Power conversion circuit, charging device and system

Abstract

A power conversion circuit and a charging device can support multiple charging modes and improve the battery charging rate. The circuit includes: a first end of a first switch element is coupled to an input power source through a first external terminal of the power conversion circuit, a second end of the first switch element is respectively coupled to a first end of a first energy storage element and a first end of a second switch element, a second end of the first energy storage element is respectively coupled to a first end of a third switch element and a first end of a fourth switch element, a second end of the second switch element is coupled to a battery through a second external terminal of the power conversion circuit, a second end of the fourth switch element is coupled to a second external terminal, a second end of the third switch element is grounded, a first end of a fifth switch element is coupled to a first external terminal, a second end of the fifth switch element is respectively coupled to a first end of a second energy storage element and a first end of a sixth switch element, a second end of the second energy storage element is coupled to a second external terminal, and a second end of the sixth switch element is grounded.

Description

Technical Field

[0001] The present application relates to the field of circuits, and more specifically, to a power conversion circuit, a charging device and a system. Background Art

[0002] Batteries have long been used as a power source for mobile electronic devices. Batteries provide energy in the form of voltage and current that allow circuits to operate. However, the energy stored in a battery is limited, and the battery loses power when the electronic device is in use. When a battery's energy supply is depleted, the battery's voltage will begin to drop from its rated voltage, and the electronic device that relies on the battery for power will no longer be able to continue to operate properly. In order to recharge the battery, some form of battery charging system is required.

[0003] Usually the battery charging system includes a power adapter and a charging device, and the energy and information transfer between the two is generally achieved through a USB cable. The function of the power adapter is to transfer the energy of the public power supply to the charging device in a certain voltage. The function of the charging device is to convert the energy obtained by the power adapter into a voltage and then transfer it to the battery.

[0004] Currently available battery charging systems only support a certain voltage mode, but different batteries support different charging currents. Under limited charging conditions, if the current supplied to the battery is too large, the battery may be damaged or even explode, or if the current supplied to the battery is too small, the charging process may be inefficient or completely ineffective. Summary of the invention

[0005] The present application provides a power conversion circuit, a charging device and a system, which can support multiple charging modes and effectively improve the charging rate of the battery.

[0006] In a first aspect, a power conversion circuit is provided, the power conversion circuit comprising: a first switch element, a second switch element, a third switch element, a fourth switch element, a fifth switch element, a sixth switch element, a first energy storage element, and a second energy storage element. In the power conversion circuit, the first end of the first switch element is coupled to the input power supply through the first external terminal of the power conversion circuit, the second end of the first switch element is respectively coupled to the first end of the first energy storage element and the first end of the second switch element, the second end of the first energy storage element is respectively coupled to the first end of the third switch element and the first end of the fourth switch element, the second end of the second switch element is coupled to the battery through the second external terminal of the power conversion circuit, the second end of the fourth switch element is coupled to the second external terminal, the second end of the third switch element is grounded, the first end of the fifth switch element is coupled to the first external terminal, the second end of the fifth switch element is respectively coupled to the first end of the second energy storage element and the first end of the sixth switch element, the second end of the second energy storage element is coupled to the second external terminal, and the second end of the sixth switch element is grounded.

[0007] The power conversion circuit can support a variety of different charging modes, so that the battery can be charged more quickly, thereby effectively improving the charging efficiency.

[0008] In a second aspect, a charging device is provided, which includes the power conversion circuit in the aforementioned aspect, and an information acquisition and signal control circuit and an input / output port coupled to the power conversion circuit, wherein the information acquisition and signal control circuit is coupled to the input / output port.

[0009] In a possible implementation of the second aspect, the information acquisition and signal control circuit includes: a digital core processing element, a battery information detection element, an output drive element, an information input element, a first power conversion element, and a second power conversion element. In the information acquisition and signal control circuit, the information input element, the first power conversion element, and the second power conversion element are respectively coupled to the input power supply through the first external terminal of the information acquisition and signal control circuit, the information input element is connected to the digital core processing element, the first power conversion element is connected to the digital core processing element, the second power conversion element is connected to the output drive element, the digital core processing element is coupled to the data line of the power adapter through the second external terminal of the information acquisition and signal control circuit, the digital core processing element is connected to the battery information detection element, the battery information detection element is coupled to the battery through the third external terminal of the information acquisition and signal control circuit, the digital core processing element is connected to the output drive element, and the output drive element is respectively coupled to each switch element of the power conversion circuit through the fourth external terminal of the information acquisition and signal control circuit.

