A topology and method for continuous adjustable 0V~30KV DC output suitable for ultra-high stability

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By combining a boost output module, a voltage doubler rectifier module, an output voltage closed-loop feedback module, and a voltage feedforward circuit, a continuously adjustable DC high voltage output with ultra-high stability and extremely low ripple from 0V to 30KV is achieved. This solves the problems of narrow voltage regulation range and insufficient stability in existing technologies and is suitable for high-precision industries.

CN122437395APending Publication Date: 2026-07-21TIANJIN HUIGAO MAGNETICS +1

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Patent Information

Authority / Receiving Office: CN · China
Patent Type: Applications(China)
Current Assignee / Owner: TIANJIN HUIGAO MAGNETICS
Filing Date: 2026-05-18
Publication Date: 2026-07-21

AI Technical Summary

Technical Problem

Existing high-voltage power supply topologies cannot simultaneously achieve continuous adjustability from 0V to 30KV and ultra-high stability, and have large output ripple, which cannot meet the stringent requirements of high-precision industries.

Method used

The system employs a combination design of a boost output module, a voltage doubler rectifier module, an output voltage closed-loop feedback module, a PWM closed-loop control module, and a voltage feedforward circuit module. Through high-frequency boost, multi-stage voltage doubler rectification, and dual-loop control, it achieves continuously adjustable DC output from 0V to 30KV, and reduces ripple through an RC filter network.

Benefits of technology

It achieves a continuously adjustable DC high voltage output of 0V~30KV, with ultra-high stability and extremely low ripple, meeting the needs of high-precision instruments such as electron microscopes and mass spectrometers. It has a fast dynamic response speed, strong adaptability, and is easy to expand.

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Abstract

The application discloses a kind of continuous adjustable 0V~30kV DC output topology structure and method suitable for ultrahigh stability, belong to high voltage power supply technical field, including boost output module, voltage doubler rectifier output module, output voltage closed-loop feedback module, PWM closed-loop control module and voltage feedforward circuit module.External DC voltage is converted into high-frequency AC high voltage by boost output module after being regulated by voltage feedforward and PWM closed-loop control, and then converted into DC high voltage by multi-stage voltage doubler rectification, two-stage RC filter network is connected in series in output path to reduce ripple.Output voltage closed-loop feedback module precisely samples high voltage output, and feeds back to PWM closed-loop control module;Voltage feedforward circuit module directly samples input voltage change and feeds forward to control loop, forming double-loop regulation mechanism.The application realizes 0V~30kV wide-range continuous adjustable, ultrahigh stability, ultralow ripple DC high voltage output, and can meet the stringent requirements of high-precision instruments such as electron microscope and mass spectrometer on high voltage power supply.

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Description

Technical Field

[0001] This invention relates to the field of high-voltage power supply technology, specifically to a continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30KV. Background Technology

[0002] With the continuous development of electronic technology, high-voltage and ultra-high-voltage topologies are widely used in high-precision industries (such as electron microscopes and mass spectrometers). Currently, the most common high-voltage outputs in the industry are fixed voltage levels or power supplies with narrow adjustment ranges, such as 5KV, 10KV, 15kV, and 20KV.

[0003] However, in these applications with extremely demanding environmental requirements, not only is a wide voltage output range (0V~30KV continuously adjustable) required, but also extremely high circuit stability and ultra-low output ripple. Existing conventional adjustable power supply topologies often cannot simultaneously meet such a wide voltage regulation range and high stability requirements. Therefore, a new circuit topology is urgently needed to solve these problems. Summary of the Invention

[0004] The purpose of this invention is to provide a continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30KV. This structure effectively solves the problems of narrow voltage regulation range and large output ripple in the prior art through a unique boost output, voltage doubler rectification and multi-loop control design, and realizes wide-range and high-precision high-voltage DC output.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV, comprising: The boost output module is used to boost the input DC voltage into a high-frequency AC high voltage. A voltage multiplier rectifier output module is electrically connected to the boost output module and is used to convert the high-frequency AC high voltage into DC high voltage through multi-stage voltage multiplier rectification. The output voltage closed-loop feedback module is electrically connected to the output terminal of the voltage doubler rectifier output module, and is used to sample the DC high voltage and generate a feedback signal; A PWM closed-loop control module, electrically connected to both the output voltage closed-loop feedback module and the boost output module, is used to adjust the input voltage of the boost output module according to the feedback signal; and The voltage feedforward circuit module is electrically connected to the PWM closed-loop control module and is used to sample the input voltage change and feed it forward to the PWM closed-loop control module.

