Power supply system and control method thereof, and electronic equipment

Abstract

The present application discloses a power supply system and a control method thereof, and an electronic device, wherein the power supply system includes: a voltage conversion circuit; a detection circuit for detecting the input voltage and / or output voltage of the voltage conversion circuit; and a control circuit connected to the detection circuit for controlling the dead time of the switch tube in the voltage conversion circuit according to the input voltage and / or the output voltage. Compared with the conventional solution in which the dead time of the switch tube is fixed, the present solution can adaptively adjust the dead time of some or all of the switch tubes in the voltage conversion circuit according to different input voltages and / or output voltages, thereby helping to improve the working efficiency of the power supply system.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of power supply control technology, and more specifically, to a power supply system and a control method thereof, and an electronic device. Background Art

[0002] At present, voltage conversion circuits (such as four-tube Buck-Boost circuits) are widely used in energy storage systems, photovoltaic optimizers and other fields. When traditional pulse width modulation is used, there will be large switching losses on the switch tubes of the voltage conversion circuit, and when the switching frequency is increased, it will seriously affect the power conversion efficiency of the voltage conversion circuit.

[0003] Soft switching technology is an effective way to reduce high switching losses at high frequencies. It can achieve zero voltage switching (ZVS) by utilizing the resonance between the power inductor and the parasitic capacitance of the switch tube during the dead time, thus significantly reducing switching losses.

[0004] For ease of control, the dead time and zero voltage switching current of the switch tube in the voltage conversion circuit are usually designed to be fixed values. However, the fixed dead time and zero voltage switching current may introduce additional body diode conduction losses or make it difficult to fully realize soft switching of the switch tube, resulting in lower operating efficiency of the power supply system. Summary of the invention

[0005] The embodiments of the present application provide a power supply system and a control method thereof, and an electronic device. The following introduces various aspects involved in the embodiments of the present application.

[0006] In a first aspect, a power supply system is provided, comprising: a voltage conversion circuit; a detection circuit for detecting an input voltage and / or an output voltage of the voltage conversion circuit; and a control circuit connected to the detection circuit, for controlling a dead time of a switch tube in the voltage conversion circuit according to the input voltage and / or the output voltage.

[0007] In a second aspect, a control method for a power supply system is provided, wherein the power supply system includes a voltage conversion circuit, and the method includes: detecting an input voltage and / or an output voltage of the voltage conversion circuit; and controlling a dead time of a switch tube in the voltage conversion circuit according to the input voltage and / or the output voltage.

[0008] According to a third aspect, an electronic device is provided, characterized in that it comprises a power supply system as described in the first aspect.

[0009] According to a fourth aspect, a computer-readable storage medium is provided, on which an executable code is stored. When the executable code is executed, the method described in the second aspect can be implemented.

[0010] According to a fifth aspect, a computer program product is provided, comprising an executable code, which, when executed, can implement the method described in the second aspect.

[0011] The embodiment of the present application provides a power supply system, including a voltage conversion circuit, a detection circuit and a control circuit. The detection circuit can first detect the input voltage and / or output voltage of the voltage conversion circuit, and then the control circuit can be used to control the dead time of the switch tube in the voltage conversion circuit according to the input voltage and / or output voltage. Compared with the traditional solution in which the dead time of all the switch tubes in the voltage conversion circuit is fixed, this solution can adaptively adjust the dead time of some or all of the switch tubes in the voltage conversion circuit according to different input voltages and / or output voltages, thereby helping to improve the working efficiency of the power supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 1 is a schematic diagram of the structure of a four-tube Buck-Boost circuit provided in an embodiment of the present application.

[0013] Figure 2 It is a structural diagram of a power supply system provided in one embodiment of the present application.

[0014] Figure 3 yes Figure 2 FIG. 1 is a schematic diagram of a waveform of a change in the inductor current of the first inductor under different working modes.

[0015] Figure 4 yes Figure 3 FIG. 4 is a schematic diagram of a waveform of the inductor current of the first inductor being reduced to a critical value.

[0016] Figure 5 It is a flowchart of a control method for a power supply system provided in an embodiment of the present application.

[0017] Figure 6 It is a structural schematic diagram of a control device of a power supply system provided in one embodiment of the present application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0019] It should be noted that, in the embodiments of the present application, descriptions of “first”, “second”, “third”, “fourth”, etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as “first”, “second”, “third”, “fourth” may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments may be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0020] With the continuous development of power electronics technology, voltage conversion circuits have been widely used in various occasions. For the intermediate bus converter in the distributed power system, the anode power supply in the power processing unit of the spacecraft electric propulsion system, and the two-stage active power factor corrector, where the input voltage variation range is wide and the output voltage is between the input voltage range, it is usually necessary to use a voltage conversion circuit with buck-boost characteristics. The voltage conversion circuit can include a four-tube Buck-Boost circuit, a Cuk circuit, a Zeta circuit, and a SEPIC circuit.

