Load jump dynamic performance optimization method of digital control switch converter

Abstract

The invention provides a load jump dynamic performance optimization method for a digital control switch converter, which relates to the technical field of switch converters and comprises the following steps of: calculating a difference value between an output voltage sampling value of the converter at the current moment and a reference voltage according to the output voltage sampling value, and determining the working state of the current converter; if the working state is dynamic, respectively setting a proportionality coefficient Kp and an integral coefficient Ki in incremental PID control as functions in positive correlation with the difference value; and determining the cumulative number of times that the difference value is greater than a set minimum voltage drop value Vdrop during load skipping, and setting a proportionality coefficient Kpposition in position type PID control as a function which is positively correlated with the difference value and the cumulative number of times. On the premise that the steady-state working stability of the converter is not affected, the load jump dynamic performance of the converter is greatly improved, and the method has the advantages of being simple in implementation method, short in recovery time, small in voltage overshoot and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of switching converters, and in particular to a method for optimizing the load jump dynamic performance of a digitally controlled switching converter. Background Art

[0002] With the development of digital control chips such as DSP and FPGA, digital control has been widely used in power electronic converters. Compared with analog control, digital control has the advantages of simple hardware control circuit, high reliability of control parameters, easy information monitoring and intelligent control, etc. However, in digital control, the processes of sampling feedback signals, regulator calculation, loading modulation signals and updating duty cycle are all processed serially and take a certain amount of time, so digital control delay will occur. Digital control delay will cause a large phase lag. When designing the regulator, it is necessary to reduce the cutoff frequency of the system to ensure that the system phase margin meets the requirements. Reducing the cutoff frequency of the system will cause the dynamic performance of the converter to deteriorate, making the performance of the converter in dynamic processes such as load jump unable to meet the design indicators.

[0003] The most effective way to improve the dynamic performance of load jump is to add load current feedforward. However, when the converter system is more complex, the expression of the load current feedforward coefficient is more complex and difficult to discretize and apply to digital control. On the other hand, this coefficient is closely related to the size of the capacitive load behind it, and is not suitable for occasions where the converter is required to carry a larger capacitive load range.

[0004] Another effective way to improve the dynamic performance of load jump is to add a fast voltage loop, that is, when the voltage changes rapidly, a set of faster dynamic parameters is used to improve the dynamic performance of the converter, which is easier to achieve in analog control. However, in digital control, on the one hand, it is difficult to define the conditions for cutting into and out of the fast voltage loop. If the fast voltage loop is cut out quickly, the effect is not obvious. If the fast voltage loop is cut out slowly, it is very easy to cause overshoot. On the other hand, in order to improve the stability of the converter, digital control usually uses incremental PID for control loop calculation. The output control quantity is only related to the error of the current cycle and the previous two cycles, and the calculation amount is relatively small. When the system has a large error, even if the proportional and integral parameters are increased, it only increases the incremental change of the error, and the final control output change is not obvious, so it is impossible to improve the dynamic performance of the system. Summary of the invention

[0005] In view of this, an embodiment of the present application provides a method for optimizing the load jump dynamic performance of a digitally controlled switching converter. This method can greatly improve the load jump dynamic performance of the converter without affecting the steady-state working stability of the converter, and can also play a good role in situations where the capacitive load demand is large. It has the advantages of simple implementation method, short recovery time, and small voltage overshoot, and can be quickly expanded to various switching converter topology applications.

[0006] The embodiment of the present application provides the following technical solution: a method for optimizing the load jump dynamic performance of a digitally controlled switching converter, comprising:

[0007] Step 1: according to the output voltage sampling value of the converter at the current moment, the difference between the output voltage sampling value and the reference voltage is calculated, and the working state of the current converter is determined according to the difference, and the working state is steady state or dynamic;

[0008] Step 2: If the working state of the converter is dynamic, the proportional coefficient K in the incremental PID control of the converter is p and the integral coefficient K i are respectively set to functions that are positively correlated with the difference;

[0009] And / or, determine that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_position Set as a function that is positively correlated with the difference and the cumulative number of times;

[0010] If the working state of the converter is steady state, it is sent to the original incremental PID control loop to calculate the final output voltage v eaout , skip to step 5 directly;

[0011] Step 3: Calculate the output voltage v of the position PID control respectively eaout_position The output voltage v of the incremental PID control eaout_incremental ;

[0012] Step 4: If the converter output voltage drops, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The larger value of eaout If the converter output voltage overshoots, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The smaller value of eaout ;

[0013] Step 5: Set the final output voltage v eaout The comparison value is sent to the timer to update the duty cycle of the converter in the next cycle;

[0014] Step 6: Repeat steps 1 to 5 in the next switching cycle.