[0006] Furthermore, the boost output module includes: Transformer T1 has its primary winding terminal 5 connected to power supply VC2, and its secondary winding outputs high-frequency AC high voltage. The power MOSFET TR1 has its drain connected to the same terminal 2 of the primary winding, its source connected to reference ground GND, and its gate connected to pin 11 of the PWM controller chip U1 via resistor R80. The PWM controller chip U1 has its pin 15 connected to power supply VC1 via resistor R19, pin 13 connected to power supply VC1 via Zener diode Q2, pin 16 connected to pin 1 via resistor R18, pin 16 connected to reference ground via resistor R84 and adjustable resistor RV2, and pin 9 electrically connected between resistor R84 and resistor RV2.

[0007] Furthermore, the PWM controller chip U1 is model SG3525AP013TR.

[0008] Furthermore, a Zener diode Q1 is connected between the gate and source of the power MOSFET TR1, with the anode of the Zener diode Q1 connected to the source.

[0009] Furthermore, the voltage multiplier rectifier output module is composed of six cascaded voltage multiplier units. Each voltage multiplier unit includes a charging capacitor and a rectifier diode. Its input terminal is connected to the opposite-name terminal TP1 of the secondary winding of transformer T1 in the boost output module, and its output terminal forms a high-voltage output terminal TP6 after passing through two-stage RC filter networks.

[0010] Furthermore, the output voltage closed-loop feedback module includes: resistors R81, R86, R57, and R56 connected in series between the high-voltage output terminal TP6 and the reference ground; an operational amplifier U7A, whose inverting input pin 2 is connected to the node between resistors R57 and R56, its non-inverting input pin 3 is connected to the reference ground via resistor R56, and its output pin 1 is connected to the closed-loop feedback terminal FB of the PWM closed-loop control module.

[0011] Furthermore, the PWM closed-loop control module includes: a power transistor TR2, whose collector is connected to the input power supply VC1, and whose emitter outputs a dynamically adjusted voltage VC2 to the boost output module; transistors U9 and Q8, used to drive the base of the power transistor TR2; and a common cathode switching diode Q9, whose middle node is connected to the closed-loop feedback terminal FB of the output voltage closed-loop feedback module.

[0012] Furthermore, the voltage feedforward circuit module includes: resistor R22, capacitor C16, resistor R26, and capacitor C30, which are connected in series between voltage VC2 and test point TP8; diodes D6 and D5, which are connected between test point TP8 and reference ground; and capacitor C62, resistor R83, resistor R51, capacitor C18, resistor R27, and capacitor C17, which are used to couple the feedforward signal to the closed-loop feedback terminal FB.

[0013] This invention also provides a high-voltage DC output method based on the aforementioned continuously adjustable 0V~30kV DC output topology suitable for ultra-high stability, comprising the following steps: The input DC voltage is regulated by voltage feedforward and PWM closed-loop control and then input to the boost output module; The voltage is boosted to high-frequency AC high voltage through a high-frequency step-up transformer; The high-frequency AC high voltage is converted into DC high voltage through a multi-stage voltage multiplier rectifier circuit; High-frequency ripple is filtered out by an RC filter network in the DC high-voltage output path; The output high voltage is sampled by a resistor divider to generate a feedback signal; The feedback signal and the feedforward signal are input together into the PWM closed-loop control module to dynamically adjust the input voltage of the boost output module, so as to achieve a continuously adjustable and ultra-high stability DC high voltage output from 0V to 30kV.

[0014] Compared with the prior art, the present invention has the following beneficial effects: Wide and continuously adjustable output voltage range: This invention uses a topology that combines high-frequency boost in the front stage with multi-stage voltage multiplier rectification in the back stage, along with PWM closed-loop control, to achieve a wide range of DC high voltage output from 0V to 30kV. The voltage regulation is continuous and stepless, overcoming the shortcomings of traditional high voltage power supplies that can only output fixed levels or have a narrow adjustment range.

