Segmented voltage regulation control method and high-voltage power supply system for realizing low-ripple high-precision output of high-voltage power supply

Abstract

The application discloses a segmented voltage regulation control method and a high-voltage power supply system for realizing low-ripple high-precision output of the high-voltage power supply, and relates to the technical field of integrated circuits.The method comprises the following steps: determining a working interval of the high-voltage power supply system according to an output voltage of the high-voltage power supply system; when the working interval of the high-voltage power supply system is a preset low-power working interval, performing closed-loop control on an input voltage of a DC-DC converter through an input voltage linear regulation loop, keeping a pulse width modulation (PWM) duty cycle of the DC-DC converter as a preset fixed value, and realizing low-ripple output of the high-voltage power supply; and when the working interval of the high-voltage power supply system is a preset high-power working interval, keeping the input voltage of the DC-DC converter as a preset constant value, and performing closed-loop control on the PWM duty cycle of the DC-DC converter through a duty cycle regulation loop, so as to adjust the output voltage of the high-voltage power supply system.

Description

Technical Field

[0001] This application relates to the field of integrated circuit technology, and in particular to a segmented voltage regulation control method and a high-voltage power supply system for achieving low-ripple and high-precision output of a high-voltage power supply. Background Technology

[0002] Low-power high-voltage power supplies are widely used in precision instruments and equipment such as electron microscopes, mass spectrometers, and photoelectric detectors. The accuracy, stability, and ripple of their output voltage directly affect the overall performance of the instrument. To adjust the output voltage of a high-voltage power supply over a wide range, current technology typically employs pulse width modulation (PWM). This involves adjusting the on-time (duty cycle) of the power switching transistor within one switching cycle to control the energy transferred from the input to the output, thereby stabilizing the output voltage.

[0003] However, relying solely on duty cycle regulation has inherent drawbacks. When a high-voltage power supply needs to output a lower voltage, the required duty cycle becomes extremely small. In this low duty cycle operating range, the controller's regulation resolution decreases significantly, control linearity deteriorates, and the system becomes exceptionally sensitive to factors such as switching delay and component parameter dispersion. These factors combined result in significant fluctuations and ripples in the final output voltage, making stability difficult to guarantee and failing to meet the low-noise, high-precision power supply requirements of precision instruments.

[0004] Therefore, existing technologies face the challenge of simultaneously achieving low ripple, high precision, and high stability at low power output in wide-range voltage regulation. Summary of the Invention

[0005] The purpose of this application is to provide a segmented voltage regulation control method and a high-voltage power supply system for achieving low-ripple and high-precision output of high-voltage power supplies, so as to solve the technical problem that existing technologies have difficulty in achieving low ripple, high precision and high stability at low power output in wide-range voltage regulation.

[0006] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a segmented voltage regulation control method for achieving low-ripple, high-precision output of a high-voltage power supply, applicable to a high-voltage power supply system including a DC-DC converter. The segmented voltage regulation control method for achieving low-ripple, high-precision output of a high-voltage power supply includes: The operating range of the high-voltage power supply system is determined based on its output voltage. When the operating range of the high-voltage power supply system is the preset low-power operating range, the input voltage of the DC-DC converter is controlled in a closed loop through the input voltage linear adjustment loop to keep the pulse width modulation (PWM) duty cycle of the DC-DC converter at a preset fixed value, thereby achieving low ripple output of the high-voltage power supply. When the operating range of the high-voltage power supply system is the preset high-power operating range, the input voltage of the DC-DC converter is kept at a preset constant value, and the pulse width modulation (PWM) duty cycle of the DC-DC converter is controlled in a closed loop through a duty cycle adjustment loop to adjust the output voltage of the high-voltage power supply system.

[0007] In one embodiment, the input voltage of the DC-DC converter is provided by a front-stage linear voltage regulation unit; Furthermore, within the low-power operating range, the input voltage of the DC-DC converter is adjusted by controlling the preceding linear voltage regulator.

