A charging control method, a charging control circuit, and an electronic device

Abstract

The application discloses a charging control method, a charging control circuit and electronic equipment. The charging control method comprises the following steps: acquiring a characteristic electrical parameter of a power supply adjusting circuit; gradually adjusting and increasing a minimum duty ratio to obtain a first duty ratio by using a first monotonic function; generating a first control signal by using the first duty ratio modulation, and sending the first control signal to a resonant isolation transformer circuit; when the first duty ratio is not less than a set duty ratio, the first duty ratio is equal to the set duty ratio; performing proportional integral operation on a first error value between a target bus voltage and a bus output voltage to obtain a first adjusting output value; generating a second control signal by using the first adjusting output value modulation, and sending the second control signal to a voltage conversion circuit to trigger the voltage conversion circuit to change a switching state, so as to adjust the bus output voltage. In the above manner, the charging control method can effectively ensure the safety of persons and equipment in energy storage charging, and improve the reliability and stability of energy storage charging.

Description

Technical Field

[0001] This application relates to the field of circuit technology, and in particular to a charging control method, a charging control circuit, and an electronic device. Background Technology

[0002] In recent years, with the development of new energy charging systems such as photovoltaic, wind power, and geothermal energy, how to achieve good operation of energy storage charging in fluctuating power input scenarios has become one of the hot research topics in the industry.

[0003] However, in related technologies, new energy charging systems generally connect the power generation module directly to the voltage converter, and then connect the voltage converter to the battery and load to achieve energy storage charging. As a result, due to the lack of electrical isolation between the power generation module and the battery, there is a risk of electric shock. In addition, in the event of lightning strikes or surges, fault currents can be directly conducted, resulting in low system reliability. The charging start-up and operation phase can also cause impacts on the battery and load. Summary of the Invention

[0004] The main technical problem addressed by this application is to provide a charging control method, charging control circuit, and electronic device that can solve the problems of electric shock risk in energy storage charging in related technologies; the direct conduction of fault current under conditions such as lightning strikes and surges, resulting in low system reliability; and the impact on the battery and load during the charging start-up and operation phase.

[0005] To solve the above-mentioned technical problems, this application adopts a technical solution as follows: A charging control method is provided, applied in a power supply regulation circuit. The charging control method includes: acquiring characteristic electrical parameters of the power supply regulation circuit; wherein the power supply regulation circuit includes a voltage conversion circuit and a resonant isolation transformer circuit, and the characteristic electrical parameters include the power input and bus output voltage in the voltage conversion circuit; detecting whether the power input is within a first threshold range; if the power input is within the first threshold range, gradually increasing the minimum duty cycle using a first monotonic function to obtain a first duty cycle; generating a first control signal using the first duty cycle modulation; sending the first control signal to the resonant isolation transformer circuit to trigger the resonant isolation transformer circuit to change its switching state; detecting whether the first duty cycle is less than a set duty cycle; if the first duty cycle is not less than the set duty cycle, setting the first duty cycle equal to the set duty cycle; performing a proportional-integral operation on a first error value between the target bus voltage and the bus output voltage to obtain a first regulated output value; generating a second control signal using the first regulated output value modulation; and sending the second control signal to the voltage conversion circuit to trigger the voltage conversion circuit to change its switching state, thereby regulating the bus output voltage.

[0006] The charging control method further includes: if the first duty cycle is less than the set duty cycle, returning to the step of gradually increasing the minimum duty cycle using a first monotonic function to obtain the first duty cycle.

[0007] The resonant isolation transformer circuit includes a primary-side resonant switching sub-circuit, an isolation transformer, and a secondary-side switching sub-circuit. A voltage conversion circuit is coupled to the primary-side resonant switching sub-circuit and used for coupling with a DC power supply. The isolation transformer is coupled to both the primary-side resonant switching sub-circuit and the secondary-side switching sub-circuit. The secondary-side switching sub-circuit is used for coupling with an energy storage power supply circuit. Characteristic electrical parameters also include the energy storage charging voltage and energy storage charging current in the secondary-side switching sub-circuit. After sending a second control signal to the voltage conversion circuit to trigger it to change its switching state and thus regulate the bus output voltage, the circuit further includes: detecting whether the power input remains within a second threshold range for a first duration; if the power input remains within the second threshold range for a first duration, detecting whether the bus output voltage is within a third threshold range; if the bus output voltage is within the third threshold range, using a second monotonic function to gradually increase the minimum duty cycle to obtain a second duty cycle; using the second duty cycle to modulate and generate a third control signal; and sending the third control signal to the secondary-side switching sub-circuit to trigger it to change its switching state, thereby regulating the charging and discharging of the energy storage power supply circuit.

[0008] The charging control method further includes the following steps: if the bus output voltage is within the third threshold range, performing a proportional-integral operation on the second error value between the target energy storage voltage and the energy storage charging voltage to obtain a second regulated output value; performing a proportional-integral operation on the third error value between the target energy storage current and the energy storage charging current to obtain a third regulated output value; using the smaller of the second regulated output value and the third regulated output value to obtain a third duty cycle; and using the third duty cycle to modulate and generate a first control signal.

[0009] The step of obtaining the third duty cycle using the smaller of the second and third adjustment output values ​​further includes: detecting whether the second duty cycle is less than the third duty cycle; if the second duty cycle is less than the third duty cycle, returning to the step of gradually increasing the minimum duty cycle using the second monotonic function to obtain the second duty cycle.

[0010] The charging control method further includes: if the second duty cycle is not less than the third duty cycle, setting the second duty cycle equal to the third duty cycle.