[0015] Extremely high output stability: This invention employs a dual-loop control mechanism that coordinates the output voltage closed-loop feedback module and the voltage feedforward circuit module. The feedback loop precisely samples the output high voltage and compares it with a reference voltage, dynamically adjusting the operating state of the power transistor to form deep negative feedback; the feedforward loop directly samples input voltage fluctuations, compensating for their impact on the output in advance. The combination of these two significantly improves the static stability and dynamic response speed of the power supply system, enabling the output voltage to maintain ultra-high stability even under load changes or input fluctuations.

[0016] Extremely low output ripple: This invention incorporates a two-stage RC filter network in series in the high-voltage output path of the voltage doubler rectifier output module, which can effectively filter out the high-frequency switching ripple and spike noise generated during the voltage doubler rectification process, ensuring that the final output DC high voltage has extremely low ripple characteristics, meeting the stringent power quality requirements of high-precision instruments such as electron microscopes and mass spectrometers.

[0017] Fast dynamic response: The voltage feedforward circuit module directly samples the changes in the input voltage VC1 and quickly couples it to the PWM control loop. It can adjust the operating state of the power transistor without waiting for the output feedback delay, thereby achieving rapid compensation when the input voltage fluctuates, which greatly improves the transient response performance of the power supply system.

[0018] Highly adaptable and easily expandable: By adjusting the number of stages of the voltage doubler rectifier module or changing the output amplitude of the preceding boost module, the output specifications can be flexibly configured over a wider voltage range, exhibiting excellent scalability and platform design potential. Attached Figure Description

[0019] Figure 1 This is a system flowchart of the topology of the present invention; Figure 2 This is a circuit schematic diagram of the boost output module of the present invention; Figure 3 This is a circuit diagram of the voltage doubler rectifier output module and the output voltage closed-loop feedback module of the present invention; Figure 4 This is a circuit diagram of the PWM closed-loop control module and the voltage feedforward adjustment module of the present invention. Detailed Implementation

[0020] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the invention.

[0021] like Figure 1 As shown, the topology of this invention mainly consists of five parts: a boost output module, a voltage doubler rectifier output module, an output voltage closed-loop feedback module, a voltage feedforward regulation module, and a PWM closed-loop control module.

[0022] The following will be discussed separately. Figures 2 to 4 The circuit modules shown are described in detail, including their structure and connections.

[0023] like Figure 2 As shown, this module constitutes the first-stage boost unit of the circuit, used to boost the input DC voltage (e.g., 24V) to a high-frequency AC high voltage (e.g., 2.5kV). PWM boosting is completed through the transformer's turns ratio. This module completes the first-stage boost, providing the foundation for the subsequent voltage multiplier rectification. Its specific circuit connection structure is as follows: The core components include: transformer T1, power MOSFET TR1, PWM controller chip U1, and rectifier filter unit; among which, The non-signature terminal (terminal 5) of the primary winding of transformer T1 is connected to the power supply (electric node) VC2, and the same-signature terminal (terminal 2) is connected to the drain of power MOSFET TR1; the source of power MOSFET TR1 is connected to reference ground GND, and the gate of power MOSFET TR1 is connected to pin 11 of PWM controller chip U1 via resistor R80; Pin 13 of the PWM controller chip U1 is connected to the power supply (electric node) VC1 via the isolation Zener diode Q2; preferably, a capacitor C10 is also connected between pin 13 and the reference ground GND; Pin 15 of the PWM controller chip U1 is connected to the power supply (electric node) VC1 via resistor R19; preferably, a capacitor C12 is also connected between pin 15 and the reference ground GND. A resistor R18 is connected between pin 16 and pin 1 of the PWM controller chip U1; a resistor R84 and a resistor RV2 are also connected in series between pin 16 and the reference ground GND, and pin 9 is electrically connected to resistors R84 and RV2; preferably, resistor RV2 is an adjustable resistor. Preferably, a capacitor C11 is also connected between pin 16 and the reference ground. Preferably, a capacitor C13 is also connected between pin 9 and the reference ground GND.

[0024] After pins 5 and 7 of the PWM controller chip U1 are connected, they are connected to the reference ground GND via capacitor C9.

