Power supply device control method

Abstract

The power supply device control method provided by the invention is applied to the power supply device for supplying energy to a heavy-load and light-load periodically-changing load, and the working state of the power supply device comprises a first state and a second state which are continuously switched. The control unit predicts the switching moment of switching from the current working state to the next different working state, the control unit sends a control instruction used for adjusting the output voltage of the power supply device earlier than the corresponding predicted next switching moment, and active control is involved before the working states are switched, so that the dynamic performance of the power supply device can be effectively improved, and the power supply efficiency is improved. And the fluctuation range of the output voltage is reduced.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and particularly to a control method for a power supply device. Background Art

[0002] Power supply devices, such as switching power supplies, are usually used as the power sources for various electrical equipment to convert unregulated AC or DC input voltages into regulated AC or DC output voltages. Due to the need to adapt to different working conditions, the performance requirements for the dynamic response of the power supply are getting higher and higher. Good dynamic effects require the power supply device to have small voltage changes and voltage recovery times. When the power demand of the load suddenly increases or decreases significantly, the output voltage of the power supply device will experience undervoltage or overvoltage at this time, which not only fails to meet the needs of the load but also easily causes damage to the load.

[0003] In the prior art, in order to improve the dynamic performance of the power supply device in response to changing loads, the common control methods are voltage loop or current loop. However, whether it is voltage loop control or current loop control, they both intervene in the control only after the output voltage changes suddenly. When the control signal acts on the switching unit, the amplitude of the output voltage has already changed significantly, and the voltage spike has reached a relatively high level. Therefore, this control method has a certain lag and can only limitedly improve the dynamic performance of the power supply device.

[0004] With the continuous improvement of the requirements for power supply quality at the load end, how to improve the dynamic response ability of the power supply device and reduce the fluctuation range of the output voltage is an urgent problem to be solved. Summary of the Invention

[0005] This application provides a control method for a power supply device to solve at least one of the defects existing in the above prior art.

[0006] In a first aspect, this application provides a control method for a power supply device, providing a power supply device, and the power supply device includes a control unit;

[0007] The working state of the power supply device includes continuously switching state one and state two;

[0008] Adjacent state one and state two form a cycle. In each cycle, state one switches to state two in the current cycle at the first switching moment; in each cycle, state two switches to state one in the next cycle at the second switching moment;

[0009] The control method includes the following steps:

[0010] Obtain the current working state of the power supply device;

[0011] Predict the switching moment of switching from the current working state to the next different working state according to the current working state of the power supply device;

[0012] The control unit issues an instruction earlier than a corresponding predicted next switching moment, and the instruction is used to adjust the output voltage of the power supply device.

[0013] In the above technical solution, for a load with a periodically changing power demand, the power supply device predicts in advance the moment of mutual switching between heavy load and light load through the working state of the power supply device, so as to control the power supply device in advance. Compared with the passive and lagging disadvantages of the traditional control scheme, the control method disclosed in the present invention has the advantages of being active and in advance, which can greatly improve the dynamic performance of the power supply device and reduce the fluctuation range of the output voltage.

[0014] Optionally, the step of predicting the corresponding next switching moment according to the current working state of the power supply device includes:

[0015] Obtain the starting moment of the current working state;

[0016] Obtain the duration of the working state of the power supply device that is the same as the current working state in the previous cycle;

[0017] The corresponding next switching moment predicted by the current working state is the sum of the starting moment of the current working state and the duration of the working state of the power supply device that is the same as the current working state in the previous cycle.

[0018] Optionally, the obtaining the starting moment of the current working state includes:

[0019] If the current working state is State One, the starting moment of the current working state is the second switching moment in the previous cycle;

[0020] If the current working state is State Two, the starting moment of the current working state is the first switching moment in the current cycle.