[0011] The step of detecting whether the bus output voltage is within the third threshold range further includes: detecting whether the bus output voltage is within the third threshold range for a second duration.

[0012] The characteristic electrical parameters also include the turns ratio of the isolation transformer. Before the step of gradually increasing the minimum duty cycle using a second monotonic function to obtain the second duty cycle, the process includes: detecting whether the bus output voltage is greater than the product of the energy storage charging voltage and the turns ratio; if the bus output voltage is not greater than the product of the energy storage charging voltage and the turns ratio, returning to the step of detecting whether the power input is within the first threshold range. If the bus output voltage is greater than the product of the energy storage charging voltage and the turns ratio, the step of gradually increasing the minimum duty cycle using a second monotonic function to obtain the second duty cycle is executed.

[0013] To solve the above-mentioned technical problems, another technical solution adopted in this application is: to provide a charging control circuit, wherein the charging control circuit is used to couple with a power conditioning circuit; wherein the charging control circuit uses the charging control method described in any of the above claims to implement charging control of the power conditioning circuit.

[0014] To solve the above-mentioned technical problems, another technical solution adopted in this application is: to provide an electronic device, wherein the electronic device includes a housing and a charging control circuit connected to the housing; wherein the charging control circuit is the charging control circuit as described above.

[0015] The beneficial effects of this application are as follows: Unlike the prior art, the charging control method provided by this application obtains the characteristic electrical parameters of the power conditioning circuit, and in the initial stage of confirming that the power input is within the first threshold range, uses the first control signal with the first duty cycle gradually adjusted and increased to drive the resonant isolation transformer circuit, and maintains the voltage conversion circuit in the initial wave-blocking state. This can effectively prevent possible fault current and starting inrush current from being directly conducted to the energy storage power supply, and form electrical isolation between the DC power supply and the energy storage power supply, so as to effectively ensure the safety of personnel and equipment during energy storage charging. Furthermore, when the first duty cycle is determined to be not less than the set duty cycle, the first error value between the target bus voltage and the bus output voltage is calculated using proportional-integral operation to obtain the first regulated output value. The second control signal generated by modulating the first regulated output value is then used to drive the voltage conversion circuit. That is, by using clear and detectable electrical parameters as the state judgment to determine the switching conditions, the fixed delay is replaced. The open-loop control of the resonant isolation transformer circuit is transitioned to the closed-loop control of the bus output voltage. This allows the power input of the power conditioning circuit to be established smoothly, and the power conditioning circuit can be dynamically adjusted and controlled according to its initial state or real-time state during operation. This enables the startup process to automatically adapt to different hardware parameters and operating conditions, avoiding voltage and current surges that may be caused by directly starting the control of the voltage conversion circuit under no-load or light-load conditions. This effectively improves the reliability and stability of energy storage charging. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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, wherein: Figure 1 This is a flowchart illustrating the first embodiment of the charging control method of this application; Figure 2 This is a schematic diagram of the first embodiment of the charging control circuit and power regulation circuit of this application; Figure 3 This is a flowchart illustrating the second embodiment of the charging control method of this application; Figure 4 This is a flowchart illustrating the third embodiment of the charging control method of this application; Figure 5 This is a schematic diagram of one embodiment of the electronic device of this application. Detailed Implementation

[0017] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. 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.

[0018] The terms "first," "second," and "third" in this application 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. Therefore, a feature defined as "first," "second," or "third" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. All directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movements between components in a specific orientation (as shown in the figures). If the specific orientation changes, the directional indications also change accordingly. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or devices.

[0019] In this document, the term "implementation" means that a specific feature, structure, or characteristic described in connection with an implementation may be included in at least one implementation of this application. The appearance of this phrase in various places in the specification does not necessarily refer to the same implementation, nor is it a separate or alternative implementation mutually exclusive with other implementations. It will be explicitly and implicitly understood by those skilled in the art that the implementations described herein can be combined with other implementations.

[0020] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] Please refer to the following: Figure 1 and Figure 2 ,in, Figure 1 This is a flowchart illustrating the first embodiment of the charging control method of this application. Figure 2 This is a schematic diagram of the first embodiment of the charging control circuit of this application. Specifically, it may include the following steps: S11 acquires the characteristic electrical parameters of the power conditioning circuit.

[0022] It is understood that the charging control method in this embodiment is specifically applied to, for example... Figure 2 The first charging control circuit 20 shown implements charging control for the power conditioning circuit 30; wherein, the first charging control circuit 20 is used to couple with the power conditioning circuit 30 to implement charging control for the power conditioning circuit 30 using any of the charging control methods described herein.

[0023] Specifically, the power regulation circuit 30 further includes a voltage conversion circuit 31 and a resonant isolation transformer circuit 32. The resonant isolation transformer circuit 32 includes a primary resonant switch sub-circuit 321, an isolation transformer 322, and a secondary switch sub-circuit 323. The voltage conversion circuit 31 is coupled to the primary resonant switch sub-circuit 321 and is used to couple with the DC power supply 101. The isolation transformer 322 is coupled to the primary resonant switch sub-circuit 321 and the secondary switch sub-circuit 323. The secondary switch sub-circuit 323 is used to couple with the energy storage power supply circuit 102.

[0024] In some embodiments, the first charging control circuit 20 may specifically include any reasonable circuit unit with signal processing function, such as a control chip, a DSP (Digital Signal Processing) chip, an MCU (Micro Controller Unit) circuit, a CPU (Central Processing Unit), a microcontroller, a field-programmable gate array, a programmable logic device, discrete gate or transistor logic devices, or discrete hardware. This application does not limit this.