[0025] Pin 2 of the PWM controller chip U1 is connected to reference ground GND via resistor R17.

[0026] A resistor R16 and a resistor RV1 are connected in series between pin 6 of the PWM controller chip U1 and the reference ground GND. Preferably, resistor RV1 is an adjustable resistor.

[0027] After connecting pins 12 and 10 of the PWM controller chip U1, connect them to the reference ground GND.

[0028] Preferably, the PWM controller chip U1 is model SG3525AP013TR.

[0029] Preferably, a resistor R79 and a capacitor C32 are connected in series between the drain and source of the power MOSFET TR1.

[0030] Preferably, a Zener diode Q1 is connected between the gate and source of the power MOSFET TR1, i.e., the gate is connected to the negative terminal of the Zener diode Q1, and the positive terminal of the Zener diode Q1 is connected to the source. Alternatively, a Zener diode Q1 is connected between the gate of the power MOSFET TR1 and the reference ground GND, i.e., the gate is connected to the negative terminal of the Zener diode Q1, and the positive terminal of the Zener diode is connected to the reference ground GND.

[0031] Preferably, a capacitor C14 and an electrolytic capacitor C1 are connected between the power supply VC2 and the reference ground GND, respectively.

[0032] The opposite-named terminal of the secondary winding of transformer T1 is connected to test point TP1, and the same-named terminal (0 terminal) of the secondary winding of transformer T1 is connected to the power supply (electric node) VC3. A capacitor C22, a resistor R66, and a resistor R67 are connected in parallel between the same-name terminal (0 terminal) of the secondary winding of transformer T1 and the reference ground GND. Zener diodes Q4 and Q3 are connected in series between the same-name terminal (0 terminal) of the secondary winding of transformer T1 and the reference ground GND. The positive terminals of the two Zener diodes are connected together, and the negative terminals are connected to the same-name terminal (0 terminal) and the reference ground GND respectively.

[0033] like Figure 3 As shown, this circuit includes a voltage doubler rectifier output module and an output voltage closed-loop feedback module.

[0034] The core of the voltage multiplier rectifier output module is a voltage multiplier rectifier network composed of multiple high-voltage capacitors and high-voltage diodes. This network consists of six cascaded voltage multiplier units, each of which includes a charging capacitor and a rectifier diode, forming a multi-stage voltage multiplier rectification of the preceding AC high voltage.

[0035] Specifically, test point TP1 receives from Figure 2 The boost output module uses a high-frequency AC high voltage on the secondary side of transformer T1. This AC signal is fed into a rectifier and voltage multiplier unit consisting of a first-stage capacitor and a first-stage diode. In each stage, the unidirectional conductivity of the diode and the energy storage characteristics of the capacitor work together to progressively boost the AC voltage and convert it into DC voltage. After six stages of continuous voltage multiplication and rectification, the required high-voltage DC is obtained at the final output stage.

[0036] Specifically, to further improve the quality of the output DC voltage, a two-stage RC filter network is connected in series in the high-voltage output circuit. For example... Figure 3 As shown in the red box, the network consists of a resistor connected in series in the high-voltage path and a capacitor connected in parallel between the high-voltage output terminal and the reference ground (GND). This RC filter network can effectively filter out the high-frequency ripple noise generated during the voltage doubler rectification process, thereby ensuring that the final output high voltage has extremely low ripple characteristics.

[0037] Taking the final output of 15kV as an example, the voltage output of up to 15kV is achieved by boosting the voltage by 6 times. The part in red in the figure is the additional two-stage RC filter circuit. This circuit can effectively reduce the output ripple noise, so that the high voltage output ripple noise is filtered out by removing high frequency ripple noise. In practical applications, the continuously adjustable output from 0V to 30kV can be achieved by adjusting the number of boosting stages and the input of the preamplifier.