[0021] Optionally, the steps of obtaining the duration of State One and the duration of State Two include:

[0022] The control unit obtains the working state of the power supply device multiple times at a preset time interval;

[0023] The control unit determines whether the working states of the power supply device at the a-th time and the (a + 1)-th time are the same;

[0024] If the working states of the power supply device at the a-th time and the (a + 1)-th time are different, start a counting loop, and the count value is x, where x ≥ 0, and the initial value of the count value x is 0;

[0025] Loop and execute the following steps until it is determined that the operating states of the power supply device in two adjacent times are different. Then, end the loop and obtain the current count value X, where X = x + n and n is the number of loop executions:

[0026] Obtain the operating states of the power supply device in two adjacent times;

[0027] Determine whether the operating states of the power supply device in two adjacent times are the same;

[0028] If the operating states of the power supply device in two adjacent times are the same, increment the count value x and return to obtain the operating states of the power supply device in two adjacent times again;

[0029] If the (a + 1)-th obtained operating state of the power supply device is State 1, the duration of State 1 is equal to the product of the current count value X and the preset time interval; if the (a + 1)-th obtained operating state of the power supply device is State 2, the duration of State 2 is equal to the product of the current count value X and the preset time interval.

[0030] Optionally, the step of the control unit issuing an instruction earlier than the predicted next switching moment includes:

[0031] If the current operating state is State 1, the control unit issues the instruction at the first instruction moment, and the first instruction moment is the predicted first switching moment minus the first time;

[0032] If the current operating state is State 2, the control unit issues the instruction at the second instruction moment, and the second instruction moment is the predicted second switching moment minus the second time.

[0033] Optionally, both the first time and the second time are fixed values.

[0034] Optionally, the step of the control unit issuing the instruction at the first instruction moment includes:

[0035] The step of the control unit issuing the instruction at the first instruction moment includes:

[0036] Obtain the current moment of the current operating state;

[0037] Determine the magnitude relationship between the current moment and the first instruction moment;

[0038] If the current moment is less than or equal to the first instruction moment, return to obtain the current moment of the current operating state again; if the current moment is greater than the first instruction moment, the control unit issues the instruction;

[0039] The step of the control unit issuing the second instruction at the second instruction moment includes:

[0040] Obtain the current moment of the current working state;

[0041] Judge the magnitude relationship between the current moment and the second instruction moment;

[0042] If the current moment is less than or equal to the second instruction moment, return to obtain the current moment of the current working state again; if the current moment is greater than the second instruction moment, the control unit issues the instruction.

[0043] Optionally, the absolute value of the difference between the output current of the power supply device when it works in state one and the output current when it works in state two is greater than a preset current threshold.

[0044] Optionally, the output current of the power supply device when it works in state one is less than the output current when it works in state two.

[0045] Optionally, if the current working state of the power supply device is state one, the instruction is used to increase the output voltage of the power supply device;

[0046] If the current working state of the power supply device is state two, the instruction is used to decrease the output voltage of the power supply device.

[0047] Optionally, obtain a preset target voltage value included in the power supply device;

[0048] If the current working state of the power supply device is state one, the instruction is used to make the output voltage of the power supply device equal to the sum of the preset target voltage value and a first gain;

[0049] If the current working state of the power supply device is state two, the instruction is used to make the output voltage of the power supply device equal to the difference between the preset target voltage value and a second gain.

[0050] Optionally, both the first gain and the second gain are fixed values.

[0051] Optionally, both the first gain and the second gain are set multiples of the difference between the maximum output voltage and the minimum output voltage of the power supply device.

[0052] Optionally, the output current of the power supply device is direct current.

[0053] A control method for a power supply device provided by the present application. This method is applied to the power supply device. The working state of the power supply device includes state one and state two that are continuously switched. An adjacent state one and state two form a cycle. During the operation of the power supply device, the control unit obtains the current working state of the power supply device, predicts the switching moment from the current working state to the next different working state according to the current working state of the power supply device, and issues an instruction before the corresponding predicted next switching moment to adjust the output voltage of the power supply device. By intervening in the active control before the working state is switched, the dynamic performance of the power supply device can be effectively improved, and the fluctuation range of the output voltage can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] The accompanying drawings herein are incorporated into and constitute a part of this specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0055] Figure 1 It is a waveform diagram of the output voltage generated by the power supply device applying traditional control according to an exemplary embodiment of the present application;

[0056] Figure 2 It is a schematic flowchart of the control method for the power supply device according to an exemplary embodiment of the present application;

[0057] Figure 3 It is a schematic flowchart of the switching moment prediction method according to an exemplary embodiment of the present application;

[0058] Figure 4 It is a schematic flowchart of the method for determining the duration of the state according to an exemplary embodiment of the present application;

[0059] Figure 5A It is a schematic flowchart of the method for determining the sending moment of the first instruction according to an exemplary embodiment of the present application;

[0060] Figure 5B It is a schematic flowchart of the method for determining the sending moment of the second instruction according to an exemplary embodiment of the present application;

[0061] Figure 6 It is a waveform diagram of the output voltage generated by the power supply device applying the power supply device control method according to an exemplary embodiment of the present application.