[0025] In some embodiments, the voltage conversion circuit 31 specifically includes any reasonable functional circuit for implementing voltage conversion, such as a Boost converter or a Buck converter, and this embodiment does not limit this.

[0026] In some embodiments, the primary-side resonant switch sub-circuit 321 may specifically include a half-bridge LLC (inductance; capacitor; including an additional inductor L, connected in series with the other two components, inductor L and capacitor C) converter, a full-bridge LLC converter, a full-bridge inverter circuit, a half-bridge inverter circuit, or other forms of LLC circuit topology, and this embodiment does not limit it in this way.

[0027] In some embodiments, the secondary-side switch circuit 323 may specifically include any reasonable rectification function circuit such as a full-bridge rectifier circuit or a half-bridge rectifier circuit, and this embodiment does not limit it.

[0028] In some embodiments, the DC power supply 101 may be any reasonable power supply with DC output, such as a photovoltaic power supply, an independent generator power supply, or a wind turbine power supply, or a power supply circuit that adjusts and transforms the AC or DC power supply 101 to obtain DC output. This embodiment does not limit this.

[0029] In some embodiments, the energy storage power circuit 102 may specifically include one or more of any reasonable energy storage components such as lithium batteries and supercapacitors, and this embodiment does not limit this.

[0030] It is worth noting that the voltage conversion circuit 31 is used to receive the power input Pin provided by the DC power supply 101, and is controlled by the drive control of the first charging control circuit 20 to adjust and transform the power input Pin to obtain the bus output voltage Vbus / bus output current; the resonant isolation transformer circuit 32 is used to receive the bus output voltage Vbus / bus output current, and is controlled by the drive control of the first charging control circuit 20 to perform any reasonable adjustment and transformation of the bus output voltage Vbus / bus output current such as inversion, resonance, isolation, rectification, etc., to charge or discharge the energy storage power supply circuit 102.

[0031] Furthermore, the term "coupled" in this document refers to any direct or indirect connection. Therefore, if the document describes a first circuit coupled to a second circuit, it means that the first circuit can be directly connected to the second circuit via electrical connection or signal connection methods such as wireless transmission or optical transmission, or indirectly connected to the second circuit via other circuits or connection methods via electrical connection or signal connection.

[0032] Specifically, the first charging control circuit 20 is used to sample and obtain characteristic electrical parameters from the power conditioning circuit 30 in real time, or to sample and obtain the characteristic electrical parameters from the first power conditioning circuit 30 in each set sampling period.

[0033] In some embodiments, the characteristic electrical parameters may specifically include the power input Pin and the bus output voltage Vbus in the voltage conversion circuit 31; the power input Pin may specifically include the input current Ipv and / or the input voltage Vpv, which is not limited in this application.

[0034] In some embodiments, the first charging control circuit 20 may specifically sample the power input Pin and the bus output voltage Vbus through one or more of any reasonable sampling circuit or sampling method such as a voltage / current sensor, a sampling resistor, a Hall sensor, or circuit model estimation. This application does not limit this.

[0035] S12: Detect whether the power input is within the first threshold range.

[0036] Understandably, taking the DC power supply 101 as a photovoltaic power supply as an example, the output voltage of the photovoltaic power supply will have different amplitude states at different times. For example, in the morning, evening or on cloudy days, its output voltage is usually lower and may not be able to meet the minimum voltage required for charging the energy storage power circuit 102. This causes the power regulation circuit 30 to fail to work normally during some periods. Therefore, before starting the control and regulation of the power regulation circuit 30, it is necessary to fit and set a first threshold range according to the charging requirements of the energy storage power circuit 102 and the normal operation requirements of the power regulation circuit 30, so as to determine whether the current power input pin of the DC power supply 101 meets the specific start-up conditions.

[0037] Specifically, it detects whether the currently acquired power input pin, such as the input current Ipv and / or the input voltage Vpv, is within a first threshold range.

[0038] If the power input pin is not within the first threshold range, then S13 is executed; if the power input pin is within the first threshold range, then S14 is executed.

[0039] S13: Enter the initial state.

[0040] If the power input pin is determined to be outside the first threshold range, the first charging control circuit 20 remains in the initial blocking state, that is, it does not perform wave generation control on the power conditioning circuit 30, so that the power conditioning circuit 30 is kept in the initial disabled state, thereby reducing circuit loss.

[0041] It is worth noting that the power input pin specifically includes the input current Ipv and the input voltage Vpv. The first threshold range includes the current threshold range and the voltage threshold range. When the input current Ipv is not within the current threshold range and / or the input voltage Vpv is not within the voltage threshold range, the initial state is entered. S14 is only executed when the input current Ipv is within the current threshold range and the input voltage Vpv is also within the voltage threshold range.

[0042] S14: The first duty cycle is obtained by gradually increasing the minimum duty cycle using the first monotonic function.

[0043] When it is determined that the currently acquired power input pin is within the first threshold range, the minimum duty cycle is calculated and processed using a first monotonic function or a preset rule program in each first switching cycle, so as to gradually adjust and increase the minimum duty cycle to obtain the first duty cycle.

[0044] It is worth noting that this minimum duty cycle is specifically the minimum value that the duty cycle set by the physical characteristics of the switching element and the corresponding control program can achieve.

[0045] In addition, the duty cycle generally refers to the pulse duty cycle, which is the proportion of the high level in one pulse cycle. The formula is the ratio of the on-time to the total period. When the frequency is constant, the voltage can be adjusted by adjusting this ratio. For example, a 5V square wave signal with a duty cycle of 80% can be equivalent to a 4V voltage.