[0038] The input terminal of the first-stage voltage multiplier unit and Figure 2 The secondary winding of transformer T1, connected to the opposite-name terminal and test point TP1, is used to receive high-frequency AC high voltage. The specific connection relationship is as follows: One end of capacitor C2 is connected to test point TP1. The other end of capacitor C2 is connected to one end of capacitor C50, the anode of diode D3, and the cathode of diode D1. The cathode of diode D3 is connected to one end of capacitor C61 and power supply (electrical node) VC3. The other end of capacitor C61 is connected to the anode of diode D1, the cathode of diode D11, and one end of capacitor C59. The other end of capacitor C50 is connected to one end of capacitor C54, the anode of diode D11, and the cathode of diode D8. The anode of diode D8 is connected to the other end of capacitor C59, one end of capacitor C58, and the cathode of diode D13. The other end of capacitor C54 is connected to the anode of diode D13, the cathode of diode D9, and one end of capacitor C53. The anode of diode D9 is connected to the other end of capacitor C58 and a jumper short-circuit one end of capacitor C60. The other end of capacitor C53 is connected to the anode of diode D10. The cathode of diode D10 is connected to a jumper short-circuit the other end of capacitor C60 and one end of resistor R85. like Figure 3 As shown in the red box, the other end of resistor R85 is connected to one end of capacitor C44, one end of capacitor C43, and one end of resistor R30; the other end of capacitor C44 is connected to one end of capacitor C45, one end of capacitor C43, and one end of capacitor C27; the other end of capacitor C45 is connected to one end of capacitor C46, one end of capacitor C27, and one end of capacitor C25; the other ends of capacitor C46 and capacitor C25 are respectively connected to reference ground CND; the other end of resistor R30 is connected to one end of resistor R407, and the other end of resistor R407 is connected to the high-voltage output terminal TP6, which is used to provide a continuously adjustable DC high voltage of 0V~30kV to the load; The other end of resistor R30 is also connected to one end of resistor R81 and one end of capacitor C42. The other end of capacitor C42 is connected in series with capacitors C41 and C40 between it and the reference ground GND. The other end of resistor R81 is connected to one end of resistor R86. The other end of resistor R86 is connected to the middle node of dual diode Q10, one end of resistor R57, and one end of capacitor C48. The negative terminal of dual diode Q10 is connected to 15V, and the positive terminal of dual diode Q10 is connected to the power supply (electrical node) -VC1. The other end of capacitor C48 is connected to the reference ground GND. The other end of resistor R57 is connected to the middle node of dual diode Q20. The negative terminal of diode Q20 is connected to pin 3 of the non-inverting input of operational amplifier U7A, and the positive terminal of dual diode Q20 is connected to pin 2 of the inverting input of operational amplifier U7A. Pin 8 of the power supply terminal of operational amplifier U7A is connected to one end of capacitor C21 and one end of resistor R33. The other end of capacitor C21 is connected to reference ground GND, and the other end of resistor R33 is connected to 15V. Pin 4 of the ground terminal of operational amplifier U7A is connected to one end of capacitor C26 and one end of resistor R58. The other end of capacitor C26 is connected to reference ground GND, and the other end of resistor R58 is connected to power supply (electrical node) -VC1. The power supply (electrical node) -VC1 is -15V.

[0039] The non-inverting input pin 3 of operational amplifier U7A is also connected to one end of capacitor C49 and one end of resistor R56. The other end of capacitor C49 is connected to reference ground, the other end of resistor R56 is connected to one end of resistor R55, and the other end of resistor R55 is connected to reference ground GND. The inverting input pin 2 of operational amplifier U7A is also connected to one end of capacitor C56, one end of capacitor C57, and one end of resistor R53, respectively. The other ends of capacitor C56 and capacitor C57 are connected to the output pin 1 (closed-loop feedback FB terminal) of operational amplifier U7A. The other end of resistor R53 is connected to one end of resistor R52, and the other end of resistor R52 is connected to the output pin 1 (closed-loop feedback FB terminal) of operational amplifier U7A.

[0040] The output voltage closed-loop feedback module is used to accurately sample the final high voltage output for dynamic adjustment of the subsequent control loop. The high voltage output terminal is connected in series with resistors R81, R86, R57, and R56, with the other end of resistor R56 connected to reference ground (GND). The sampling feedback point is located at the connection node between resistors R57 and R56. Through this resistor divider network, the 0V~30KV high voltage signal is linearly attenuated proportionally into a low voltage feedback signal, which is then sent to… Figure 4 The PWM closed-loop control module shown is used for processing.