[0010] In another possible implementation of the second aspect, the first end of the input / output port is connected to the input power of the power adapter, the second end of the input / output port is respectively coupled to the first external terminal of the power conversion circuit and the first external terminal of the information acquisition and signal control circuit, the third end of the input / output port is connected to the data line of the power adapter, and the fourth end of the input / output port is coupled to the second external terminal of the information acquisition and signal control circuit. Optionally, the input / output port is a USB port.

[0011] In a third aspect, a charging system is provided, the charging system comprising the charging device in the above aspects and implementations, and a power adapter and a battery element coupled to the charging device. The charging device and the battery element may be arranged in a device, which may be a terminal, a base station or an electric vehicle.

[0012] In a fourth aspect, a method for charging a battery is provided, which is executed in the power conversion circuit in the aforementioned aspect. Based on the composition structure of the power conversion circuit, the power conversion circuit can charge the battery according to a first charging mode, and the method includes: keeping the fifth switch element and the sixth switch element disconnected, in a first time period, the first switch element and the fourth switch element are in a closed state, and the second switch element and the third switch element are in an open state, and the first energy storage element is charged, and in a second time period after the first time period, the first switch element and the fourth switch element are in an open state, and the second switch element and the third switch element are in a closed state, and the first energy storage element is discharged.

[0013] The power conversion circuit can also charge the battery according to a second charging mode, and the method includes: keeping the fourth switch element, the fifth switch element and the sixth switch element open, and keeping the first switch element and the third switch element closed, in a first time period, the second switch element is in a closed state, and the battery is directly charged, and in a second time period after the first time period, the second switch element is in an open state, and charging the battery is suspended.

[0014] The power conversion circuit can also charge the battery according to a third charging mode, and the method includes: keeping the first switch element, the second switch element, the third switch element and the fourth switch element disconnected, in a first time period, the fifth switch element is in a closed state, and the sixth switch element is in an open state, and the second energy storage element is charged; in a second time period after the first time period, the fifth switch element is in an open state, and the sixth switch element is in a closed state, and the first energy storage element is discharged.

[0015] In a fifth aspect, a method for charging a battery is also provided, and the method is executed in a charging device in the aforementioned aspects and implementations. The charging device obtains input power by connecting to a power adapter, and obtains a charging current value supported by the battery by connecting to a battery, and the charging current value is greater than or equal to a preset current threshold, for example, the current threshold is set to 2A, 2.5A or 3A. The charging device determines that the power adapter supports a first charging mode, and then based on the first charging mode, keeps the fifth switch element and the sixth switch element disconnected, closes the first switch element and the fourth switch element in a first time period, and disconnects the second switch element and the third switch element, and charges the first energy storage element through the input power supply, and disconnects the first switch element and the fourth switch element in a second time period after the first time period, and closes the second switch element and the third switch element, and charges the battery through the discharge of the first energy storage element. In this method, the input power supply voltage of the charging device is close to twice the battery voltage, the charging current is large, and the battery is easy to be fully charged quickly, thereby effectively improving the battery charging rate.

[0016] In a sixth aspect, a method for charging a battery is also provided, and the method is executed in a charging device in the aforementioned aspects and implementations. The charging device obtains input power by connecting to a power adapter, and obtains a charging current value supported by the battery by connecting to a battery, wherein the charging current value is not less than a preset first current threshold and not greater than a preset second current threshold, and the first current threshold is less than the second current threshold, for example, the first current threshold is set to 2A, 2.5A or 3A, and the second current threshold is set to 5A. The charging device determines that the power adapter supports a second charging mode, and then based on the second charging mode, keeps the fourth switch element, the fifth switch element and the sixth switch element disconnected, keeps the first switch element and the third switch element closed, closes the second switch element in a first time period, and directly charges the battery through the input power, and disconnects the second switch element in a second time period after the first time period, and suspends charging the battery. In this method, the charging device directly charges the power energy into the battery, the circuit impedance is small, the energy loss is low, and the charging current is large, so that the overall energy loss of the charging device when charging the battery is low, and the battery is easy to be fully charged quickly, thereby effectively improving the battery charging rate.