[0062] Through the above-mentioned accompanying drawings, the clear embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These accompanying drawings and the textual descriptions are not intended to limit the scope of the concept of the present application in any way, but to explain the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0063] Exemplary embodiments will be described in detail herein, and examples thereof are shown in the accompanying drawings. When the following description refers to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0064] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances. For example, without departing from the scope of this article, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information.

[0065] Depending on the context, the word "if" as used herein can be interpreted as "when" or "while" or "in response to a determination".

[0066] Furthermore, as used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context indicates otherwise.

[0067] It should be further understood that the terms "comprising", "including" indicate the presence of features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups.

[0068] The term "or" and "and / or" used herein are interpreted inclusively and mean any one or any combination. Thus, "A, B or C" or "A, B and / or C" means "any one of the following: A; B; C; A and B; A and C; B and C; A, B and C". An exception to this definition only occurs when the combination of elements, functions, steps or operations is inherently mutually exclusive in some way.

[0069] To solve the technical problems mentioned in the background art, the present invention discloses a new method for controlling a power supply device. The control method disclosed by the present invention is mainly applied to loads with periodically changing power demands, hereinafter referred to as heavy loads and light loads. By predicting in advance the moment of mutual switching between heavy loads and light loads, the power supply device can be controlled in advance. Compared with the passive and lagging disadvantages of traditional control schemes, the control method disclosed by the present invention has the advantages of being active and advanced, which can greatly improve the dynamic performance of the power supply device and reduce the fluctuation range of the output voltage.

[0070] According to the different power requirements of the load under different working conditions, the output current of the power supply device also changes accordingly. Since the response speed of the output current to the load change is relatively fast, the magnitude of the output current can be used to represent the working state of the load. When the output current is small, it means the load is working in the light load mode; when the output current is large, it means the load is working in the heavy load mode.

[0071] Figure 1 Fig. 4 shows the waveform diagram of the output voltage generated by the power supply device applying traditional control. When the output voltage is stable, its magnitude is Vo. At moment m, the output current I_load of the power supply device jumps from a small current to a large current, indicating that the load switches from the light load to the heavy load. At this time, the output voltage has already started to drop. In the traditional control method, such as voltage loop control, only when the drop amplitude of the output voltage exceeds a certain threshold, for example, when the output voltage drops by more than Va, will the voltage loop intervene in the voltage control. Until moment n, the drive signal (PWM) of the switching unit receives the control result of the voltage loop and changes. At this time, the output voltage has already dropped to Vmin, and then it will gradually rise to Vo. Figure 1 It can be seen that when the load switches from the light load to the heavy load, the time required for the drive signal PWM to change is (m - n), and the drop amplitude of the output voltage is (Vmin - Vo). It can be seen that the traditional voltage loop control has inherent defects, such as long response time, large change in the output voltage amplitude, and its dynamic performance is difficult to meet the requirements. Similarly, when the output current I_load drops from a large current to a small current, it means that the load switches from the heavy load to the light load. Figure 1 Similarly, it can be seen that when the output voltage rises to Vmax, the drive signal PWM changes, such as frequency modulation control, and then the output voltage drops from Vmax to Vo. Therefore, Figure 1 it can be found that when the traditional control method is applied to a load with mutual switching between heavy load and light load, the dynamic performance of the power supply device is poor, which is likely to affect the stability of the load and even damage the load.

[0072] However, the control method disclosed in the present invention can predict in advance the moment of mutual switching between heavy load and light load, and thus control the power supply device in advance. Compared with the passive and lagging defects of the traditional control scheme, the control method disclosed in the present invention has the advantages of being active and in advance, which can greatly improve the dynamic performance of the power supply device and reduce the fluctuation range of the output voltage.

