claim 2, characterized in that: The output rectifier and filter circuit includes capacitor C18, capacitor C17, capacitor C14, diode D7m, capacitor C15, capacitor C19, capacitor C20, diode D5m, capacitor C13, capacitor C8, capacitor C7, diode D6m, capacitor C21, capacitor C22, capacitor C16, capacitor C26, diode D4m, resistor R1, resistor R2, resistor R3, inductor L1, inductor L2 and inductor L3; The first end of the capacitor C18, the first end of the capacitor C17, and the first end of the capacitor C14 are electrically connected to the ZL end of the winding N2 of the transformer T3, the second end of the capacitor C18, the second end of the capacitor C17, and the second end of the capacitor C14 are electrically connected to the anode of the diode D7m, the cathode of the diode D7m, the first end of the capacitor C15, the first end of the capacitor C19, and the first end of the capacitor C20 are electrically connected to the DC-end of the winding N2 of the transformer T3, the second end of the capacitor C15, the second end of the capacitor C19, and the second end of the capacitor C20 are electrically connected to the anode of the diode D5m, The cathode of the diode D5m is electrically connected to the anode of the diode D7m, the first end of the capacitor C13, the first end of the capacitor C8, the first end of the capacitor C7, and the anode of the diode D6m; the cathode of the diode D6m is electrically connected to the anode of the diode D5m, the first end of the capacitor C21, and the first end of the capacitor C22; the second end of the capacitor C21 is electrically connected to the first end of the capacitor C16 and the first end of the capacitor C26; the second end of the capacitor C22 is electrically connected to the second end of the capacitor C16 and the second end of the capacitor C26; the second ends of the capacitor C16 and the capacitor C26 are electrically connected to the anode of the diode D4m; the cathode of the diode D4m is electrically connected to the anode of the diode D6m; The first end of the resistor R1, the first end of the resistor R2, and the first end of the resistor R3 are electrically connected to the anode of the diode D4m, the second end of the resistor R1, the second end of the resistor R2, and the second end of the resistor R3 are electrically connected to the first end of the inductor L1, the first end of the inductor L2, and the first end of the inductor L3, respectively, and the second end of the inductor L1, the second end of the inductor L2, and the second end of the inductor L3 are electrically connected to each other.

4. The output adjustable soft-switching high voltage power supply system according to claim 3, characterized in that: The isolation driving circuit includes an isolation driving chip U3, a resistor R1, a resistor R2, a resistor R4, a resistor R5, a capacitor C1, a resistor R6, a resistor R3, a diode D17, a capacitor C14, a capacitor C13 and a capacitor C32; The VIA pin of the isolation driver chip U3 is electrically connected to the resistor R1, the resistor R1 is electrically connected to the resistor R4 and the DV1 end of the micro control unit, the resistor R4 is grounded, the VIB pin of the isolation driver chip U3 is electrically connected to the resistor R2, the resistor R2 is electrically connected to the resistor R5 and the DV2 end of the micro control unit, the resistor R5 is grounded, the VDDI pin of the isolation driver chip U3 is electrically connected to the capacitor C1 and the external power supply VCC-I, the capacitor C1 is grounded and electrically connected to the NC pin of the isolation driver chip U3 and the GNDI pin of the isolation driver chip U3, the DIS pin of the isolation driver chip U3 is electrically connected to the resistor R6 and the overcurrent protection circuit, the DT pin of the isolation driver chip U3 is electrically connected to the resistor R3, the resistor R6 is electrically connected to the resistor R3 and grounded, The VDDA pin of the isolation driver chip U3 is electrically connected to the first end of the capacitor C14, the first end of the capacitor C13 and the external power supply VDD, the second end of the capacitor C14, the second end of the capacitor C13 are electrically connected to the VDDBI pin of the isolation driver chip U3 and the resistor R155, the VOA pin of the isolation driver chip U3 is electrically connected to the cathode of the diode D22, the VDDB pin of the isolation driver chip U3 is electrically connected to the anode of the diode D17 and connected to the external power supply VDD, the cathode of the diode D17 is electrically connected to the VDDA pin of the isolation driver chip U3, the pin VOB of the isolation driver chip U3 is electrically connected to the resistor R47, the GNDB pin of the isolation driver chip U3 is electrically connected to the capacitor C32, and the capacitor C32 is electrically connected to the external power supply VDD.

