Reverse current control method and device for phase-shifted full-bridge circuit

Abstract

The application provides a reverse current control method and device of a phase-shifted full-bridge circuit, and relates to the field of power electronics. The method comprises the following steps: determining an error value of a reverse input current according to a sampling value of the reverse input current of the phase-shifted full-bridge circuit and a reference value of the reverse input current; determining a compensation control amount of a switch driving signal of the phase-shifted full-bridge circuit according to the error value; determining a period control amount and a duty cycle control amount of the switch driving signal according to the compensation control amount; and controlling the switch driving signal according to the period control amount and the duty cycle control amount. The method can realize the control of a wide range of input currents.

Description

Technical Field

[0001] This application relates to the field of power electronics, and more specifically, to a method and apparatus for reverse current control of a phase-shifted full-bridge circuit. Background Technology

[0002] Charging and discharging batteries is a common application scenario, but excessive input current inevitably affects battery production safety and lifespan. Therefore, current control during battery charging and discharging can effectively improve production safety and extend battery life. However, existing current control methods cannot effectively control a wide range of input currents, potentially impacting battery production safety and lifespan. Therefore, providing an effective current control solution has become an urgent problem to be solved. Summary of the Invention

[0003] This application provides a reverse current control method and device for a phase-shifted full-bridge circuit, which can effectively control the input current over a wide range.

[0004] This application provides a method for reverse current control of a phase-shifted full-bridge circuit. The method includes: determining an error value of the reverse input current based on a sampled value of the reverse input current of the phase-shifted full-bridge circuit and a reference value of the reverse input current; determining a first compensation control quantity of a switching drive signal of the phase-shifted full-bridge circuit based on the error value, wherein the first compensation control quantity is a compensation amount for the error value and is a control quantity corresponding to the period or duty cycle of the switching drive signal; determining a period control quantity and a duty cycle control quantity of the switching drive signal based on the first compensation control quantity, wherein the period control quantity is within the range of the period of the switching drive signal and the duty cycle control quantity is within the range of the duty cycle of the switching drive signal; and controlling the switching drive signal based on the period control quantity and the duty cycle control quantity.

[0005] In the embodiments of this application, after obtaining the compensation control quantity based on the sampled value and reference value of the reverse input current of the phase-shifted full-bridge circuit, the period control quantity and duty cycle control quantity used to control the switch drive signal are determined based on the compensation control quantity. In this way, the period and duty cycle of the switch drive signal are adjustable, thereby significantly widening the control range of the input current.

[0006] In some possible embodiments, determining the period control amount and duty cycle control amount of the switch drive signal based on the first compensation control amount includes: when the first compensation control amount satisfies the range of the period of the switch drive signal, determining the period control amount as the first compensation control amount and the duty cycle control amount as the first predetermined value.

[0007] In this embodiment, the duty cycle control quantity is a first predetermined value, the period control quantity is equal to the compensation control quantity, and the period control quantity is exactly within the range of period control quantities required for normal circuit operation.

[0008] In some possible embodiments, determining the period control amount and duty cycle control amount of the switch drive signal based on the first compensation control amount includes: when the first compensation control amount is less than the lower limit of the range of the period of the switch drive signal, determining the period control amount as the lower limit of the range of the period of the switch drive signal, and the duty cycle control amount as the first predetermined value.

[0009] In this embodiment, the duty cycle control quantity is a first predetermined value, the period control quantity is equal to the lower limit of the period value range, and the period control quantity is the minimum period control quantity required for the normal operation of the circuit, so that the circuit can operate normally.

[0010] In some possible embodiments, determining the period control amount and duty cycle control amount of the switch drive signal based on the first compensation control amount includes: when the first compensation control amount is greater than the upper limit of the range of the period of the switch drive signal, converting the first compensation control amount into a second compensation control amount, wherein the second compensation control amount is the control amount corresponding to the duty cycle of the switch drive signal; and determining the period control amount and the duty cycle control amount based on the second compensation control amount.

[0011] In this embodiment, the second compensation control quantity refers to the control quantity corresponding to the duty cycle of the switch drive signal that can compensate for the error value. By controlling the switch drive signal through the duty cycle control quantity, control of the input current, especially large current, can be achieved.

[0012] In some possible embodiments, determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: determining the duty cycle control quantity as the second compensation control quantity when the second compensation control quantity satisfies the value range of the duty cycle of the switch drive signal, and the period control quantity as the upper limit of the value range of the period of the switch drive signal.

[0013] In this embodiment, the duty cycle control amount is equal to the second compensation control amount, and the duty cycle control amount is exactly within the range of the duty cycle control amount required for normal circuit operation.

[0014] In some possible embodiments, determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: when the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal, determining the duty cycle control quantity as the lower limit of the duty cycle range of the switch drive signal, and the period control quantity as the upper limit of the period range of the switch drive signal.

[0015] In this embodiment, the duty cycle control quantity is equal to the lower limit of the duty cycle range. The duty cycle control quantity is at the minimum duty cycle control quantity required for the circuit to operate normally, which enables the circuit to operate normally.