[0008] In one embodiment, determining the operating range of the high-voltage power supply system based on its output voltage specifically includes: A feedback signal is acquired that is positively correlated with the output voltage of the high-voltage power supply system and related to the target voltage difference, wherein the target voltage difference is the voltage difference between the output voltage of the high-voltage power supply system and a set reference value; When the feedback signal is greater than the voltage threshold, the high-voltage power supply system is determined to be in the high-power operating range; otherwise, the high-voltage power supply system is determined to be in the low-power operating range.

[0009] In one embodiment, the duty cycle adjustment loop is implemented by a PWM control chip, and the feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is provided with a preset bias voltage, which is the voltage threshold. Specifically, when the voltage of the feedback signal rises to a level sufficient to turn on the diode and change the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range; when the voltage of the feedback signal drops to a level insufficient to turn on the diode, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

[0010] In one embodiment, the feedback signal is obtained by a second-order compensation network compensating for the target voltage difference based on the output voltage of the high-voltage power supply system.

[0011] Secondly, this application provides a high-voltage power supply system, comprising: DC-DC converter; A voltage regulation loop is used to perform closed-loop control on the input voltage of the DC-DC converter when the operating range of the high-voltage power supply system is a preset low-power operating range, so as to regulate the output voltage of the high-voltage power supply system; otherwise, the input voltage of the DC-DC converter is kept at a preset constant value. The duty cycle adjustment loop is used to perform closed-loop control of the pulse width modulation (PWM) duty cycle of the DC-DC converter when the operating range of the high-voltage power supply system is a preset high-power operating range, so as to adjust the output voltage of the high-voltage power supply system; otherwise, the PWM duty cycle of the DC-DC converter is kept at a preset fixed value.

[0012] In one embodiment, it also includes: The pre-stage linear voltage regulator unit is used to provide input voltage to the DC-DC converter and is controlled by the voltage regulation loop in the low-power operating range to regulate the input voltage of the DC-DC converter.

[0013] In one embodiment, it also includes: A feedback network is used to collect feedback signals that are positively correlated with the output voltage of the high-voltage power supply system and related to the target voltage difference, so as to determine the operating range of the high-voltage power supply system, wherein the target voltage difference is the voltage difference between the output voltage of the high-voltage power supply system and a set reference value; Specifically, when the feedback signal is greater than the voltage threshold, the high-voltage power supply system is determined to be in the high-power operating range; otherwise, the high-voltage power supply system is determined to be in the low-power operating range.

[0014] In one embodiment, the duty cycle adjustment loop is implemented by a PWM control chip, and the feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is provided with a bias network, which is used to provide a preset bias voltage, and the preset bias voltage is the voltage threshold. Specifically, when the voltage of the feedback signal rises to a level sufficient to turn on the diode and change the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range; when the voltage of the feedback signal drops to a level insufficient to turn on the diode, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

[0015] In one embodiment, the feedback network includes a comparator and a second-order compensation network connected in parallel. The comparator is used to compare the output voltage of the high-voltage power supply system with a set reference value to obtain a target voltage difference. The second-order compensation network is used to compensate the target voltage difference according to the output voltage of the high-voltage power supply system to form the feedback signal.

[0016] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides a segmented voltage regulation control method and a high-voltage power supply system for achieving low-ripple and high-precision output of a high-voltage power supply. It employs a segmented control approach combining input voltage regulation and duty cycle regulation. Within the low-power output range, the duty cycle is maintained at a preset fixed value, and closed-loop control of the output voltage is achieved through an input voltage regulation loop. When the input voltage reaches its upper limit, it remains constant, and the duty cycle regulation loop takes over output regulation, thereby achieving wide-range continuous voltage regulation of the high-voltage output. Output ripple is reduced by avoiding an excessively small duty cycle in the low-power region. In the low-power range, instead of further reducing the duty cycle for voltage reduction, output regulation is achieved by adjusting the input voltage, thus avoiding the increased output ripple caused by an excessively small duty cycle. This approach balances low ripple, high precision, and high stability during low-power output. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall architecture of a high-voltage power supply system in one embodiment of this application; Figure 2 This is a schematic diagram of segmented voltage regulation control of a high-voltage power supply in one embodiment of this application; Figure 3 This is a schematic diagram of the control of the low-power operating range in one embodiment of this application; Figure 4 This is a schematic diagram of the control of the high-power operating range in one embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the following will be combined with Figures 1-4 The present application will be further described in detail below with reference to specific implementation methods.

