Boost circuit control method, boost circuit, and electronic module

Abstract

This application provides a boost circuit control method, a boost circuit, and an electronic module. The boost circuit control method includes: acquiring the input voltage of the boost circuit; determining the switching state of a first switching device, the switching state of a second switching device, and a preset given voltage for the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds. This application determines the switching state of the first and second switching devices by comparing the input voltage of the boost circuit with different preset comparison thresholds, thereby switching the boost circuit between boost mode and pass-through mode. The switching boundary is clear, the switching process is fast, and the boost circuit is not kept in transition mode for extended periods, reducing heat generation and eliminating the need for special heat dissipation devices, thus reducing the overall size of the electronic module.

Description

Technical Field

[0001] This application belongs to the field of power electronics technology, and in particular relates to a boost circuit control method, a boost circuit, and an electronic module. Background Technology

[0002] Currently, boost circuits are used at the front end of various load devices that require boost voltage. For example, in photovoltaic systems, a boost circuit combined with an inverter is generally used to regulate the output voltage of the photovoltaic current. Because the output voltage of photovoltaic current is easily affected by weather, its range is generally wide. When the output voltage of the photovoltaic current is low, a boost mode can be used to increase the output voltage to meet the minimum inverter bus voltage requirement on the DC side of the inverter. When the output voltage of the photovoltaic current is high, a relay pass-through mode can be used to improve boost efficiency.

[0003] However, existing boost circuits generally have blurred switching boundaries and slow switching processes. When the input voltage changes rapidly, the boost circuit remains in transition mode for extended periods, often generating a large amount of heat. This places high demands on the heat dissipation of the boost circuit; otherwise, internal components may be burned out. Summary of the Invention

[0004] The purpose of this application is to provide a boost circuit control method, a boost circuit, and an electronic module, which aims to solve the problems of slow switching process and high heat dissipation requirements of traditional boost circuit control methods.

[0005] To achieve the above objectives, in a first aspect, embodiments of this application provide a boost circuit control method, including:

[0006] Obtain the input voltage of the boost circuit;

[0007] Based on the input voltage of the boost circuit and different preset comparison thresholds, the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit are determined.

[0008] In one possible implementation of the first aspect, determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes:

[0009] The preset comparison threshold includes multiple comparison thresholds. Based on the input voltage of the boost circuit and the multiple comparison thresholds, the switching state of the first switching device, the switching state of the second switching device, and the multiple preset given voltages are determined respectively.

[0010] In another possible implementation of the first aspect, before the input voltage based on the boost circuit is compared with different preset comparison thresholds, the method further includes:

[0011] The preset comparison threshold includes a first comparison threshold. When the input voltage of the boost circuit is less than the first comparison threshold, the first switching device is controlled to open and the second switching device is controlled to chop, and the preset given voltage is determined to be the first given voltage.

[0012] When the input voltage of the boost circuit is greater than or equal to the first comparison threshold, and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close and the second switching device is controlled to block the wave, and the preset given voltage is determined as the second given voltage.

[0013] Wherein, the first given voltage is greater than the second given voltage.

[0014] In another possible implementation of the first aspect, determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes:

[0015] The preset comparison threshold includes a second comparison threshold and a third comparison threshold.

[0016] When the first switching device is in the open state and the second switching device is in the chopper working state, when the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is determined as the second given voltage; when the input voltage of the boost circuit is greater than the third comparison threshold, the second switching device blocks the waveform and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close.

[0017] When the first switching device is in the closed state and the second switching device is in the blocked state, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the first switching device is controlled to open, and the preset given voltage is determined to be the first given voltage;

[0018] Wherein, the second comparison threshold is greater than the third comparison threshold, the first given voltage is greater than the second comparison threshold, and the second given voltage is less than the third comparison threshold.

[0019] In another possible implementation of the first aspect, the first comparison threshold includes a regulated center value, the second comparison threshold is equal to the regulated center value plus a first offset, and the third comparison threshold is equal to the regulated center value minus a second offset.

[0020] In another possible implementation of the first aspect, the boost circuit control method further includes:

[0021] When the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is linearly reduced from the first given voltage to the second given voltage;

[0022] Alternatively, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the preset given voltage is linearly increased from the second given voltage to the first given voltage.