[0041] like Figure 4As shown, the power supply (electrical node) VC1 is a 24V input voltage. The closed-loop feedback of the output voltage is dynamically adjusted by this circuit to become the VC2 voltage, which is then fed into... Figure 2 The transformer boost output module in the diagram supplies power to the primary winding of transformer T1. The feedback here is a dynamic adjustment process, achieved by alternately switching on and off the power transistor TR2. The red box in the diagram represents the voltage feedforward adjustment module, which sends the voltage from VC2 into the transformer to complete the boost conversion.

[0042] The PWM closed-loop control module receives data from... Figure 3 The closed-loop feedback signal of the output voltage at the connection node between resistors R57 and R56 is amplified by an internal error amplifier and compared with a reference voltage to generate a control signal.

[0043] This control signal is used to drive the control terminal (base or gate) of the power transistor TR2. By adjusting the ratio of the on and off times or the on-state voltage drop of the power transistor TR2, the input voltage VC1 is modulated.

[0044] Specifically, the conducting terminal (such as the collector or drain) of the power transistor TR2 is connected to the input power supply VC1, while the other conducting terminal (such as the emitter or source) serves as the output terminal, generating a dynamically regulated voltage VC2. Voltage VC2 is directly fed into… Figure 2 In the boost output module shown.

[0045] The voltage feedforward circuit module directly samples the changes in the input voltage VC1. This feedforward signal is introduced into the PWM closed-loop control loop, so that when the input voltage VC1 fluctuates, the control circuit can directly adjust the operating state of the power transistor (TR2) without waiting for the feedback delay of the output high voltage, thereby quickly compensating for the changes in the input voltage and greatly improving the dynamic response speed and stability of the entire power supply system.

[0046] Specifically, the PWM closed-loop control module includes: power supply (electrical node) VC1 is connected to the emitter of transistor Q7, one end of capacitor C15, one end of resistor R20, and one end of resistor R21; the other end of capacitor C15 is connected to the base of transistor Q7, one end of resistor R87, and one end of resistor R24; the other end of resistor R87 is connected to power supply (electrical node) VC2; the other end of resistor R24 is connected to the other end of resistor R20, the other end of resistor R21, one end of resistor R23, the emitter of transistor U9, the collector of power transistor TR2, and the cathode of diode D12; the emitter of power transistor TR2 is connected to diode D12. The positive terminal of the transistor is connected to the power supply (electric node) VC2 and one end of resistor R22; the base of power transistor TR2 is connected to the collector of transistor U9 and one end of resistor R75; the base of transistor U9 is connected to the other end of resistor R23, the collector of transistor Q7 and one end of resistor R77; the other end of resistor R77 is connected to one end of resistor R78; the other end of resistor R78 is connected to the collector of transistor Q8; the emitter of transistor Q8 is connected to one end of resistor R76, one end of resistor R25 and the lower end of common cathode switching diode Q9; the other end of resistor R76 is connected to the other end of resistor R75; the other end of resistor R25 is connected to reference ground GND. The middle node of the common cathode switching diode Q9 is connected to the base of the transistor Q8, and the upper end of the common cathode switching diode Q9 is connected to one end of the resistor R29.

[0047] Specifically, the voltage feedforward circuit module includes: the other end of resistor R22 is connected to one end of capacitor C16 and one end of resistor R26 respectively, the other end of capacitor C16 is connected to reference ground GND, and the other end of resistor R26 is connected to one end of capacitor C30. The other end of capacitor C30 is connected to test point TP8, the positive terminal of diode D6, one end of capacitor C62, one end of resistor R83, one end of resistor R53, one end of capacitor C18, and one end of resistor R27; the negative terminal of diode D6 is connected to the negative terminal of diode D5, and the positive terminal of diode D5 is connected to reference ground GND; the other end of capacitor C62 is connected to reference ground GND. The other end of resistor R83 is connected to the other end of resistor R51, and then connected to the closed-loop feedback FB terminal; The other end of resistor R27 is connected to one end of capacitor C17, and the other end of capacitor C17 is connected to the other end of capacitor C18, and then connected to the other end of resistor R29.

[0048] Intermediate node connection of common cathode switching diode Q9 Figure 3 The output pin 1 of the operational amplifier U7A (i.e., the closed-loop feedback FB terminal).

