A high-speed power supply control method with large signal and small signal inner mode control respectively

Abstract

The application discloses a high-speed power supply control method with large-signal and small-signal internal mode control, wherein a power supply reference value and a power supply feedback value are acquired first, and then the power supply reference value and the power supply feedback value are input into a large-signal internal mode and a small-signal internal mode which are set independently; the large-signal internal mode further receives an output signal of the small-signal internal mode, combines the power supply reference value and the power supply feedback value to process the signal, and outputs a control signal to adjust a power supply modulation signal. The small-signal internal mode and the large-signal internal mode are separated by a mathematical method, the large-signal internal mode ensures the response speed of the power supply with wide bandwidth, the small-signal internal mode controls the error in the mathematical model and the disturbance of the actual system, the main component of the output signal is not dragged by the small-signal closed-loop bandwidth, and a parameter dynamic adjustment strategy inhibits the adverse effects caused by the parameter drift of the power supply system. The application is suitable for various power supply application scenarios with strict requirements on dynamic response and steady-state accuracy.

Description

A high-speed power supply control method with separate internal model control for large and small signals Technical Field

[0001] This invention relates to the field of power supply or power electronic converter control technology, specifically to a high-speed power supply control method that uses internal model control for both large and small signals. Background Technology

[0002] As core testing equipment in various industries, power supplies have stringent requirements for dynamic response speed in many application scenarios, which also poses a great challenge to the precise control of power supply response speed.

[0003] In power supply control technology, steady-state accuracy and dynamic response speed are two core indicators that are inherently contradictory: pursuing fast response to large signals often leads to substandard stability, resulting in large steady-state errors; while internal models that emphasize stability and high-precision control usually have low bandwidth, which will significantly drag down the dynamic response rate of the power supply.

[0004] Traditional power supply control methods generally employ a hybrid internal model control strategy combining large-signal and small-signal signals. This strategy aims to simultaneously address steady-state accuracy and dynamic response speed using a single internal model, requiring a constant trade-off between the two during control. This one-size-fits-all approach has an inherent flaw: the hybrid internal model must encompass the entire output signal, and due to bandwidth limitations, it cannot simultaneously meet the demands for high dynamic response and high steady-state accuracy. For example, the PI internal model used for step signal control is a typical example of a hybrid large-signal and small-signal internal model. When its bandwidth setting is too high, dynamic response performance improves, but steady-state error exceeds the allowable range; when the bandwidth setting is too low, the steady-state error meets the requirements, but the dynamic response speed fails to keep up with practical application needs.

[0005] Based on the aforementioned problems in existing technologies, this invention proposes a high-speed power supply control method that uses separate internal model control for large and small signals to address the technical bottlenecks of traditional hybrid internal model control. Furthermore, this invention employs a dynamic parameter adjustment strategy to address system parameter drift, such as the decrease in filter inductor permeability with increasing DC current and frequency, and the fluctuation of filter capacitor value with temperature and ripple frequency, in order to adapt to the challenges posed by system parameter changes to the controller's adaptability. Summary of the Invention

[0006] The purpose of this invention is to provide a high-speed power supply control method that uses separate internal model control for large and small signals, thereby solving the problem of poor dynamic response speed in traditional mixed internal model control of large and small signals.

[0007] To achieve the above objectives, the present invention employs the following technical solutions.

[0008] A high-speed power supply control method with separate large-signal and small-signal internal model control includes the following steps:

[0009] Obtain the power reference value and the power feedback value, and input the power reference value and the power feedback value into the independently set large signal internal model and small signal internal model respectively;

[0010] The large-signal internal mode also receives the output signal of the small-signal internal mode, performs signal processing in combination with the power reference value and the power feedback value, and outputs a control signal to adjust the power modulation signal;

[0011] The large-signal internal model adopts a high-bandwidth configuration to ensure the dynamic response speed of the power supply, while the small-signal internal model adopts a low-bandwidth configuration to suppress mathematical model errors and actual system disturbances.

[0012] A dynamic parameter adjustment strategy is adopted to suppress the effects of power system parameter drift.

[0013] Furthermore, the number of small-signal internal modules is one, two, or more, and each of the small-signal internal modules independently controls different types of errors or disturbances.