[0021] This application provides a segmented voltage regulation control method and a high-voltage power supply system for achieving low-ripple, high-precision output from a high-voltage power supply. It aims to solve the problems of large output ripple and low regulation accuracy caused by excessively small duty cycles in existing high-voltage power supplies at low power output. The core idea of ​​this application is to divide the entire operating range of the high-voltage power supply into a low-power operating range and a high-power operating range, and to employ different voltage regulation strategies within these two ranges. This ensures a wide range of voltage regulation capabilities while optimizing the power supply's performance under different loads.

[0022] In one specific embodiment of this application, a segmented voltage regulation control method for achieving low-ripple, high-precision output of a high-voltage power supply is applied to a high-voltage power supply system including a DC-DC converter. The segmented voltage regulation control method includes: determining the operating range of the high-voltage power supply system based on its output voltage; when the operating range of the high-voltage power supply system is a preset low-power operating range, performing closed-loop control of the input voltage of the DC-DC converter through an input voltage linear adjustment loop to maintain the pulse width modulation (PWM) duty cycle of the DC-DC converter at a preset fixed value to achieve low-ripple output of the high-voltage power supply; when the operating range of the high-voltage power supply system is a preset high-power operating range, maintaining the input voltage of the DC-DC converter at a preset constant value, and performing closed-loop control of the PWM duty cycle of the DC-DC converter through a duty cycle adjustment loop to adjust the output voltage of the high-voltage power supply system.

[0023] This method first divides the operating state of the high-voltage power supply into a preset low-power operating range and a high-power operating range based on its output voltage. When the high-voltage power supply operates in the preset low-power operating range, the core of the method lies in stabilizing one key control variable while adjusting the other. Specifically, the pulse width modulation (PWM) duty cycle of the DC-DC converter is kept at a preset fixed value, and the input voltage of the DC-DC converter is controlled in a closed-loop manner through an input voltage regulation loop. In this way, the output voltage regulation task is accomplished by the linear control of the input voltage, thereby avoiding the problem caused by the need for an extremely small duty cycle at low output and solving the linearity and stability problems of traditional PWM voltage regulation methods in this range. The above technical solution reduces output voltage ripple and improves output voltage accuracy while satisfying wide-range voltage regulation.

[0024] When the high-voltage power supply switches to a preset high-power operating range, the voltage regulation strategy changes accordingly. At this point, the method maintains the input voltage of the DC-DC converter at a preset constant value (usually its maximum available value to ensure sufficient power margin), and performs closed-loop control of the PWM duty cycle of the DC-DC converter through a duty cycle adjustment loop. Since the system operates at higher power at this time, the required duty cycle is within a relatively ideal range, resulting in high efficiency, fast response, and good linearity of PWM regulation, which can meet the voltage regulation requirements of a wide range and high power. In this way, effective regulation of the output voltage is achieved.

[0025] In one embodiment, the input voltage of the DC-DC converter is provided by a pre-stage linear regulator unit; and, in the low-power operating range, the input voltage of the DC-DC converter is regulated by controlling the linear regulator unit.

[0026] In one embodiment, determining the operating range of the high-voltage power supply system based on its output voltage specifically includes: acquiring a feedback signal that is positively correlated with the output voltage of the high-voltage power supply system and related to a target voltage difference, where the target voltage difference is the voltage difference between the output voltage of the high-voltage power supply system and a set reference value; when the feedback signal is greater than a voltage threshold, determining that the high-voltage power supply system is in a high-power operating range; otherwise, determining that the high-voltage power supply system is in a low-power operating range.

[0027] Furthermore, the duty cycle adjustment loop is implemented through a PWM control chip. The feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is set with a preset bias voltage, which is a voltage threshold. When the voltage of the feedback signal rises to a level that enables the diode to conduct and changes the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range. When the voltage of the feedback signal drops to a level that is insufficient to enable the diode to conduct, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

[0028] The feedback signal is obtained by a second-order compensation network that compensates for the target voltage difference based on the output voltage of the high-voltage power supply system. Therefore, since the feedback signal contains information about the target voltage difference, it can be used as a basis for adjustment.