[0023] Secondly, embodiments of this application provide a boost circuit, including a first inductor, a first MOSFET, a first diode, a first switch, and semiconductor devices;

[0024] One end of the first inductor, one end of the first switch, and the positive terminal of the first diode are all connected to the input voltage. The other end of the first inductor is electrically connected to one end of the semiconductor device and the drain of the first MOS transistor, respectively. The other end of the semiconductor device, the other end of the first switch, and the negative terminal of the first diode are all connected to the output voltage. The source of the first MOS transistor is grounded.

[0025] In another possible implementation of the second aspect, the semiconductor device includes a second diode;

[0026] The positive terminal of the second diode is electrically connected to the common terminal of the first inductor and the first MOSFET, and the negative terminal of the second diode is connected to the output voltage.

[0027] In another possible implementation of the second aspect, the semiconductor device includes a second MOS transistor;

[0028] The source of the second MOSFET is electrically connected to the common terminal of the first inductor and the first MOSFET, and the drain of the second MOSFET is connected to the output voltage.

[0029] Thirdly, embodiments of this application provide an electronic module including the aforementioned boost circuit.

[0030] The beneficial effects of this application embodiment compared with the prior art are as follows: The above-mentioned boost circuit control method determines the switching state of the first switching device and the second switching device by comparing the input voltage of the boost circuit with different preset comparison thresholds, thereby switching the boost mode and the pass-through mode of the boost circuit. The switching boundary is clear, the switching process is fast, and the boost circuit will not be in the transition mode for a long time, reducing heat generation, eliminating the need for special heat dissipation devices, and reducing the size of the entire electronic module. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a schematic diagram of a first structure of a boost circuit provided in an embodiment of this application;

[0033] Figure 2 This is a schematic diagram of a second structure of the boost circuit provided in the embodiments of this application;

[0034] Figure 3 This is a schematic diagram of the wave generation structure of the boost circuit provided in the embodiments of this application;

[0035] Figure 4 A flowchart of the boost circuit control method provided in the embodiments of this application;

[0036] Figure 5 This is a schematic diagram of the switching process of the boost circuit provided in the embodiments of this application. Detailed Implementation

[0037] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0038] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0039] In one embodiment of this application, the boost circuit generally operates in two modes: boost mode and pass-through mode. When the input voltage of the boost circuit is low, it can use boost mode to boost the input voltage. When the input voltage is high, it can use pass-through mode, where the input voltage is directly output through the boost circuit. The boost circuit typically determines its operating mode based on only a comparison threshold, resulting in a blurred switching boundary and a slow switching process. When the input voltage changes rapidly, the boost circuit remains in transition mode for extended periods, often leading to the generation of significant heat. This necessitates a dedicated space for a heatsink, resulting in a larger overall size of the boost circuit.

[0040] Therefore, this application provides a boost circuit control method, which determines the switching state of the first switching device and the second switching device by comparing the input voltage of the boost circuit with different preset comparison thresholds, thereby switching the boost mode and the pass-through mode of the boost circuit. The switching boundary is clear, the switching process is fast, and the boost circuit will not be in the transition mode for a long time, reducing heat generation, eliminating the need for special heat dissipation devices, and reducing the size of the entire electronic module.

[0041] The boost circuit provided in this application will be described exemplarily below with reference to the accompanying drawings.

[0042] Figure 1 This is a schematic diagram of a first structure of a boost circuit provided in an embodiment of this application. Figure 1 As shown, exemplarily, a boost circuit includes a first inductor L1, a first MOSFET Q1, a first diode D1, a first switching device S1, a second diode D2, a first capacitor C1, and a second capacitor C2.

[0043] One end of the first inductor L1, one end of the first switching device S1, and the anode of the first diode D1 are all connected to the input voltage Vin. The other end of the first inductor L1 is electrically connected to the anode of the second diode D2 and the drain of the first MOSFET Q1, respectively. The cathode of the second diode D2, the other end of the first switching device S1, and the cathode of the first diode D1 are all connected to the output voltage Vdc. The source of the first MOSFET Q1 is grounded, and the gate of the first MOSFET is connected to an external modulation signal (e.g., a pulse width modulation signal, PWM). The two ends of the first capacitor C1 are connected to the two ends of the input voltage Vin, and the two ends of the second capacitor C2 are connected to the two ends of the output voltage Vdc.