[0015] According to an embodiment of the present application, in step 1, determining the current working state of the converter according to the difference, wherein the working state is a steady state or a dynamic state, includes:

[0016] The difference is compared with the minimum voltage drop value V when the load is set drop , and the minimum voltage overshoot value V when tripping light load rise Make a comparison;

[0017] If the difference is less than the minimum voltage drop value V when the load is set drop , and greater than the minimum voltage overshoot value V when tripping light load rise , the current working state of the converter is steady state; if not, the current working state of the converter is dynamic.

[0018] According to an embodiment of the present application, step 2 also includes:

[0019] If the difference is greater than the set minimum voltage drop value V when jumping overload drop , it is determined that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_position Set as a function that is positively correlated with the difference and the cumulative number of times;

[0020] If the difference is less than the minimum voltage overshoot value V rise , then the proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to a function that is positively correlated with the difference.

[0021] According to an embodiment of the present application, step 1: calculating the difference between the output voltage sampling value and the reference voltage according to the output voltage sampling value of the converter at the current moment, including:

[0022] Let the reference voltage v of position PID control be ref_position Lower than the reference voltage v of incremental PID control re f _ i ncrementa l;

[0023] Calculate the output voltage sampling value and the reference voltage v of the position PID control ref_positionThe difference between , obtain the first difference;

[0024] Calculate the output voltage sampling value and the reference voltage v of the incremental PID control ref_incremental The second difference is obtained by taking the difference of

[0025] According to an embodiment of the present application, step 2 includes:

[0026] The proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to a function positively correlated with the second difference;

[0027] At the same time, it is determined that the first difference is greater than the set minimum voltage drop value V when the load is tripped drop The proportional coefficient K in the position PID control of the converter is p_position The function is set to be positively correlated with the first difference and the cumulative number of times.

[0028] According to an embodiment of the present application, in step 3, the output voltage v of the position PID control is calculated respectively. eaout_position The output voltage v of the incremental PID control eaout_incremental ,include:

[0029] According to the position PID control loop calculation, the output voltage v of the position PID control is obtained. eaout_position , perform loop calculation according to incremental PID control, and obtain the output voltage v of incremental PID control eaout_incremental .

[0030] According to an embodiment of the present application, step 5 also includes:

[0031] The final output voltage v eaout After being limited, the comparison value is sent to the timer to update the duty cycle of the converter in the next cycle.

[0032] According to an embodiment of the present application, step 5 also includes:

[0033] The current moment is recorded as moment k, and the moment in the previous control cycle is moment k-1. Let the output voltage v of the incremental PID control at moment k-1 in the previous control cycle be eaout_incremental(k-1) = Final output voltage v at time k eaout(k) .

[0034] Compared with the prior art, the at least one technical solution adopted in the embodiments of this specification can achieve the following beneficial effects:

[0035] 1. The dynamic performance optimization method proposed in the embodiment of the present invention overcomes the disadvantage of slow dynamic adjustment of incremental PID control. By introducing the position PID control method adjustment loop during load jumping, the voltage drop caused by load jumping can be effectively reduced.

[0036] 2. The core idea of ​​the embodiment of the present invention is the flexible and smooth switching between position PID and incremental PID, which respectively utilizes the good stability of incremental PID and the good dynamic effect of position PID, so that the incremental PID control regulation loop is used in steady-state operation, and the position PID control regulation loop is used in dynamic response, which not only ensures the stability of the converter's steady-state operation, but also improves the converter's dynamic performance.

[0037] 3. The embodiment of the present invention introduces dynamic proportional, integral and differential coefficients based on the original proportional, integral and differential coefficients, which are related to the size of the error signal. When the error is large, the coefficients of the three are large, which is conducive to the rapid adjustment of the converter. When the error is small, the coefficients of the three are small, which is conducive to reducing the overshoot of the adjustment.