[0029] The following example illustrates in detail the segmented voltage regulation control method for achieving low ripple and high-precision output of high-voltage power supply in the above specific embodiments.

[0030] In an exemplary embodiment, the segmented voltage regulation control method for achieving low-ripple, high-precision output of a high-voltage power supply includes the following steps: Step 1: Acquire the high voltage output signal (output voltage of the high voltage power supply system) and compare it with the set reference value to obtain the output error signal (voltage difference).

[0031] Step 2: The output voltage error signal is processed by feedback conditioning (implemented by a second-order compensation network) to form two feedback signals, the first of which is the duty cycle adjustment feedback signal F. BD The second channel is the input voltage regulation feedback signal FB. Vin .

[0032] Step 3: Adjust the duty cycle feedback signal F BD The diode is connected to the error input terminal of the analog control chip (PWM control chip), and a preset bias voltage composed of a bias network is set at the error input terminal.

[0033] Step 4: When the duty cycle adjustment feedback signal F BD When the corresponding voltage is not higher than the preset bias voltage and is insufficient to turn the diode forward, the duty cycle adjustment feedback signal F BD It does not participate in the error input adjustment. The potential of the error input terminal of the analog control chip is determined by the preset bias voltage. At this time, the PWM duty cycle remains at the preset fixed value.

[0034] Step 5: In the state of step 4, the input voltage regulation feedback signal FB is... Vin The output is sent to a linear voltage regulator unit to adjust the output voltage of the preceding linear voltage regulator unit, which in turn adjusts the input voltage of the subsequent DC-DC converter, thereby achieving linear regulation of the input voltage in the low-power region.

[0035] Step 6: When the output voltage of the high-voltage power supply system increases, the feedback signal also increases. When the duty cycle adjustment feedback signal F... BD When the corresponding voltage is higher than the preset bias voltage and the diode is turned on, the duty cycle adjustment feedback signal F BD It is coupled to the error input terminal of the analog control chip, changing the potential of the error input terminal.

[0036] Step 7: The analog control chip adjusts the PWM output according to the changed error input terminal potential in step 6, and the duty cycle changes from a preset fixed value to a closed-loop adjustable state, thus entering the voltage regulation process in the high-power operating range.

[0037] Step 8: In the high-power operating range, the input voltage of the front stage is kept at its maximum value or a preset constant value, and the output voltage is continuously regulated mainly by adjusting the duty cycle.

[0038] Step 9: When the output voltage of the high-voltage power supply system drops, the duty cycle adjustment feedback signal F... BDWhen the voltage drops below the preset bias voltage again and the diode is turned off, the duty cycle adjustment path ceases operation, and the high-voltage power supply system reverts to being regulated by the input voltage feedback signal FB. Vin Adjust the voltage regulation state of the LDO output in the low-power operating range.

[0039] Based on the above steps, the segmented voltage regulation control in this embodiment is achieved collaboratively by an input voltage regulation loop and a duty cycle regulation loop. The two loops share the output sampling feedback result, but perform different regulation functions in different operating ranges. Specifically, in the low-power operating range, the duty cycle remains at a preset fixed value, and the high-voltage power supply system mainly controls the preceding linear voltage regulation unit through the input voltage regulation loop to achieve output voltage regulation. In the high-power operating range, after the feedback signal for duty cycle regulation meets the conduction condition, it is introduced into the error input terminal of the control chip, and the high-voltage power supply system switches to the duty cycle regulation loop to further regulate the output voltage. The working principles of the input voltage regulation loop and the duty cycle regulation loop are explained below: 1. Input voltage regulation loop.

[0040] The input voltage regulation loop corresponds to the low-power operating range in steps 4 and 5 above. It is the main control loop in this embodiment that achieves precise adjustment of the output voltage while maintaining a preset fixed duty cycle. This loop primarily regulates the output voltage of the preceding linear voltage regulator unit, and achieves high-voltage output regulation by adjusting the input voltage of the subsequent converter.