[0046] In some embodiments, the first monotonic function may be any reasonable monotonic function such as a linear monotonic function, an arithmetic monotonic function, or an exponential monotonic function, and this application does not limit it in this regard.

[0047] S15: Generate a first control signal by modulating with the first duty cycle.

[0048] Once the first duty cycle is obtained, the ratio of high to low pulse levels can be determined to generate the first control signal.

[0049] In some embodiments, the first control signal and other control signals herein may be one or more of any reasonable control signals such as PWM (Pulse Width Modulation) signal or PFM (Pulse Frequency Modulation) signal, and this application does not limit them.

[0050] S16: Send the first control signal to the resonant isolation transformer circuit to trigger the resonant isolation transformer circuit to change the switching state.

[0051] The first charging control circuit 20 sends the first control signal obtained by modulation to the primary side resonant switch sub-circuit 321 in the resonant isolation transformer circuit 32, so as to drive and control the switching state of the primary side resonant switch sub-circuit 321 by the first control signal with gradually increasing first duty cycle in the initial stage, thereby avoiding overcurrent in the resonant cavity or excessive stress on the switching tube due to sudden change in duty cycle.

[0052] S17: Detect whether the first duty cycle is less than the set duty cycle.

[0053] During the first switching cycle of each first control signal, it is detected whether the currently acquired first duty cycle is less than the set duty cycle.

[0054] Understandably, this duty cycle setting is the upper limit of the duty cycle set when the primary resonant switch sub-circuit 321 enters steady-state operation or during its independent soft-start phase.

[0055] If the first duty cycle is not less than the set duty cycle, then S18 is executed; if the first duty cycle is less than the set duty cycle, then S14 is executed.

[0056] S18: Set the first duty cycle to the set duty cycle.

[0057] When it is determined that the first duty cycle is not less than the set duty cycle, the first duty cycle is set to be equal to the set duty cycle, that is, the first duty cycle limit of the first control signal is within the range of not greater than the set duty cycle.

[0058] It is worth noting that the process of gradually increasing the first duty cycle from the minimum duty cycle to the set duty cycle can be defined as the soft-start stage of the primary resonant switch sub-circuit 321. During this soft-start stage, the first charging control circuit 20 will not perform wave generation control on the voltage conversion circuit 31 and the secondary switch sub-circuit 323, so that the voltage conversion circuit 31 and the secondary switch sub-circuit 323 are kept in the initial disabled state. This avoids the inrush current that may be generated during the soft-start stage being output to the energy storage power circuit 102 through the voltage conversion circuit 31 and the secondary switch sub-circuit 323, which could damage the energy storage power circuit 102.

[0059] S19: Perform a proportional-integral calculation on the first error value between the target bus voltage and the bus output voltage to obtain the first regulated output value.

[0060] To ensure that the drive control of the voltage conversion circuit 31, i.e. the feedback adjustment of the bus output voltage Vbus, does not deviate from a specific threshold range, and to meet the control requirements of the voltage conversion circuit 31 and the charging requirements of the energy storage power circuit 102, a target bus voltage is fitted and set, i.e., as the target value that the bus output voltage Vbus is adjusted to approach.

[0061] Furthermore, the target bus voltage is subtracted from the currently acquired bus output voltage Vbus to obtain a first error value. The first error value is then proportionally integrated using the internal voltage loop or a preset control algorithm and program operation rules to obtain a first regulated output value.

[0062] S110: The second control signal is generated by modulating the first adjustment output value.

[0063] The first regulated output value is processed by a set signal modulation rule to obtain a second control signal. The characteristic parameters of the second control signal, such as duty cycle and / or signal frequency, are dynamically adjusted in real time to make the bus output voltage Vbus gradually approach the target bus voltage, so that the bus output voltage Vbus smoothly follows the voltage rise of the power input Pin, while avoiding the input current Ipv surge.

[0064] S111: Send the second control signal to the voltage conversion circuit to trigger the voltage conversion circuit to change the switching state, thereby adjusting the bus output voltage.

[0065] The second control signal obtained by modulation is sent to the voltage conversion circuit 31 to trigger the switching element inside the voltage conversion circuit 31 to turn on or off, thereby regulating the bus output voltage Vbus of the voltage conversion circuit 31.

[0066] It is worth noting that during the closed-loop feedback stage of the voltage conversion circuit 31, the first charging control circuit 20 will remain in a state of blocking and disabling the secondary switch sub-circuit 323 to prevent the inrush current that may be generated during this stage from being output to the energy storage power circuit 102 through the secondary switch sub-circuit 323 and causing damage to the energy storage power circuit 102.

[0067] The above scheme, by using a first control signal with a gradually increasing first duty cycle to drive and control the primary resonant switch sub-circuit 321 of the isolation transformer 322 during the initial stage when the power input pin is within the first threshold range, and maintaining the voltage conversion circuit 31 in the initial blocking state, can effectively prevent possible fault current and starting inrush current from being directly conducted to the energy storage power supply, and form electrical isolation between the DC power supply 101 and the energy storage power supply, so as to effectively ensure the safety of personnel and equipment during energy storage charging. Furthermore, by using clear and detectable electrical parameters as the state judgment to determine the switching conditions instead of a fixed delay, the open-loop control of the primary resonant switch sub-circuit 321 is transitioned to a closed-loop feedback control of the bus output voltage Vbus. This allows the power input pin of the power conditioning circuit 30 to be established smoothly, and the power conditioning circuit 30 can be dynamically adjusted and controlled according to its initial state or real-time state during operation. This enables the startup process to automatically adapt to different hardware parameters and operating conditions, avoiding voltage and current surges that may be caused by directly starting the control of the voltage conversion circuit 31 under no-load or light-load conditions. This effectively improves the reliability and stability of energy storage charging.