[0021] When conventional pulse width modulation is used, there will be large switching losses on the switch tube of the voltage conversion circuit. When the switching frequency is increased, the power conversion efficiency of the voltage conversion circuit will be seriously affected.

[0022] Soft switching technology is an effective way to reduce high switching losses at high frequencies. It can achieve zero voltage switching (ZVS) by utilizing the resonance between the power inductor and the parasitic capacitance of the switch tube during the dead time, thus significantly reducing switching losses. The following is an example of a four-tube Buck-Boost circuit.

[0023] Figure 1 A four-tube Buck-Boost circuit is provided in an embodiment of the present application, such as Figure 1 As shown, the four-tube Buck-Boost circuit 100 has a junction capacitance C 1 ~C 4 , switch tube Q 1 ~Q 4 Zero voltage shutdown can be achieved naturally. The main reason is: when the switch tube Q 1 ~Q 4 When turned off, the inductor current will give the corresponding junction capacitance C 1 ~C 4 Charging, thus limiting the switch tube Q 1 ~Q4 The voltage rise rate of Q 1 ~Q 4 Zero voltage shutdown.

[0024] It is understandable that if the switch tube Q is to be realized 1 ~Q 4 If the zero voltage is turned on, the junction capacitance can be discharged to zero through the inductor current, and the switch tube can achieve zero voltage turn-on. Figure 1 , it can be seen that Q 1 and Q 4 For the main control tube, if you intend to reduce the inductance L c The inductance value increases the current pulsation, then the inductance L c The inductor current i Lc will flow in the reverse direction through Q 2 or Q 3 Then, when Q 2 or Q 3 When off, i Lc Give Q 1 or Q 4 The junction capacitance discharges from B to A, and the switch tube Q 1 or Q 4 To achieve ZVS, create conditions. Similarly, for the switch tube Q 2 or Q 3 The inductor current i that achieves ZVS Lc , then the inductor current must flow from A to B.

[0025] For example, for the switch tube Q 1 and Q 2 In Q 1 Before turning off, the inductor current i Lc Need to be greater than zero (i.e., the inductor current i Lc From A to B). Thus, Q 1 When off, i Lc Junction capacitance C 1 Charge the junction capacitance C 2 Discharge. When the junction capacitance C 1 The voltage rises to V in , C 2 After the voltage drops to zero, Q 2 Zero voltage switching can be achieved.

[0026] In the shutdown Q 2 Before, the inductor current i Lc Need to be less than zero (i.e., the inductor current i Lc From B to A). Thus, Q 2 When off, i Lc Junction capacitance C2 Charge the junction capacitance C 1 Discharge. When the junction capacitance C 2 The voltage rises to V in , junction capacitance C 1 After the voltage drops to zero, Q 1 Zero voltage switching can be achieved.

[0027] According to the above analysis, it can be seen that in order to achieve the switch tube Q 1 and Q 2 To achieve ZVS, the following conditions must be met: 1) 1 Before turning off, the inductor current i Lc Must be greater than zero; 2) In Q 2 Before turning off, the inductor current i Lc Must be less than zero.

[0028] Similarly, for the switch tube Q 3 and Q 4 In order to achieve ZVS, the following conditions should be met: 1) 3 Before turning off, the inductor current i Lc Must be less than zero; 2) In Q 4 Before turning off, the inductor current i Lc Must be greater than zero.

[0029] For ease of control, the dead time and zero voltage switching current of the switch tube in the four-tube Buck-Boost circuit 100 are usually designed to be fixed values. However, the fixed dead time and zero voltage switching current may introduce additional parasitic diode (also called body diode) conduction loss or make it difficult to fully realize soft switching of the switch tube, resulting in low operating efficiency of the power supply system.

[0030] In order to solve the above problems, the embodiment of the present application provides a power supply system, including a voltage conversion circuit, a detection circuit and a control circuit. The detection circuit can first detect the input voltage and / or output voltage of the voltage conversion circuit, and then the control circuit can be used to control the dead time of the switch tube in the voltage conversion circuit according to the input voltage and / or output voltage. Compared with the traditional solution in which the dead time of all the switch tubes in the voltage conversion circuit is fixed, this solution can adaptively adjust the dead time of some or all of the switch tubes in the voltage conversion circuit according to different input voltages and / or output voltages, thereby helping to improve the working efficiency of the power supply system.

[0031] Figure 2 This is a schematic diagram of the structure of a power supply system provided in an embodiment of the present application. Figure 2 As shown, the power supply system 200 includes a voltage conversion circuit 210 , a detection circuit 220 and a control circuit 230 .