[0038] 4. Since the dynamic coefficients of the proportion, integration and differentiation of the position PID of the embodiment of the present invention are positively correlated with the time of the voltage drop, the dynamic performance of the system can be improved well even when the capacitive load carried by the switching converter is large.

[0039] 5. The control method of the embodiment of the present invention is simple to implement and does not require additional hardware circuits. Therefore, it can be embedded in any system without loss and has strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 is a block diagram of a main power circuit and a control circuit of a dynamic performance optimization method according to an embodiment of the present invention;

[0042] Figure 2 is a flow chart of a dynamic performance optimization method according to a first embodiment of the present invention;

[0043] Figure 3 It is a flow chart of the dynamic performance optimization method of the second embodiment of the present invention. DETAILED DESCRIPTION

[0044] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0045] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation methods, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, in the absence of conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work belong to the scope of protection of the present application.

[0046] An embodiment of the present invention provides a method for optimizing the load jump dynamic performance of a digitally controlled switching converter, comprising:

[0047] Step 1: according to the output voltage sampling value of the converter at the current moment, the difference between the output voltage sampling value and the reference voltage is calculated, and the working state of the current converter is determined according to the difference, and the working state is steady state or dynamic;

[0048] Step 2: If the working state of the converter is dynamic, the proportional coefficient K in the incremental PID control of the converter is p and the integral coefficient K i are respectively set to functions that are positively correlated with the difference;

[0049] And / or, determine that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_position Set as a function that is positively correlated with the difference and the cumulative number of times;

[0050] If the working state of the converter is steady state, it is sent to the original incremental PID control loop to calculate the final output voltage v eaout , skip to step 5 directly;

[0051] Step 3: Calculate the output voltage v of the position PID control respectively eaout_position The output voltage v of the incremental PID control eaout_incremental ;

[0052] Step 4: If the converter output voltage drops, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The larger value of eaoutIf the converter output voltage overshoots, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The smaller value of eaout ;

[0053] Step 5: Set the final output voltage v eaout The comparison value is sent to the timer to update the duty cycle of the converter in the next cycle;

[0054] Step 6: Repeat steps 1 to 5 in the next switching cycle.

[0055] The purpose of the present invention is to provide a method for optimizing the load jump dynamic performance of a digital control switching converter to improve the dynamic performance of the converter during load jump. The core feature is that when the converter undergoes load jump, during the period when the output voltage drops, the voltage loop adopts position PID calculation to achieve a faster regulation speed, and during the period when the output voltage rises, the voltage loop smoothly switches back to incremental PID calculation to achieve no overshoot of the output voltage.

[0056] In the embodiment of the present invention, the steady state and dynamic state of the converter respectively describe the working state of the converter under different conditions, wherein the steady state refers to a stable state in which parameters do not change with time, and the dynamic state refers to a process in which parameters change with time.

[0057] In the first embodiment of the present invention, in step 1, determining the current working state of the converter according to the difference, the working state being a steady state or a dynamic state, includes:

[0058] The difference is compared with the minimum voltage drop value V when the load is set drop , and the minimum voltage overshoot value V when tripping light load rise Make a comparison;

[0059] If the difference is less than the minimum voltage drop value V when the load is set drop , and greater than the minimum voltage overshoot value V when tripping light load rise , the current working state of the converter is steady state; if not, the current working state of the converter is dynamic.

[0060] In the first embodiment of the present invention, step 2 further includes:

[0061] If the difference is greater than the set minimum voltage drop value V when jumping overload drop , it is determined that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_positionSet as a function that is positively correlated with the difference and the cumulative number of times;

[0062] If the difference is less than the minimum voltage overshoot value V rise , then the proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to a function that is positively correlated with the difference.

[0063] In the second embodiment of the present invention, step 1: calculating the difference between the output voltage sampling value and the reference voltage according to the output voltage sampling value of the converter at the current moment, comprises:

[0064] Let the reference voltage v of position PID control be ref_position Lower than the reference voltage v of incremental PID control ref_incremental ; Calculate the output voltage sampling value and the reference voltage v of the position PID control ref_position Calculate the output voltage sampling value and the reference voltage v of the incremental PID control ref_incremental The second difference is obtained by taking the difference of

[0065] In the second embodiment of the present invention, step 2 includes: setting the proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to be a function positively correlated with the second difference; at the same time, it is determined that the first difference is greater than the set minimum voltage drop value V when the load is tripped drop The proportional coefficient K in the position PID control of the converter is p_position The function is set to be positively correlated with the first difference and the cumulative number of times.