[0044] In this embodiment, the first MOSFET Q1 and the second diode D2 form a half-bridge network. When the first switching device S1 is closed, the output voltage Vdc is equal to the input voltage Vin, and the input voltage Vin is directly supplied to the output voltage Vdc (i.e., the bus), and the boost circuit is in shoot-through mode. When the first switching device S1 is open and the first MOSFET Q1 operates through an external modulation signal, the boost circuit is in boost mode, and the output voltage Vdc is greater than the input voltage Vin. When the first switching device S1 is open and the first MOSFET Q1 is not operating, the input voltage Vin is mainly electrically connected to the output Vdc through the first diode D1, and the output voltage Vdc is not lower than the input voltage Vin. That is, when the bus at the output end is loaded, the output voltage Vdc and the input voltage Vin eventually tend to be approximately equal. When the bus at the output end is unloaded, the initial voltage of the bus cannot discharge or discharges slowly, and the bus voltage may be greater than the input voltage Vin.

[0045] In this application embodiment, the boost circuit generally includes three operating modes:

[0046] (1) Boost mode: When the boost circuit is in boost mode, the first switching device S1 must be disconnected, otherwise current will flow through the first switching device S1, which may cause burnout. The first MOSFET Q1 is in chopping operation state, and the output voltage (i.e. the bus voltage) Vdc is greater than the input voltage Vin.

[0047] (2) Straight-through mode: When the boost circuit is in the straight-through mode, the input voltage Vin and the output voltage Vdc are shorted through the first switching device S1 and the voltages are the same. The first inductor L1, the first MOSFET Q1 and the second diode D2 are bypassed by the first switching device S1 and no current flows through them.

[0048] (3) Transition mode: When the boost circuit is in the transition mode of the above two normal working modes, the first switching device S1 is open, the first diode D1 freewheels for a short time, the current conversion is transitioned, or the boost circuit stops, but is not yet in the state where the first switching device S1 is closed.

[0049] Furthermore, in this embodiment, one of the necessary conditions for the first switching device S1 to close is that the difference between the input voltage Vin and the output voltage Vdc is within a certain range; otherwise, the capacitor discharge current is large, which can easily burn out the first switching device S1. The first diode D1 is generally a rectifier diode with a low voltage drop. When the boost circuit is not working, the first diode D1 receives most of the current. Therefore, by controlling the freewheeling time of the first diode D1, the freewheeling conduction time of the boost circuit can be greatly shortened, and the first diode D1 requires less heat dissipation or a heat sink. The first switching device S1 can be a relay.

[0050] Figure 2This is a schematic diagram of a second structure of the boost circuit provided in an embodiment of this application. (See attached diagram.) Figure 2 As shown, exemplarily, a boost circuit includes a first inductor L1, a first MOSFET Q1, a first diode D1, a first switching device S1, a second MOSFET Q2, a first capacitor C1, and a second capacitor C2.

[0051] One end of the first inductor L1, one end of the first switching device S1, and the anode of the first diode D1 are all connected to the input voltage Vin. The other end of the first inductor L1 is electrically connected to the source of the second MOSFET Q2 and the drain of the first MOSFET Q1, respectively. The drain of the second MOSFET Q2, the other end of the first switching device S1, and the cathode of the first diode D1 are all connected to the output voltage Vdc. The source of the first MOSFET Q1 is grounded, and the gate of the first MOSFET is connected to an external modulation signal (e.g., a pulse width modulation signal, PWM). The two ends of the first capacitor C1 are connected to the two ends of the input voltage Vin, and the two ends of the second capacitor C2 are connected to the two ends of the output voltage Vdc.

[0052] In the embodiments of this application, with Figure 1 The difference in the embodiment is that the second diode D2 is replaced with the second MOSFET Q2, and the overall working principle of the boost circuit is the same. Figure 1 Similarly, the main difference lies in the waveform control. When the semiconductor device is the second diode D2, due to the reverse cutoff effect of the diode, the bus can only be adjusted in one direction, and the discharge depends on the load, unable to flow in reverse to the input side. When the semiconductor device is the second MOSFET Q2, the current in the bidirectional boost circuit can flow in both directions, and when the bus is under voltage, the feedforward waveform of the second MOSFET Q2 needs to be activated.