[0068] Please see Figure 3 , Figure 3 This is a flowchart illustrating the second embodiment of the charging control method of this application. The charging control method of this embodiment... Figure 1 A detailed implementation diagram of the charging control method is shown, which specifically includes the following steps: S41: Obtain the characteristic electrical parameters of the power supply regulation circuit.

[0069] S42: Detect whether the power input is within the first threshold range.

[0070] S43: Enter the initial state.

[0071] S44: The first duty cycle is obtained by gradually increasing the minimum duty cycle using the first monotonic function.

[0072] S45: Generate a first control signal by modulating with the first duty cycle.

[0073] S46: Send the first control signal to the resonant isolation transformer circuit to trigger the resonant isolation transformer circuit to change the switching state.

[0074] S47: Detect whether the first duty cycle is less than the set duty cycle.

[0075] S48: Set the first duty cycle to the set duty cycle.

[0076] S49: Perform a proportional-integral calculation on the first error value between the target bus voltage and the bus output voltage to obtain the first regulated output value.

[0077] S410: The second control signal is generated by modulating the first regulation output value.

[0078] S411: Send the second control signal to the voltage conversion circuit to trigger the voltage conversion circuit to change the switching state, thereby adjusting the bus output voltage.

[0079] Among them, S41, S42, S43, S44, S45, S46, S47, S48, S49, S410, and S411 and Figure 1 S11, S12, S13, S14, S15, S16, S17, S18, S19, S110, and S111 are the same. For details, please refer to the textual descriptions of S11, S12, S13, S14, S15, S16, S17, S18, S19, S110, and S111, and they will not be repeated here.

[0080] S412: Detect whether the power input is within the second threshold range for a first duration.

[0081] Understandably, before enabling the secondary switch circuit 323 to charge the energy storage power circuit 102, it is necessary to ensure that the power input Pin and the bus output voltage Vbus are stable within the expected threshold range, so as to avoid damage to the energy storage power circuit 102 by possible inrush current and to ensure that charging can be effectively achieved.

[0082] Specifically, after implementing closed-loop feedback regulation on the voltage conversion circuit 31, the power input pin is detected, such as whether the input current Ipv and / or the input voltage Vpv remain within the second threshold range for a first duration.

[0083] In some embodiments, the first duration can be any reasonable duration, such as 5 seconds, 20 seconds, or 60 seconds, representing a limited duration during which the power input pin has continuous input and can be charged. This application does not limit this duration.

[0084] In some embodiments, the power input pin may specifically include an input current Ipv, and the second threshold range corresponds to any reasonable current range such as a current greater than 0, 0.01A (amperes), or 0.1A. This application does not limit this range.

[0085] If the power input pin is within the second threshold range and lasts for a first duration, then S413 is executed; if the power input pin is not within the second threshold range, or the duration of the power input pin within the second threshold range is less than the first duration, then S48 is executed.

[0086] S413: Detect whether the bus output voltage is within the third threshold range.

[0087] After determining that the power input pin is within the second threshold range and maintaining this for a first duration, the bus output voltage Vbus is further detected to see if it is within the third threshold range.

[0088] It is worth noting that the third threshold range can be specifically understood as the expected MPPT (Maximum Power Point Tracking) voltage range for controlling the voltage conversion circuit 31.

[0089] If the bus output voltage Vbus is within the third threshold range, then S414 and S417 are executed synchronously; if the bus output voltage Vbus is not within the third threshold range, then S48 is executed again.

[0090] S414: The second duty cycle is obtained by gradually increasing the minimum duty cycle using the second monotonic function.

[0091] When the bus output voltage Vbus is determined to be within the third threshold range, the energy storage power supply circuit 102 can enter the normal charging state, so that the minimum duty cycle is calculated and processed by the second monotonic function or the preset rule program in each third switching cycle, thereby gradually adjusting and increasing the minimum duty cycle to obtain the second duty cycle.

[0092] In some embodiments, the second monotonic function may be any reasonable monotonic function such as a linear monotonic function, an arithmetic monotonic function, or an exponential monotonic function, and this application does not limit it in this regard.

[0093] S415: Generates a third control signal by modulating with the second duty cycle.

[0094] Once the second duty cycle is obtained, the ratio of the high and low pulse levels can be determined to modulate and generate the third control signal.

[0095] S416: Sends the third control signal to the secondary switch sub-circuit to trigger the secondary switch sub-circuit to change the switching state, thereby regulating the charging and discharging of the energy storage power supply circuit.

[0096] The third control signal obtained by modulation is sent to the secondary switch sub-circuit 323 to trigger the switching element inside the secondary switch sub-circuit 323 to turn on or off, thereby regulating the charging and discharging of the energy storage power circuit 102. The second duty cycle of the third control signal is gradually increased in each third switching cycle to stabilize and establish the expected charging voltage.

[0097] S417: Perform a proportional-integral calculation on the second error value between the target energy storage voltage and the energy storage charging voltage to obtain the second regulated output value.

[0098] Understandably, when it is determined that the bus output voltage Vbus is within the third threshold range and the energy storage power supply circuit 102 can enter the normal charging state, the open-loop control of the primary side resonant switch sub-circuit 321 needs to be adjusted to closed-loop feedback control in order to follow the changes in the bus output voltage Vbus.

[0099] Specifically, the electrical parameters include the energy storage charging voltage Vbat and the energy storage charging current Ibat in the secondary-side switching sub-circuit 323. To ensure that the drive control of the primary-side resonant switching sub-circuit 321 does not deviate from a specific threshold range and to meet the charging requirements of the energy storage power supply circuit 102, a target energy storage voltage is fitted and set, which is used as the target value for adjusting the energy storage charging voltage Vbat.