[0049] Working principle The topology described in this invention achieves continuously adjustable and ultra-high stability DC high-voltage output from 0V to 30kV through a collaborative working mechanism of "pre-stage high-frequency boost, post-stage voltage multiplier rectification, and multi-loop precision control." Its specific working process is as follows: First, the external DC input voltage (e.g., 24V VC1) is regulated by the voltage feedforward circuit module and the PWM closed-loop control module to generate a dynamically controlled DC voltage VC2, which is supplied to the boost output module. In the boost output module, the PWM controller chip U1 generates a fixed-frequency pulse width modulation signal, driving the power MOSFET TR1 to operate in high-frequency switching mode, inverting the VC2 DC voltage into high-frequency pulsed AC voltage, and then boosting the voltage amplitude to the first-stage high voltage (e.g., approximately 2.5kV) through the high-frequency boost transformer T1. The high-frequency AC high voltage output from the secondary winding of transformer T1 is then fed into the subsequent circuit via test point TP1.

[0050] Secondly, the voltage doubler rectifier output module receives high-frequency AC high voltage from the secondary winding of transformer T1. This module consists of six cascaded capacitor-diode voltage doubler units. Utilizing the unidirectional conduction of diodes and the charge pump effect of capacitors, it alternately charges each stage of capacitors during the positive and negative half-cycles of the AC voltage, superimposing the voltage of the previous stage. Finally, at the negative terminal of the final diode D9 (HV_OUT node), a DC high voltage output approximately six times the peak value of the input AC voltage is obtained. By changing the output voltage amplitude of the preceding boost module or adjusting the number of voltage doubler stages, the final output voltage can be continuously adjusted within the range of 0V to 30kV. In particular, a two-stage RC filter network is connected in series in the high-voltage output path to effectively filter out the high-frequency switching ripple and spike noise generated during the voltage doubler rectification process, ensuring that the output DC high voltage has extremely low ripple characteristics and meeting the requirements of ultra-high stability applications.

[0051] Meanwhile, the output voltage closed-loop feedback module precisely samples the final output high voltage. The high voltage is proportionally attenuated into a low voltage feedback signal by a high-precision voltage divider network composed of resistors R81, R86, R57, and R56. This feedback signal is then buffered and conditioned by operational amplifier U7A before being sent to the error comparison input of the PWM closed-loop control module.

[0052] In the PWM closed-loop control module, the feedback signal is compared with an internal high-stability reference voltage. The amplified control signal, after error correction, dynamically adjusts the conduction level or duty cycle of the power transistor TR2 through the common-cathode switching diode Q9 and the driving circuits of transistors Q8 and U9. When the output voltage deviates from the set value due to load changes or other disturbances, the feedback loop automatically adjusts the operating state of TR2, changes the voltage value of VC2, and then adjusts the input energy of the primary winding of the step-up transformer T1, ultimately ensuring that the output high voltage accurately returns to the preset value, forming a deep negative feedback closed-loop control that guarantees ultra-high stability of the output voltage.

[0053] Furthermore, the voltage feedforward circuit module directly samples the fluctuations in the input voltage VC1. Once VC1 changes, the feedforward circuit immediately couples the change to the PWM control loop, adjusting the control parameters of the power transistor TR2 in advance. This quickly compensates for the impact of input voltage variations on VC2 and subsequent boost links without waiting for a lengthy feedback response delay at the output. The voltage feedforward and output voltage closed-loop feedback together form a dual-loop control mechanism, significantly improving the power system's dynamic suppression capability and transient response speed against input voltage fluctuations.

[0054] In summary, this invention achieves a wide-range voltage output through high-frequency boost and multi-stage voltage multiplier rectification, ensures low ripple characteristics through an RC filter network, and employs a dual-loop precision control strategy that combines output voltage closed-loop feedback and input voltage feedforward to ultimately obtain a continuously adjustable DC high-voltage output of 0V~30kV with ultra-high stability and ultra-low ripple. This fully meets the stringent performance requirements of high-precision instruments such as electron microscopes and mass spectrometers for high-voltage power supplies.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV, characterized in that, include: The boost output module is used to boost the input DC voltage into a high-frequency AC high voltage. A voltage multiplier rectifier output module is electrically connected to the boost output module and is used to convert the high-frequency AC high voltage into DC high voltage through multi-stage voltage multiplier rectification. The output voltage closed-loop feedback module is electrically connected to the output terminal of the voltage doubler rectifier output module, and is used to sample the DC high voltage and generate a feedback signal; The PWM closed-loop control module is electrically connected to the output voltage closed-loop feedback module and the boost output module, respectively, and is used to adjust the input voltage of the boost output module according to the feedback signal. as well as The voltage feedforward circuit module is electrically connected to the PWM closed-loop control module and is used to sample the input voltage change and feed it forward to the PWM closed-loop control module.