[0053] Figure 3 This is a schematic diagram of the wave generation structure of the boost circuit provided in an embodiment of this application. Figure 3 As shown, the voltage loop controls the bus voltage, and the inner current loop controls the inductor current. When the boost circuit operates in the stable control mode of the bus voltage Vdc, Vdc_ref is the bus given voltage, Vdc is the bus sampling feedback, IL* is the voltage loop output (i.e., the inductor current given), IL is the inductor current feedback, and Vc is the current loop output waveform. The PWM wave of the first MOSFET Q1 is generated by limiting and modulating the waveform, and then applied to the gate of the first MOSFET Q1 by the drive circuit.

[0054] In this embodiment, when the downstream stage of the bus voltage uses an inverter or other topology, the bus voltage is required to meet a certain range (i.e., above the minimum voltage). For example, when a three-phase inverter is used downstream of the bus voltage, the minimum bus voltage requirement is above 600V (the specific voltage value depends on the input voltage and topology wiring). Simultaneously, considering grid voltage fluctuations, the input voltage can be set to around 650V. When the input voltage Vin is below 650V, the boost circuit operates in boost mode to stabilize the bus voltage at 650V. When the input voltage Vin is greater than or equal to 650V, a shoot-through mode can be used to improve the efficiency of the boost circuit. However, when the input voltage gradually increases from a low voltage to approach or even exceed 650V, determining the critical state becomes difficult. The bypassed first diode D1 will be in shoot-through mode for an extended period. If the second diode D2 is not equipped with a heat dissipation device, it may burn out. Therefore, it is necessary to quickly determine the operating mode of the boost circuit to reduce the continuous heat dissipation of the second diode D2.

[0055] Therefore, this application provides a boost circuit control method. The following description, in conjunction with the accompanying drawings, provides illustrative examples of the boost circuit control method provided by this application: Figure 4 A flowchart of the boost circuit control method provided in the embodiments of this application is shown below. Figure 4 As shown, for ease of explanation, only the parts relevant to this embodiment are shown, and are described in detail below: Exemplarily, a boost circuit control method includes:

[0056] S101. Obtain the input voltage of the boost circuit.

[0057] S102. Based on the input voltage of the boost circuit and different preset comparison thresholds, determine the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit.

[0058] In this embodiment, the input voltage of the boost circuit is first obtained. Then, based on the input voltage of the boost circuit and different preset comparison thresholds, different operating modes of the boost circuit are determined, such as boost mode or shoot-through mode. The switching states of the first switching device, the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit are determined, thereby enabling rapid switching between the boost mode and shoot-through mode of the boost circuit. The switching boundary is clear, preventing the boost circuit from being in transition mode for a long time, reducing heat generation, eliminating the need for special heat dissipation devices, and reducing the size of the entire electronic module.

[0059] For example, determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes:

[0060] The preset comparison thresholds include multiple comparison thresholds. Based on the input voltage of the boost circuit and the multiple comparison thresholds, the switching state of the first switching device, the switching state of the second switching device, and multiple preset given voltages are determined respectively.

[0061] In this embodiment, the preset comparison threshold may include multiple comparison thresholds. Different comparison thresholds can be set according to the different current operating modes of the boost circuit. Then, the input voltage of the boost circuit is compared with the different comparison thresholds to determine the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of multiple boost circuits, so that the output terminal of the boost circuit can obtain the target voltage and drive the subsequent load to work.

[0062] For example, before comparing the input voltage of the boost circuit with different preset comparison thresholds, the method further includes:

[0063] The preset comparison threshold includes a first comparison threshold. When the input voltage of the boost circuit is less than the first comparison threshold, the first switching device is controlled to open and the second switching device is controlled to chop, and the preset given voltage is determined to be the first given voltage.

[0064] When the input voltage of the boost circuit is greater than or equal to the first comparison threshold, and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close and the second switching device is controlled to block the wave, and the preset given voltage is determined as the second given voltage.

[0065] Wherein, the first given voltage is greater than the second given voltage.

[0066] In this embodiment, before the input voltage of the boost circuit is compared with different preset comparison thresholds, i.e., before the boost circuit is started, the preset comparison thresholds may include a first comparison threshold, which may specifically be the voltage regulation center value V0. When the input voltage Vin of the boost circuit is less than the first comparison threshold (voltage regulation center value V0), the first switching device S1 is turned off and the second switching device Q1 is operated for chopping, the preset given voltage Vdc_ref is determined to be the first given voltage V1, and the preset comparison threshold is set to the second comparison threshold V3, that is, the boost circuit is adjusted to boost mode.