5. The output adjustable soft-switching high voltage power supply system according to claim 4, characterized in that: The primary current sampling circuit includes a current transformer LT1, a resistor R84, a diode D11, a diode D4, a diode D5, a diode D8, a resistor R73 and a capacitor C26; the T-2 end of the coil 1 of the current transformer LT1 is electrically connected to the T-2 end of the winding N1 of the transformer T3, the HB end of the current transformer LT1 is electrically connected to the resistor R155, the first end of the coil 2 of the current transformer LT1 is electrically connected to the first end of the resistor R84, the cathode of the diode D11 and the anode of the diode D4, the second end of the coil 2 of the current transformer LT1 is electrically connected to the second end of the resistor R84, the cathode of the diode D5 and the anode of the diode D8, the cathode of the diode D4 and the cathode of the diode D8 are electrically connected to the first end of the resistor R73 and the first end of the capacitor C26, the second end of the resistor R73 and the second end of the capacitor C26 are electrically connected to the anode of the diode D11 and the anode of the diode D5.

6. The output adjustable soft-switching high-voltage power supply system according to claim 5, characterized in that: The overcurrent protection circuit includes a resistor R23, a resistor R58, a resistor R36, a resistor R16, a capacitor C41, a comparator U7A, a capacitor C17, a resistor R19, a resistor R77, a capacitor C20, a resistor R54, a resistor R53, a resistor R56, a resistor R51, a capacitor C21, a comparator U7B and a capacitor C23; The first end of the resistor R23 is electrically connected to the resistor R73 of the primary current sampling circuit, the first end of the resistor R58, the first end of the capacitor C41 and the same-direction input end of the comparator U7A are electrically connected to the second end of the resistor R23, the resistor R36 is externally connected to a 5V power supply, the second end of the resistor R36 is electrically connected to the first end of the resistor R16 and the reverse input end of the comparator U7A, the second end of the resistor R58, the second end of the resistor R16 and the second end of the capacitor C41 are electrically connected, The positive electrode of the comparator U7A is electrically connected to a 5V external power supply and to a first end of a capacitor C17, the second end of the capacitor C17 is grounded, the negative electrode of the comparator U7A is grounded, the output end of the comparator is electrically connected to a first end of a resistor R19 and a DIS pin of an isolation driver chip, the second end of the resistor R19 is electrically connected to a first end of the capacitor C17 and a first end of a resistor R77, the second end of the resistor R77 is electrically connected to an output end of the comparator U7B, a micro control unit, and a first end of a capacitor C23, The second end of the capacitor C23 is electrically connected to the same-direction input end of the comparator U7B, the first end of the capacitor C21, the first end of the resistor R51, and the first end of the resistor R56. The second end of the capacitor C21 is electrically connected to the second end of the resistor R56 and is grounded. The second end of the resistor R51 is electrically connected to the resistor R73. The reverse input end of the comparator U7B is electrically connected to the first end of the resistor R53. The second end of the resistor R53 is electrically connected to the first end of the resistor R54, the first end of the capacitor C20, and the micro control unit. The second end of the resistor R54 is electrically connected to the second end of the capacitor C20 and is grounded.

7. The output adjustable soft-switching high-voltage power supply system according to claim 6, characterized in that: The secondary current and voltage amplification circuit includes a voltage amplification unit and a current amplification unit, wherein the voltage amplification unit includes a resistor R81, a capacitor C37, a capacitor C27, a diode D33, a diode D34, a resistor R65, a variable resistor RP6, a resistor R60, an operational amplifier U9A, a capacitor C25, a resistor R59, a resistor R85 and a capacitor C28; The first end of the resistor R81 is electrically connected to the resistor R155 of the half-bridge conversion circuit, the first end of the capacitor C37 and the first end of the resistor R64, the second end of the resistor R81 is electrically connected to the second end of the capacitor C37 and is grounded, the second end of the resistor R64 is electrically connected to the first end of the capacitor C27, the cathode of the diode D33, the anode of the diode D34 and the first end of the resistor R65, the second end of the capacitor C27 is electrically connected to the second end of the capacitor C37, the anode of the diode D33, the cathode of the diode D34, the same-direction input end of the operational amplifier U9A, the negative terminal of the operational amplifier U9A, the first end of the resistor R85 and the first end of the capacitor C28 and is grounded, the second end of the resistor R65 is electrically connected to the first end of the variable resistor RP6 and the reverse input end of the operational amplifier U9A, the positive terminal of the operational amplifier U9A is connected to the external power supply of 12V and is electrically connected to the first end of the capacitor C25, and the second end of the capacitor C25 is grounded, The second end of the variable resistor RP6 is electrically connected to the first end of the resistor R59 and the output end of the operational amplifier U9A. The second end of the resistor R59 is electrically connected to the second end of the resistor R85, the second end of the capacitor C28 and the micro control unit.