[0032] The voltage conversion circuit 210 may be a voltage conversion circuit with a buck-boost characteristic. The power input terminal of the voltage conversion circuit 210 may be used to receive an input voltage, and the voltage output terminal of the voltage conversion circuit 210 may be used to provide an output voltage for a load. The voltage conversion circuit 210 may be applied to fields such as energy storage systems and photovoltaic optimizers. The detection circuit 220 may be used to detect the input voltage and / or output voltage of the voltage conversion circuit 210; the control circuit may be used to control the dead time of some or all of the switch tubes in the voltage conversion circuit 210 according to the input voltage and / or output voltage of the voltage conversion circuit 210. Compared with the conventional solution in which the dead time of all the switch tubes in the voltage conversion circuit is fixed, this solution helps to improve the efficiency of the power supply system.

[0033] The voltage conversion circuit 210 may include multiple types of conversion circuits, such as a four-tube Buck-Boost circuit, a Cuk circuit, a Zeta circuit, and a SEPIC circuit. The solution in the embodiment of the present application can be applied to any type of voltage conversion circuit that requires adaptive adjustment of the dead time of the switch tube. Taking the voltage conversion circuit as a four-tube Buck-Boost circuit as an example, the solution for adaptive adjustment of the dead time of the switch tube in the voltage conversion circuit is described in detail.

[0034] In some embodiments, the voltage conversion circuit 210 may be a four-tube Buck-Boost circuit 210, which may include a power input terminal 211, a voltage output terminal 212, a first switch tube Q 1 , the second switch tube Q 2 , the third switch tube Q 3 , the fourth switch tube Q 4 and the first inductor L c The first switch tube Q 1 The input end of the second switch tube Q is connected to the positive electrode of the power input end 211. 2 The output end of the third switch tube Q is connected to the negative electrode of the power input terminal 211. 3 The input end of the fourth switch tube Q is connected to the positive electrode of the voltage output terminal 212. 4 The output end of the first inductor L is connected to the negative electrode of the voltage output end 212. c One end of the first inductor L is connected to the output end of the first switch tube 213. c The other end is connected to the fourth switch tube Q 4 It can be understood that the first switch tube Q 1 The output end of the second switch tube Q 2 The input end of the third switch tube Q 3 The output terminal of the fourth switch tube Q 4The power input terminal 211 can be used to receive an input voltage V in , the voltage output terminal 212 can be used to output the output voltage V out The four-tube Buck-Boost circuit 210 also includes an output capacitor C f , the four-tube Buck-Boost circuit 210 can be used to supply the load R Ld It should be understood that the four-tube Buck-Boost circuit 210 is the same circuit as the four-tube Buck-Boost circuit 100 mentioned above.

[0035] The detection circuit 220 is connected to the four-tube Buck-Boost circuit 210 and can be used to detect the input voltage V of the power input terminal 211 of the four-tube Buck-Boost circuit 210. in and / or the output voltage V of the voltage output terminal 212 out The detection circuit 220 may include an analog to digital converter (ADC), and the analog to digital converter ADC may be used to implement real-time digital monitoring of the voltage or current in the four-tube Buck-Boost circuit 210 .

[0036] The control circuit 230 is connected to the detection circuit 220 and can be used to detect the input voltage V in and / or the output voltage V of the voltage output terminal 212 out , to control the dead time of the switch tubes in the four-tube Buck-Boost circuit 210.

[0037] It should be noted that the control circuit 230 can control the input voltage V in and / or the output voltage V of the voltage output terminal 212 out , to control the dead time of some or all of the switches in the four-tube Buck-Boost circuit 210. As an example, the third switch Q can be fixed 3 And the fourth switch tube Q 4 The control circuit 230 can be used to control the input voltage V of the power input terminal 211 according to the dead time. in , controls the first switch tube Q 1 And the second switch tube Q 2 As another example, the first switch tube Q can be fixed 1 And the second switch tube Q 2 The control circuit 230 can be used to control the output voltage V of the voltage output terminal 212 according to the dead time. out , controls the third switch tube Q 3 And the fourth switch tube Q4 Of course, the control circuit 230 can also adjust the dead time of at least one switch tube according to the input voltage V in and output voltage V out , adaptively controlling the dead time of all switching tubes, thereby maximizing the efficiency of the power supply system.

[0038] Combine the following Figure 2 , an example is given to illustrate the control method of the dead time of each switching tube.

[0039] In some embodiments, the four switch tubes in the four-tube Buck-Boost circuit 210 generally use the same type of power devices. That is, the junction capacitance of the four switch tubes is also the same. Therefore, C 1 =C 2 =C 3 =C 4 =C oss If we define t dead Q is the switch tube 1 ~Q 4 The corresponding dead time. Definition I ZVS It is the minimum inductor current that can achieve ZVS when the switch is turned off.