[0067] When the input voltage Vin of the boost circuit is greater than or equal to the first comparison threshold (the voltage regulation center value V0), and the difference between the input voltage Vin and the output voltage Vdc of the boost circuit is less than or equal to the error range, the first switching device S1 is closed and the second switching device Q1 is blocked, the preset given voltage Vdc_ref is determined as the second given voltage V2, and the preset comparison threshold is set as the third comparison threshold V4, that is, the boost circuit is adjusted to the shoot-through mode.

[0068] When the input voltage Vin of the boost circuit is greater than or equal to the first comparison threshold (the regulated center value V0), and the difference between the input voltage Vin and the output voltage Vdc of the boost circuit is greater than the error range, the boost circuit is in transition mode and no action is taken temporarily. This is because the boost circuit will only switch from boost mode to shoot-through mode if it is guaranteed that the first switching device S1 will not generate a large current and burn out after closing. Conversely, it will remain in transition mode until the difference between the input voltage Vin and the output voltage Vout of the boost circuit is greater than the error range, at which point the first switching device S1 will close.

[0069] In this embodiment, the first given voltage V1 is greater than the second given voltage V2, the second comparison threshold V3 is greater than the third comparison threshold V4, and the first given voltage V1 is greater than the second comparison threshold V3, while the second given voltage V2 is less than the third comparison threshold V4. This allows a difference to be generated between the input voltage Vin and the output voltage Vout, ensuring a switching margin. In this embodiment, to more accurately determine the operating mode of the boost circuit and avoid the current-carrying switching of the first switching device S1 that might result from the boost circuit being in a transition mode for an extended period, a corresponding adjustment hysteresis is also set for the preset given voltage of the boost circuit's output voltage control loop, namely the first given voltage V1 and the second given voltage V2. This, together with the preset comparison threshold of the input voltage, completes the operating mode switching process of the boost circuit.

[0070] For example, determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes:

[0071] The preset comparison thresholds include a second comparison threshold and a third comparison threshold. When the first switching device is in the open state and the second switching device is in the chopping operation state, if the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is determined as the second given voltage. When the input voltage of the boost circuit is greater than the third comparison threshold, the second switching device blocks the waveform, and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close.

[0072] When the first switching device is in the closed state and the second switching device is in the blocked state, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the first switching device is controlled to open, and the preset given voltage is determined as the first given voltage.

[0073] In this embodiment, the preset comparison threshold includes a second comparison threshold V3 and a third comparison threshold V4. When the first switching device S1 is in the off state and the second switching device Q1 is in the chopper working state (i.e. when the boost circuit is currently in boost mode), when the input voltage Vin of the boost circuit is greater than or equal to the second comparison threshold V3, the preset given voltage Vdc_ref is updated from the first given voltage V1 to the second given voltage V2, and the preset comparison threshold is updated from the second comparison threshold V3 to the third comparison threshold V4, in preparation for switching the working mode of the boost circuit to the pass-through mode.

[0074] When the input voltage Vin of the boost circuit is greater than the third comparison threshold V4, the second switching device Q1 blocks the output, and the difference between the input voltage Vin and the output voltage Vdc of the boost circuit is less than or equal to the error range, the first switching device S1 is closed, switching the boost mode of the boost circuit from boost mode to pass-through mode. When the input voltage Vin of the boost circuit is greater than the third comparison threshold V4, the second switching device Q1 blocks the output, and the difference between the input voltage Vin and the output voltage Vdc of the boost circuit is greater than the error range, the boost circuit is put into a waiting state until the difference between the input voltage Vin and the output voltage Vdc of the boost circuit does not exceed the error range, at which point it enters pass-through mode.

[0075] When the first switching device S1 is in the closed state and the second switching device Q1 is in the blocked state (i.e., when the boost circuit is currently in the pass-through mode), when the input voltage Vin of the boost circuit is less than or equal to the third comparison threshold V4, the preset comparison threshold of the boost circuit is updated from the third comparison threshold V4 to the second comparison threshold V3, the first switching device S1 is opened, and the preset given voltage Vdc_ref is updated from the second given voltage V2 to the first given voltage V1, that is, the working mode of the boost circuit is switched from the pass-through mode to the boost mode.

[0076] For example, the first comparison threshold includes the regulated center value, the second comparison threshold is equal to the regulated center value plus the first offset, and the third comparison threshold is equal to the regulated center value minus the second offset.

