Totem pole circuit control method, totem pole circuit and electronic device

Abstract

The present application discloses a control method of a totem pole circuit, a totem pole circuit and an electronic device, wherein the control method of the totem pole circuit comprises: obtaining an output voltage in a switch subcircuit; obtaining a cycle on time and a second count comparison value using the output voltage; obtaining an input voltage, a preset minimum value of a negative current and a count cycle setting value in an energy storage subcircuit; obtaining a maximum value of an energy storage current in the energy storage subcircuit in response to the cycle on time being greater than the preset on time; obtaining a first count comparison value using the count cycle setting value, the second count comparison value, the maximum value and the minimum value; generating a first control signal using the count cycle setting value, the second count comparison value and the first count comparison value; and adjusting the switch state of the switch subcircuit using the first control signal to adjust the energy storage current and the output voltage. In the above manner, the control method of the totem pole circuit of the present application can effectively improve the conversion efficiency and reduce the waveform distortion rate.

Description

Technical Field

[0001] The present application relates to the field of circuit control technology, and in particular to a control method of a totem pole circuit, a totem pole circuit and an electronic device. Background Art

[0002] As GaN high electron mobility transistor technology becomes increasingly mature, totem pole circuit soft switching related control technology has gradually become the mainstream of high-efficiency power supplies due to its advantages such as high switching frequency and low reverse recovery loss.

[0003] However, due to the high switching frequency in the control of the totem pole circuit, the negative current time is usually controlled together with the dead zone, as a fixed value or input according to multi-stage fitting based on actual measurement of working conditions, resulting in low conversion efficiency. Summary of the invention

[0004] The main technical problem solved by the present application is to provide a control method for a totem pole circuit, a totem pole circuit and an electronic device, which can solve the problem that the control method of the totem pole circuit in the prior art controls the negative current time and the dead zone synchronously, and inputs them as a fixed value or according to the actual measurement of multiple stages of working conditions, resulting in low conversion efficiency.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a control method of a totem pole circuit, the totem pole circuit includes an energy storage subcircuit and a switch subcircuit, the energy storage subcircuit is coupled to the switch subcircuit, and is used to couple with a power supply circuit, wherein the control method of the totem pole circuit includes: obtaining the output voltage in the switch subcircuit; obtaining the cycle on time by using the output voltage; obtaining the input voltage, the minimum value of the preset negative current and the counting cycle setting value in the energy storage subcircuit; in response to the cycle on time being greater than the preset on time, obtaining the maximum value and the operation count comparison value of the energy storage current in the energy storage subcircuit; obtaining the first count comparison value by using the counting cycle setting value, the operation count comparison value, the maximum value and the minimum value; obtaining the second count comparison value by using the first count comparison value and the cycle on time; generating a first control signal by using the counting cycle setting value, the first count comparison value and the second count comparison value; wherein the operation count comparison value is the second count comparison value of the previous signal cycle of the first control signal; and adjusting the switching state of the switch subcircuit by using the first control signal to adjust the energy storage current and the output voltage.

[0006] Among them, the step of obtaining the input voltage in the power supply circuit, the minimum value of the preset negative current and the counting cycle setting value also includes: multiplying the input voltage by the preset load factor to obtain the minimum value.

[0007] Among them, the step of obtaining the input voltage in the power supply circuit, the minimum value of the preset negative current and the counting cycle setting value also includes: obtaining the counting cycle value when the energy storage current passes through zero to obtain the counting cycle setting value.

[0008] The step of obtaining the maximum value of the energy storage current in the energy storage subcircuit includes: dividing the input voltage by the equivalent inductance value of the energy storage subcircuit, and multiplying by the cycle opening time to obtain the maximum value.

[0009] The step of obtaining the first counting comparison value by using the counting cycle setting value, the calculated counting comparison value, the maximum value and the minimum value includes: multiplying the difference between the counting cycle setting value and the calculated counting comparison value by the maximum value and dividing by the minimum value to obtain the first counting comparison value.

[0010] Among them, in response to the cycle turn-on time being greater than the preset turn-on time, before the step of obtaining the maximum value of the energy storage current in the energy storage sub-circuit and the operation count comparison value, it also includes: using the blanking window to limit the maximum frequency to obtain the initial turn-on time; multiplying the initial turn-on time by the set proportional coefficient to obtain the preset turn-on time.

[0011] Wherein, in response to the cycle on-time being greater than the preset on-time, before the step of obtaining the maximum value of the energy storage current in the energy storage subcircuit, it also includes: obtaining the preset on-time by using the preset switching frequency.