[0040] For the first switch tube Q 1 And the second switch tube Q 2 For example, if we want to ensure that the first switch tube Q 1 Or the second switch tube Q 2 After shutdown, I ZVS The first switch tube Q 1 Or the second switch tube Q 2 The dead time t between the driving signals dead Internal junction capacitance C 1 or junction capacitance C 2 The voltage is charged to V in , while the junction capacitance C 2 or junction capacitance C 1 The voltage is released to zero. Then, t dead Need to meet:

[0041]

[0042] If I ZVS When set to a fixed value, it can be seen that the dead time t of the switch tube dead With input voltage V in is proportional to the input voltage V in To control the first switch tube Q 1 Dead time t dead1, thereby improving the working efficiency of the power supply system.

[0043] Similarly, for the third switch tube Q 3 And the fourth switch tube Q 4 For example, if we want to ensure that the third switch tube Q 3 Or the fourth switch tube Q 4 After shutdown, I ZVS The third switch tube Q 3 Or the fourth switch tube Q 4 The dead time t between the driving signals dead Internal junction capacitance C 3 or junction capacitance C 4 The voltage is charged to V out , while the junction capacitance C 3 or junction capacitance C 4 The voltage is released to zero. Then, t dead Need to meet:

[0044]

[0045] in I ZVS When the value is fixed, it can be seen that the dead time t of the switch tube dead With the output voltage V out is proportional to the output voltage V out To control the fourth switch tube Q 4 Dead time t dead4 , thereby improving the working efficiency of the power supply system.

[0046] After research, it is found that after the design of the four-tube Buck-Boost circuit 210 is completed, the device parameters in the four-tube Buck-Boost circuit 210 are basically fixed. However, when the power input terminal 211 receives different input voltages V in Or the voltage output terminal 212 outputs different output voltages V out The minimum inductor current I that can achieve ZVS is ZVS The value is changing. With input voltage V in Take V as an example. in When the input voltage is 100V, the minimum inductor current I that can achieve ZVS is ZVS It may be 2mA. in When the input voltage is 110V, the minimum inductor current I that can achieve ZVS is ZVS It may be 2.05mA. That is, for each different input voltage V in Or output voltage V out There will be different input voltages V in Or output voltage Vout Corresponding multiple optimal I ZVS Furthermore, there will be multiple corresponding optimal dead time t of the switch tube dead It should be noted that when the input voltage V in Or output voltage V out When the minimum inductor current I that can achieve ZVS is determined, ZVS It can be based on the electrical device parameters and input voltage V in Or output voltage V out Calculated.

[0047] Based on the above analysis, the embodiment of the present application has different input voltages V in Under this condition, multiple optimal dead time t corresponding to the switch tube can be dead Sampling is performed to obtain a first set of sampling data. Based on the first set of sampling data, the input voltage V in The dead time t of the switch tube dead , so that the control circuit 230 can quickly and accurately obtain different input voltages V in Under this condition, the optimal dead time t corresponding to the switch tube dead .

[0048] Similarly, the embodiment of the present application can also be used at different output voltages V out Under this condition, the optimal dead time t corresponding to the switch tube is dead Sampling is performed to obtain a second set of sampling data. Based on the second set of sampling data, the output voltage V out The dead time t of the switch tube dead , so that the control circuit 230 can quickly and accurately obtain different input voltages V in Under this condition, the optimal dead time t corresponding to the switch tube dead .

[0049] In some embodiments, the control circuit 230 can be used to control the input voltage V in , and the pre-established input voltage V in The dead time t of the switch tube dead The first mapping relationship between the first switch tube Q 1 Dead time t dead1 .

[0050] In some embodiments, the control circuit 230 can be used to control the output voltage V out , and the pre-established output voltage V out The dead time t of the switch tube dead The second mapping relationship between the fourth switch tube Q 4Dead time t dead4 .

[0051] It should be noted that, according to the different working modes of the four-tube Buck-Boost circuit, the first switch tube Q 1 And the fourth switch tube Q 4 When turned on, the first inductor L c The inductor current i Lc To achieve the optimal I ZVS That is to say, for the first switch tube Q 1 And the fourth switch tube Q 4 For example, the optimal I ZVS To achieve ZVS, further, the first switch tube Q 1 And the fourth switch tube Q 4 Existence and I ZVS The corresponding optimal dead time t dead .

[0052] In some embodiments, the input voltage V in The dead time t of the switch tube dead The mapping relationship between them is linearly fitted to obtain the input voltage V in The dead time t of the first switch dead1 The linear relationship between:

[0053] t dead1 =k 1 V in +m 1 (3)

[0054] Among them, k 1 and m 1 is the linear fitting coefficient.

[0055] Similarly, the output voltage V can also be calculated based on the second set of sampling data. out The dead time t of the switch tube dead The mapping relationship between them is linearly fitted to obtain the output voltage V out The dead time t of the fourth switch tube dead4 The linear relationship between:

[0056] t dead4 =k 2 V out +m 2 (4)

[0057] Among them, k 2 and m 2 is the linear fitting coefficient.