[0077] In this embodiment, the first comparison threshold may include the regulated center value V0, the second comparison threshold V3 is equal to the regulated center value V0 plus the first offset ΔV1, and the third comparison threshold V4 is equal to the regulated center value V0 minus the second offset ΔV2, so that the preset comparison threshold of the input voltage has a certain hysteresis, which can fluctuate within the range above and below the regulated center value V0 according to the voltage fluctuation, ensuring reliable switching fluctuation or anti-jitter switching.

[0078] For example, the boost circuit control method further includes:

[0079] When the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is linearly reduced from the first given voltage to the second given voltage.

[0080] Alternatively, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the preset given voltage is linearly increased from the second given voltage to the first given voltage.

[0081] In this embodiment, when the input voltage Vin of the boost circuit is greater than or equal to the second comparison threshold V3, the preset given voltage Vdc_ref is linearly decreased from the first given voltage V1 to the second given voltage V2, thereby completing the rapid decrease process of the preset given voltage Vdc_ref from the first given voltage V1 to the second given voltage V2. Alternatively, when the input voltage Vin of the boost circuit is less than or equal to the third comparison threshold V4, the preset given voltage Vdc_ref is linearly increased from the second given voltage V2 to the first given voltage V1, thereby completing the rapid increase process of the preset given voltage Vdc_ref from the second given voltage V2 to the first given voltage V1.

[0082] Figure 5 This is a schematic diagram illustrating the switching process of the boost circuit provided in an embodiment of this application. Figure 5 As shown, when the input voltage Vin slowly increases from a low voltage or slowly decreases from a high voltage, it generally involves the following two processes:

[0083] (1) Switch from boost mode to pass-through mode: such as Figure 5 As shown,

[0084] Before time t0, the boost circuit operates in boost mode. The preset comparison threshold is the second comparison threshold V3, the preset given voltage Vdc_ref is the first given voltage V1, the output voltage Vdc is also V1, and the inductor current IL decreases accordingly as the input voltage increases.

[0085] When the boost circuit is at time t0, and the input voltage Vin is greater than or equal to the second comparison threshold V3, the boost circuit enters the transition mode, linearly reduces the preset given voltage setting Vdc_ref from the current first given voltage V1 to the second given voltage V2, and updates the preset comparison threshold from the second comparison threshold V3 to the third comparison threshold V4.

[0086] When the boost circuit is at time t1, and the preset given voltage Vdc_ref is set to be equal to the input voltage Vin, the given inductor current IL gradually decreases to 0, and the corresponding current Id of the first diode D1 gradually increases.

[0087] When the boost circuit is at time t2, the boost circuit switching is complete.

[0088] When the boost circuit is delayed for a certain period of time or after time t3, the first switching device S1 closes and enters the shoot-through mode.

[0089] (2) Switch from through mode to boost mode:

[0090] Before time t4, the boost circuit operates in shoot-through mode. The preset comparison threshold is the second comparison threshold V4, and the preset given voltage Vdc_ref is the second given voltage V2. The output voltage Vdc is equal to the input voltage Vin. Under the condition of resistive load, the inductor current IL decreases accordingly as the input voltage decreases, and the input voltage Vin also gradually decreases.

[0091] When the boost circuit is at time t4, the input voltage Vin is less than or equal to the second comparison threshold V4. The boost circuit enters the transition mode, updates the preset comparison threshold from the third comparison threshold V4 to the second comparison threshold V3, and disconnects the first switching device S1. The delay ensures reliable disconnection.

[0092] When the boost circuit is at time t5, the preset given voltage Vdc_ref is linearly increased from the current second given voltage V2 to the first given voltage V1.

[0093] When the boost circuit is at time t6, IL gradually increases to the load current, and the current Id of the first diode D1 gradually decreases to 0.

[0094] When the boost circuit is at time t7, it enters a stable boost mode, and the output voltage Vdc remains constant at the first given voltage V1, completing the switching process.

[0095] For example, an electronic module includes a boost circuit.

[0096] In this embodiment, the boost circuit is placed inside the electronic module. By comparing the input voltage of the boost circuit with different preset comparison thresholds, the switching state of the first switching device and the switching state of the second switching device are determined, thereby switching the boost mode and the pass-through mode of the boost circuit. The switching boundary is clear, the switching process is fast, and the boost circuit will not be in the transition mode for a long time, reducing heat generation. There is no need to add a special heat dissipation device, thus reducing the size of the entire electronic module.