[0016] In some possible embodiments, determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: when the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal, determining the duty cycle control quantity as the upper limit of the duty cycle range of the switch drive signal, and the period control quantity as the upper limit of the period range of the switch drive signal.

[0017] In this embodiment, the duty cycle control quantity is equal to the upper limit of the duty cycle range. The duty cycle control quantity is at the maximum duty cycle control quantity required for the circuit to operate normally, which enables the circuit to operate normally.

[0018] A second aspect of this application provides a reverse current control device for a phase-shifted full-bridge circuit. The device includes: an acquisition module for acquiring a sampled value of the reverse input current of the phase-shifted full-bridge circuit and acquiring a reference value of the reverse input current; a processing module for determining an error value of the reverse input current based on the sampled value and the reference value; determining a first compensation control quantity for a switching drive signal of the phase-shifted full-bridge circuit based on the error value, wherein the first compensation control quantity is a control quantity corresponding to the period or duty cycle of the switching drive signal capable of compensating for the error value; determining a period control quantity and a duty cycle control quantity for the switching drive signal based on the first compensation control quantity, wherein the period control quantity is within the range of the period of the switching drive signal and the duty cycle control quantity is within the range of the duty cycle of the switching drive signal; and a control module for controlling the switching drive signal based on the period control quantity and the duty cycle control quantity.

[0019] In this embodiment, after the processing module determines the compensation control amount based on the sampled and reference values ​​of the reverse input current of the phase-shifted full-bridge circuit obtained by the acquisition module, the processing module then determines the period control amount and duty cycle control amount for controlling the switch drive signal based on the compensation control amount. In this way, the period and duty cycle of the switch drive signal are adjustable, thereby significantly widening the control range of the input current.

[0020] In some possible embodiments, the processing module is configured to determine the period control quantity as the first compensation control quantity and the duty cycle control quantity as the first predetermined value, provided that the first compensation control quantity is within the range of the period of the switch drive signal.

[0021] In some possible embodiments, the processing module is configured to determine that the period control quantity is the lower limit of the period range of the switch drive signal, and the duty cycle control quantity is the first predetermined value, when the first compensation control quantity is less than the lower limit of the period range of the switch drive signal.

[0022] In some possible embodiments, the processing module is configured to convert the first compensation control quantity into a second compensation control quantity when the first compensation control quantity is greater than the upper limit of the range of the period of the switch drive signal, wherein the second compensation control quantity is the control quantity corresponding to the duty cycle of the switch drive signal; and determine the period control quantity and the duty cycle control quantity based on the second compensation control quantity.

[0023] In some possible embodiments, the processing module is used to determine the duty cycle control quantity as the second compensation control quantity when the second compensation control quantity is within the range of the duty cycle of the switch drive signal, and the period control quantity is the upper limit of the range of the period of the switch drive signal.

[0024] In some possible embodiments, the processing module is configured to determine that the duty cycle control quantity is the lower limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal, when the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal.

[0025] In some possible embodiments, the processing module is configured to determine that the duty cycle control quantity is the upper limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal, when the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal.

[0026] A third aspect of this application provides a reverse current control device for a phase-shifted full-bridge circuit, including a memory and a processor. The memory is used to store instructions, and the processor is used to read the instructions and execute the methods of the first aspect and any possible implementation thereof based on the instructions.

[0027] The fourth aspect of this application provides a phase-shifted full-bridge circuit, including the reverse current control device of the phase-shifted full-bridge circuit of the second or third aspect described above.

[0028] The fifth aspect of this application provides a readable storage medium for storing a computer program for performing the methods of the first aspect and any possible implementation thereof. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the drawings without creative effort.

[0030] Figure 1 This is a schematic diagram illustrating an application scenario of the reverse current control method for a phase-shifted full-bridge circuit disclosed in an embodiment of this application;

[0031] Figure 2 This is an architectural diagram of the reverse current control method for a phase-shifted full-bridge circuit disclosed in an embodiment of this application;

[0032] Figure 3 This is a schematic flowchart of a reverse current control method for a phase-shifted full-bridge circuit disclosed in an embodiment of this application;

[0033] Figure 4 This is a schematic flowchart of a reverse current control method for a phase-shifted full-bridge circuit disclosed in an embodiment of this application;

[0034] Figure 5 This is a schematic block diagram of a reverse current control device for a phase-shifted full-bridge circuit disclosed in another embodiment of this application. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0036] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used in the description of this application is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms "comprising" and "having," and any variations thereof, in the description, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the description, claims, or accompanying drawings of this application are used to distinguish different objects, not to describe a specific order or hierarchy.

[0037] In this application, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this application can be combined with other embodiments.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," "attachment," and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0039] In this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this application, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0040] In this application, "multiple" refers to two or more (including two), and similarly, "multiple groups" refers to two or more (including two), and "multiple pieces" refers to two or more (including two).

[0041] Existing current control methods for phase-shifted full-bridge circuits primarily achieve positive control of the circuit current by adjusting the circuit's duty cycle. When the switching period is fixed, controlling the input current solely by adjusting the duty cycle cannot achieve a wide range of current control.