[0058] It should be noted that the first mapping relationship may be a linear mapping relationship, such as formula (3), and / or the second mapping relationship may be a linear mapping relationship, such as formula (4).

[0059] For the second switch tube Q 2 And the third switch tube Q 3 For example, when the second switch tube Q 2 Or the third switch tube Q 3 When turned on, the first inductor L c The inductor current i Lc Usually greater than the minimum inductor current I required to achieve ZVS ZVS , so the second switch tube Q 2 Or the third switch tube Q 3 The optimal dead time is determined in different ways. Figure 2 , to determine the second switch tube Q 2 Or the third switch tube Q 3 The dead time method is illustrated by an example.

[0060] In some embodiments, the detection circuit 220 can also be used to detect the second switch tube Q 2 When turned on, the first inductor L c The inductor current I L2 Next, the control circuit 230 can be used to control the input voltage V in And the second switch tube Q 2 When turned on, the first inductor L c The inductor current I L2 , to control the second switch tube Q 2 Dead time t dead2 From formula (1), we can derive the second switch tube Q 2 Dead time t dead2 Satisfies the following formula:

[0061]

[0062] It can be seen that when the detection circuit 220 detects the current inductor current I L2 and input voltage V in When , we can substitute into formula (5) to calculate the second switch tube Q 2 Dead time t dead2 , and then the control circuit 230 can be used to control the second switch tube Q 2 Dead time t dead2 .

[0063] In some embodiments, the detection circuit 220 can also be used to detect the third switch tube Q 3 When turned on, the first inductor L cThe inductor current I L3 Next, the control circuit 230 can be used to control the output voltage V out And the third switch tube Q 3 When turned on, the first inductor L c The inductor current I L3 , to control the third switch tube Q 3 Dead time t dead3 From formula (2), we can derive the third switch tube Q 3 Dead time t dead3 Satisfies the following formula:

[0064]

[0065] It can be seen that when the detection circuit 220 detects the current inductor current I L3 and input voltage V out When , we can substitute into formula (6) to calculate the third switch tube Q 3 Dead time t dead3 Then the control circuit 230 can be used to control the third switch tube Q 3 Dead time t dead3 .

[0066] In some embodiments, since the first switch tube Q 1 And the second switch tube Q 2 have the same model, and the first switch tube Q 1 And the second switch tube Q 2 have the same input voltage (i.e., the same input voltage V in ), according to formula (1) or formula (5), the second switch tube Q 2 Dead time t dead2 Satisfies the following formula:

[0067] t dead2 I L2 =t dead1 I ZVS1 (7)

[0068] Among them, t dead1 The first switch tube Q 1 Dead time, I ZVS1 The first switch tube Q 1 When turned on, the first inductor L c The inductor current (for example, the first switch tube Q 1 Minimum inductor current to achieve ZVS), I L2 The second switch tube Q 2 When turned on, the first inductor L c The inductor current.

[0069] That is, when the detection circuit 220 detects that the second switch tube Q 2 Inductor current I at turn-on L2 When I L2 ,t dead1 and I ZVS1 Substitute into formula (7) to calculate the second switch Q 2 Dead time t dead2 , and then the control circuit 230 can be used to control the second switch tube Q 2 Dead time t dead2 .

[0070] In some embodiments, due to the third switch tube Q 3 And the fourth switch tube Q 4 The third switch tube Q 3 And the fourth switch tube Q 4 have the same output voltage (i.e. the same output voltage V out ), according to formula (2) or formula (6), the dead time t of the third switch tube can be derived dead3 Satisfies the following formula:

[0071] t dead3 I L3 =t dead4 I ZVS4 (8)

[0072] Among them, t dead4 The fourth switch tube Q 4 Dead time, I ZVS4 The fourth switch tube Q 4 When turned on, the first inductor L c The inductor current (for example, the fourth switch tube Q 4 Minimum inductor current to achieve ZVS), I L3 The third switch tube Q 3 When turned on, the first inductor L c The inductor current.

[0073] That is, when the detection circuit 220 detects that the third switch tube Q 3 Inductor current I at turn-on L3 When I L3 ,t dead4 and I ZVS4 Substitute into formula (8) to calculate the third switch Q 3 Dead time t dead3 Then the control circuit 230 can be used to control the third switch tube Q 3 Dead time t dead3 .

[0074] In some embodiments, Figure 3 As shown, the first inductor L is given in different working modes of the four-tube Buck-Boost circuit 210. c The inductor current i Lc The corresponding change waveform. Among them, point O represents Q 2 The turn-off moment, point A represents Q 4 The turn-off moment, point B represents Q 1 The turn-off moment, point C represents Q 3 It can be seen that in a cycle T s The four-transistor Buck-Boost circuit 210 has four operating modes.