[0012] Among them, the control method of the totem pole circuit also includes: in response to the cycle opening time being not greater than the preset opening time, using the output voltage to obtain the per-unit coefficient; subtracting the input voltage from the output voltage to obtain the voltage difference; subtracting the minimum value from the zero current to obtain the current difference; multiplying the equivalent inductance value of the energy storage subcircuit by the product of the current difference and dividing by the voltage difference, and multiplying by the per-unit coefficient to obtain a third counting comparison value; using the third counting comparison value and the cycle opening time to obtain a fourth counting comparison value; using the counting cycle setting value, the third counting comparison value and the fourth counting comparison value to generate a second control signal; using the second control signal to adjust the switching state of the switch subcircuit to adjust the energy storage current and the output voltage.

[0013] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a totem pole circuit, wherein the totem pole circuit includes an energy storage sub-circuit, a switch sub-circuit and a control sub-circuit, the energy storage sub-circuit is coupled to the switch sub-circuit and is used to couple with the power supply circuit, and the control sub-circuit is coupled to the energy storage sub-circuit and the switch sub-circuit; wherein the control sub-circuit is coupled to the switch sub-circuit so as to control the switch sub-circuit by adopting the control method of the totem pole circuit described in any of the above items.

[0014] In order to solve the above technical problems, another technical solution adopted by the present application is: to provide an electronic device, wherein the electronic device includes a shell and a totem pole circuit connected to the shell; wherein the totem pole circuit is the totem pole circuit as described above.

[0015] The beneficial effect of the present application is as follows: Different from the prior art, the control method of the totem pole circuit provided by the present application obtains the output voltage in the switch subcircuit, obtains the cycle opening time and the second counting comparison value by using the output voltage, and obtains the input voltage, the counting cycle setting value and the preset value of the adaptive negative current, that is, the minimum value of the preset negative current, in the energy storage subcircuit, so as to obtain the current peak value of the energy storage current in the energy storage subcircuit when the cycle opening time is greater than the preset opening time, that is, the maximum value of the energy storage current, so as to obtain the first counting comparison value by using the counting cycle setting value, the second counting comparison value, the maximum value of the energy storage current and the minimum value of the preset negative current, and then generate the first control signal by using the counting cycle setting value, the second counting comparison value and the first counting comparison value, and adjust the switching state of the switch subcircuit by using the first control signal to adjust the energy storage current and the output voltage, so as to be able to adapt to the preset value of the negative current and the peak value change of the energy storage current, effectively improve the conversion efficiency of the totem pole circuit in different periods, reduce the waveform distortion of the electrical signal, so as to reduce the switching loss, and also define the negative current according to the actual situation. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0017] Figure 1 It is a flowchart of a first implementation method of a control method of a totem pole circuit of the present application;

[0018] Figure 2 It is a structural schematic diagram of a first implementation mode of a totem pole circuit of the present application;

[0019] Figure 3 It is a structural schematic diagram of a specific embodiment of the totem pole circuit of the present application;

[0020] Figure 4 It is the control block diagram of the totem pole circuit in the triangle current mode;

[0021] Figure 5 It is a waveform timing diagram of each signal in the totem pole circuit under the triangular current mode;

[0022] Figure 6is a schematic structural diagram of an embodiment of an adaptive negative current;

[0023] Figure 7 yes Figure 1 A schematic diagram of the waveform timing of each signal in the control method of the totem pole circuit;

[0024] Figure 8 It is a schematic structural diagram of an embodiment of an electronic device of the present application. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0026] The terms "first", "second" and "third" in this application are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the implementation mode of this application are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. 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 optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0027] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0028] The present application is described in detail below with reference to the accompanying drawings and implementation methods.

[0029] Please refer to Figure 1 and Figure 2 ,in, Figure 1 is a flow chart of a first embodiment of a control method of a totem pole circuit of the present application, Figure 2 This is a schematic diagram of the structure of the first embodiment of the totem pole circuit of the present application. Specifically, it may include the following steps:

[0030] S11: Obtain the output voltage in the switch subcircuit.

[0031] It is understandable that the control method of the totem pole circuit in this embodiment is specifically applied to the following Figure 2 The totem pole circuit 20 shown in the figure includes an energy storage subcircuit 21, a switch subcircuit 22 and a control subcircuit 23. The energy storage subcircuit 21 is coupled to the switch subcircuit 22 and is used to couple with the power supply circuit 101; wherein the control subcircuit 23 is coupled to the energy storage subcircuit 21 and the switch subcircuit 22 so as to control the switch subcircuit 22 using any of the control methods of the totem pole circuit described in this document.

[0032] For easier understanding, please continue to refer to Figure 3 , Figure 3 It is a structural diagram of a specific embodiment of the totem pole circuit of the present application.