[0042] In view of this, embodiments of this application provide a reverse current control scheme for a phase-shifted full-bridge circuit, which achieves current control over a wide range based on the periodic control amount and duty cycle control amount of the control switch drive signal.

[0043] This application provides an effective reverse current control method for a phase-shifted full-bridge circuit, which can be applied to various devices involving battery charging and discharging.

[0044] A phase-shifted full-bridge refers to a full-bridge topology that features soft switching during forward operation. It utilizes phase-shift control and a resonant inductor between the two arms of the primary-side full-bridge to achieve zero-voltage soft switching of the primary-side full-bridge switches.

[0045] Reverse current control refers to controlling the input current when it is input from the secondary rectifier bridge side.

[0046] The period refers to the time interval between two adjacent pulses in a periodically repeating pulse sequence.

[0047] Duty cycle refers to the percentage of time a switch is on in a circuit during the entire circuit's operating cycle. Duty cycle control is achieved by modulating the pulse width of a voltage signal of a certain frequency applied to the switch using an electronic control unit, thus enabling precise and continuous control of the component's operating status.

[0048] Periodic control quantity refers to the control quantity of the switching frequency in the control circuit.

[0049] Duty cycle control refers to the percentage of time the secondary switch is on during the entire circuit's operating cycle.

[0050] The switch drive signal refers to the signal that drives each switch in the phase-shifted full-bridge circuit to turn on or off. The switch drive signal can be a pulse signal, but this embodiment is not limited to this.

[0051] The compensation control quantity refers to the value obtained by the compensator in compensating for the current error value. The compensator may include a PI controller, Venable controller, PR controller, PID controller, etc., and this application embodiment is not limited to this. Because the compensator gradually adjusts its output compensation control quantity through the principle of closed-loop negative feedback, the input error value becomes smaller and smaller. In this process, the compensation control quantity output by the compensator is gradually converging towards the point where the input error value approaches zero. Due to the characteristics of the DC source input current on the secondary side of the phase-shifted full-bridge circuit, in order to ensure that the current error value adjusted by the compensator returns to zero, the compensation control quantity output by the compensator may exceed the range of the period / duty cycle value after final convergence.

[0052] Furthermore, fluctuations in the input voltage or changes in the current reference value may cause fluctuations in the current error value, which in turn may cause fluctuations in the compensation control quantity, resulting in the compensation control quantity exceeding the range of the period / duty cycle. If the period control quantity or duty cycle control quantity is directly used as the compensation control quantity in this case, it may cause circuit malfunction and damage. Therefore, when the compensation control quantity exceeds the range of the period / duty cycle of the switch drive signal, the period control quantity should be taken from the extreme value within the period range of the switch drive signal, and the duty cycle control quantity should be taken from the extreme value within the duty cycle range of the switch drive signal. This protects the circuit from malfunction and allows for control of a wide range of currents.

[0053] For ease of explanation, the following embodiments use a phase-shifted full-bridge circuit according to an embodiment of this application as an example.

[0054] Figure 1 This is a schematic diagram illustrating an application scenario of the technical solution in an embodiment of this application. For example... Figure 1 As shown, the phase-shifted full-bridge circuit includes a primary-side full-bridge, a resonant inductor Lr, a transformer M, a secondary-side rectifier bridge, and an output inductor Lo. The left side of transformer M forms the primary-side full-bridge, and the right side forms the secondary-side rectifier bridge. The primary-side full-bridge circuit may include multiple switches G1-G4, and the secondary-side rectifier bridge may include multiple switches G5-G6. The phase-shifted full-bridge circuit may include at least one output inductor Lo, for example, as... Figure 1 The circuit structure shown includes two output inductors, Lo1 and Lo2. When current is input from the secondary side DC source Vin, its input current has the following characteristics:

[0055] When duty cycle At that time, the input current satisfies:

[0056]

[0057] When duty cycle At that time, the input current satisfies:

[0058]

[0059] Where Vin refers to the input DC source voltage, Vout refers to the output DC source voltage, n refers to the turns ratio from the primary side to the secondary side of the transformer, Lr refers to the resonant inductance, Lm refers to the magnetizing inductance of the transformer referred to the primary side, D refers to the duty cycle, and T refers to the switching period.

[0060] In one implementation, when the duty cycle D is less than the critical duty cycle, the input current can be controlled by adjusting the switching period T. When the duty cycle D is greater than the critical duty cycle, the switching period T can be fixed at its maximum value, and the input current can be controlled by adjusting the duty cycle D to achieve a wide range of current control.

[0061] Figure 2 The architecture of a reverse current control method for a phase-shifted full-bridge circuit according to an embodiment of this application is shown. The input current on the secondary rectifier bridge side is acquired by a sampling circuit, and the current sampling value and current reference value are processed by a processing module to output a period / duty cycle control quantity to control the switching drive signal.

[0062] Figure 3 This is a schematic flowchart of a reverse current control method for a phase-shifted full-bridge circuit disclosed in an embodiment of this application.