[0075] Working mode 1: Q 1 and Q 4 At the same time, the first inductor L c The voltage across the two ends is V in , inductor current i Lc Linear increase.

[0076] Working mode 2: Q 1 and Q 3 At the same time, the first inductor L c The voltage across the two ends is V in -V out If V in >V out When the inductor current i Lc Linear increase; if V in ≤V out When the inductor current i Lc Linear decrease.

[0077] Working mode 3: Q 2 and Q 3 At the same time, the first inductor L c The voltage across the two ends is -V out , inductor current i Lc Linear decrease.

[0078] Working mode 4: Q 2 and Q 4 At the same time, the first inductor L c The voltage across the two ends is 0, and the inductor current i Lc Remain unchanged.

[0079] To make the first inductor L c The inductor current i Lc The pulsation and effective value of the switch tube can be minimized. 2 and Q 3 At the same time, Q4 Before Q 1 At this time, the first inductor L c The inductor current i Lc The valley value will remain at a fixed non-zero negative value -I ZVS , which is similar to the critical conduction mode of the inductor current, so it can be called pseudo boundary conduction mode (PBCM).

[0080] Based on the above analysis, when the four-tube Buck-Boost circuit 210 works in PBCM and the load is reduced, in order to ensure i Lc The effective value of is the smallest, and the current in segment AB should move downward in parallel. At this time, point A moves to the left and point B moves to the right. Correspondingly, Q 4 The duty cycle decreases, Q 1 The duty cycle increases.

[0081] It should be noted that, continue to refer to Figure 3 , let the inductor currents at points A and B be i LcA and i LcB If the load is gradually reduced, then i LcA and i LcB If the load current is reduced to the critical current value, i LcA or LcB Reduce to I ZVS .like Figure 4 (a), if V in <V out When the second switch tube Q 2 ZVS can be achieved just right. Figure 4 As shown in (b), if V in >V out When the third switch tube Q 3 ZVS can be achieved just right. Furthermore, if the load continues to decrease, Q 3 or Q 2 ZVS cannot be achieved.

[0082] It can be seen from the above content that the solution in the embodiment of the present application can adaptively adjust the dead time of the switch tube, thereby improving the conversion efficiency of the power supply system.

[0083] The embodiment of the present application also provides an electronic device, including any one of the power supply systems mentioned above. The electronic device may be, for example, a mobile phone, a tablet computer, a PDA, a wearable device, etc., and the present application does not make any specific restrictions on this.

[0084] Combination of the above Figures 1 to 4The power supply system embodiment of the present application is described in detail. Figure 5 and Figure 6 The control method embodiment of the power supply system of the present application is described in detail. It should be understood that the description of the method embodiment corresponds to the description of the power supply system embodiment, so the parts not described in detail can refer to the previous method embodiment.

[0085] Figure 5 FIG. 5 is a flow chart of a control method for a power supply system provided by an embodiment of the present application. The power supply system includes a voltage conversion circuit, and the method 500 includes steps S520 to S540.

[0086] In step S520, the input voltage and / or output voltage of the voltage conversion circuit is detected.

[0087] In step S540: according to the input voltage and / or the output voltage, the dead time of the switch tube in the voltage conversion circuit is controlled.

[0088] Optionally, the voltage conversion circuit is a four-tube Buck-Boost circuit, which includes: a power input end for receiving the input voltage; a voltage output end for outputting the output voltage; a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and a first inductor, wherein the input end of the first switch tube is connected to the positive electrode of the power input end, the output end of the second switch tube is connected to the negative electrode of the power input end, the input end of the third switch tube is connected to the positive electrode of the voltage output end, the output end of the fourth switch tube is connected to the negative electrode of the voltage output end, one end of the first inductor is connected to the output end of the first switch tube, and the other end of the first inductor is connected to the input end of the fourth switch tube; controlling the dead time of the switch tubes in the four-tube Buck-Boost circuit according to the input voltage and / or the output voltage includes: controlling the dead time of at least one of the first switch tube and the second switch tube according to the input voltage; and / or controlling the dead time of at least one of the third switch tube and the fourth switch tube according to the output voltage.

[0089] Optionally, controlling the dead time of the switch tube in the four-tube Buck-Boost circuit according to the input voltage and / or the output voltage includes: controlling the dead time of the first switch tube according to the input voltage and a pre-established first mapping relationship between the input voltage and the dead time of the switch tube; and / or controlling the dead time of the fourth switch tube according to the output voltage and a pre-established second mapping relationship between the output voltage and the dead time of the switch tube.