[0033] In which, taking the totem pole circuit 30 as a totem pole PFC (Power Factor Correction) circuit as an example, the energy storage subcircuit 31 in the totem pole circuit 30 may specifically include an energy storage inductor Ln, the switch subcircuit 32 may specifically include a first switch tube S1, a second switch tube S2, a third switch tube S3 and a fourth switch tube S4, and the totem pole circuit 30 may specifically further include an energy storage capacitor Cn; the first end of the energy storage inductor Ln is used to couple with the first end of the power supply circuit 101, the second end of the energy storage inductor Ln is coupled to the first end of the first switch tube S1 and the second end of the second switch tube S2, and the second end of the first switch tube S1 is coupled to the third switch tube S4. The second end of S3 and the first end of the energy storage capacitor Cn are used to couple with the first end Vbus+ of the signal function circuit (not shown in the figure), the first end of the third switch tube S3 is coupled with the second end of the fourth switch tube S4, and is used to couple with the second end of the power supply circuit 101, the first end of the second switch tube S2 is coupled with the first end of the fourth switch tube S4 and the second end of the energy storage capacitor Cn, and is used to couple with the second end Vbus- of the signal function circuit, and the third end of each switch tube in the first switch tube S1, the second switch tube S2, the third switch tube S3 and the fourth switch tube S4 are coupled to the control subcircuit (not shown in the figure).

[0034] It is worth noting that the first switch tube S1 and the second switch tube S2 are high-frequency tubes, the third switch tube S3 and the fourth switch tube S4 are industrial frequency tubes, and when the input voltage Uin provided by the power supply circuit 101 is in the positive half cycle, that is, the input voltage Uin is greater than 0, the second switch tube S2 is an energy storage tube, and the first switch tube S1 is a freewheeling tube; when the input voltage Uin is in the negative half cycle, that is, the input voltage Uin is less than 0, the first switch tube S1 is an energy storage tube, and the second switch tube S2 is a freewheeling tube.

[0035] The signal function circuit can be understood as a load circuit that uses the totem pole circuit 30 to realize power supply, and can also be understood as a back-end function circuit of the totem pole circuit 30, so as to realize any reasonable signal function.

[0036] In addition, the term "coupled" herein refers to any direct and indirect connection means. Therefore, if the first circuit is described as being coupled to the second circuit, it means that the first circuit can be directly connected to the second circuit through electrical connection or signal connection methods such as wireless transmission, optical transmission, etc., or can be indirectly connected to the second circuit through other circuits or connection means.

[0037] In other embodiments, the energy storage subcircuit 31 may specifically include a larger number of inductors, and / or resistors, and / or capacitors to form an overall inductive energy storage unit; the switch subcircuit 32 may specifically include only a first switch tube S1 and a second switch tube S2; the energy storage capacitor Cn may also be removed, that is, the totem pole circuit 30 may specifically be any other reasonable totem pole PFC circuit topology, which is determined by the actual application scenario and is not limited in this application.

[0038] Specifically, the control subcircuit is used to sample the switch subcircuit 32 to obtain the output voltage VbusReal output to the back-end signal function circuit.

[0039] S12: Obtain the cycle on time using the output voltage.

[0040] Please continue reading Figure 4 , Figure 4 is a control block diagram of the totem pole circuit 30 in the triangle current mode.

[0041] Specifically, the control subcircuit sets the voltage setpoint output by the switch subcircuit 32 to the signal function circuit, that is, the target output voltage VbusRef*, according to the current power supply demand of the signal function circuit, and then subtracts the output voltage VbusReal from the target output voltage VbusRef* to obtain the error value ERROR, so as to use a PI controller (proportional integral controller) to implement feedback regulation control on the error value ERROR to obtain the input power dimension P.

[0042] Among them, the input power dimension P is calculated by the formula L / U 2 rms (L is the equivalent inductance value L of the energy storage subcircuit 31, U rms is the average value of the output voltage VbusReal) to obtain the cycle on time Ton, and the cycle on time Ton is the real time value.

[0043] It is worth mentioning that PWM is a technology that controls electrical signals by adjusting the pulse width. The PWM count value PRD refers to the count value used by the timer when generating a PWM signal, which determines the period and duty cycle of the PWM signal.

[0044] Specific setting method of PWM count value PRD:

[0045] ‌Time base module TB settings‌:

[0046] TBPRD: Set the PWM count period register to determine the period of the PWM signal.

[0047] TBPHS: Phase control register, used to control the phase of each output when multiple PWMs are synchronized.

[0048] TBCTL: Control register of TB, used to set synchronization logic, counting mode, etc.

[0049] TBCTR: Current count value register, reflects the current value of the counter in real time.

[0050] TBSTS: Status register, reflecting the status of the TB module.

[0051] ‌Count Compare Module (CC) Settings‌:

[0052] CMPCTL: Count comparison control register, which determines whether to use the shadow register and the reloading method of the count value.

[0053] CMPA and CMPB: Count comparison value setting registers CMPA and CMPB set the duty cycle of the PWM signal.