[0073] When the load makes periodic and continuous switching between heavy load and light load, the power supply device that powers it will also have two continuously switching working states, such as continuously switching state one and state two. State one and state two can correspond to the light load and heavy load of the load, or state one and state two can respectively correspond to the heavy load and light load of the load. The present invention does not limit this. In the present invention, for the convenience of description, state one and state two correspond to the light load and heavy load of the load, that is, when the power supply device works in state one, it outputs a small current, and when the power supply device works in state two, it outputs a large current. Moreover, adjacent state one and state two form a cycle of the power supply device. In the actual process, since it is difficult to make the output current a constant value, in the case of stable output, there will also be a certain ripple in the output current. Therefore, only when the change in the output current is greater than a preset current threshold will it be determined that the working state of the power supply device has switched.

[0074] In each cycle, it includes a first switching moment and a second switching moment. At the first switching moment, the power supply device switches from state one to state two, and at the second switching moment, the power supply device switches from state two to state one of the next cycle.

[0075] Since the power demand of the load changes periodically, it is possible to predict the switching moments of the light load and heavy load of the load in advance, and let the power supply device make corresponding preparations to cope with the jump or drop of the output voltage in advance, so as to avoid large fluctuations in the output voltage.

[0076] In actual operation, due to the periodic change of the power demand of the load leading to the periodic change of the working state of the power supply device, it is possible to directly predict the switching moment of the power supply device in each cycle, so that the control unit in the power supply device issues an instruction earlier than the predicted switching moment to adjust the output voltage of the power supply device in advance.

[0077] In some embodiments, the control method includes the following steps, as Figure 2 shown, where the labels before the steps are only a preferred order and are not actually limited to this:

[0078] S01: Obtain the current working state of the power supply device;

[0079] S02: According to the current working state of the power supply device, predict the switching moment to the next different working state;

[0080] S03: According to the predicted switching moment, the control unit issues a control instruction earlier than the predicted switching moment to actively adjust the output voltage of the power supply device.

[0081] For step S01:

[0082] In some embodiments, the sampling unit in the power supply device continuously samples the output current of the power supply device at a certain sampling frequency. Once the difference between the output currents of two consecutive samplings is greater than the set current threshold, it is determined that the power supply device has switched its working state. And before the next switch, the control unit in the power supply device continuously records the current working state. For example, when the difference between the output currents of two consecutive samplings is greater than the set current threshold, then judge the magnitudes of the currents in the two samplings. If the output current of the previous sampling is less than that of the subsequent sampling, it means that the working state of the power supply device has switched from state one to state two. Before the next switch occurs, the control unit will always record the working state of the power supply device as state two. When step S02 needs to be performed, the current working state of the power supply device can be directly obtained from the control unit as state two.

[0083] In some other embodiments, the working state of the power supply device can be obtained by sampling the output current of the power supply device in real time. For example, a standard current value can be set. When the real-time output current obtained by sampling is less than the standard current value, it is determined that the current working state is state one and the load is in a light load working state. When the real-time output current obtained by sampling is greater than the standard current, it is determined that the current working state is state two and the load is in a heavy load working state.

[0084] For step S02:

[0085] In some embodiments, after obtaining the current working state of the power supply device, the switching moment to the next different working state can be predicted according to the current working state. For example, if the current working state is state one, then predict the first switching moment to state two. If the current working state is state two, then predict the second switching moment to state one.

[0086] For step S03:

[0087] In some embodiments, the control unit issues an action instruction ahead of the predicted switching moment to actively control the output voltage of the power supply device in advance. For example, if the current state is state one, the predicted switching moment is the predicted first switching moment, which means that the load will jump from light load to heavy load at the predicted first switching moment and the output voltage will drop at the predicted first switching moment. Therefore, the control unit will actively increase the output voltage ahead of the predicted first switching moment to prevent the output voltage from dropping to a lower voltage value after the actual arrival of the first switching moment. For example Figure 1 shown as Vmin. Similarly, if the current state is state two, the control unit will actively reduce the output voltage ahead of the predicted second switching moment to prevent the output voltage from rising to a higher voltage value after the actual arrival of the second switching moment. For example Figure 1 shown as Vmax.

[0088] By actively controlling the output voltage in advance, the fluctuation range of the output voltage of the power supply device can be made significantly smaller than that of the traditional passive control method.