[0090] Optionally, the first mapping relationship is: dead1 =k 1 V in +m 1 , where t dead1 is the dead time of the first switch tube, V in is the input voltage, k 1 and m 1 is a linear fitting coefficient; and / or the second mapping relationship is: t dead4 =k 2 V out +m 2 , where t dead4 is the dead time of the fourth switch tube, V out is the output voltage, k 2 and m 2 is the linear fitting coefficient.

[0091] Optionally, the method further includes: detecting the inductor current of the first inductor when the second switch tube is turned on; and controlling the dead time of the second switch tube according to the input voltage and the inductor current of the first inductor when the second switch tube is turned on.

[0092] Optionally, the dead time t of the second switch tube dead2 Satisfies the following formula: dead2 I L2 =t dead1 I ZVS1 , where t dead1 is the dead time of the first switch tube, I ZVS1 is the inductor current of the first inductor when the first switch tube is turned on, I L2 is the inductor current of the first inductor when the second switch tube is turned on.

[0093] Optionally, the method further includes: detecting the inductor current of the first inductor when the third switch tube is turned on; and controlling the dead time of the third switch tube according to the input voltage and the inductor current of the first inductor when the third switch tube is turned on.

[0094] Optionally, the dead time t of the third switch tube dead3 Satisfies the following formula: dead3 I L3 =t dead4 I ZVS4 , where t dead4 is the dead time of the fourth switch tube, I ZVS4 is the inductor current of the first inductor when the fourth switch tube is turned on, I L3 is the inductor current of the first inductor when the third switch tube is turned on.

[0095] Combine the following Figure 6 A control device 600 of a power supply system in an embodiment of the present application is introduced. Figure 6 The dotted line in the figure indicates that the unit or module is optional. The device 600 can be used to implement the method described in the above method embodiment. The device 600 can be a computer or any type of electronic device.

[0096] The apparatus 600 may include one or more processors 610. The processor 610 may support the apparatus 600 to implement the method described in the above method embodiment.

[0097] The apparatus 600 may further include one or more memories 620. The memory 620 stores a program, which can be executed by the processor 610, so that the processor 610 executes the method described in the above method embodiment. The memory 620 may be independent of the processor 610 or integrated in the processor 610.

[0098] The apparatus 600 may further include a transceiver 630. The processor 610 may communicate with other devices through the transceiver 630. For example, the processor 610 may transmit and receive data with other devices through the transceiver 630.

[0099] The embodiment of the present application also provides a machine-readable storage medium for storing a program, and the program enables a computer to execute the method in each embodiment of the present application.

[0100] The embodiment of the present application also provides a computer program product. The computer program product includes a program. The program enables a computer to execute the method in each embodiment of the present application.

[0101] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present disclosure is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a machine-readable storage medium, or transmitted from one machine-readable storage medium to another machine-readable storage medium. For example, the computer instructions can be transmitted from a website site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (Digital Subscriber Line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center. The machine-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital video disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0102] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments of the present disclosure can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present disclosure.

[0103] In the several embodiments provided in the present disclosure, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0104] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0105] In addition, each functional unit in each embodiment of the present disclosure may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0106] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A power supply system, characterized in that: include: Voltage conversion circuit; A detection circuit, used for detecting an input voltage and / or an output voltage of the voltage conversion circuit; A control circuit, connected to the detection circuit, for controlling the dead time of the switch tube in the voltage conversion circuit according to the input voltage and / or the output voltage; The voltage conversion circuit is a four-tube Buck-Boost circuit, and the four-tube Buck-Boost circuit includes: A power input terminal, used for receiving the input voltage; A voltage output terminal, used for outputting the output voltage; a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and a first inductor, wherein the input end of the first switch tube is connected to the positive electrode of the power input end, the output end of the second switch tube is connected to the negative electrode of the power input end, the input end of the third switch tube is connected to the positive electrode of the voltage output end, the output end of the fourth switch tube is connected to the negative electrode of the voltage output end, one end of the first inductor is connected to the output end of the first switch tube, and the other end of the first inductor is connected to the input end of the fourth switch tube; The control circuit is used to control the dead time of at least one of the first switch tube and the second switch tube according to the input voltage; and / or The control circuit is used to control the dead time of at least one of the third switch tube and the fourth switch tube according to the output voltage; The detection circuit is also used to detect the inductor current of the first inductor when the second switch tube is turned on; The control circuit is used to control the dead time of the second switch tube according to the input voltage and the inductor current of the first inductor when the second switch tube is turned on.

2. The power supply system according to claim 1, characterized in that: The control circuit is used to control the dead time of the first switch tube according to the input voltage and a pre-established first mapping relationship between the input voltage and the dead time of the switch tube; and / or The control circuit is used to control the dead time of the fourth switch tube according to the output voltage and a pre-established second mapping relationship between the output voltage and the dead time of the switch tube.