[0054] Among them, the PWM count value PRD is usually provided by the count register of the timer (such as ‌TBCTR), and is compared with the value of the count register through the comparison register (such as ‌CMPA, ‌CMPB), thereby controlling the switching time of the output signal. The setting of the PWM count value PRD directly affects the frequency and duty cycle of the output signal, and thus affects the control effect of the device.

[0055] Please continue reading Figure 5 , Figure 5 It is a waveform timing diagram of each signal in the totem pole circuit under the triangle current mode.

[0056] Among them, since the control method corresponding to the positive and negative half cycles of the input voltage Uin is consistent, the difference is that the outputs of the energy storage tube and the freewheeling tube will be exchanged in different half cycles. When the PWM count value PRD is at the zero crossing point to COMPA, the freewheeling tube will remain turned on to form the required negative current.

[0057] When the PWM count value PRD is between the first count comparison value COMPA and the second count comparison value COMPB, the dead zone timing is first performed, during which the energy storage tube and the freewheeling tube are both off. After the dead zone timing is completed, the energy storage tube is turned on, and the freewheeling tube continues to remain off, at which time the energy storage current Iac increases.

[0058] When the PWM count value PRD is at the second count comparison value COMPB until a new carrier synchronization arrives, a dead zone timing is first performed, during which both the energy storage tube and the freewheeling tube are not turned on.

[0059] After the dead time is completed, the freewheeling tube is turned on and the energy storage tube remains closed. At this time, the energy storage current Iac begins to decrease. Note that in an ideal situation, when the freewheeling tube counts, the energy storage current Iac drops to 0, forming a new ZCD (Zero Crossing Detector) signal.

[0060] In the above topology, the freewheeling tube time is not controlled, and the freewheeling tube needs to be turned on continuously until a new ZCD signal is generated.

[0061] In this process, the first count comparison value COMPA and the dead zone determine the magnitude of the negative current, and the short dead zone maintenance time is mainly used to prevent direct conduction, so the first count comparison value COMPA determines the magnitude of the negative current.

[0062] At present, the relevant technology mostly adopts a multi-segment fitting method for selecting the first count comparison value COMPA, that is, selecting an approximate first count comparison value COMPA according to the actual working conditions (different load conditions). At this time, the required negative current cannot be accurately controlled, and the first count comparison value COMPA in this case is not only applicable to a single situation, but also has a longer plateau period.

[0063] S13: Obtaining the input voltage in the energy storage subcircuit, the minimum value of the preset negative current, and the count cycle setting value.

[0064] Specifically, the control subcircuit samples the input voltage Uin in the energy storage subcircuit 31, that is, the input voltage Uin provided by the power supply circuit 101 to the energy storage subcircuit 31, and sets the minimum value iValley of the preset negative current Iys according to the current load condition.

[0065] The control subcircuit is also used to obtain a count period setting value PRD counter by reading the PWM count value PRD of the count value register in real time.

[0066] S14: Determine whether the periodic activation time is greater than the preset activation time.

[0067] Please continue reading Figure 6 , Figure 6 2 is a schematic diagram of the structure of an embodiment of an adaptive negative current.

[0068] It is understandable that in order to accurately control the negative current for different power conditions, that is, different load conditions, it is necessary to propose an adaptive negative current size, that is, to preset the negative current Iys size according to different voltage conditions in the same cycle, and obtain the first counting comparison value COMPA through the preset negative current Iys size.

[0069] In the initial stage when the totem pole circuit 30 receives input from the power circuit 101, the switching frequency of the control subcircuit controlling the switch subcircuit 32 generally gradually transitions from a high frequency stage to a low frequency stage and stabilizes at the low frequency stage.

[0070] Specifically, in the first stage, that is, the high-frequency stage, since the PWM sets the blanking window to limit the maximum frequency Fmax, such as 500kHZ (kilohertz), 550kHZ or 600kHZ and other reasonable signal frequencies, the PI control loop of the control subcircuit will be out of control, that is, this stage is in a pseudo-open-loop state, and the positive and negative currents of the energy storage current Iac are equal in a single switching cycle, that is, the plateau period. At this time, there is a large margin for achieving soft switching, and the target negative current needs to be reduced to reduce the target loss of this stage.

[0071] In the second stage, when the switching frequency of the switching subcircuit 32 gradually decreases to a relatively steady state, such as 300kHZ (kilohertz), 250kHZ or 350kHZ or any reasonable signal frequency and below, the PI control loop will take over again. At this stage, as the input voltage Uin increases, the forward conduction begins to increase. In order to achieve soft switching, the required negative current also needs to be accompanied by the increase in forward conduction to achieve soft switching.