[0014] Furthermore, the power supply reference value includes a DC reference value, an AC reference value, or a superposition of a DC reference value and an AC reference value.

[0015] Furthermore, when the power supply reference value is the superposition of the DC reference value and the AC reference value, the small-signal internal model includes a first small-signal internal model, and the input signal of the first small-signal internal model is the difference between the superposition value and the power supply feedback value.

[0016] Furthermore, the small-signal internal model also includes a second small-signal internal model, the input signal of which is the AC component of the AC reference value and the power supply feedback value.

[0017] Furthermore, the first small-signal internal module includes a subtractor, an adder, and a controller G(S); the positive input terminal of the subtractor is connected to the AC reference value, and the negative input terminal is connected to the power feedback value; the first input terminal of the adder is connected to the output terminal of the subtractor, the second input terminal is connected to the DC reference value, the output terminal of the adder is connected to the input terminal of the controller G(S), and the output terminal of the controller G(S) outputs the output control signal of the first small-signal internal module.

[0018] Furthermore, the second small-signal internal model is an AC effective value loop, used to adjust the deviation between the AC reference value and the effective value of the AC component.

[0019] Furthermore, the large-signal internal model includes a voltage outer loop and a current inner loop. The first input terminal of the voltage outer loop is connected to the signal superimposed on the output of the small-signal internal model and the power supply reference value, and the second input terminal is connected to the power supply feedback value. The output terminal of the voltage outer loop is connected to the first input terminal of the current inner loop, the second input terminal of the current inner loop is connected to the power supply current feedback value, and the output terminal of the current inner loop outputs the control signal.

[0020] Furthermore, the bandwidth of the large-signal internal model is higher than that of the small-signal internal model. The bandwidth configuration of the large-signal internal model aims to maximize the dynamic response speed of the power supply, while the bandwidth configuration of the small-signal internal model aims to minimize the steady-state error of the power supply.

[0021] Furthermore, the dynamic parameter adjustment strategy includes the following steps:

[0022] The first step is to inject a sinusoidal signal vi into the output control signal at the output terminal of the large-signal internal mode by sweeping the frequency.

[0023] The second step involves acquiring the output signal vo from the LC filter network and processing the data. vo / vi is calculated at each sinusoidal frequency point to identify the resonant point under the current operating condition. Crossing frequency and phase margin; where, This refers to the filter inductance value in the power supply LC filter network. This refers to the value of the filter capacitor in the power supply LC filter network.

[0024] The third step involves the controller recalculating the control parameters and adjusting the system's zero-pole distribution to bring the cross-frequency range back to normal. The phase margin is 60-70 degrees; among which, The resonant frequency;

[0025] The fourth step is to update the controller parameters, and the dynamic parameter adjustment strategy continuously monitors system parameter drift and adapts to real-time changes in system parameters.

[0026] The advantages of this invention are as follows: The high-speed power supply control method provided by this invention, which uses separate internal model control for large and small signals, avoids the drawback of conventional technologies where steady-state accuracy and transient response speed cannot be simultaneously achieved with mixed internal model control of large and small signals. This method suffers from low steady-state accuracy and low dynamic response speed, especially under high steady-state accuracy requirements. By using separate internal model control for large and small signals, the low bandwidth of the small-signal internal model achieves low steady-state error, while the wide bandwidth of the large-signal internal model achieves high dynamic response speed, thus simultaneously achieving low steady-state error and high response speed. This eliminates the impact of the low bandwidth of the small-signal internal model on the dynamic response speed, significantly improving the power supply's response speed. The dynamic parameter adjustment strategy suppresses the adverse effects of power system parameter drift. Attached Figure Description

[0027] Figure 1 is a schematic diagram of the internal model control principle of the large signal and small signal of the present invention;

[0028] Figure 2 is a schematic diagram of the traditional large-signal and small-signal mixed internal model control principle;

[0029] Figure 3 is an example of internal model control for large and small signals according to Embodiment 1 of the present invention;

[0030] Figure 4 is an example diagram of a large signal internal model, a small signal internal model 1, and a small signal internal model 2 according to Embodiment 2 of the present invention;

[0031] Figure 5 illustrates the parameter dynamic adjustment strategy in Embodiment 3 of the present invention. Detailed Implementation