[0017] In the seventh aspect, a method for charging a battery is also provided, and the method is executed in the charging device in the aforementioned aspects and implementations. The charging device obtains input power by connecting to a power adapter, and obtains the charging current value supported by the battery by connecting to the battery, and the charging current value is less than a preset current threshold, for example, the current threshold is set to 2A, 2.5A or 3A. The charging device determines that the power adapter supports a third charging mode, and then based on the third charging mode, keeps the first switch element, the second switch element, the third switch element and the fourth switch element disconnected, closes the fifth switch element and disconnects the sixth switch element in a first time period, charges the second energy storage element through the input power, and disconnects the fifth switch element and closes the sixth switch element in a second time period after the first time period, and charges the battery through the discharge of the second energy storage element. This method is conducive to the charging device outputting a stable charging current to the battery.

[0018] The first energy storage element and the second energy storage element in the aforementioned aspects and implementations, for example, the first energy storage element is a capacitor, the second energy storage element is an inductor, or the first energy storage element is composed of at least two capacitors connected in parallel, and the second energy storage element is composed of at least two inductors connected in series. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a charging device provided in an embodiment of the present invention.

[0020] Figure 2 It is a structural schematic diagram of a power conversion circuit provided by an embodiment of the present invention.

[0021] Figure 3 It is a structural schematic diagram of the information collection and signal control circuit provided by an embodiment of the present invention.

[0022] Figure 4 It is a structural schematic diagram of an input / output port provided by an embodiment of the present invention.

[0023] Figure 5 Schematic diagram of a charging system provided by an embodiment of the present invention.

[0024] Figure 6 It is a schematic diagram of an effective working circuit structure of a power conversion circuit based on a first charging mode provided by an embodiment of the present invention.

[0025] Figure 7 It is a schematic diagram of the control signal timing of the power conversion circuit provided by the present embodiment.

[0026] Figure 8It is a schematic diagram of an effective working circuit structure of a power conversion circuit based on the third charging mode provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0028] Figure 1 The charging device 100 provided in an embodiment of the present invention is shown, and the device is used to convert the input power energy according to a preset mode and provide it to the battery according to the charging current supported by the battery. Figure 1 In the embodiment, the charging device 100 includes a power conversion circuit 101 , an information collection and signal control circuit 102 and an input / output port 103 .

[0029] Regarding the power conversion circuit 101 in the charging device 100, Figure 2 FIG. 1 shows a structure of a power conversion circuit provided by an embodiment of the present invention. Figure 2 In the embodiment, the power conversion circuit 101 is used to convert the power supply VBUS into the charging current required by the battery. The power conversion circuit 101 includes: a first switch element 201, a second switch element 202, a third switch element 203, a fourth switch element 204, a fifth switch element 205, a sixth switch element 206, a first energy storage element 207 and a second energy storage element 208.

[0030] exist Figure 2 In the embodiment, a first end of the first switch element 201 is coupled to the power source VBUS through a first external terminal 209 of the power conversion circuit 101, a second end of the first switch element 201 is respectively coupled to a first end of the first energy storage element 207 and a first end of the second switch element 202, a second end of the first energy storage element 207 is respectively coupled to a first end of the third switch element 203 and a first end of the fourth switch element 204, a second end of the second switch element 202 is coupled to the battery through a second external terminal 210 of the power conversion circuit 101, a second end of the fourth switch element is coupled to the second external terminal 210, a second end of the third switch element is grounded, a first end of the fifth switch element 205 is coupled to the first external terminal 209, a second end of the fifth switch element 205 is respectively coupled to a first end of the second energy storage element 208 and a first end of the sixth switch element 206, a second end of the second energy storage element 208 is coupled to the second external terminal 210, and a second end of the sixth switch element 206 is grounded.