[0066] In a specific implementation of the embodiment of the present invention, in step 3, loop calculation is performed according to the position PID control to obtain the output voltage v of the position PID control. eaout_position , perform loop calculation according to incremental PID control, and obtain the output voltage v of incremental PID control eaout_incremental .

[0067] In a specific implementation of the embodiment of the present invention, step 5 also includes: setting the final output voltage v eaout After being limited, the comparison value is sent to the timer to update the duty cycle of the converter in the next cycle.

[0068] In a specific implementation of the embodiment of the present invention, step 5 further includes: recording the current moment as moment k, then the moment in the previous control cycle as moment k-1, and setting the output voltage v of the incremental PID control at moment k-1 in the previous control cycle aseaout_incremental(k-1) = Final output voltage v at time k eaout(k) .

[0069] Figure 1 This is a block diagram of the main power circuit and control circuit of a method for optimizing the load jump dynamic performance of a digitally controlled switching converter according to an embodiment of the present invention. It should be noted that this embodiment is only used to illustrate the working principle, and for the sake of simplicity, the specific implementation of some functional circuits such as the sampling circuit and the driving circuit are omitted. Figure 1 As shown, the main power topology adopts Buck converter, where Q is the Buck main control switch tube and D is the Buck freewheeling diode.

[0070] Embodiment 1:

[0071] This embodiment provides a flow chart of a method for optimizing the load jump dynamic performance of a digitally controlled switching converter. Figure 2 As shown, here we take the Buck converter under single voltage loop control as an example, including the following steps:

[0072] Step 1: Record the current time as time k, then the time in the previous control cycle is time k-1, according to the output voltage sampling value v at the current time os (k), calculate its difference with the reference voltage v ref The difference v error (k) = v ref -v os (k).

[0073] Step 2: If the difference v error (k) is less than the minimum voltage drop value V when setting the load trip drop , and greater than the minimum voltage overshoot value V when tripping light load rise (The V rise When the voltage is overshooting, it is negative), which means that the converter is working in a steady state and will not trigger the fast voltage loop, so jump directly to step 4;

[0074] If the difference v error (k) greater than V drop , indicating that the converter jumps from light load to heavy load at this time, and the output voltage drops greatly. Therefore, it is necessary to use the position PID to quickly adjust the duty cycle. Therefore, the proportional coefficient K in the position PID is p_factor_position Set to the difference and the difference is greater than V drop The cumulative number of times is positively correlated;

[0075] In one embodiment, the voltage drop count value dropcnt can be increased by 1 each time, that is, dropcnt(k)=dropcnt(k-1)+1, and the proportional coefficient K in the position PID is p_factor_position Set to Kp_factor_position =10+(v error (k)-V drop )+dropcnt(k).

[0076] If the difference v error (k) is less than V rise , indicating that the converter jumps from heavy load to light load at this time, and the output voltage overshoot is large, so the proportional coefficient K in the incremental PID p_factor and the integral coefficient K i_factor Set as a function that is positively correlated with the difference;

[0077] In one embodiment, they can be set to K p_factor =10-8v error (k), K i_factor =1-8(v error (k)-V rise ), then skip to step 4.

[0078] Step 3: According to equation (1), use position PID control to calculate the loop and get the output v eaout_position (k).

[0079] v eaout_position (k) = K p_factor_position K p v error (k) (1)

[0080] In this embodiment, since only the proportional term in the position PID control is used, there is no need to store the integral term each time, and the position PID regulation loop only needs to be called when the load changes, which reduces the running time of the program.

[0081] Step 4: According to formula (2), use incremental PID control to calculate the loop and obtain the output v eaout_incremental (k).

[0082]

[0083] In the formula, K p , K i , K d are the basic proportional coefficient, integral coefficient, and differential coefficient obtained by discretizing the digital control system, respectively. p_factor , K i_factor , K d_factor For incremental PID dynamic adjustment, K needs to be increased p , K i , K d The corresponding multiples.