3. The power supply system according to claim 2, characterized in that: The first mapping relationship is: dead1 =k1V in +m1, where t dead1 is the dead time of the first switch tube, V in is the input voltage, k1 and m1 are linear fitting coefficients; and / or The second mapping relationship is: dead4 =k2V out +m2, where t dead4 is the dead time of the fourth switch tube, V out is the output voltage, k2 and m2 are linear fitting coefficients.

4. The power supply system according to claim 1, characterized in that: The dead time of the second switch tube is t dead2 Satisfies the following formula: dead2 I L2 =t dead1 I ZVS1 , where t dead1 is the dead time of the first switch tube, I ZVS1 is the inductor current of the first inductor when the first switch tube is turned on, I L2 is the inductor current of the first inductor when the second switch tube is turned on.

5. The power supply system according to claim 1, characterized in that: The detection circuit is also used to detect the inductor current of the first inductor when the third switch tube is turned on; The control circuit is used to control the dead time of the third switch tube according to the input voltage and the inductor current of the first inductor when the third switch tube is turned on.

6. The power supply system according to claim 5, characterized in that: The dead time of the third switch tube is t dead3 Satisfies the following formula: dead3 I L3 =t dead4 I ZVS4 , where t dead4 is the dead time of the fourth switch tube, I ZVS4 is the inductor current of the first inductor when the fourth switch tube is turned on, I L3 is the inductor current of the first inductor when the third switch tube is turned on.

7. A control method for a power supply system, characterized in that: The power supply system includes a voltage conversion circuit, and the method includes: Detecting an input voltage and / or an output voltage of the voltage conversion circuit; Controlling the dead time of the switch tube in the voltage conversion circuit according to the input voltage and / or the output voltage; The voltage conversion circuit is a four-tube Buck-Boost circuit, and the four-tube Buck-Boost circuit includes: A power input terminal, used for receiving the input voltage; A voltage output terminal, used for outputting the output voltage; a first switch tube, a second switch tube, a third switch tube, a fourth switch tube and a first inductor, wherein the input end of the first switch tube is connected to the positive electrode of the power input end, the output end of the second switch tube is connected to the negative electrode of the power input end, the input end of the third switch tube is connected to the positive electrode of the voltage output end, the output end of the fourth switch tube is connected to the negative electrode of the voltage output end, one end of the first inductor is connected to the output end of the first switch tube, and the other end of the first inductor is connected to the input end of the fourth switch tube; The step of controlling the dead time of the switch tubes in the four-tube Buck-Boost circuit according to the input voltage and / or the output voltage includes: Controlling the dead time of at least one of the first switch tube and the second switch tube according to the input voltage; and / or Controlling the dead time of at least one of the third switch tube and the fourth switch tube according to the output voltage; The method further comprises: detecting an inductor current of the first inductor when the second switch tube is turned on; The dead time of the second switch tube is controlled according to the input voltage and the inductor current of the first inductor when the second switch tube is turned on.

8. The control method according to claim 7, characterized in that: The step of controlling the dead time of the switch tubes in the four-tube Buck-Boost circuit according to the input voltage and / or the output voltage includes: Controlling the dead time of the first switch tube according to the input voltage and a pre-established first mapping relationship between the input voltage and the dead time of the switch tube; and / or The dead time of the fourth switch tube is controlled according to the output voltage and a pre-established second mapping relationship between the output voltage and the dead time of the switch tube.

9. The control method according to claim 8, characterized in that: The first mapping relationship is: dead1 =k1V in +m1, where t dead1 is the dead time of the first switch tube, V in is the input voltage, k1 and m1 are linear fitting coefficients; and / or The second mapping relationship is: dead4 =k2V out +m2, where t dead4 is the dead time of the fourth switch tube, V out is the output voltage, k2 and m2 are linear fitting coefficients.

10. The control method according to claim 7, characterized in that: The dead time of the second switch tube is t dead2 Satisfies the following formula: dead2 I L2 =t dead1 I ZVS1 , where t dead1 is the dead time of the first switch tube, I ZVS1 is the inductor current of the first inductor when the first switch tube is turned on, I L2 is the inductor current of the first inductor when the second switch tube is turned on.

11. The control method according to claim 7, characterized in that: The method further comprises: detecting the inductor current of the first inductor when the third switch tube is turned on; The dead time of the third switch tube is controlled according to the input voltage and the inductor current of the first inductor when the third switch tube is turned on.

12. The control method according to claim 11, characterized in that: The dead time of the third switch tube is t dead3 Satisfies the following formula: dead3 I L3 =t dead4 I ZVS4 , where t dead4 is the dead time of the fourth switch tube, I ZVS4 is the inductor current of the first inductor when the fourth switch tube is turned on, I L3 is the inductor current of the first inductor when the third switch tube is turned on.

13. An electronic device, characterized in that: The invention comprises a power supply system as claimed in any one of claims 1 to 6.

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