[0100] Specifically, the target energy storage voltage is subtracted from the currently acquired energy storage charging voltage Vbat to obtain a second error value. The second error value is then subjected to proportional-integral calculation through its internal voltage loop or preset control algorithm and program operation rules to obtain a second regulated output value.

[0101] S418: Perform proportional-integral calculation on the third error value between the target energy storage current and the energy storage charging current to obtain the third regulated output value.

[0102] Similarly, in order to meet the charging requirements of the energy storage power circuit 102, a target energy storage current is fitted and set, which is used as the target value of the energy storage charging current Ibat. The target energy storage current is subtracted from the currently acquired energy storage charging current Ibat to obtain the third error value. The third adjustment output value is obtained by proportional integration calculation of the third error value through its internal current loop or preset control algorithm and program operation rules.

[0103] S419: The third duty cycle is obtained by using the smaller of the second and third adjustable output values.

[0104] The second and third adjustment output values ​​are compared to select the smaller one. If the second adjustment output value is less than the third adjustment output value, the second adjustment output value is processed to obtain the third duty cycle; if the second adjustment output value is greater than the third adjustment output value, the third adjustment output value is processed to obtain the third duty cycle.

[0105] S420: Generates the first control signal by modulating with the third duty cycle.

[0106] In the initial stage of the energy storage power circuit 102 entering the normal charging state, the open-loop control of the primary resonant switch sub-circuit 321 is adjusted to closed-loop feedback control. That is, when the third duty cycle is obtained, the third duty cycle is used to replace the first duty cycle to generate a first control signal, and then the first control signal with the third duty cycle is sent to the primary resonant switch sub-circuit 321 to achieve drive control of the primary resonant switch sub-circuit 321.

[0107] S421: Detect whether the second duty cycle is less than the third duty cycle.

[0108] Furthermore, in order to ensure the stable establishment of the energy storage charging voltage Vbat and the energy storage charging current Ibat, after the second duty cycle is gradually increased to achieve soft start, it is also necessary to ensure that the switching elements in the secondary-side switching sub-circuit 323 can follow the duty cycle changes of the switching elements in the primary-side resonant switching sub-circuit 321.

[0109] Specifically, it detects whether the second duty cycle of the current third signal cycle is less than the third duty cycle.

[0110] If the second duty cycle is less than the third duty cycle, then return to execute S414; if the second duty cycle is not less than the third duty cycle, then execute S422.

[0111] S422: Set the second duty cycle to equal the third duty cycle.

[0112] When it is determined that the second duty cycle is not less than the third duty cycle, the second duty cycle can be made to follow the change of the third duty cycle, that is, the second duty cycle can be made equal to the third duty cycle.

[0113] For ease of understanding, let's take the process of the first charging control circuit 20 driving the power regulation circuit 30 as an example, divided into four stages. In the first stage, the first charging control circuit 20 specifically uses the power input Pin being within a first threshold range as the initial trigger condition. It first implements open-loop control on the primary-side resonant switch sub-circuit 321, which can be understood as the soft-start stage of the resonant isolation transformer primary side. The first duty cycle is not less than the set duty cycle as the termination condition of the first stage, entering the second stage. In the second stage, the open-loop control of the primary-side resonant switch sub-circuit 321 is maintained, and the voltage conversion circuit 31 is simultaneously implemented with closed-loop feedback control, which can be understood as the Boost intervention stage. The power input Pin is continuously within a second threshold range for a first duration. Within the threshold range, and with the bus output voltage Vbus within the third threshold range, the second stage terminates and enters the third stage. In the third stage, the open-loop control of the primary resonant switch sub-circuit 321 is switched to closed-loop feedback control, while maintaining closed-loop feedback control of the voltage conversion circuit 31. At the same time, open-loop control is implemented for the secondary switch sub-circuit 323, which can be understood as the synchronous rectification intervention stage of the secondary side of the resonant isolation transformer. The second duty cycle is not less than the third duty cycle as the termination condition of the third stage, and the fourth stage begins. In the fourth stage, the secondary switch sub-circuit 323 follows the primary resonant switch sub-circuit 321 to implement closed-loop feedback control, while maintaining closed-loop feedback control of the voltage conversion circuit 31. The expected charging voltage has been stably established.

[0114] The above scheme replaces "fixed delay" with "state judgment": the startup process is clearly divided into multiple stages, and clear and detectable electrical parameters are defined for the end and switching of each stage as the basis for judgment, so that the control process gradually changes from open loop to closed loop, effectively ensuring the safety and reliability of charging startup. Through "adaptive timing" logic: key control parameters (such as soft start time, synchronous rectifier duty cycle and timing, etc.) can be dynamically adjusted according to the initial state of the system (such as the voltage and / or current of the power input pin) or the real-time state during operation, so that the startup process can automatically adapt to different hardware parameters and operating conditions. Through the Boost pre-start mode of "bus output voltage Vbus following": before the voltage conversion circuit 31 officially executes MPPT, a transitional "bus voltage following" control mode, i.e., voltage feedback regulation, is introduced to make the input current Ipv of DC power supply 101 build up smoothly, completely avoiding the voltage and current shocks that may be caused by directly starting MPPT on the no-load or light-load bus.

[0115] Furthermore, in some embodiments, the above-mentioned S413 may further include: detecting whether the bus output voltage Vbus remains within a third threshold range for a second duration.