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0033] Example 1

[0034] This embodiment discloses a high-speed power supply control method with separate large-signal and small-signal internal model controls. The control principle is shown in Figure 1. It includes two independently configured small-signal internal models and a large-signal internal model, namely small-signal internal model 1 and small-signal internal model 2. The large-signal internal model employs a high-bandwidth configuration to ensure the dynamic response speed of the power supply, while the small-signal internal model employs a low-bandwidth configuration to suppress mathematical model errors and actual system disturbances. The bandwidth of the large-signal internal model is significantly higher than that of the small-signal internal model, with the bandwidth configuration aimed at maximizing the dynamic response speed of the power supply. Conversely, the bandwidth configuration of the small-signal internal model aims at minimizing the steady-state error of the power supply.

[0035] During operation, the power reference value and power feedback value are first obtained. The power reference value includes the DC reference value dc_ref and the AC reference value ac_ref. The superposition value of the DC reference value dc_ref and the AC reference value ac_ref is input into the small signal internal modulus 1. The difference between the superposition value and the power feedback value Vo_cy is used as the input signal and input into the small signal internal modulus 1.

[0036] The inputs to the small-signal internal modulus 2 are the AC reference value ac_ref and the power supply feedback value Vo_cy.

[0037] The outputs of small-signal internal mode 1 and small-signal internal mode 2 are superimposed and added to the DC reference value dc_ref and AC reference value ac_ref of the power supply reference value. The difference is then taken as the input signal to the large-signal internal mode. The large-signal internal mode outputs a control signal to adjust the power supply modulation signal.

[0038] Example 2

[0039] Based on Example 1, this embodiment further defines the settings of the small signal internal model 1 and the small signal internal model 2.

[0040] The first small-signal internal module 1 includes a subtractor, an adder, and a controller G(S). The positive input of the subtractor is connected to the AC reference value ac_ref, and the negative input is connected to the power feedback value Vo_cy. The first input of the adder is connected to the output of the subtractor, and the second input is connected to the DC reference value dc_ref. The output of the adder is connected to the input of the controller G(S). The controller G(S) is configured with low bandwidth and outputs the control signal of the small-signal internal module 1.

[0041] The small-signal internal module 2 is an AC RMS loop. Its inputs are the AC reference value ac_ref and the AC component ac_cy in the power supply voltage feedback value Vo_cy. The AC RMS loop adjusts the RMS value deviation between the two and outputs the control signal of the small-signal internal module 2.

[0042] The outputs of small-signal internal model 1 and small-signal internal model 2 are superimposed with the DC reference value dc_ref and the AC reference value ac_ref, and then input to the voltage outer loop. The voltage outer loop processes this signal along with the power supply voltage feedback value Vo_cy, and outputs a current reference signal to the current inner loop. The current inner loop processes the output signal of the voltage outer loop along with the power supply current feedback value Io_cy, and outputs a control signal to adjust the power supply modulation signal, ultimately achieving high-precision and high-speed control of the power supply.

[0043] Example 3

[0044] Parameter dynamic adjustment strategy:

[0045] First: Inject a sinusoidal signal vi into the output control signal at the output terminal of the large-signal internal model by sweeping the frequency.

[0046] Second: Acquire the output signal vo from the LC filter network, process the data, calculate vo / vi at each sinusoidal frequency point, and identify the resonant point under the current operating condition. Crossing frequency and phase margin.

[0047] Third: Controller recalculation: Recalculate the control parameters, adjust the zero-pole distribution of the system, so that the crossover frequency returns to between 1 / 5 and 1 / 10 of the resonant frequency, and the phase margin is around 65 degrees.

[0048] Fourth: Controller parameter update.

[0049] Table 1. Parameter data before drift

[0050]

[0051] Table 2 Data after parameter drift

[0052]

[0053] The system has 5 poles (P=5) and 3 zeros (Z=3). Before adjusting the system parameters for drift, the poles of the LC parameters P3=P4=13.3 kHz, and the crossover frequency is... =1628Hz, phase margin is 65 degrees, the system is stable. After LC parameter drift, poles P3 and P4 change, P3=P4=18.6kHz, the crossover frequency reaches 1100Hz, the phase margin is 23 degrees, and the crossover frequency is... The system exceeded the reliable operating range of 1 / 5 to 1 / 10 of the resonant frequency f, resulting in deteriorated system characteristics. After parameter adjustment, the system regained frequency crossover. =2133Hz, phase margin is 68 degrees, back to normal.