[0072] It can be seen from this that in order to effectively implement the soft switching control method of the totem pole PFC circuit based on TCM (Triangular Current Mode), it is necessary to set negative currents of different sizes corresponding to different stages, and then use two different schemes to calculate the negative current time according to the preset negative current Iys, that is, the duration of the energy storage current Iac maintained at the negative current. The negative current time is determined by the first count comparison value COMPA and the dead time; and the negative current time corresponds to a preset turn-on time Tonys and a preset switching frequency Fys.

[0073] Specifically, the control subcircuit may read the current cycle on time Ton to determine whether the cycle on time Ton is greater than the preset on time Tonys.

[0074] It is understandable that the preset on time Tonys corresponds to the preset switching frequency Fys, so as to divide the control of the switch sub-circuit 32 by the control sub-circuit into two stages, or in other words, into two control modes.

[0075] The preset switching frequency Fys can be calculated based on the highest switching frequency supported by the totem pole circuit 30 .

[0076] If the current cycle opening time Ton is greater than the preset opening time Tonys, S15 is executed; if the current cycle opening time Ton is not greater than the preset opening time Tonys, S110 is executed.

[0077] S15: Obtaining the maximum value of the energy storage current in the energy storage subcircuit and the operation count comparison value.

[0078] The control subcircuit can specifically sample the energy storage current Iac of the energy storage subcircuit 31 from the energy storage subcircuit 31, and determine the maximum value iPeak of the energy storage current Iac; or, the control subcircuit can specifically use the current input voltage Uin, the equivalent inductance value L of the energy storage subcircuit 31 and the cycle opening time Ton to calculate the maximum value iPeak of the energy storage current Iac, so as to reduce the demand for the current sampling accuracy of the control subcircuit, and avoid the inability to accurately sample the peak value of the energy storage current Iac, that is, the scenario of the maximum value iPeak of the energy storage current Iac, which restricts the effective implementation of this embodiment.

[0079] Furthermore, the control sub-circuit is also used to obtain the operation count comparison value COMPBy corresponding to the previous signal cycle of the drive control signal sent to the switch sub-circuit 22.

[0080] S16: Obtain a first count comparison value by using the count cycle setting value, the calculated count comparison value, the maximum value and the minimum value.

[0081] Please continue reading Figure 7 , Figure 7 yes Figure 1 Schematic diagram of the waveform timing of each signal in the control method of the totem pole circuit.

[0082] Specifically, after obtaining the count cycle setting value PRD counter, the operation count comparison value COMPBy, the maximum value iPeak of the energy storage current Iac and the minimum value iValley of the preset negative current Iys, the control subcircuit can use the preset function to calculate the first count comparison value COMPA.

[0083] Among them, the first counting comparison value COMPA is negatively correlated with the minimum value iValley of the preset negative current Iys, that is, the larger the minimum value iValley of the preset negative current Iys, the smaller the first counting comparison value COMPA, so that the first counting comparison value COMPA can be calculated according to the preset value of the adaptive negative current, and the negative current of the energy storage current Iac can be precisely controlled through the first counting comparison value COMPA.

[0084] S17: Obtain a second counting comparison value using the first counting comparison value and the cycle opening time.

[0085] The control subcircuit is further used to calculate a second count comparison value COMPA using the first count comparison value COMPA and the cycle on time Ton to obtain a second count comparison value COMPB, such as adding the first count comparison value COMPA to the cycle on time Ton to obtain the second count comparison value COMPB.

[0086] S18: Generate a first control signal using the count cycle setting value, the first count comparison value and the second count comparison value.

[0087] It can be understood that in PWM technology, the count period setting value PRD counter will set the period of the PWM signal, and the second count comparison value COMPB and the first count comparison value COMPA will set the duty cycle of the PWM signal, so that after obtaining the count period setting value PRD counter, the first count comparison value COMPA and the second count comparison value COMPB, the first control signal PWM1 can be generated accordingly.

[0088] The first control signal PWM1 is a PWM signal.

[0089] The operation count comparison value COMPBy is the second count comparison value COMPB of the previous signal cycle of the first control signal PWM1.

[0090] It is worth noting that the control subcircuit can specifically divide the control stage according to whether the cycle opening time Ton is greater than the preset opening time Tonys, and the cycle opening time Ton is not greater than the preset opening time Tonys is set as the first stage, that is, the high-frequency control stage, and the cycle opening time Ton is greater than the preset opening time Tonys is set as the second stage, that is, the low-frequency control stage.

[0091] When the control subcircuit initially enters the low-frequency control stage, the operation count comparison value COMPBy obtained is actually the fourth count comparison value COMPB1 obtained in the high-frequency control stage, and the first count comparison value COMPA is calculated in sequence through the operation count comparison value COMPBy with each signal cycle, and then the second count comparison value COMPB of the current signal cycle is calculated by the first count comparison value COMPA and the cycle on time Ton.

[0092] S19: Utilizing the first control signal to adjust the switch state of the switch sub-circuit to adjust the energy storage current and the output voltage.