[0089] The following combines Figure 3 to illustrate the specific implementation method of the above step S02.

[0090] For step S02, as Figure 3 shown, it specifically includes the following steps:

[0091] S021: Obtain the starting moment of the current working state;

[0092] S022: Obtain the duration when the power supply device was in the same working state as the current one last time;

[0093] S023: Calculate the predicted switching moment corresponding to the current working state.

[0094] The following combines Figure 6 to illustrate the above steps:

[0095] Figure 6 Schematically shows two working cycles of the power supply device. For the convenience of explanation, 0 - Y1 is the first cycle, and Y1 - Y2 is the second cycle. Among them, X1 represents the first switching moment in the first cycle, Y1 represents the second switching moment in the first cycle. Similarly, X2 represents the first switching moment in the second cycle, and Y2 represents the second switching moment in the second cycle. Among them, 0, X1, Y1, X2, Y2, and C all represent moments, Figure 6 where T1, T2, t1, and t2 all represent time.

[0096] After the process of step S01, the current working state of the power supply device may be at Figure 6 any position shown. For the convenience of explanation, assume that after the process of step S01, the current working state of the power supply device is the state one corresponding to the moment C, and this state is located in the second working cycle Y1 - X2;

[0097] Then step S021 can confirm that the starting moment of the current working state is the second switching moment Y1 in the first cycle;

[0098] Step S022: According to Figure 6 it can be seen that when the power supply device was in state one last time, it was within the interval 0 - X1 of the first cycle. It can be seen from the figure that its duration is T1;

[0099] In step S023, based on the start time Y1 of the current working state and the duration T1 of the previous state one, it can be predicted that the power supply device will switch to state two at the moment (Y1 + T1), that is, the predicted first switching moment will occur at the moment (Y1 + T1).

[0100] If after the process of step S01, the current working state of the power supply device is state two and it is at the second working cycle X2 - Y2, then the corresponding current state start time is X2, and the duration of the previous stay in state two is the duration T2 of the interval X1 - Y1 in the first cycle. Then the predicted second switching moment will occur at the moment (X2 + T2).

[0101] The following combines Figure 4 to further illustrate how to obtain the duration of state one or state two.

[0102] As mentioned before, the sampling unit in the power supply device will continuously sample the output current of the power supply device at a certain sampling frequency or a preset time interval m. Once the difference between the output currents of two consecutive samplings is greater than the set current threshold, it is determined that the power supply device has switched its working state. If the difference between the two consecutive output currents is less than or equal to the set current threshold, it means that the power supply device maintains the previous working state. Based on this scheme, there is a count value x in the control unit, and the initial value of the count value x is 0, which is used to obtain the duration of state one or state two. The specific method is as follows:

[0103] Obtain the working states of the power supply device in two consecutive adjacent times. For the sake of explanation, such as the a - th time and the (a + 1)-th time. If the difference between the output currents of the a - th time and the (a + 1)-th time is greater than the set current threshold, then the following steps are cyclically executed until the difference between two consecutive output currents, such as the (a + n)-th time and the (a + n + 1)-th time, is greater than the set current threshold again:

[0104] S0221: Obtain the working states of the power supply device in two consecutive adjacent times;

[0105] S0222: Determine whether the working states of the power supply device in two consecutive adjacent times are the same;

[0106] S0223: If the working states of the power supply device in two consecutive adjacent times are the same, then the count value x is incremented, and return to step S0221;

[0107] For example, if the difference between the output currents of the (a + 1)-th and (a + 2)-th samplings is less than or equal to a set current threshold, that is, the operating states of the power supply device at the (a + 1)-th and (a + 2)-th times are the same, then the value of x is incremented by 1, and the difference between the output currents of the (a + 2)-th and (a + 3)-th samplings is obtained and returned, and then it is determined whether the operating states of the power supply device are the same until the difference between the output currents of the (a + n)-th and (a + n + 1)-th samplings is greater than the set current threshold, then the loop is determined to end, and step S0224 is entered: obtain the current count value X. At this time, n loops have been experienced, so the current count value X = x + n. If the operating state of the power supply device obtained at the (a + 1)-th time is state one, then the duration of state one is the product X*m of X and the preset time interval m. If the operating state of the power supply device obtained at the (a + 1)-th time is state two, then the duration of state two is the product X*m of X and the preset time interval m.