[0041] Within this operating range, the main control object of the system is the inverter stage input voltage, and there is a relatively direct correspondence between the high-voltage output and the input voltage: V o ≈ kDV in ; in, V o This refers to the output voltage of the high-voltage power supply system. V in The input voltage of the DC-DC converter. D Duty cycle, k This is the ratio of the input voltage to the output voltage.

[0042] In the traditional method, if the input voltage V in Always maintain maximum value Then when the output voltage V o At a lower level, the required duty cycle is: ; At this time, the duty cycle D is small, the conduction time is significantly shortened, and energy is only transferred to the output terminal within a narrow time. During the rest of the time, the output capacitor mainly supplies power to the load, which can easily cause uneven charging and discharging of the output capacitor and increase the output ripple.

[0043] In this embodiment, instead of further reducing the duty cycle to regulate voltage in the low-power region, the duty cycle is kept at a preset value. D 0, the output requirements are met by linearly adjusting the input voltage, that is: ; because D Maintaining the duty cycle within a reasonable range avoids excessively low duty cycles when the output voltage is low, thus ensuring sufficient single-cycle conduction time, more uniform energy transfer on the output side, reduced output capacitor charging and discharging fluctuations, and consequently lower output ripple. Once the input voltage is adjusted to its maximum value, high power output is achieved by adjusting the duty cycle. At this point, the system has avoided the low duty cycle operating region, thus achieving a balance between wide-range output regulation capability and low ripple characteristics.

[0044] Differentiating the input-output relationship, the output voltage error can be approximated as: ; The output voltage error mainly consists of two parts: one part comes from the duty cycle error. Another part comes from input voltage regulation error. .

[0045] Maintain maximum input voltage When the output voltage is low, a low duty cycle is required. If the minimum duty cycle resolution of the PWM controller is... The minimum adjustment step size of the output voltage is approximately: ; The corresponding relative error is: ; When duty cycle D Even when the absolute duty cycle error is very small, Even a small value can significantly amplify the relative output error. In the low output voltage region, relying solely on reducing the duty cycle to regulate voltage can easily lead to a coarser output voltage resolution and decreased regulation accuracy. Maintaining the duty cycle at a preset value in the low power region is preferable. D 0. Output regulation is achieved by linearly adjusting the input voltage. The relative error at this point is: ; Output accuracy is no longer affected by the low duty cycle error amplification effect, but mainly depends on the input voltage regulation accuracy. Since the duty cycle remains within a large and stable range, the effects of PWM resolution, drive delay, and sampling jitter are avoided from being amplified at low duty cycles. The regulation pattern is closer to a continuous analog regulation process, which is beneficial for improving control linearity and output resolution in the low-power region.

[0046] 2. Duty cycle adjustment loop.

[0047] The duty cycle adjustment loop corresponds to the high-power operating range in steps 6 to 8 above. It is the main control loop in this embodiment that enables continued output voltage increase and stable control after the feedback signal used for duty cycle adjustment meets the conduction condition. This loop uses the duty cycle output by the control chip as the main adjustment variable, and changes the energy transfer amount by adjusting the conduction time of the power switching device, thereby achieving closed-loop regulation of the high-voltage output voltage.

[0048] Within this operating range, the input voltage is no longer the primary regulation variable; the main control quantity becomes the inverter stage duty cycle, and the output voltage is mainly varied by adjusting the effective energy transfer per unit switching cycle. This loop uses the output voltage as the control target and the duty cycle as the primary regulation quantity, adjusting the system's power transfer capability by changing the inverter stage's pulse width. Therefore, it is more suitable for wide-range voltage regulation requirements under higher output power conditions. Since the input voltage remains constant at this point, the system's input-side operating conditions are relatively stable, allowing the controller to focus on regulating the inverter stage's energy transfer process, which is beneficial for improving voltage regulation capability and dynamic response speed in the high-power region. Within this range, the duty cycle operates within a relatively effective regulation range, and the input voltage reaches its maximum value. The voltage difference across the linear voltage regulator unit decreases, significantly reducing losses and helping to reduce system heat loss.