[0093] Specifically, the control subcircuit is also used to send the currently generated first control signal PWM1 to the switch subcircuit 32, so that the switch subcircuit 32 is triggered to turn on or off under the action of the first control signal PWM1, so as to adjust the energy storage current Iac output by the energy storage subcircuit 31 to the switch subcircuit 32, and adjust the output voltage VbusReal output by the switch subcircuit 32 to the back-end signal function circuit.

[0094] S110: Obtain the per unit coefficient using the output voltage.

[0095] It is understandable that when the control subcircuit determines that the current cycle on-time Ton is not greater than the preset on-time Tonys, it adopts the high-frequency control mode, that is, the current actual corresponding open-loop control mode.

[0096] The per-unit coefficient Kt-C is obtained by a PI controller using an actual control loop of the output voltage VbusReal.

[0097] S111: Subtract the input voltage from the output voltage to obtain a voltage difference.

[0098] Specifically, the control subcircuit obtains the voltage difference △U by subtracting the input voltage Uin from the currently acquired output voltage VbusReal, which can also be understood as obtaining the voltage difference △U by subtracting the phase voltage and the bus voltage in the plateau period.

[0099] S112: Subtract the minimum value from the zero current to obtain the current difference.

[0100] The control subcircuit obtains the current difference Ier by subtracting the minimum value iValley of the preset negative current Iys from the zero current, that is, the current difference Ier is actually the absolute value of the minimum value iValley of the preset negative current Iys.

[0101] Among them, the minimum value iValley of the preset negative current Iys can be specifically set according to different load conditions, that is, different signal function circuits at the rear end of the switch sub-circuit 32 will correspond to different minimum values ​​iValley of the preset negative current Iys.

[0102] In some embodiments, when the energy storage current Iac is in a plateau period, the negative current minimum value iValley of the energy storage current Iac is approximately -1A (ampere).

[0103] S113: multiply the product of the equivalent inductance value of the energy storage sub-circuit by the current difference value by the voltage difference value, and multiply the product by the per-unit coefficient to obtain a third counting comparison value.

[0104] It is understandable that the control subcircuit can specifically calculate the third counting comparison value COMPA1=(L*di) / △U*Kt-C using the following formula;

[0105] Among them, △U is the difference between the output voltage VbusReal and the input voltage Uin; L is the equivalent inductance value; di is the difference between the zero current and the minimum value iValley; Kt-C is the per-unit coefficient.

[0106] S114: Obtain a fourth counting comparison value using the third counting comparison value and the cycle opening time.

[0107] The control sub-circuit adds the third count comparison value COMPA1 to the cycle on time Ton to obtain a fourth count comparison value COMPB1.

[0108] S115: Generate a second control signal using the count cycle setting value, the third count comparison value, and the fourth count comparison value.

[0109] Similarly, the count period setting value PRD counter will set the period of the PWM signal, and the third count comparison value COMPA1 and the fourth count comparison value COMPB1 will set the duty cycle of the PWM signal, so that after obtaining the count period setting value PRDcounter, the third count comparison value COMPA1 and the fourth count comparison value COMPB1, the second control signal PWM2 can be generated accordingly.

[0110] The second control signal PWM2 also corresponds to a PWM signal.

[0111] S116: Utilize the second control signal to adjust the switch state of the switch sub-circuit to adjust the energy storage current and the output voltage.

[0112] At this stage, the control subcircuit is also used to send the currently generated second control signal PWM2 to the switch subcircuit 32, so that the switch subcircuit 32 is triggered to turn on or off under the action of the second control signal PWM2, so as to adjust the energy storage current Iac output by the energy storage subcircuit 31 to the switch subcircuit 32, and adjust the output voltage VbusReal output by the switch subcircuit 32 to the back-end signal function circuit.

[0113] The above scheme obtains the first counting comparison value COMPA by utilizing the preset minimum value iValley of the negative current Iys and the maximum value iPeak of the energy storage current Iac to achieve corresponding control, thereby being able to adapt to the preset value of the negative current and the peak value change of the energy storage current Iac, effectively improving the conversion efficiency of the totem pole circuit 30 at different periods, and reducing the waveform distortion of the electrical signal to reduce the switching loss, and also being able to define the negative current according to actual conditions.

[0114] Furthermore, in some embodiments, in the above S13, it may specifically include: multiplying the input voltage Uin by a preset load factor KU-I to obtain a minimum value iValley.

[0115] It can be understood that the minimum value iValley of the preset negative current Iys can be specifically set according to different load conditions, and different load conditions correspond to different preset load coefficients KU-I, so that the minimum value iValley of the preset negative current Iys can be obtained by multiplying the input voltage Uin by the preset load coefficient KU-I, that is, the minimum value iValley of the preset negative current Iys is obtained by using the calculation formula iValley=Uin*KU-I.