[0063] Step 301: Determine the error value of the reverse input current based on the sampled value of the reverse input current and the reference value of the reverse input current of the phase-shifted full-bridge circuit.

[0064] Reverse input current refers to the DC source input current on the secondary side.

[0065] The sampled value refers to the sampled current value in the phase-shifted full-bridge circuit. For example, such as... Figure 2 As shown, this sampled value can be obtained using a sampling circuit.

[0066] The reference value refers to the expected current value in a phase-shifted full-bridge circuit.

[0067] The error value refers to the amount of error between the sampled value of the reverse input current and the reference value of the reverse input current in a phase-shifted full-bridge circuit.

[0068] Step 302: Based on the error value, determine the first compensation control quantity of the switching drive signal of the phase-shifted full-bridge circuit, wherein the first compensation control quantity is the compensation quantity of the error value, the first compensation control quantity is the control quantity corresponding to the period or duty cycle of the switching drive signal, and the first compensation control quantity is the control quantity corresponding to the period or duty cycle of the switching drive signal that can compensate for the error value.

[0069] For example, the first compensation control quantity can be determined by a compensator. The compensator may include a PI controller, a Venable controller, a PR controller, a PID controller, etc., and this embodiment is not limited to this.

[0070] Step 303: Based on the first compensation control quantity, determine the period control quantity and duty cycle control quantity of the switch drive signal, wherein the period control quantity is within the range of the period of the switch drive signal, and the duty cycle control quantity is within the range of the duty cycle of the switch drive signal.

[0071] The range of the period value is related to the specific circuit parameter design. The range of the period value may include the upper and lower limits of the switching frequency used, a preset range, a modifiable range, etc., but this embodiment does not limit it.

[0072] The duty cycle range refers to the percentage of the time the control circuit is on during the entire circuit's operating cycle. The duty cycle range can include a preset range, a modifiable range, etc., and this embodiment does not limit this. The upper limit of the duty cycle range can be determined based on the current value required by the circuit, or it can be a preset upper limit, etc., and this embodiment does not limit this. The lower limit of the duty cycle range can be a preset lower limit, a lower limit determined based on a functional relationship, etc., and this embodiment does not limit this.

[0073] Step 304: Control the switch drive signal according to the period control quantity and the duty cycle control quantity.

[0074] For example, a PWM controller can be used to control the switch drive signal based on the aforementioned periodic control and duty cycle control values.

[0075] In the embodiments of this application, after obtaining the compensation control quantity based on the sampled value and reference value of the reverse input current of the phase-shifted full-bridge circuit, the period control quantity and duty cycle control quantity used to control the switch drive signal are determined based on the compensation control quantity. In this way, the period and duty cycle of the switch drive signal are adjustable, thereby significantly widening the control range of the input current.

[0076] Figure 4 This is a schematic flowchart of the reverse current control method for the phase-shifted full-bridge circuit disclosed in this application. Steps similar to those in the previous embodiments can be referred to the previous embodiments, and for the sake of brevity, will not be repeated here.

[0077] Step 401: Enter control interrupt.

[0078] A control interrupt refers to a situation where the system can automatically enter a control interrupt routine at regular intervals or based on a trigger signal. The current control method in this embodiment begins execution after entering a control interrupt.

[0079] Step 402: Determine the error value of the reverse input current based on the sampled value of the reverse input current and the reference value of the reverse input current of the phase-shifted full-bridge circuit.

[0080] Step 403: Determine the first compensation control quantity of the switching drive signal of the phase-shifted full-bridge circuit based on the error value.

[0081] In some embodiments of this application, optionally, the first compensation control quantity is a control quantity corresponding to the period of the switching drive signal that can compensate for the error value when the duty cycle control quantity takes a first predetermined value. The first compensation control quantity may include the value obtained after compensating the current error value through a compensator, and this embodiment is not limited to this. The first predetermined value refers to a preset value of the duty cycle control quantity within the range of the duty cycle. The first predetermined value may include the upper limit, lower limit, or any preset value within the range of the duty cycle, etc., and this embodiment is not limited to this. Optionally, for the case of small current, the first predetermined value may be the lower limit of the duty cycle.

[0082] In the embodiments of this application, when the duty cycle control amount is a first predetermined value, the period control amount and duty cycle control amount of the switch drive signal are determined according to the first compensation control amount, so that the period of the switch drive signal can be adjusted under a fixed duty cycle to achieve control of small current.

[0083] Step 404: Determine whether the first compensation control quantity exceeds the period range of the switch drive signal.

[0084] In one embodiment of this application, optionally, in step 405, if the first compensation control quantity is within the range of the period of the switch drive signal, the period control quantity is determined as the first compensation control quantity. Then, step 407 is executed, where the duty cycle control quantity is taken as a first predetermined value, and the switch drive signal is controlled according to the period control quantity.

[0085] The first compensation control quantity being within the range of the switching drive signal period means that the first compensation control quantity is within the upper and lower limits of the switching drive signal period. In other words, the first compensator control quantity is lower than the upper limit of the period and higher than the lower limit of the period.