[0031] according to Figure 2As shown, the first switch element 201, the second switch element 202, the third switch element 203, the fourth switch element 204 and the first energy storage element 207 constitute a first sub-circuit in the power conversion circuit 101, and the fifth switch element 205, the sixth switch element 206 and the second energy storage element 208 constitute a second sub-circuit in the power conversion circuit 101, and the first sub-circuit and the second sub-circuit are connected in parallel.

[0032] Optionally, the first energy storage element 207 and the second energy storage element 208 may be one or more devices that can store energy and release the stored energy, for example, the device is a capacitor or an inductor. Optionally, the first energy storage element 207 and the second energy storage element 208 may have different device types. For example, the first energy storage element 207 is a capacitor, and the second energy storage element 208 is an inductor. For another example, the first energy storage element 207 is composed of at least two capacitors in parallel, and the second energy storage element 208 is composed of at least two inductors in series. The embodiment of the present invention does not limit the device type, device number and device composition form contained in the energy storage element.

[0033] Optionally, at least one of the first switching element 201, the second switching element 202, the third switching element 203, the fourth switching element 204, the fifth switching element 205 and the sixth switching element 206 is a metal oxide semiconductor field effect transistor (MOS) or a bipolar junction transistor (BJT), which is not limited in the embodiment of the present invention.

[0034] Regarding the information collection and signal control circuit 102 in the charging device 100, Figure 3 FIG. 1 shows a structure of an information collection and signal control circuit provided by an embodiment of the present invention. Figure 3 In the figure, the information acquisition and signal control circuit 102 includes: a digital core processing element (also represented as digital core) 301, a battery information detection element (also represented as BATinfo DET) 302, an output driver element (also represented as output driver) 303, an information input element (also represented as INPT info) 304, a first power conversion element (also represented as LD) 305 and a second power conversion element (also represented as LD) 306.

[0035] exist Figure 3 In the example, the information input element 304, the first power conversion element 305 and the second power conversion element 306 are connected to the power source V via the first external terminal 307 of the information acquisition and signal control circuit 102. BUSThe information input element 304 is connected to the digital core processing element 301, and the information input element 304 is used to collect the power supply V BUS The electrical characteristics of the device, for example, the electrical characteristics may be voltage and / or current information, and then the information input component 304 transmits the collected electrical characteristics to the digital core processing component 301. The first power conversion component 305 is connected to the digital core processing component 301, and the first power conversion component 305 is used to convert the power supply V BUS The voltage of the digital core processing element 301 is converted into the voltage V1 required by the digital core processing element 301. The second power conversion element 306 is connected to the output driving element 303. The second power conversion element 306 is used to convert the power V BUS The voltage is converted into the voltage V2 required by the output driving element 303. The digital core processing element 301 is coupled to the data line of the power adapter through the second external terminal 308 of the information acquisition and signal control circuit 102, and realizes data communication by reading the high and low levels of D+ / D-. For example, the communication is a protocol handshake between the power adapter and the charging device. The digital core processing element obtains the power V supported by the power adapter through the communication. BUS voltage range, or notify the power adapter to adjust the power V output to the charging device BUS voltage, so that the charging device will adjust the power supply V BUS The voltage is converted into the charging current required by the battery. The digital core processing element 301 is also connected to the battery information detection element 302, and the battery information detection element 302 is coupled to the battery through the third external terminal 309 of the information acquisition and signal control circuit 102. The battery information detection element 302 is used to collect battery system information, for example, the voltage and current information that the battery can support, or the battery retention capacity, and then the battery information detection element 302 transmits the collected battery system information to the digital core processing element 301. The digital core processing element 301 is also connected to the output drive element 303, for example, by means of a gate control bus. The digital core processing unit 301 analyzes the collected information, which includes the power supply V BUSThe digital core processing unit 301 generates a timing signal according to business needs, and then transmits the timing signal to the output driving element 303. The business need is the charging mode set by the charging device. Specifically, the current threshold is set in the digital core processing unit 301 in advance. Taking the current 2A as an example, if the charging current supported by the battery is greater than or equal to 2A, the business need may be to use a high-voltage direct charging mode, or the business need may be to use a low-voltage direct charging mode. If the charging current supported by the battery is less than 2A, the business need may be to use a Buck circuit mode. The timing signal is used to control the closing or opening of each switching element in the power conversion circuit 101, so that the energy storage element can store and release energy according to different charging modes. The output driving element 303 is coupled to each switching element of the power conversion circuit 101 through the fourth external terminal 310 of the information acquisition and signal control circuit 102. The output driving element 303 is used to convert the digital signal transmitted by the digital core processing element 301 into an analog signal, and then drive each switching element of the power conversion circuit 101 to close or open according to the analog signal, so as to enable the charging device to charge the battery according to business needs.