[0116] In some embodiments, the preset load factor KU-I may specifically be 0.005-0.01, which is not limited in this application.

[0117] Furthermore, in some embodiments, in the above S13, it may specifically include: acquiring a counting period value PRD when the energy storage current Iac passes through zero to obtain a counting period setting value PRD counter.

[0118] Specifically, the counting cycle value PRD in the counting cycle register is read in real time to determine the counting cycle value PRD when the energy storage current Iac passes through zero as the counting cycle setting value PRD counter.

[0119] Furthermore, in some embodiments, in the above S15, it may specifically include: dividing the input voltage Uin by the equivalent inductance L of the energy storage subcircuit 31, and multiplying the result by the cycle on time Ton to obtain a maximum value iPeak.

[0120] Specifically, the control subcircuit can use the following formula to calculate the maximum value iPeak of the energy storage current Iac:

[0121] iPeak=(Uin / L)*Ton;

[0122] Where Uin is the input voltage; L is the equivalent inductance value; Ton is the on-time within a single switching cycle, or a known value calculated by the previous control loop.

[0123] Furthermore, in some embodiments, the above S16 may specifically include: multiplying the difference between the count period setting value PRDcounter and the operation count comparison value COMPBy by the maximum value iPeak, and dividing the difference by the minimum value iValley to obtain the first count comparison value COMPA.

[0124] Specifically, the control subcircuit may use the following formula to calculate the first count comparison value COMPA:

[0125] COMPA=(PRD counter-COMPBy)*iPeak / (iValley);

[0126] Among them, PRD counter is the carrier synchronization time value when the energy storage current Iac passes through zero in the previous signal cycle. The counting cycle setting value PRD counter can be read at the beginning of a new ZCD; COMPBy is the loading value of the previous signal cycle; iValley is the negative current valley value of the energy storage current Iac currently required.

[0127] Furthermore, in some embodiments, before the above S14, the following may be specifically included: using the blanking window to limit the maximum frequency Fmax to obtain the initial opening time Tonc; multiplying the initial opening time Tonc by the set proportional coefficient Kb to obtain the preset opening time Tonys.

[0128] It is understandable that in PWM technology, a blanking window is usually provided, which sets a maximum upper limit on the frequency of the corresponding PWM signal, that is, the frequency of the PWM signal generated thereby will never exceed the maximum frequency Fmax limited by the blanking window.

[0129] Among them, the blanking window limit maximum frequency Fmax in the actual PWM signal generation process will correspond to a specific opening time, that is, the initial opening time Tonc, so that the initial opening time Tonc can be multiplied by a set proportional coefficient Kb to obtain the preset opening time Tonys, that is, Tonys=Tonc*Kb.

[0130] The maximum frequency Fmax of the blanking window limit is specifically set according to the maximum switching frequency supported by different totem pole circuits 30 .

[0131] In some embodiments, the set proportional coefficient Kb can be any reasonable proportional coefficient such as 1 / 4, 1 / 3 or 1 / 5, and is preferably 1 / 4, which is not limited in the present application.

[0132] Furthermore, in some embodiments, before the above S14, the method may further include: obtaining a preset switching time Tonys by using the preset switching frequency Fys.

[0133] It is understandable that the preset opening time Tonys specifically corresponds to a preset switching frequency Fys and satisfies a specific functional relationship. The control subcircuit can also use the specific functional relationship to perform corresponding calculations on the preset switching frequency Fys to obtain the preset opening time Tonys.

[0134] Furthermore, in some embodiments, the above S14 is specifically replaced by including: detecting the signal frequency of the first control signal PWM1 or the second control signal PWM2 in the previous signal cycle to determine whether the signal frequency is greater than the preset switching frequency Fys.

[0135] If the signal frequency is not greater than the preset switching frequency Fys, then S15 is executed; if the signal frequency is greater than the preset switching frequency Fys, then S110 is executed.

[0136] This application also provides an electronic device, see Figure 8 , Figure 8 1 is a schematic diagram of the structure of an electronic device of the present application. In this embodiment, the electronic device 40 includes a housing 41 and a totem pole circuit 42 connected to the housing 41 .

[0137] It should be noted that the totem pole circuit 42 described in this embodiment is the totem pole circuit 20 or the totem pole circuit 30 described in any one of the above embodiments. Figure 1-Figure 7 And the related text content will not be repeated here.