[0086] In the embodiments of this application, when the first compensation control quantity is within the range of the switching drive signal period, the first compensation control quantity is taken as the periodic control quantity, and the periodic control quantity is exactly within the range of the periodic control quantity required for the normal operation of the circuit.

[0087] In one embodiment of this application, optionally, in step 406, if the first compensation control amount is less than the lower limit of the value range of the period of the switch drive signal, the period control amount is determined to be the lower limit of the value range of the period of the switch drive signal. Then, step 407 is executed, the duty cycle control amount is taken as a first predetermined value, and the switch drive signal is controlled according to the period control amount.

[0088] The lower limit of the period range refers to the lowest value within the period range. It may include the upper limit of the circuit switching frequency, a preset lower limit of the period, etc., but this embodiment does not limit it.

[0089] In the embodiments of this application, when the first compensation control quantity is less than the lower limit of the period's value range, if the first compensation control quantity is taken as the period control quantity, it may cause the period control quantity to be less than the minimum period control quantity required for the circuit to operate normally, thereby causing the circuit to malfunction. Therefore, when the first compensation control quantity is less than the lower limit of the period's value range, the period control quantity is equal to the lower limit of the period's value range, which allows the circuit to operate normally.

[0090] In one embodiment of this application, optionally, in step 408, if the first compensation control quantity is greater than the upper limit of the range of the period of the switch drive signal, the first compensation control quantity is converted into a second compensation control quantity. In this case, the period control quantity and the duty cycle control quantity are then determined based on the second compensation quantity.

[0091] The second compensation control quantity refers to the control quantity corresponding to the duty cycle of the switch drive signal that can compensate for the error value. The second compensation control quantity can be determined based on the first compensation control quantity, and the determination method may include multiplying the first compensation control quantity by a specific coefficient, etc., which is not limited in this embodiment. The specific coefficient may include preset coefficient values, coefficient values ​​determined by functional relationships, coefficient values ​​determined by looking up a table, etc., which is not limited in this embodiment.

[0092] The upper limit of the period range refers to the maximum value within the period range. This may include the lower limit of the switching frequency, a preset upper limit of the period, etc., but this embodiment does not limit this.

[0093] In the embodiments of this application, the circuit can control the switch drive signal through the duty cycle control quantity. When the current output of the circuit needs to increase, the duty cycle control quantity can be adjusted to control the switch drive signal by using a fixed period as the upper limit of the period, while avoiding reducing switching losses.

[0094] Step 409: Determine whether the second compensation control quantity exceeds the duty cycle range of the switch drive signal.

[0095] In one embodiment of this application, optionally, in step 410, if the second compensation control quantity is within the range of the duty cycle of the switch drive signal, the duty cycle control quantity is determined as the second compensation control quantity. Then, step 413 is executed, where the period control quantity is taken as the upper limit of the period, and the switch drive signal is controlled according to the duty cycle control quantity.

[0096] The second compensation control quantity being within the range of the duty cycle of the switch drive signal means that the second compensation control quantity is within the upper and lower limits of the duty cycle of the switch drive signal. In other words, the second compensator control quantity is lower than the upper limit of the duty cycle and higher than the lower limit of the duty cycle.

[0097] In the embodiments of this application, when the second compensation control quantity is within the range of the duty cycle of the switch drive signal, the second compensation control quantity is taken as the duty cycle control quantity, and the duty cycle control quantity is exactly within the range of the duty cycle control quantity required for the normal operation of the circuit.

[0098] In one embodiment of this application, optionally, in step 411, if the second compensation control amount is greater than the upper limit of the duty cycle range of the switch drive signal, the duty cycle control amount is determined to be the upper limit of the duty cycle range of the switch drive signal. Then, step 413 is executed, where the period control amount is taken as the upper limit of the period, and the switch drive signal is controlled according to the duty cycle control amount.

[0099] In the embodiments of this application, due to the characteristics of the aforementioned compensation control quantity, there may be a situation where the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal. If the second compensation control quantity is taken as the duty cycle control quantity in this case, it may result in the duty cycle control quantity exceeding the maximum duty cycle control quantity required for normal circuit operation, thereby causing a circuit malfunction. Therefore, when the second compensation control quantity is greater than the upper limit of the duty cycle range, taking the upper limit of the duty cycle range for the duty cycle control quantity allows the circuit to operate normally.

[0100] In one embodiment of this application, optionally, in step 412, if the second compensation control amount is less than the lower limit of the duty cycle range of the switch drive signal, the duty cycle control amount is determined to be the lower limit of the duty cycle range of the switch drive signal. Then, step 413 is executed, where the period control amount is taken as the upper limit of the period, and the switch drive signal is controlled according to the duty cycle control amount.

[0101] The second compensation control quantity being less than the lower limit of the duty cycle range of the switch drive signal means that, due to the characteristics of the aforementioned first compensation control quantity, the second compensation control quantity determined by the first compensation control quantity may exceed the duty cycle range after final convergence. Therefore, the second compensation control quantity may be less than the lower limit of the duty cycle range of the switch drive signal or greater than the upper limit of the duty cycle range of the switch drive signal.