[0116] Understandably, in order to ensure the smooth establishment of the expected charging voltage, the termination condition of the second stage can also be that the power input pin remains within the second threshold range for a first duration, and the bus output voltage Vbus remains within the third threshold range for a second duration.

[0117] In some embodiments, the second duration can be any reasonable duration, such as 5 seconds, 20 seconds, or 60 seconds, representing a time limit during which the bus output voltage Vbus stabilizes near the expected MPPT voltage. This application does not limit this duration.

[0118] Please see Figure 4 , Figure 4 This is a flowchart illustrating the third embodiment of the charging control method of this application. The charging control method of this embodiment... Figure 3 A detailed implementation diagram of the charging control method is shown, which specifically includes the following steps: S51: Obtain the characteristic electrical parameters of the power supply regulation circuit.

[0119] S52: Detect whether the power input is within the first threshold range.

[0120] S53: Enter the initial state.

[0121] S54: The first duty cycle is obtained by gradually increasing the minimum duty cycle using the first monotonic function.

[0122] S55: Generate a first control signal by modulating with the first duty cycle.

[0123] S56: Send the first control signal to the resonant isolation transformer circuit to trigger the resonant isolation transformer circuit to change the switching state.

[0124] S57: Detect whether the first duty cycle is less than the set duty cycle.

[0125] S58: Set the first duty cycle to the set duty cycle.

[0126] S59: Perform a proportional-integral calculation on the first error value between the target bus voltage and the bus output voltage to obtain the first regulated output value.

[0127] S510: The second control signal is generated by modulating the first regulation output value.

[0128] S511: Sends the second control signal to the voltage conversion circuit to trigger the voltage conversion circuit to change the switching state, thereby adjusting the bus output voltage.

[0129] S512: Detect whether the power input is within the second threshold range for a first duration.

[0130] S513: Detect whether the bus output voltage is within the third threshold range.

[0131] Among them, S51, S52, S53, S54, S55, S56, S57, S58, S59, S510, S511, S512 and S513 and Figure 3 S41, S42, S43, S44, S45, S46, S47, S48, S49, S410, S411, S412, and S413 are the same. For details, please refer to the descriptions of S41, S42, S43, S44, S45, S46, S47, S48, S49, S410, S411, S412, and S413 and their related texts. They will not be repeated here.

[0132] S514: Detect whether the bus output voltage is greater than the product of the energy storage charging voltage and the turns ratio.

[0133] Understandably, in order to ensure that the charging of the energy storage power circuit 102 can be started smoothly, that is, the energy storage power circuit 102 can absorb energy from the power regulation circuit 30, before enabling the secondary switch sub-circuit 323, it is necessary to determine whether the voltage referred to the secondary side is greater than the currently sampled energy storage charging voltage Vbat, so as to ensure that energy can flow from the power regulation circuit 30 into the energy storage power circuit 102.

[0134] Specifically, the characteristic electrical parameter also includes the turns ratio N of the isolation transformer 322, and the first charging control circuit 20 is also used to detect whether the bus output voltage Vbus is greater than the product of the energy storage charging voltage Vbat and the turns ratio N.

[0135] If the bus output voltage Vbus is greater than the product of the energy storage charging voltage Vbat and the turns ratio N, i.e., Vbus>Vbat*N, then execute S515; if the bus output voltage Vbus is not greater than the product of the energy storage charging voltage Vbat and the turns ratio N, then return to execute S59.

[0136] S515: The second duty cycle is obtained by gradually increasing the minimum duty cycle using the second monotonic function.

[0137] S516: Generates a third control signal by modulating with the second duty cycle.

[0138] S517: Sends the third control signal to the secondary switch sub-circuit to trigger the secondary switch sub-circuit to change the switching state, thereby regulating the charging and discharging of the energy storage power supply circuit.

[0139] S518: Perform proportional-integral calculation on the second error value between the target energy storage voltage and the energy storage charging voltage to obtain the second regulated output value.

[0140] S519: Perform proportional-integral calculation on the third error value between the target energy storage current and the energy storage charging current to obtain the third regulated output value.

[0141] S520: The third duty cycle is obtained by using the smaller of the second and third adjustment output values.

[0142] S521: Generate the first control signal by modulating with the third duty cycle.

[0143] S522: Detect whether the second duty cycle is less than the third duty cycle.

[0144] S523: Set the second duty cycle to equal the third duty cycle.

[0145] Among them, S515, S516, S517, S518, S519, S520, S521, S522 and S523 and Figure 3 S414, S415, S416, S417, S418, S419, S420, S421, and S422 are the same. For details, please refer to S414, S415, S416, S417, S418, S419, S420, S421, and S422 and their related textual descriptions. They will not be repeated here.

[0146] This application also provides an electronic device, please refer to... Figure 5 , Figure 5 This is a schematic diagram of one embodiment of the electronic device of this application. In this embodiment, the electronic device 60 includes a housing 61 and a second charging control circuit 62 connected to the housing 61.

[0147] It should be noted that the second charging control circuit 62 described in this embodiment is the first charging control circuit 20 described in any of the above embodiments. Please refer to [link / reference] for details. Figures 1-4 The relevant textual content will not be elaborated upon here.