[0108] In some embodiments, two count values p and q can be set to record the durations of state one and state two respectively.

[0109] Through the above method, the Figure 6 duration T1 of state one and duration T2 of state two shown in

[0110] can be obtained. Figure 6 The following is an illustration of the specific execution manner of the above step S03:

[0111] As Figure 6 shown, assume that the current operating state is state one and is within the Y1 - X2 interval. According to step S02, the predicted first switching moment is located at X2. Then step S03 will determine the first instruction moment Z1 in advance of the predicted first switching moment X2. As Figure 6 shown, the first instruction moment Z1 and the predicted first switching moment X2 differ by a first time t1.

[0112] Similarly, if the current operating state is state two and is within the X2 - Y2 interval, then according to step S02, the predicted second switching moment is located at Y2. Then step S03 will determine the second instruction moment Z2 in advance of the predicted second switching moment Y2. As Figure 6 shown, the second instruction moment Z2 and the predicted second switching moment Y2 differ by a second time t2.

[0113] In some embodiments, t1 and t2 are of the same magnitude.

[0114] In some embodiments, t1 and t2 can be preset fixed values.

[0115] At the first instruction moment Z1 and the second instruction moment Z2, the control unit will correspondingly issue corresponding instructions to adjust the output voltage of the power supply device. By setting the first instruction moment Z1 and the second instruction moment Z2 respectively before the corresponding predicted first switching moment X2 and the predicted second switching moment Y2, the initiative of the power supply device to cope with sudden changes in the output voltage can be further improved, thereby improving the dynamic performance of the power supply device and controlling and reducing the fluctuation range of the output voltage of the power supply device.

[0116] After determining the first instruction moment Z1 or the second instruction moment Z2, it is also necessary to continuously judge whether the current moment within the period reaches the first instruction moment Z1. Specifically, it includes:

[0117] If the working state at the current moment is State 1, then as Figure 5A shown, execute the following steps:

[0118] S031: Obtain the current moment of the current working state;

[0119] S032: Judge the magnitude relationship between the current moment and the first instruction moment Z1;

[0120] S033: If the current moment is less than or equal to the first instruction moment Z1, return to step S031; if the current moment is greater than the first instruction moment Z1, the control unit issues the corresponding instruction.

[0121] If the working state at the current moment is State 2, then as Figure 5B shown, execute the following steps:

[0122] S131: Obtain the current moment of the current working state;

[0123] S132: Judge the magnitude relationship between the current moment and the second instruction moment Z2;

[0124] S133: If the current moment is less than or equal to the second instruction moment Z2, return to step S131; if the current moment is greater than the second instruction moment Z2, the control unit issues the corresponding instruction.

[0125] Referring to Figure 6 , if the current working state is State 1 and within the Y1-X2 interval, it is necessary to judge the magnitude relationship between the current moment and the first instruction moment Z1. If the current moment is less than or equal to the first moment Z1, return to re-obtain the real-time updated current moment. If the current moment is greater than the first instruction moment Z1, it means that the control unit needs to issue the corresponding instruction; then it is necessary to judge the magnitude relationship between the current moment and the second instruction moment Z2. If the current moment is less than or equal to the first moment Z1, return to re-obtain the real-time updated current moment. If the current moment is greater than the first instruction moment Z2, it means that the control unit needs to issue the corresponding instruction.

[0126] In some other embodiments, the comparison of time instants can also be directly made using the magnitude of the count value x. The product of the count value x and the same preset time interval m is the duration of the working state. Since the count value x is updated in real time, the real-time value of the count value x can also be used as a reference factor for judging the time instant.

[0127] Reference Figure 6 , if the working state at the current time instant is State One and it is within the interval Y1 - X2, assuming that the time measurement of State One within the first period 0 - X1 using the count value x gives the magnitude of T1 as K, then at the current time instant, the predicted first switching time instant converted to the count value x is K, and subtracting a first time t1 gives the first instruction time instant Z1. At this time, t1 can also be expressed in the unit of the count value x. For example, if the count value equivalent to the first time t1 is set to 5, then when the first instruction time instant Z1 is converted to the unit of the count value x, its magnitude is (K - 5); then the current count value X at the current time instant is compared with the magnitude of (K - 5) in a loop. If the current count value X is less than (K - 5), the count value x continues to accumulate. As the number of loop iterations increases, when the control unit determines that the current count value X is greater than (K - 5), the control unit issues a corresponding instruction to actively increase the output voltage. Similarly, the method when the working state at the current time instant is State Two is similar to that of State One and will not be elaborated here.