[0102] In the embodiments of this application, due to the characteristics of the aforementioned compensation control quantity, the second compensation control quantity may be less than the lower limit of the duty cycle range of the switch drive signal. When the second compensation control quantity is less than the lower limit of the duty cycle range, if the second compensation control quantity is taken as the duty cycle control quantity, it may result in the duty cycle control quantity being less than the minimum duty cycle control quantity required for normal circuit operation, thereby causing circuit failure. Therefore, when the second compensation control quantity is less than the lower limit of the duty cycle range, taking the lower limit of the duty cycle range as the duty cycle control quantity allows the circuit to operate normally.

[0103] In the foregoing embodiments, the first compensation control quantity is the control quantity corresponding to the period of the switch drive signal that can compensate for the error value when the duty cycle control quantity takes a first predetermined value. Those skilled in the art will understand that the period and duty cycle can also be interchanged; that is, the first compensation control quantity can also be the control quantity corresponding to the duty cycle of the switch drive signal that can compensate for the error value when the period control quantity takes a second predetermined value. The period and duty cycle are interchanged accordingly in subsequent processing, and for simplicity, this will not be elaborated further here.

[0104] The reverse current control method of the phase-shifted full-bridge circuit according to the embodiments of this application has been described above. The reverse current control device of the phase-shifted full-bridge circuit according to the embodiments of this application is described below. For parts not described in detail, please refer to the foregoing embodiments.

[0105] Figure 5 This is a schematic block diagram of a reverse current control device for a phase-shifted full-bridge circuit disclosed in another embodiment of this application. In the embodiments of this application, the reverse current control device for the phase-shifted full-bridge circuit may include an acquisition module 501, a processing module 502, and a control module 503.

[0106] The acquisition module 501 can be used to acquire the sampled value of the reverse input current and the reference value of the reverse input current of the phase-shifted full-bridge circuit.

[0107] The acquisition module 501 can also be used to acquire the sampled value of the reverse input current, which means that the acquisition module 501 acquires the input current on the secondary rectifier bridge side. The acquisition module 501 can also be used to acquire the sampled value of the reverse input current, the reference value of the reverse input current, the sampled value of the forward input current, the sampled and reference values ​​of the voltage, etc., including the phase-shifted full-bridge circuit, but this embodiment is not limited to these.

[0108] The processing module 502 can be used to determine the error value of the reverse input current based on the sampled value and the reference value of the reverse input current. Based on the error value of the reverse input current, it determines the first compensation control quantity of the switching drive signal for the phase-shifted full-bridge circuit. Based on the first compensation control quantity, it determines the period control quantity and duty cycle control quantity of the switching drive signal.

[0109] The first compensation control quantity refers to the control quantity of the period or duty cycle of the switch drive signal that can compensate for the current error value. For example, the processing module 502 can determine the first compensation control quantity through a compensator. The compensator may include a PI controller, a Venable controller, a PR controller, a PID controller, etc., and this embodiment is not limited to this.

[0110] The control module 503 can be used to control the switch drive signal according to the periodic control quantity and the duty cycle control quantity. For example, the control module 503 can control the switch drive signal through a PWM controller according to the periodic control quantity and the duty cycle control quantity determined by the processing module 502.

[0111] In one embodiment of this application, the processing module 502 can be used to determine whether the first compensation control quantity exceeds the period value range of the switch drive signal.

[0112] In one embodiment of this application, optionally, the processing module 502 can be used to determine the periodic control quantity as the first compensation control quantity and the duty cycle control quantity as a first predetermined value when the first compensation control quantity satisfies the periodic value range of the switch drive signal. The first predetermined value may include an upper limit, a lower limit, or any preset value within the duty cycle range of the duty cycle, etc., and this embodiment is not limited in this regard. Optionally, for the case of small current, the first predetermined value may be the lower limit of the duty cycle. The control module 503 can be used to control the switch drive signal according to the periodic control quantity when the duty cycle control quantity is the first predetermined value.

[0113] In this embodiment of the application, when the processing module 502 takes the first compensation control quantity as the periodic control quantity when the first compensation control quantity is within the range of the switching drive signal period, the periodic control quantity is exactly within the range of the periodic control quantity required for the normal operation of the circuit.

[0114] In one embodiment of this application, optionally, the processing module 502 can be used to determine that the period control quantity is the lower limit of the period range of the switch drive signal, and determine the duty cycle control quantity as a first predetermined value, when the first compensation control quantity is less than the lower limit of the value range of the period of the switch drive signal. The control module 503 can be used to control the switch drive signal according to the period control quantity when the duty cycle control quantity is the first predetermined value.

[0115] In this embodiment, when the first compensation control quantity is less than the lower limit of the period range of the switch drive signal, if the processing module 502 determines that the first compensation control quantity is a period control quantity, then the period control quantity is below the range of period control quantities required for normal circuit operation, which may cause circuit failure. Therefore, when the first compensation control quantity is less than the lower limit of the period range of the switch drive signal, the processing module 502 determines that the period control quantity is equal to the lower limit of the period of the switch drive signal.