[0036] Optionally, the battery information detection element 302 and the information input element 304 can collect information periodically or dynamically according to charging needs, which is not limited in the embodiment of the present invention. The selection of the current threshold is determined based on the knowledge of those skilled in the art, and usually a larger charging current value, such as 2A, 2.5A, is taken. The current threshold can be flexibly set in the digital core processing unit 301 according to the use of the battery.

[0037] Regarding the input / output port 103 in the charging device 100, Figure 4 FIG. 1 shows a structure of an input / output port provided by an embodiment of the present invention. Figure 4 In the embodiment, the input / output port 103 is a USB port (also referred to as a USB port), which belongs to serial communication. Specifically, the first end 401 of the USB port is connected to the power source V BUS The second end 402 of the USB port is respectively coupled to the first external terminal 209 of the power conversion circuit 101 and the first external terminal 307 of the information acquisition and signal control circuit 102, and the power V BUSThe energy is transferred to the power conversion circuit 101 and the information acquisition and signal control circuit 102. The third end 403 of the USB port is connected to the data line of the power adapter, and the fourth end 404 of the USB port is coupled to the second external terminal 308 of the information acquisition and signal control circuit 102, and the high and low levels are transmitted through the fourth end 404 to realize the data reading and writing of the information acquisition and signal control circuit 102.

[0038] Combination Figures 1 to 4 Description of the charging device: Figure 5 FIG. 5 shows a charging system 500 provided by an embodiment of the present invention. Figure 5 In the embodiment, the charging system 500 includes: a charging device 100, a power adapter 501 and a battery element 502. One end of the power adapter 501 is connected to an external power supply, and the other end is connected to an input / output port 103 of the charging device 100. The power adapter 501 is used to convert the external power supply into the power V required by the charging device 100. BUS , and then connect the power supply V BUS The energy is output to the charging device 100, and its output type can be divided into an AC output type and a DC output type, which is not limited in the embodiment of the present invention. The power adapter 501 is also used to realize data communication and exchange with the charging device 100 through a data line. The charging device 100 can be an independent device or set in a device, and the device can be a terminal, a base station, an electric vehicle and other devices. The terminal can be a mobile phone (also known as a smart phone), a tablet computer (Tablet Personal Computer), a personal digital assistant (PDA), an e-book reader or a wearable device, etc. The base station can include various forms of macro base stations, micro base stations (also known as small stations), relay stations, access points, etc. The charging device 100 is connected to a battery element 502, which is used to charge the battery with the obtained energy. Optionally, the device can also include a battery element 502, and the number of batteries in the battery element 502 can be one or more. If the battery element 502 includes multiple batteries, the multiple batteries can be connected in series or in parallel, which is not limited in the embodiment of the present invention.

[0039] It should be noted that some components included in the charging device and charging system of the present application are expressed as "xx component", which only presents the components from a functional perspective and does not limit the implementation form of the components. For example, the components can be implemented by physical devices, or chips, or circuits / integrated circuits, and the embodiments of the present invention do not limit this.

[0040] Figure 2The power conversion circuit in the embodiment includes at least six switch elements, and its composition structure enables the charging device to select a suitable charging mode to charge the battery according to the charging current supported by the battery. In combination with the above description of the charging device, the different charging modes supported by the power conversion circuit are explained.