[0128] Please continue to refer to Figure 6 to illustrate the specific control methods of the control unit at the first instruction time instant Z1 and the second instruction time instant Z2.

[0129] At the first instruction time instant Z1, the control unit will control to increase the output voltage of the power supply device, such as increasing the output voltage of the power supply device to the sum of the preset target voltage value Vo and the first gain;

[0130] At the second instruction time instant Z2, the control unit will control to decrease the output voltage of the power supply device, such as decreasing the output voltage of the power supply device to the difference between the preset target voltage value Vo and the second gain.

[0131] Reference Figure 6, the output voltage in the 0 - Y1 interval is the output voltage when the control method disclosed in the present invention is not used. As can be seen from the PWM waveform, its control action starts only after the working state switches. For example, in frequency modulation control, the maximum value of the output voltage is Vmax and the minimum value is Vmin. In the Y1 - Y2 interval, using the control method disclosed in the present invention, as can be seen from the PWM waveform, before the working state switches, active control has been intervened at the first instruction time Z1 and the second instruction time Z2, such as frequency modulation control. Of course, it can also be duty cycle modulation. The present invention does not limit this. By intervening in active control in advance, the voltage fluctuation amplitude is only (V1 - V2). Compared with (Vmax - Vmin), the voltage fluctuation range is significantly reduced, effectively increasing the dynamic performance of the power supply device.

[0132] In some embodiments, both the first gain and the second gain are fixed values;

[0133] In some embodiments, both the first gain and the second gain are set multiples of the difference between the maximum output voltage and the minimum output voltage of the power supply device. For example, it is 30% of (Vmax - Vmin).

[0134] In some embodiments, the output current of the power supply device is direct current. The power supply device includes but is not limited to DCDC converters, ACDC converters, and the topological structure of the power supply device includes but is not limited to LLC architectures.

[0135] It should be noted that since the control method disclosed in the present invention needs to utilize relevant parameters of the previous cycle, such as the duration of the state, in the first cycle after the power supply device starts up, the empty - built - in method of the present invention cannot be immediately intervened, as Figure 6 shown in the 0 - Y1 interval in

[0136] It should be noted that after the power supply device has been working for some time, the state of the load further changes. For example, the power demand of the load becomes larger, the original heavy load becomes a light load, and a heavy load state with a larger power demand is added. This control method is still applicable. In this state, the changed heavy load can be regarded as state one, and the heavy load with a larger power demand can be regarded as state two, which can be matched with this control method.

[0137] The control method disclosed in the present invention makes predictions and corresponding active controls in the current cycle based on the state of the previous cycle. Therefore, this method can be used for various loads with periodic changes in power demand and has wide applicability. After applying this control method, the circuit response time of the power supply device is greatly shortened, approaching zero. And even if the period of the power demand of the load itself changes, it can be adaptively adjusted, and full - digital control of the power supply device can be achieved, greatly improving the working performance of the power supply device.

[0138] Other embodiments of the present application will be readily apparent to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only illustrative, and the true scope and spirit of the present application are pointed out by the following claims.

[0139] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A control method for a power supply device, characterized in that: A power supply device is provided, and the power supply device includes a control unit; The operating states of the power supply device include continuously switching State 1 and State 2; Adjacent State 1 and State 2 form a cycle. In each cycle, State 1 switches to State 2 in the current cycle at the first switching moment; in each cycle, State 2 switches to State 1 in the next cycle at the second switching moment; The control method includes the following steps: Obtain the current operating state of the power supply device; Predict the switching moment from the current operating state to the next different operating state according to the current operating state of the power supply device; The control unit issues an instruction earlier than the predicted next switching moment, and the instruction is used to adjust the output voltage of the power supply device.