[0084] Step 5: If the difference is less than V drop , jump to step 6; if the difference is greater than Vdrop , then take the incremental PID output v eaout_incremental (k) and position PID output v eaout_position The larger value in (k) is used as the final output voltage v eaout In this embodiment, once the output voltage starts to rise, v error (k) will decrease, that is, formula (1) will decrease, and formula (2) will continue to increase due to the existence of the integral term, so formula (2) will naturally be greater than formula (1), that is, the position PID is smoothly switched back to the incremental PID calculation loop, so it will not affect the stability of the converter.

[0085] Step 6: Set the final output voltage v eaout After limiting, we get v eaout (k) The comparison value is sent to the timer to update the duty cycle of the Buck converter in the next cycle. eaout_incremental (k-1)=v eaout (k).

[0086] Step 7: Repeat steps 1 to 7 in the next switching cycle.

[0087] Embodiment 2:

[0088] This embodiment provides a flow chart of a method for optimizing the load jump dynamic performance of a digitally controlled switching converter. Figure 3 As shown in the above working principle, it can be seen that the key to the control method of the present invention is to realize the natural switching between incremental PID control and position PID control when the converter is in steady state and dynamic operation. Therefore, the reference voltage v of the position PID control can be ref_position Slightly lower than the reference voltage v of the incremental PID ref_incremental , then there is no need to judge the difference and V drop and V rise The specific implementation steps can be simplified as follows:

[0089] Step 1: Record the current moment as moment k, then the moment in the previous control cycle is moment k-1, and the moment in the previous two control cycles is moment k-2. According to the output voltage sampling value v at the current moment os (k), respectively calculate its relative voltage to the reference voltage v ref_position 、v ref_incremental The difference v error_position (k), v error_incremental (k), namely:

[0090] v error_position (k) = v ref_position -v os (k) (3)

[0091] verror_incremental (k) = v ref_incremental -v os (k) (4)

[0092] In the formula, v ref_position is the reference voltage for position PID control, v ref_incremental is the reference voltage of the incremental PID, and v ref_position <v ref_incremental .

[0093] Step 2: Change the proportional coefficient K in the position PID p_factor_position Set to the difference and the difference is greater than V drop The cumulative number of times is positively correlated;

[0094] In one embodiment, the voltage drop count value dropcnt is incremented by 1 each time, that is, dropcnt(k)=dropcnt(k-1)+1, and the proportional coefficient K in the position PID is p_factor_position Set to K p_factor_position =1+v error (k)+dropcnt(k).

[0095] The proportional coefficient K in the incremental PID p_factor and the integral coefficient K i_factor Set as a function that is positively correlated with the difference;

[0096] In one embodiment, they can be set to K p_factor =|1-8v error (k)|,K i_factor =|1-6v error (k)|.

[0097] Step 3: According to equation (5), use position PID control to calculate the loop and get the output v eaout_position (k).

[0098]

[0099] In the formula, K p_factor_postion Increase K for position PID dynamic adjustment p The corresponding multiple, v i (k-1) is the sum of all integral terms before the position PID, as shown in equation (6),

[0100]

[0101] Step 4: According to formula (7), use incremental PID control to calculate the loop and obtain the output v eaout_incremental (k).

[0102]

[0103] In the formula, K p , K i , K d are the basic proportional coefficient, integral coefficient, and differential coefficient obtained by discretizing the digital control system, respectively. p_factor , K i_factor , K d_factor For incremental PID dynamic adjustment, K needs to be increased p , K i , K d The corresponding multiple, in this embodiment, needs to limit K p_factor , K i_factor , K d_factor The minimum value is 1.

[0104] Step 5: Take the incremental PID output v eaout_incremental (k) and position PID output v eaout_position The larger value in (k) is used as the final output voltage v eaout In this embodiment, since v ref_position <v ref_incremental After the output voltage returns to the reference set by the position PID, the position PID output will naturally decrease, while the incremental PID output will continue to increase because it has not reached its set reference until the position PID is smoothly switched back to the incremental PID calculation loop, so it will not affect the stability of the converter.

[0105] Step 6: Set the final output voltage v eaout After limiting, we get v eaout (k) The comparison value is sent to the timer to update the duty cycle of the Buck converter in the next cycle. eaout_incremental (k-1)=v eaout (k).