[0116] In some embodiments of this application, optionally, the processing module 502 can be used to convert the first compensation control quantity into a second compensation control quantity when the first compensation control quantity is greater than the upper limit of the value range of the period of the switch drive signal. The processing module 502 determines the period control quantity and the duty cycle control quantity based on the second compensation control quantity.

[0117] The second compensation control quantity refers to the control quantity corresponding to the duty cycle of the switch drive signal that can compensate for the error value. The second compensation control quantity can be determined based on the first compensation control quantity, and the determination method may include multiplying the first compensation control quantity by a specific coefficient, etc., which is not limited in this embodiment. The specific coefficient may include preset coefficient values, coefficient values ​​determined by functional relationships, coefficient values ​​determined by looking up a table, etc., which is not limited in this embodiment. Optionally, the second compensation control quantity may also include the compensation control quantity obtained by the compensator compensating for the current error value.

[0118] In the embodiments of this application, the circuit can control the switch drive signal through the duty cycle control quantity. When the current output of the circuit needs to increase, the duty cycle control quantity can be adjusted to control the switch drive signal by using a fixed period as the upper limit of the period, while avoiding switching losses.

[0119] In one embodiment of this application, the processing module 502 can be used to determine whether the second compensation control quantity exceeds the duty cycle value range of the switch drive signal.

[0120] In one embodiment of this application, optionally, the processing module 502 can be used to determine the duty cycle control quantity as the second compensation control quantity and determine the period control quantity as the upper limit of the period range of the switch drive signal when the second compensation control quantity is within the range of the duty cycle of the switch drive signal. The control module 503 can be used to control the switch drive signal according to the duty cycle control quantity when the period control quantity is the upper limit of the period range of the switch drive signal.

[0121] In this embodiment, the processing module 502 determines that the duty cycle control quantity is equal to the second compensation control quantity when the second compensation control quantity is within the range of the duty cycle of the switch drive signal. When the second compensation control quantity is within the range of the duty cycle of the switch drive signal, the second compensation control quantity is taken as the duty cycle control quantity, and the duty cycle control quantity is exactly within the range of the duty cycle control quantity required for normal circuit operation.

[0122] In one embodiment of this application, optionally, the processing module 502 can be used to determine that the duty cycle control quantity is the lower limit of the duty cycle range of the switch drive signal, and to determine that the period control quantity is the upper limit of the period range of the switch drive signal, when the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal. The control module 503 can be used to control the switch drive signal according to the duty cycle control quantity when the period control quantity is the upper limit of the period range of the switch drive signal.

[0123] In this embodiment, when the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal, the processing module 502 determines that the duty cycle control quantity is equal to the lower limit of the duty cycle range. Due to the characteristics of the aforementioned compensation control quantity, it is possible that the second compensation control quantity determined by the processing module 502 is less than the lower limit of the duty cycle range of the switch drive signal. When the second compensation control quantity is less than the lower limit of the duty cycle range, if the second compensation control quantity is taken as the duty cycle control quantity, it may result in the duty cycle control quantity being less than the minimum duty cycle control quantity required for normal circuit operation, thereby causing circuit failure. Therefore, when the second compensation control quantity is less than the lower limit of the duty cycle range, the duty cycle control quantity is taken as the lower limit of the duty cycle range.

[0124] In one embodiment of this application, optionally, the processing module 502 can be used to determine, when the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal, that the duty cycle control quantity is the upper limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal. The control module 503 can be used to control the switch drive signal according to the duty cycle control quantity when the period control quantity is the upper limit of the period range of the switch drive signal.

[0125] In this embodiment, when the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal, the processing module 502 determines that the duty cycle control quantity is equal to the upper limit of the duty cycle range. Due to the characteristics of the aforementioned compensation control quantity, it is possible that the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal. If the second compensation control quantity is taken as the duty cycle control quantity in this case, it may result in the duty cycle control quantity being greater than the maximum duty cycle control quantity required for normal circuit operation, thereby causing a circuit malfunction. Therefore, when the second compensation control quantity is greater than the upper limit of the duty cycle range, the duty cycle control quantity is taken as the upper limit of the duty cycle range.

[0126] This application also provides another device for reverse current control of a phase-shifted full-bridge circuit, which includes a memory and a processor, wherein the memory is used to store instructions, and the processor is used to read the instructions and execute the methods of the various embodiments of this application described above based on the instructions.

[0127] This application also provides a readable storage medium for storing a computer program for executing the methods of the various embodiments of this application described above.

[0128] This application also provides a phase-shifted full-bridge circuit, including the reverse current control device for the phase-shifted full-bridge circuit described in the foregoing embodiments of this application.

[0129] In the embodiments of this application, by adjusting the circuit switching cycle and duty cycle, a wide range of current control is achieved, which can meet the charging and discharging needs of the battery in various scenarios.