[0097] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0098] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is merely an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiments can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. Furthermore, the specific names of the functional units and modules are only for easy differentiation and are not intended to limit the scope of protection of this application. The specific working process of the units and modules in the above system can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0099] In the above embodiments, the descriptions of each embodiment have different focuses. For parts that are not described in detail or recorded in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0100] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0101] In the embodiments provided in this application, it should be understood that the disclosed boost circuit control method can be implemented in other ways. For example, the boost circuit control method embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0102] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0103] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0104] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be included within the protection scope of this application.

Claims

1. A method for controlling a boost circuit, characterized in that, include: Obtain the input voltage of the boost circuit; Based on the input voltage of the boost circuit and different preset comparison thresholds, the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit are determined. Before comparing the input voltage based on the boost circuit with different preset comparison thresholds, the method further includes: The preset comparison threshold includes a first comparison threshold. When the input voltage of the boost circuit is less than the first comparison threshold, the first switching device is controlled to open and the second switching device is controlled to chop, and the preset given voltage is determined to be the first given voltage. When the input voltage of the boost circuit is greater than or equal to the first comparison threshold, and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close and the second switching device is controlled to block the wave, and the preset given voltage is determined as the second given voltage. Wherein, the first given voltage is greater than the second given voltage.

2. The boost circuit control method as described in claim 1, characterized in that, The step of determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes: The preset comparison threshold includes multiple comparison thresholds. Based on the input voltage of the boost circuit and the multiple comparison thresholds, the switching state of the first switching device, the switching state of the second switching device, and the multiple preset given voltages are determined respectively.

3. The boost circuit control method as described in claim 1, characterized in that, The step of determining the switching state of the first switching device, the switching state of the second switching device, and the preset given voltage of the output voltage control loop of the boost circuit based on the input voltage of the boost circuit and different preset comparison thresholds includes: The preset comparison threshold includes a second comparison threshold and a third comparison threshold. When the first switching device is in the open state and the second switching device is in the chopper working state, when the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is determined as the second given voltage; when the input voltage of the boost circuit is greater than the third comparison threshold, the second switching device blocks the waveform and the difference between the input voltage and the output voltage of the boost circuit is less than or equal to the error range, the first switching device is controlled to close. When the first switching device is in the closed state and the second switching device is in the blocked state, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the first switching device is controlled to open, and the preset given voltage is determined to be the first given voltage; Wherein, the second comparison threshold is greater than the third comparison threshold, the first given voltage is greater than the second comparison threshold, and the second given voltage is less than the third comparison threshold.

4. The boost circuit control method as described in claim 3, characterized in that, The first comparison threshold includes the regulated center value, the second comparison threshold is equal to the regulated center value plus a first offset, and the third comparison threshold is equal to the regulated center value minus a second offset.

5. The boost circuit control method as described in claim 3, characterized in that, The boost circuit control method further includes: When the input voltage of the boost circuit is greater than or equal to the second comparison threshold, the preset given voltage is linearly reduced from the first given voltage to the second given voltage; Alternatively, when the input voltage of the boost circuit is less than or equal to the third comparison threshold, the preset given voltage is linearly increased from the second given voltage to the first given voltage.

6. A boost circuit using the boost circuit control method according to any one of claims 1-5, characterized in that, It includes a first inductor, a first MOSFET, a first diode, a first switch, and semiconductor devices; One end of the first inductor, one end of the first switch, and the positive terminal of the first diode are all connected to the input voltage. The other end of the first inductor is electrically connected to one end of the semiconductor device and the drain of the first MOS transistor, respectively. The other end of the semiconductor device, the other end of the first switch, and the negative terminal of the first diode are all connected to the output voltage. The source of the first MOS transistor is grounded.

7. The boost circuit as described in claim 6, characterized in that, The semiconductor device includes a second diode; The positive terminal of the second diode is electrically connected to the common terminal of the first inductor and the first MOSFET, and the negative terminal of the second diode is connected to the output voltage.

8. The boost circuit as described in claim 6, characterized in that, The semiconductor device includes a second MOS transistor; The source of the second MOSFET is electrically connected to the common terminal of the first inductor and the first MOSFET, and the drain of the second MOSFET is connected to the output voltage.

9. An electronic module, characterized in that, Includes the boost circuit as described in any one of claims 6-8.

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