[0148] The beneficial effects of this application are as follows: Unlike the prior art, the charging control method provided by this application obtains the characteristic electrical parameters of the power conditioning circuit, and in the initial stage of confirming that the power input is within the first threshold range, uses the first control signal with the first duty cycle gradually adjusted and increased to drive the resonant isolation transformer circuit, and maintains the voltage conversion circuit in the initial wave-blocking state. This can effectively prevent possible fault current and starting inrush current from being directly conducted to the energy storage power supply, and form electrical isolation between the DC power supply and the energy storage power supply, so as to effectively ensure the safety of personnel and equipment during energy storage charging. Furthermore, when the first duty cycle is determined to be not less than the set duty cycle, the first error value between the target bus voltage and the bus output voltage is calculated using proportional-integral operation to obtain the first regulated output value. The second control signal generated by modulating the first regulated output value is then used to drive the voltage conversion circuit. That is, by using clear and detectable electrical parameters as the state judgment to determine the switching conditions, the fixed delay is replaced. The open-loop control of the resonant isolation transformer circuit is transitioned to the closed-loop control of the bus output voltage. This allows the power input of the power conditioning circuit to be established smoothly, and the power conditioning circuit can be dynamically adjusted and controlled according to its initial state or real-time state during operation. This enables the startup process to automatically adapt to different hardware parameters and operating conditions, avoiding voltage and current surges that may be caused by directly starting the control of the voltage conversion circuit under no-load or light-load conditions. This effectively improves the reliability and stability of energy storage charging.

[0149] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A charging control method, applied in a power supply regulation circuit, characterized in that, The charging control method includes: Obtain the characteristic electrical parameters of the power conditioning circuit; wherein, the power conditioning circuit includes a voltage conversion circuit and a resonant isolation transformer circuit, the resonant isolation transformer circuit includes a primary resonant switch sub-circuit, an isolation transformer, and a secondary switch sub-circuit, the voltage conversion circuit is coupled to the primary resonant switch sub-circuit and is used to couple with a DC power supply, the isolation transformer is coupled to the primary resonant switch sub-circuit and the secondary switch sub-circuit, the secondary switch sub-circuit is used to couple with an energy storage power supply circuit, and the characteristic electrical parameters include the power input and bus output voltage in the voltage conversion circuit, and the energy storage charging voltage and energy storage charging current in the secondary switch sub-circuit; Detect whether the power input is within the first threshold range; If the power input is within the first threshold range, the first duty cycle is obtained by gradually increasing the minimum duty cycle using a first monotonic function; The first control signal is generated by modulating the first duty cycle. The first control signal is sent to the resonant isolation transformer circuit to trigger the resonant isolation transformer circuit to change its switching state; Detect whether the first duty cycle is less than the set duty cycle; If the first duty cycle is not less than the set duty cycle, set the first duty cycle to be equal to the set duty cycle; A first regulated output value is obtained by performing a proportional-integral calculation on the first error value between the target bus voltage and the bus output voltage; The second control signal is generated by modulating the first adjusted output value. The second control signal is sent to the voltage conversion circuit to trigger the voltage conversion circuit to change the switching state, thereby adjusting the bus output voltage; Detect whether the power input remains within the second threshold range for a first duration; If the power input remains within the second threshold range for the first duration, detect whether the bus output voltage is within the third threshold range. If the bus output voltage is within the range of the third threshold, the second duty cycle is obtained by gradually increasing the minimum duty cycle using the second monotonic function; The third control signal is generated by modulating the second duty cycle. The third control signal is sent to the secondary switch sub-circuit to trigger the secondary switch sub-circuit to change its switching state, thereby regulating the charging and discharging of the energy storage power circuit.

2. The charging control method according to claim 1, characterized in that, The charging control method further includes: If the first duty cycle is less than the set duty cycle, return to the step of gradually increasing the minimum duty cycle using the first monotonic function to obtain the first duty cycle.

3. The charging control method according to claim 1, characterized in that, The charging control method further includes the following steps: If the bus output voltage is within the third threshold range, a second regulated output value is obtained by performing a proportional-integral operation on the second error value between the target energy storage voltage and the energy storage charging voltage. The third adjustment output value is obtained by performing a proportional-integral calculation on the third error value between the target energy storage current and the energy storage charging current; The third duty cycle is obtained by using the smaller of the second and third adjusted output values; The first control signal is generated by modulating with the third duty cycle.

4. The charging control method according to claim 3, characterized in that, After the step of obtaining the third duty cycle using the smaller of the second and third adjusted output values, the method further includes: Detect whether the second duty cycle is less than the third duty cycle; If the second duty cycle is less than the third duty cycle, return to the step of gradually increasing the minimum duty cycle using the second monotonic function to obtain the second duty cycle.

5. The charging control method according to claim 4, characterized in that, The charging control method further includes: If the second duty cycle is not less than the third duty cycle, then set the second duty cycle to be equal to the third duty cycle.

6. The charging control method according to claim 1, characterized in that, The step of detecting whether the bus output voltage is within the third threshold range further includes: The system detects whether the output voltage of the busbar remains within the range of the third threshold for a second duration.

7. The charging control method according to claim 1, characterized in that, The characteristic electrical parameters also include the turns ratio of the isolation transformer. Before the step of gradually adjusting and increasing the minimum duty cycle using a second monotonic function to obtain the second duty cycle, the following steps are also included: Detect whether the bus output voltage is greater than the product of the energy storage charging voltage and the turns ratio; If the bus output voltage is not greater than the product of the energy storage charging voltage and the turns ratio, return to the step of detecting whether the power input is within the first threshold range; If the bus output voltage is greater than the product of the energy storage charging voltage and the turns ratio, the step of gradually increasing the minimum duty cycle using a second monotonic function to obtain the second duty cycle is executed.

8. A charging control circuit, characterized in that, The charging control circuit is used to couple with the power regulation circuit; The charging control circuit uses the charging control method as described in any one of claims 1-7 to implement charging control for the power conditioning circuit.

9. An electronic device, characterized in that, The electronic device includes a housing and a charging control circuit connected to the housing; The charging control circuit is the charging control circuit as described in claim 8.

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