8. The output adjustable soft-switching high-voltage power supply system according to claim 7, characterized in that: The current amplifying unit includes a resistor R15, a resistor R17, a diode D6, a diode D7, a capacitor C3, a resistor R18, an operational amplifier U9B, a resistor R21, a capacitor C5, a resistor R22, a capacitor C6 and a resistor R2; a first end of the resistor R15 is grounded, a second end of the resistor R15 is electrically connected to the diode D6, the diode D7, a first end of the capacitor C3, a reverse input end (-) of the operational amplifier U9B and a first end of the resistor R18, The first end of the resistor R17 is electrically connected to the secondary overcurrent and current detection circuit, the second end of the resistor R17 is electrically connected to the anode of the diode D6, the cathode of the diode D7, the second end of the capacitor C3 and the same-direction input terminal (+) of the operational amplifier U9B, the output end of the operational amplifier U9B is electrically connected to the second end of the resistor R18 and the first end of the resistor R21, the second end of the resistor R21 is electrically connected to the first end of the capacitor C5 and the first end of the resistor R22, the second end of the capacitor C5 is grounded, the second end of the resistor R22 is electrically connected to the first end of the capacitor C6, the first end of the resistor R25 and the micro control unit, and the second end of the resistor R25 is electrically connected to the second end of the capacitor C6 and the second end of the capacitor C5.

9. The output adjustable soft-switching high-voltage power supply system according to claim 8, characterized in that: The secondary side overcurrent and current detection circuit includes a current transformer LT2, a capacitor C10, a three-terminal voltage regulator U23, a capacitor C33, a resistor R33, a resistor R31, a thyristor SR1, a resistor R32, a resistor R79, a diode D13, a diode D15, a diode D12, a diode D14, and a resistor R72; The positive electrode of the capacitor C10 is connected to the external power supply 12 and is electrically connected to the pin IN of the three-terminal regulator U23. The negative electrode of the capacitor C10 is electrically connected to the GND pin of the three-terminal regulator U23 and is grounded. The OUT pin of the three-terminal regulator U23 is electrically connected to the external power supply of 5V, the resistor R33 and the positive electrode of the capacitor C33. The negative electrode of the capacitor C33 is electrically connected to the GND pin of the three-terminal regulator U23. The resistor R33 is electrically connected to the resistor R31 and the anode of the thyristor SR1. The resistor R31 is electrically connected to the external power supply VCC-I. The cathode of the thyristor SR1 is electrically connected to the first end of the resistor R29, the first end of the capacitor C8, the first end of the resistor R79, the anode of the diode D15 and the anode of the diode D14. The control electrode of the thyristor SR1 is electrically connected to the second end of the resistor R29, the second end of the capacitor C8 and the first end of the resistor R32. The second end of the resistor R32 is electrically connected to the second end of the resistor R79, the cathode of the diode D13 and the cathode of the diode D12, the cathode of the diode D15 is electrically connected to the anode of the diode D13, the first end of the resistor R72 and one end of the coil two of the current transformer LT2, the cathode of the diode D14 is electrically connected to the anode of the diode D12, the resistor R72 and the other end of the coil two of the current transformer LT2, one end of the coil one of the current transformer LT2 is electrically connected to the DC-end of the winding N2 of the transformer T3, the other end of the coil one of the current transformer LT2 is electrically connected to the micro control unit and the resistor R30, the resistor R30 is electrically connected to the resistor R17 and the resistor R30A of the secondary current and voltage amplifier circuit, and the resistor R30A is grounded.

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