[0041] First charging mode: The charging current supported by the battery is greater than or equal to a preset current threshold (e.g., 2A, 2.5A, 3A), and the power conversion circuit is used to directly charge the battery with a high voltage. Figure 2 , the fifth switch element and the sixth switch element in the power conversion circuit remain disconnected, which makes the second energy storage element always in a non-working state. The so-called "remaining disconnected" is similar to the disconnected switch element being disconnected from other elements from the practical effect, because the impedance of the disconnected switch element is very large. Then in this first charging mode, the power conversion circuit is actually composed of the first sub-circuit consisting of the first switch element, the second switch element, the third switch element, the fourth switch element and the first energy storage element as an effective working circuit structure. Specifically, Figure 6 The effective working circuit structure of a power conversion circuit based on the first charging mode provided by an embodiment of the present invention is shown. Figure 6 In the embodiment, the first switch element is represented by Q1, the second switch element is represented by Q2, the third switch element is represented by Q3, the fourth switch element is represented by Q4, and the first energy storage element is a capacitor C FLY In the power conversion circuit, the capacitor C FLY The first end is connected to the power supply V through the switch element Q1. BUS Connected, capacitor C FLY The first end of the battery element ( Figure 6 The positive terminal of the battery is connected to the capacitor C FLY The second end of the capacitor C is grounded through the switch element Q3. FLY The second end of is also coupled to the positive terminal of the battery element through the switch element Q4, and the negative terminal of the battery element is grounded.

[0042] Combination Figure 7 As shown, in the first time period t ON In the embodiment, the switch element Q1 and the switch element Q4 are in the closed state, the switch element Q2 and the switch element Q3 are in the open state, and the input power supply V BUS Connect capacitor C FLY , then connected to the battery V BAT , at this time capacitor C FLY In the charging and energy storage state. In the first time period t ON The second time period t OFFIn the embodiment, the switch element Q1 and the switch element Q4 are in the open state, the switch element Q2 and the switch element Q3 are in the closed state, and the capacitor C FLY The lower plate of capacitor C is grounded. FLY The upper plate is connected to the battery V BAT , at this time capacitor C FLY In the discharge state, charging the battery element.

[0043] The first charging mode is generally applicable to the case where the power adapter supports a higher power voltage (e.g., 9V, 12V, or 20V) and the battery supports a larger charging current (e.g., 2A, 2.5A, or 3A). The charging device charges the battery in the first charging mode through the power conversion circuit. In the first time period t ON In the capacitor C FLY The two ends of the BUS and battery V BAT , and in the second time period t OFF The battery charging voltage is the capacitor C FLY The voltage across the two ends. Due to the input power V BUS Directly to capacitor C FLY The charging efficiency of the capacitor is high, and the energy input to the battery comes directly from the energy charged by the capacitor, making the input power supply voltage close to twice the battery voltage. FLY The energy loss is low and the charging current is large, so the battery can be fully charged quickly, thereby effectively increasing the battery charging rate.

[0044] Second charging mode: The charging current supported by the battery is greater than or equal to the first current threshold (e.g., 2A, 2.5A, or 3A) and less than the second current threshold (e.g., 5A). The power conversion circuit is used to directly charge the battery at a low voltage. Figure 2 , the fourth switch element, the fifth switch element and the sixth switch element in the power conversion circuit remain disconnected, which makes the second energy storage element in a non-working state. The first switch element and the third switch element remain closed, which makes the first energy storage element in a non-working state. Then in the power conversion circuit, one end of the second switch element is coupled to the power supply V BUS The other end of the second switch element is coupled to the positive terminal of the battery, and the negative terminal of the battery element is grounded.

[0045] Combination Figure 7 As shown, in the first time period t ON In the case of a second switch element being in a closed state, the input power supply V BUS Connect to battery V BAT , at this time, the battery element is directly charged. In the second time period tOFF In the embodiment of the present invention, the second switch element is in the off state, and the charging of the battery element is suspended.