[0130] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for controlling the reverse current of a phase-shifted full-bridge circuit, characterized in that, include: The error value of the reverse input current is determined based on the sampled value of the reverse input current of the phase-shifted full-bridge circuit and the reference value of the reverse input current. Based on the error value, a first compensation control quantity for the switching drive signal of the phase-shifted full-bridge circuit is determined, wherein the first compensation control quantity is the compensation quantity for the error value, and the first compensation control quantity is the control quantity corresponding to the period or duty cycle of the switching drive signal. Based on the first compensation control quantity, the period control quantity and duty cycle control quantity of the switch drive signal are determined, wherein the period control quantity is within the range of the period of the switch drive signal, and the duty cycle control quantity is within the range of the duty cycle of the switch drive signal. The switching drive signal is controlled according to the period control amount and the duty cycle control amount.

2. The method according to claim 1, characterized in that, The step of determining the period control quantity and duty cycle control quantity of the switch drive signal based on the first compensation control quantity includes: If the first compensation control quantity is within the range of the period of the switch drive signal, the period control quantity is determined to be the first compensation control quantity, and the duty cycle control quantity is determined to be a first predetermined value.

3. The method according to claim 2, characterized in that, The step of determining the period control quantity and duty cycle control quantity of the switch drive signal based on the first compensation control quantity includes: When the first compensation control amount is less than the lower limit of the range of the period of the switch drive signal, the period control amount is determined to be the lower limit of the range of the period of the switch drive signal, and the duty cycle control amount is the first predetermined value.

4. The method according to any one of claims 1 to 3, characterized in that, The step of determining the period control quantity and duty cycle control quantity of the switch drive signal based on the first compensation control quantity includes: When the first compensation control quantity is greater than the upper limit of the value range of the period of the switch drive signal, the first compensation control quantity is converted into a second compensation control quantity, wherein the second compensation control quantity is the control quantity corresponding to the duty cycle of the switch drive signal. The cycle control quantity and the duty cycle control quantity are determined based on the second compensation control quantity.

5. The method according to claim 4, characterized in that, The step of determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: If the second compensation control quantity is within the range of the duty cycle of the switch drive signal, the duty cycle control quantity is determined as the second compensation control quantity, and the period control quantity is the upper limit of the range of the period of the switch drive signal.

6. The method according to claim 4, characterized in that, The step of determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: When the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal, the duty cycle control quantity is determined to be the lower limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal.

7. The method according to claim 4, characterized in that, The step of determining the period control quantity and the duty cycle control quantity based on the second compensation control quantity includes: When the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal, the duty cycle control quantity is determined to be the upper limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal.

8. A reverse current control device for a phase-shifted full-bridge circuit, characterized in that, include: The acquisition module is used to acquire the sampled value of the reverse input current of the phase-shifted full-bridge circuit, and to acquire the reference value of the reverse input current; The processing module is used to determine the error value of the reverse input current based on the sampled value of the current and the reference value of the current; Based on the error value, a first compensation control quantity for the switching drive signal of the phase-shifted full-bridge circuit is determined, wherein the first compensation control quantity is a compensation amount for the error value, and the first compensation control quantity is a control quantity corresponding to the period or duty cycle of the switching drive signal; based on the first compensation control quantity, a period control quantity and a duty cycle control quantity for the switching drive signal are determined, wherein the period control quantity is within the range of the period of the switching drive signal, and the duty cycle control quantity is within the range of the duty cycle of the switching drive signal. The control module is used to control the switch drive signal according to the period control quantity and the duty cycle control quantity.

9. The apparatus according to claim 8, characterized in that, The processing module is used to determine the period control quantity as the first compensation control quantity and the duty cycle control quantity as a first predetermined value when the first compensation control quantity is within the range of the period of the switch drive signal.

10. The apparatus according to claim 9, characterized in that, The processing module is used to determine that the period control quantity is the lower limit of the period range of the switch drive signal, and the duty cycle control quantity is the first predetermined value, when the first compensation control quantity is less than the lower limit of the period range of the switch drive signal.

11. The apparatus according to any one of claims 8 to 10, characterized in that, The processing module is used to convert the first compensation control quantity into a second compensation control quantity when the first compensation control quantity is greater than the upper limit of the value range of the period of the switch drive signal, wherein the second compensation control quantity is the control quantity corresponding to the duty cycle of the switch drive signal; and to determine the period control quantity and the duty cycle control quantity based on the second compensation control quantity.

12. The apparatus according to claim 11, characterized in that, The processing module is used to determine the duty cycle control quantity as the second compensation control quantity when the second compensation control quantity is within the range of the duty cycle of the switch drive signal, and the period control quantity is the upper limit of the range of the period of the switch drive signal.

13. The apparatus according to claim 11, characterized in that, The processing module is used to determine, when the second compensation control quantity is less than the lower limit of the duty cycle range of the switch drive signal, that the duty cycle control quantity is the lower limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal.

14. The apparatus according to claim 11, characterized in that, The processing module is used to determine that the duty cycle control quantity is the upper limit of the duty cycle range of the switch drive signal, and the period control quantity is the upper limit of the period range of the switch drive signal, when the second compensation control quantity is greater than the upper limit of the duty cycle range of the switch drive signal.

15. A phase-shifted full-bridge circuit, characterized in that, Includes the reverse current control device according to any one of claims 8 to 14.

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