[0054] Finally, it should be noted that 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 high-speed power supply control method with separate internal model control for large and small signals, characterized in that, Includes the following steps: The system acquires power reference and feedback values, and inputs these values ​​into independently configured large-signal and small-signal internal models, respectively. The large-signal internal model also receives the output signal from the small-signal internal model, performs signal processing based on the power reference and feedback values, and outputs a control signal to adjust the power modulation signal. The large-signal internal model employs a high-bandwidth configuration to ensure the dynamic response speed of the power supply, while the small-signal internal model employs a low-bandwidth configuration to suppress mathematical model errors and actual system disturbances. A dynamic parameter adjustment strategy is adopted to suppress the influence of power system parameter drift. This dynamic parameter adjustment strategy includes the following steps: First, a sinusoidal signal vi is injected into the output control signal at the output end of the large-signal internal model; Second, the output signal vo of the LC filter network is acquired and processed, and vo / vi is calculated at each sinusoidal frequency point to identify the resonant point under the current operating condition. Crossing frequency and phase margin; where, This refers to the filter inductance value in the power supply LC filter network. The third step is to recalculate the control parameters of the controller and adjust the zero-pole distribution of the system so that the cross-frequency range returns to normal. The phase margin is 60-70 degrees; among which, The fourth step is to update the controller parameters, and the dynamic adjustment strategy continuously monitors the drift of system parameters and adapts to the real-time changes of system parameters.

2. The high-speed power supply control method according to claim 1, wherein large-signal and small-signal internal model control are respectively characterized in that, The number of small-signal internal modules is one, two, or more, and each small-signal internal module independently controls different types of errors or disturbances.

3. The high-speed power supply control method according to claim 1, characterized in that, The power supply reference value includes a DC reference value, an AC reference value, or a superposition of a DC reference value and an AC reference value.

4. The high-speed power supply control method according to claim 3, wherein large-signal and small-signal internal model control are respectively characterized in that, When the power supply reference value is the superposition of the DC reference value and the AC reference value, the small-signal internal model includes a first small-signal internal model, and the input signal of the first small-signal internal model is the difference between the superposition value and the power supply feedback value.

5. The high-speed power supply control method according to claim 4, wherein large-signal and small-signal internal model control are respectively characterized in that, The small-signal internal model also includes a second small-signal internal model, the input signal of which is the AC component of the AC reference value and the power supply feedback value.

6. The high-speed power supply control method according to claim 4, wherein large-signal and small-signal internal model control are respectively characterized in that, The first small-signal internal model includes a subtractor, an adder, and a controller G(S); the positive input terminal of the subtractor is connected to the AC reference value, and the negative input terminal is connected to the power feedback value; the first input terminal of the adder is connected to the output terminal of the subtractor, the second input terminal is connected to the DC reference value, the output terminal of the adder is connected to the input terminal of the controller G(S), and the output terminal of the controller G(S) outputs the output control signal of the first small-signal internal model.

7. The high-speed power supply control method according to claim 5, wherein large-signal and small-signal internal model control are respectively characterized in that, The second small-signal internal model is an AC effective value loop, used to adjust the deviation between the AC reference value and the effective value of the AC component.

8. The high-speed power supply control method according to claim 1, characterized in that, The large-signal internal model includes a voltage outer loop and a current inner loop. The first input terminal of the voltage outer loop is connected to the signal superimposed on the output of the small-signal internal model and the power supply reference value, and the second input terminal is connected to the power supply feedback value. The output terminal of the voltage outer loop is connected to the first input terminal of the current inner loop, the second input terminal of the current inner loop is connected to the power supply current feedback value, and the output terminal of the current inner loop outputs the control signal.

9. The high-speed power supply control method according to claim 1, wherein large-signal and small-signal internal model control are respectively characterized in that, The bandwidth of the large-signal internal model is higher than that of the small-signal internal model. The bandwidth configuration of the large-signal internal model aims to maximize the dynamic response speed of the power supply, while the bandwidth configuration of the small-signal internal model aims to minimize the steady-state error of the power supply.

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