[0049] In summary, the segmented voltage regulation control method and high-voltage power supply system for achieving low-ripple and high-precision output of high-voltage power supply in this embodiment have the following technical effects: 1. A segmented control method combining input voltage regulation and duty cycle regulation is adopted. In the low power output range, the duty cycle is kept at a preset fixed value, and the output voltage is closed-loop controlled through the input voltage regulation loop. When the input voltage is adjusted to the upper limit, the input voltage is kept unchanged, and the duty cycle regulation loop takes over the output regulation, thereby realizing wide-range continuous voltage regulation of high voltage output.

[0050] 2. Reduce output ripple by avoiding excessively low duty cycle in the low-power region. In the low-power range, instead of further reducing the duty cycle for voltage reduction, output regulation is achieved by adjusting the input voltage, thereby avoiding the problem of increased output ripple caused by an excessively low duty cycle.

[0051] In another specific embodiment of this application, a high-voltage power supply system includes: a DC-DC converter; a voltage regulation loop for closed-loop control of the input voltage of the DC-DC converter when the operating range of the high-voltage power supply system is a preset low-power operating range, so as to regulate the output voltage of the high-voltage power supply system; otherwise, the input voltage of the DC-DC converter is kept at a preset constant value; and a duty cycle regulation loop for closed-loop control of the pulse width modulation (PWM) duty cycle of the DC-DC converter when the operating range of the high-voltage power supply system is a preset high-power operating range, so as to regulate the output voltage of the high-voltage power supply system; otherwise, the PWM duty cycle of the DC-DC converter is kept at a preset fixed value.

[0052] In one embodiment, the high-voltage power supply system further includes: a front-end linear voltage regulator unit for providing input voltage to the DC-DC converter and for regulating the input voltage of the DC-DC converter under the control of a voltage regulation loop in the low-power operating range.

[0053] In one embodiment, the high-voltage power supply system further includes a feedback network for acquiring a feedback signal that is positively correlated with the output voltage of the high-voltage power supply system and related to a target voltage difference, in order to determine the operating range of the high-voltage power supply system, wherein the target voltage difference is the voltage difference between the output voltage of the high-voltage power supply system and a set reference value; wherein, when the feedback signal is greater than a voltage threshold, it is determined that the high-voltage power supply system is in a high-power operating range; otherwise, it is determined that the high-voltage power supply system is in a low-power operating range.

[0054] Furthermore, the duty cycle adjustment loop is implemented through a PWM control chip. The feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is equipped with a bias network, which provides a preset bias voltage, which is a voltage threshold. When the voltage of the feedback signal rises to a level sufficient to turn on the diode and change the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range. When the voltage of the feedback signal drops to a level insufficient to turn on the diode, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

[0055] Furthermore, the feedback network includes a comparator and a second-order compensation network connected in parallel. The comparator is used to compare the output voltage of the high-voltage power supply system with a set reference value to obtain the target voltage difference. The second-order compensation network is used to compensate the target voltage difference according to the output voltage of the high-voltage power supply system to form a feedback signal.

[0056] Specifically, the second-order compensation network includes two capacitors and one resistor. The resistor and one of the capacitors are connected in series to form the first compensation branch, and the other capacitor alone forms the second compensation branch in parallel with the first compensation branch. The two ends of the first compensation branch and the second compensation branch are connected to the output terminal and the inverting terminal of the comparator, respectively.

[0057] This system is the physical carrier of the above-mentioned methods, and it has all the technical effects of the above-mentioned methods, which will not be elaborated here.