[0046] Compared with the first charging mode, the first difference between the second charging mode is the different requirements for the charging current supported by the battery. For the second charging mode, since it is a low-voltage direct charge, the current input to the charging device is close to the charging current output to the battery, but the cable connecting the power adapter and the charging device usually supports a maximum current of 5A. If the current flowing through the cable is greater than 5A, the cable will be damaged, or a more expensive cable will be required to transmit the current, so the battery charging current cannot be greater than 5A. For the first charging mode, since it is a high-voltage direct charge, the voltage input to the charging device is close to twice the battery voltage, but the battery charging current is close to twice the current of the input charging device. Combined with the aforementioned current thresholds, taking currents of 2A and 5A as an example, the second charging mode is adopted, and the battery charging current (measured in I BAT indicates) must be between 2A and 5A, that is, 2A≤I BAT ≤5A, but in the first charging mode, the battery charging current must be greater than or equal to 2A, that is, 2A≤I BAT .

[0047] The second charging mode is different from the first charging mode in that the power supply voltage supported by the power adapter is different. For the second charging mode, the power adapter needs to provide the charging device with lower voltage and higher current power. For the first charging mode, the power adapter needs to provide the charging device with higher voltage and higher current power.

[0048] Since in the second charging mode, the charging device directly charges the power energy into the battery by closing and opening the second switch element of the power conversion circuit, the circuit impedance is small and the energy loss is low. BUS The voltage is close to the battery V BAT It is obvious that the charging device is charging at a low voltage, and the charging current is large, which makes the overall energy loss of the charging device lower when charging the battery, and the battery is easy to be fully charged quickly, thereby effectively improving the battery charging rate.

[0049] The third charging mode: the charging current supported by the battery is greater than or equal to the current threshold (for example, 2A), and the power conversion circuit is used to charge the battery in the Buck circuit mode. Figure 2, the first switch element, the second switch element, the third switch element and the fourth switch element in the power conversion circuit are always kept disconnected, so that the first energy storage element is always in a non-working state. Then in the third charging mode, the power conversion circuit is actually composed of the second sub-circuit composed of the fifth switch element, the sixth switch element and the second energy storage element as an effective working circuit structure, and the circuit is similar to a typical Buck circuit. Specifically, Figure 8 The effective working circuit structure of a power conversion circuit based on the third charging mode provided by an embodiment of the present invention is shown. Figure 8 In the embodiment, the fifth switch element is represented by Q5, the sixth switch element is represented by Q6, and the second energy storage element is an inductor L. In the power conversion circuit, the first end of the inductor L is connected to the power source V through the switch element Q5. BUS The first end of the inductor L is also grounded through the switch element Q6, and the second end of the inductor L is connected to the battery element ( Figure 8 The positive terminal of the Battery shown is coupled and connected, and the negative terminal of the battery element is grounded.

[0050] Combination Figure 7 As shown, in the first time period t ON In the example, the switch element Q5 is in the closed state, the switch element Q6 is in the open state, and the input power supply V BUS Connect the inductor L and then connect it to the battery V BAT , at this time, the inductor L is in a charging and energy storage state. In the second time period t OFF In the embodiment, the switch element Q5 is in an open state, the switch element Q6 is in a closed state, and the inductor L is in a discharge state to charge the battery element.

[0051] The third charging mode is usually suitable for the case where the battery charging current is small, such as I BAT <2A, and this mode has lower requirements on the power adapter than the first two modes. Due to the low current charging, compared with the aforementioned charging modes, the third charging mode is more conducive to the charging device outputting a stable charging current to the battery. Optionally, the second end of the second energy storage element is connected to the first end of another energy storage element (such as a capacitor), and the second end of the other energy storage element is grounded, which makes the charging current output to the battery more stable.

[0052] Regarding the switch element in the power conversion circuit described in the above embodiment, optionally, the switch element is closed or opened by changing the gate voltage of the switch element. For example, the first terminal of the switch element Q1 is connected to the power source V BUSThe second end of the switch element Q1 is coupled to other elements. When the charging device determines that the switch element Q1 needs to be closed, the switch element Q1 increases the gate voltage and makes the gate voltage higher than the voltage at the second end of the switch element Q1. At this time, the switch element Q1 is in a low-resistance on state. When the charging device determines that the switch element Q1 needs to be disconnected, the switch element Q1 reduces the gate voltage and makes the gate voltage lower than the voltage at the second end of the switch element Q1. At this time, the switch element Q1 is in a high-resistance off state. Due to the different types of switch elements, the corresponding implementation methods of closing or disconnecting the switch element will be different, and the embodiments of the present invention do not limit this.