[0138] The beneficial effect of the present application is as follows: Different from the prior art, the control method of the totem pole circuit provided by the present application obtains the output voltage in the switch subcircuit, obtains the cycle opening time and the second counting comparison value by using the output voltage, and obtains the input voltage, the counting cycle setting value and the preset value of the adaptive negative current, that is, the minimum value of the preset negative current, in the energy storage subcircuit, so as to obtain the current peak value of the energy storage current in the energy storage subcircuit when the cycle opening time is greater than the preset opening time, that is, the maximum value of the energy storage current, so as to obtain the first counting comparison value by using the counting cycle setting value, the second counting comparison value, the maximum value of the energy storage current and the minimum value of the preset negative current, and then generate the first control signal by using the counting cycle setting value, the second counting comparison value and the first counting comparison value, and adjust the switching state of the switch subcircuit by using the first control signal to adjust the energy storage current and the output voltage, so as to be able to adapt to the preset value of the negative current and the peak value change of the energy storage current, effectively improve the conversion efficiency of the totem pole circuit in different periods, reduce the waveform distortion of the electrical signal, so as to reduce the switching loss, and also define the negative current according to the actual situation.

[0139] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A control method for a totem pole circuit, wherein the totem pole circuit comprises an energy storage subcircuit and a switch subcircuit, wherein the energy storage subcircuit is coupled to the switch subcircuit and is used to couple to a power supply circuit, wherein: The control method of the totem pole circuit comprises: Obtaining an output voltage in the switch subcircuit; Obtaining a cycle on time using the output voltage; Obtaining an input voltage, a minimum value of a preset negative current, and a count cycle setting value in the energy storage subcircuit; In response to the cycle on time being greater than a preset on time, obtaining a maximum value of the energy storage current in the energy storage subcircuit and an operation count comparison value; The difference between the count cycle setting value and the operation count comparison value is multiplied by the maximum value and divided by the minimum value to obtain a first count comparison value; Adding the first count comparison value to the cycle opening time to obtain a second count comparison value; Generate a first control signal using the count cycle setting value, the first count comparison value and the second count comparison value; wherein the calculated count comparison value is the second count comparison value of the previous signal cycle of the first control signal; The first control signal is used to adjust the switch state of the switch subcircuit to adjust the energy storage current and the output voltage.

2. The control method of the totem pole circuit according to claim 1, characterized in that: In the step of obtaining the input voltage in the power supply circuit, the minimum value of the preset negative current and the count cycle setting value, it also includes: The input voltage is multiplied by a preset load factor to obtain the minimum value.

3. The control method of the totem pole circuit according to claim 1, characterized in that: In the step of obtaining the input voltage in the power supply circuit, the minimum value of the preset negative current and the count cycle setting value, it also includes: The counting cycle value when the energy storage current passes through zero is obtained to obtain the counting cycle setting value.

4. The control method of the totem pole circuit according to claim 1, characterized in that: The step of obtaining the maximum value of the energy storage current in the energy storage subcircuit comprises: The input voltage is divided by the equivalent inductance of the energy storage subcircuit and multiplied by the cycle on time to obtain the maximum value.

5. The control method of the totem pole circuit according to any one of claims 1 to 4, characterized in that: Before the step of obtaining the maximum value of the energy storage current in the energy storage subcircuit and the operation count comparison value in response to the cycle on time being greater than the preset on time, the method further includes: The initial opening time is obtained by limiting the maximum frequency using the blanking window; The initial opening time is multiplied by a set proportional coefficient to obtain the preset opening time.

6. The control method of the totem pole circuit according to any one of claims 1 to 4, characterized in that: Before the step of obtaining the maximum value of the energy storage current in the energy storage subcircuit in response to the cycle on time being greater than the preset on time, the method further includes: The preset switching time is obtained by using the preset switching frequency.

7. The control method of the totem pole circuit according to claim 1, characterized in that: The control method of the totem pole circuit further includes: In response to the cycle on time being not greater than the preset on time, obtaining a per-unit coefficient using the output voltage; Subtracting the input voltage from the output voltage to obtain a voltage difference; Subtract the minimum value from the zero current to obtain a current difference; The product of the equivalent inductance value of the energy storage subcircuit multiplied by the current difference value is divided by the voltage difference value, and the result is multiplied by the per-unit coefficient to obtain a third counting comparison value; Adding the third count comparison value to the cycle opening time to obtain a fourth count comparison value; Generate a second control signal using the count cycle setting value, the third count comparison value, and the fourth count comparison value; The second control signal is used to adjust the switch state of the switch subcircuit to adjust the energy storage current and the output voltage.

8. A totem pole circuit, characterized in that: The totem pole circuit includes an energy storage subcircuit, a switch subcircuit and a control subcircuit, wherein the energy storage subcircuit is coupled to the switch subcircuit and is used to couple with a power supply circuit, and the control subcircuit is coupled to the energy storage subcircuit and the switch subcircuit; The control subcircuit is used to control the switch subcircuit by adopting the control method of the totem pole circuit as described in any one of claims 1 to 7.

9. An electronic device, characterized in that: The electronic device comprises a housing and a totem pole circuit connected to the housing; Wherein, the totem pole circuit is the totem pole circuit as claimed in claim 8.

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