[0106] Step 7: Repeat steps 1 to 7 in the next switching cycle.

[0107] Although the optimization method of the present invention takes Buck converter as an example, the method can be extended to any other power electronic converter under any other digital control. Meanwhile, the closed-loop control can adopt single voltage loop, average current control or other available control methods.

[0108] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A method for optimizing the load jump dynamic performance of a digitally controlled switching converter, characterized in that: include: Step 1: according to the output voltage sampling value of the converter at the current moment, the difference between the output voltage sampling value and the reference voltage is calculated, and the working state of the current converter is determined according to the difference, and the working state is steady state or dynamic; Step 2: If the working state of the converter is dynamic, the proportional coefficient K in the incremental PID control of the converter is p and the integral coefficient K i are respectively set to functions that are positively correlated with the difference; And / or, determine that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_position Set as a function that is positively correlated with the difference and the cumulative number of times; If the working state of the converter is steady state, it is sent to the original incremental PID control loop to calculate the final output voltage v eaout , skip to step 5 directly; Step 3: Calculate the output voltage v of the position PID control respectively eaout_position The output voltage v of the incremental PID control eaout_incremental ; Step 4: If the converter output voltage drops, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The larger value of eaout If the converter output voltage overshoots, take the output voltage v of the position PID control eaout_position The output voltage v of the incremental PID control eaout_incremental The smaller value of eaout ; Step 5: Set the final output voltage v eaout The comparison value is sent to the timer to update the duty cycle of the converter in the next cycle; Step 6: Repeat steps 1 to 5 in the next switching cycle.

2. The method according to claim 1, characterized in that: In step 1, the current working state of the converter is determined according to the difference, and the working state is steady state or dynamic state, including: The difference is compared with the minimum voltage drop value V when the load is set drop , and the minimum voltage overshoot value V when tripping light load rise Make a comparison; If the difference is less than the minimum voltage drop value V when the load is set drop , and greater than the minimum voltage overshoot value V when tripping light load rise , the current working state of the converter is steady state; if not, the current working state of the converter is dynamic.

3. The method according to claim 2, characterized in that Step 2 also includes: If the difference is greater than the minimum voltage drop value V when the load is set drop , it is determined that the difference is greater than the set minimum voltage drop value V when the load is jumped drop The proportional coefficient K in the position PID control of the converter is p_position Set as a function that is positively correlated with the difference and the cumulative number of times; If the difference is less than the minimum voltage overshoot value V rise , then the proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to a function that is positively correlated with the difference.

4. The method according to claim 1, characterized in that Step 1: Calculate the difference between the output voltage sampling value and the reference voltage according to the output voltage sampling value of the converter at the current moment, including: Let the reference voltage v of position PID control be ref_position Lower than the reference voltage v of incremental PID control re f _ incremental; Calculate the output voltage sampling value and the reference voltage v of the position PID control ref_position The first difference is obtained; Calculate the output voltage sampling value and the reference voltage v of the incremental PID control ref_incremental The second difference is obtained by taking the difference of 5. The method according to claim 4, characterized in that Step 2 includes: The proportional coefficient K in the incremental PID control of the converter p and the integral coefficient K i is set to a function positively correlated with the second difference; At the same time, it is determined that the first difference is greater than the set minimum voltage drop value V when the load is tripped drop The proportional coefficient K in the position PID control of the converter is p_position The function is set to be positively correlated with the first difference and the cumulative number of times.

6. The method according to claim 1, characterized in that In step 3, the output voltage v of the position PID control is calculated respectively. eaout_position The output voltage v of the incremental PID control eaout_incremental ,include: According to the position PID control loop calculation, the output voltage v of the position PID control is obtained. eaout_position , perform loop calculation according to incremental PID control, and obtain the output voltage v of incremental PID control eaout_incremental .

7. The method according to claim 1, characterized in that Step 5 also includes: The final output voltage v eaout After being limited, the comparison value is sent to the timer to update the duty cycle of the converter in the next cycle.

8. The method according to claim 1, characterized in that Step 5 also includes: The current moment is recorded as moment k, and the moment in the previous control cycle is moment k-1. Let the output voltage v of the incremental PID control at moment k-1 in the previous control cycle be eaout_incremental(k-1) = Final output voltage v at time k eaout(k) .

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