2. The continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV as described in claim 1, characterized in that, The boost output module includes: Transformer T1 has its primary winding terminal 5 connected to power supply VC2, and its secondary winding outputs high-frequency AC high voltage. The power MOSFET TR1 has its drain connected to the same terminal 2 of the primary winding, its source connected to reference ground GND, and its gate connected to pin 11 of the PWM controller chip U1 via resistor R80. The PWM controller chip U1 has its pin 15 connected to power supply VC1 via resistor R19, pin 13 connected to power supply VC1 via Zener diode Q2, pin 16 connected to pin 1 via resistor R18, pin 16 connected to reference ground via resistor R84 and adjustable resistor RV2, and pin 9 electrically connected between resistor R84 and resistor RV2.

3. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV as described in claim 2, characterized in that, The PWM controller chip U1 is model SG3525AP013TR.

4. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV as described in claim 2, characterized in that, A Zener diode Q1 is connected between the gate and source of the power MOSFET TR1, with the anode of the Zener diode Q1 connected to the source.

5. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV according to claim 1, characterized in that, The voltage multiplier rectifier output module is composed of six cascaded voltage multiplier units. Each voltage multiplier unit includes a charging capacitor and a rectifier diode. Its input terminal is connected to the opposite-name terminal TP1 of the secondary winding of transformer T1 in the boost output module. The output terminal is formed into a high-voltage output terminal TP6 after passing through two-stage RC filter networks.

6. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV according to claim 5, characterized in that, The output voltage closed-loop feedback module includes: resistors R81, R86, R57, and R56 connected in series between the high-voltage output terminal TP6 and the reference ground; an operational amplifier U7A, whose inverting input pin 2 is connected to the node between resistors R57 and R56, its non-inverting input pin 3 is connected to the reference ground via resistor R56, and its output pin 1 is connected to the closed-loop feedback terminal FB of the PWM closed-loop control module.

7. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV as described in claim 1, characterized in that, The PWM closed-loop control module includes: a power transistor TR2, whose collector is connected to the input power supply VC1, and whose emitter outputs a dynamically adjusted voltage VC2 to the boost output module; transistors U9 and Q8, used to drive the base of the power transistor TR2; and a common cathode switching diode Q9, whose middle node is connected to the closed-loop feedback terminal FB of the output voltage closed-loop feedback module.

8. A continuously adjustable DC output topology suitable for ultra-high stability from 0V to 30kV according to claim 1, characterized in that, The voltage feedforward circuit module includes: resistor R22, capacitor C16, resistor R26, and capacitor C30, which are connected in series between voltage VC2 and test point TP8; diodes D6 and D5, which are connected between test point TP8 and reference ground; and capacitor C62, resistor R83, resistor R51, capacitor C18, resistor R27, and capacitor C17, which are used to couple the feedforward signal to the closed-loop feedback terminal FB.

9. A high-voltage DC output method based on a continuously adjustable 0V~30kV DC output topology suitable for ultra-high stability, as described in any one of claims 1 to 8, characterized in that, Includes the following steps: The input DC voltage is regulated by voltage feedforward and PWM closed-loop control and then input to the boost output module; The voltage is boosted to high-frequency AC high voltage through a high-frequency step-up transformer; The high-frequency AC high voltage is converted into DC high voltage through a multi-stage voltage multiplier rectifier circuit; High-frequency ripple is filtered out by an RC filter network in the DC high-voltage output path; The output high voltage is sampled by a resistor divider to generate a feedback signal; The feedback signal and the feedforward signal are input together into the PWM closed-loop control module to dynamically adjust the input voltage of the boost output module, so as to achieve a continuously adjustable and ultra-high stability DC high voltage output from 0V to 30kV.