[0058] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0059] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A segmented voltage regulation control method for achieving low-ripple, high-precision output of a high-voltage power supply, applied to a high-voltage power supply system, wherein the high-voltage power supply system includes a front-stage linear voltage regulation unit and a rear-stage DC-DC converter connected to the front-stage linear voltage regulation unit, characterized in that, The segmented voltage regulation control method includes: The output power of the high-voltage power supply system is determined based on its output voltage and output current. The operating range of the high-voltage power supply system is determined based on its output power. The operating range includes a preset low-power operating range and a preset high-power operating range. The output power is determined based on the output voltage and output current of the high-voltage power supply system. When the operating range of the high-voltage power supply system is the preset low-power operating range, the output voltage of the front-stage linear voltage regulation unit is controlled in a closed loop through the input voltage linear regulation loop to adjust the input voltage of the subsequent DC-DC converter, while keeping the pulse width modulation (PWM) duty cycle of the subsequent DC-DC converter at a preset fixed value to achieve low ripple output of the high-voltage power supply. When the operating range of the high-voltage power supply system is the preset high-power operating range, the output voltage of the front-stage linear voltage regulation unit is kept at a preset constant value, and the pulse width modulation (PWM) duty cycle of the rear-stage DC-DC converter is controlled in a closed loop through the duty cycle adjustment loop to adjust the output voltage of the high-voltage power supply system.

2. The segmented voltage regulation control method for achieving low-ripple and high-precision output of a high-voltage power supply according to claim 1, characterized in that, The operating range of the high-voltage power supply system is determined based on its output power, specifically including: A feedback signal is collected. The feedback signal is obtained by a second-order compensation network based on the voltage difference between the output voltage of the high-voltage power supply system and the set reference value, and the current difference between the output current of the high-voltage power supply system and the set reference value. When the feedback signal is greater than the voltage threshold, it is determined that the high-voltage power supply system is in the high-power operating range; otherwise, it is determined that the high-voltage power supply system is in the low-power operating range.

3. The segmented voltage regulation control method for achieving low-ripple and high-precision output of a high-voltage power supply according to claim 2, characterized in that, The duty cycle adjustment loop is implemented by a PWM control chip. The feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is set with a preset bias voltage, which is the voltage threshold. Specifically, when the voltage of the feedback signal rises to a level sufficient to turn on the diode and change the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range; when the voltage of the feedback signal drops to a level insufficient to turn on the diode, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

4. A high-voltage power supply system, characterized in that, include: Pre-amplifier linear voltage regulator unit; The subsequent DC-DC converter is connected to the preceding linear voltage regulator unit; the voltage regulation loop is used to perform closed-loop control on the output voltage of the preceding linear voltage regulator unit when the operating range of the high-voltage power supply system is a preset low-power operating range, so as to regulate the input voltage of the subsequent DC-DC converter; otherwise, the output voltage of the preceding linear voltage regulator unit is kept at a preset constant value. The duty cycle adjustment loop is used to perform closed-loop control of the pulse width modulation (PWM) duty cycle of the downstream DC-DC converter when the operating range of the high-voltage power supply system is a preset high-power operating range, so as to adjust the output voltage of the high-voltage power supply system; otherwise, the PWM duty cycle of the downstream DC-DC converter is kept at a preset fixed value.

5. The high-voltage power supply system according to claim 4, characterized in that, Also includes: A feedback network is used to generate a feedback signal based on the output voltage and output current of the high-voltage power supply system to determine the operating range of the high-voltage power supply system. The feedback network includes a comparator and a second-order compensation network connected in parallel. The comparator is used to compare the output voltage of the high-voltage power supply system with a set reference value to obtain a voltage difference, and to compare the output current of the high-voltage power supply system with a set reference value to obtain a current difference. The second-order compensation network is used to compensate based on the voltage difference and the current difference to form the feedback signal. Specifically, when the feedback signal is greater than the voltage threshold, the high-voltage power supply system is determined to be in the high-power operating range; otherwise, the high-voltage power supply system is determined to be in the low-power operating range.

6. The high-voltage power supply system according to claim 5, characterized in that, The duty cycle adjustment loop is implemented by a PWM control chip. The feedback signal is connected to the error input terminal of the PWM control chip via a diode. The error input terminal is equipped with a bias network, which is used to provide a preset bias voltage, which is the voltage threshold. Specifically, when the voltage of the feedback signal rises to a level sufficient to turn on the diode and change the potential of the error input terminal, the PWM control chip is activated, and the high-voltage power supply system switches to the high-power operating range; when the voltage of the feedback signal drops to a level insufficient to turn on the diode, the PWM control chip is suppressed, and the high-voltage power supply system switches back to the low-power operating range.

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