2. The control method for a power supply device according to claim 1, characterized in that: The step of predicting the corresponding next switching moment according to the current operating state of the power supply device includes: Obtain the starting moment of the current operating state; Obtain the duration of the operating state that is the same as the current operating state in the previous cycle of the power supply device; The corresponding next switching moment predicted by the current operating state is the sum of the starting moment of the current operating state and the duration of the operating state that is the same as the current operating state in the previous cycle.

3. The control method for a power supply device according to claim 2, characterized in that: The obtaining of the starting moment of the current operating state includes: If the current operating state is State 1, the starting moment of the current operating state is the second switching moment in the previous cycle; If the current operating state is State 2, the starting moment of the current operating state is the first switching moment in the current cycle.

4. The control method for a power supply device according to claim 2, characterized in that: The steps of obtaining the duration of State 1 and the duration of State 2 include: The control unit obtains the operating state of the power supply device multiple times at a preset time interval; The control unit judges whether the operating states of the power supply device at the a-th time and the (a + 1)-th time are the same; If the operating states of the power supply device at the a-th time and the (a + 1)-th time are different, start a counting loop, and the count value is x, where x ≥ 0, and the initial value of the count value x is 0; Loop and execute the following steps until it is judged that the operating states of the power supply device in two adjacent times are different, then end the loop and obtain the current count value X, where X = x + n, and n is the number of times of loop execution: Obtain the operating states of the power supply device in two adjacent times; Judge whether the operating states of the power supply device in two adjacent times are the same; If the operating states of the power supply device in two adjacent times are the same, the count value x is incremented, and return to obtain the operating states of the power supply device in two adjacent times again; If the operating state of the power supply device obtained at the (a + 1)-th time is State 1, the duration of State 1 is equal to the product of the current count value X and the preset time interval; if the operating state of the power supply device obtained at the (a + 1)-th time is State 2, the duration of State 2 is equal to the product of the current count value X and the preset time interval.

5. The control method of the power supply device according to claim 1, characterized in that the step that the control unit issues an instruction earlier than the predicted next switching moment includes: if the current working state is state one, the control unit issues the instruction at the first instruction moment, and the first instruction moment is the predicted first switching moment minus the first time; if the current working state is state two, the control unit issues the instruction at the second instruction moment, and the second instruction moment is the predicted second switching moment minus the second time.

6. The control method of the power supply device according to claim 5, characterized in that both the first time and the second time are fixed values.

7. The control method of the power supply device according to claim 5, characterized in that the step that the control unit issues the instruction at the first instruction moment includes: obtain the current moment of the current working state; judge the magnitude relationship between the current moment and the first instruction moment; if the current moment is less than or equal to the first instruction moment, return to re-obtain the current moment of the current working state; if the current moment is greater than the first instruction moment, the control unit issues the instruction; the step that the control unit issues the second instruction at the second instruction moment includes: obtain the current moment of the current working state; judge the magnitude relationship between the current moment and the second instruction moment; if the current moment is less than or equal to the second instruction moment, return to re-obtain the current moment of the current working state; if the current moment is greater than the second instruction moment, the control unit issues the instruction.

8. The control method of the power supply device according to any one of claims 1-7, characterized in that the absolute value of the difference between the output current when the power supply device works in state one and the output current when the power supply device works in state two is greater than a preset current threshold.

9. The control method of the power supply device according to claim 8, characterized in that the output current when the power supply device works in state one is less than the output current when the power supply device works in state two.

10. The control method of the power supply device according to claim 9, characterized in that if the current working state of the power supply device is state one, the instruction is used to increase the output voltage of the power supply device; if the current working state of the power supply device is state two, the instruction is used to decrease the output voltage of the power supply device.

11. The control method of the power supply device according to claim 10, characterized in that obtain a preset target voltage value included in the power supply device; if the current working state of the power supply device is state one, the instruction is used to make the output voltage of the power supply device equal to the sum of the preset target voltage value and a first gain; if the current working state of the power supply device is state two, the instruction is used to make the output voltage of the power supply device equal to the difference between the preset target voltage value and a second gain.

12. The control method of the power supply device according to claim 11, characterized in that both the first gain and the second gain are fixed values.

13. The control method of the power supply device according to claim 11, characterized in that The first gain and the second gain are both set multiples of the difference between the maximum output voltage and the minimum output voltage of the power supply device.

14. The power supply device control method according to any one of claims 1-7, characterized in that, The output current of the power supply device is direct current.

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