[0053] In combination with the above description, the specific process of how the charging system charges the battery is described below.

[0054] The input / output port 103 of the charging device 100 obtains the input power V by connecting to the power adapter 501. BUS , and then respectively provide the power supply energy to the power conversion circuit 101 and the information collection and signal control circuit 102. The digital core processing element 301 in the charging device 100 communicates with the power adapter 501 through the input / output port 103, and then determines the charging mode adopted by the power conversion circuit 101 according to the charging mode supported by the power adapter 501, the charging current required by the battery element 502 and the preset current threshold. A current threshold can be preset in the digital core processing element, or two current thresholds (current lower limit and current upper limit) can be preset. The priority order of different charging modes can also be preset and flexibly adjusted according to the use of the battery. The following is explained through several examples, and the embodiments of the present invention are not limited to this.

[0055] For example, in the charging device 100, the digital core processing component 301 determines that the charging current required by the battery is 6A based on the battery system information collected by the battery information detection component 302. If a current threshold of 2A is preset, the digital core processing component 301 determines that 6A is greater than 2A, and based on the protocol communication with the power adapter 501, determines that the power adapter 501 supports the first charging mode, and then sets the state of the charging device to the first charging mode.

[0056] For another example, in the charging device 100, the digital core processing component 301 determines that the charging current required by the battery is 3A based on the battery system information collected by the battery information detection component 302. If the preset first current threshold (also called the lower current limit) is 2A, and the preset second current threshold (also called the upper current limit) is 5A, the digital core processing component 301 determines that 3A is between 2A and 5A, and based on the protocol communication with the power adapter 501, determines that the power adapter 501 supports the second charging mode, and then sets the state of the charging device to the second charging mode.

[0057] For another example, in the charging device 100, the digital core processing component 301 determines that the charging current required by the battery is 4A based on the battery system information collected by the battery information detection component 302. If a current threshold of 2A is preset, the digital core processing component 301 determines that 4A is greater than 2A. The digital core processing component 301 first determines whether the power adapter 501 supports the first charging mode based on the protocol communication with the power adapter 501. The result of the determination is that the power adapter 501 does not support the first charging mode. Then, the digital core processing component 301 determines whether the power adapter 501 supports the second charging mode, determines that the power adapter 501 supports the second charging mode, and then sets the state of the charging device to the second charging mode.

[0058] For another example, in the charging device 100, the digital core processing component 301 determines that the charging current required by the battery is 4A based on the battery system information collected by the battery information detection component 302. If the preset first current threshold (also called the lower current limit) is 2A, and the preset second current threshold (also called the upper current limit) is 5A, the digital core processing component 301 determines that 4A is between 2A and 5A, and based on the protocol communication with the power adapter 501, first determines whether the power adapter 501 supports the second charging mode. The judgment result is that the power adapter 501 does not support the second charging mode. Then, it is determined whether the power adapter 501 supports the first charging mode, and it is determined that the power adapter 501 supports the first charging mode, and then the state of the charging device is set to the first charging mode.

[0059] For another example, in the charging device 100, the digital core processing component 301 determines that the charging current required by the battery is 1A based on the battery system information collected by the battery information detection component 302. If a current threshold of 2A is preset, the digital core processing component 301 determines that 1A is less than 2A, and based on the protocol communication with the power adapter 501, determines that the power adapter 501 supports the third charging mode, and then sets the state of the charging device to the third charging mode.

[0060] In the charging device 100, the digital core processing element 301 performs protocol communication with the power adapter 501 through the input / output port 103, and prompts the power adapter 501 to adjust the power voltage and current input to the charging device 100 according to the determined charging mode. Based on the determined charging mode, the digital core processing element 301 drives each switch element of the power conversion circuit 101 to close or open through the output driving element 303, so as to realize the charging of the battery element 502 by the charging device 100. Optionally, the battery information detection element 302 detects that the battery element 502 is full, and then notifies the digital core processing element 301. The digital core processing element 301 performs protocol communication with the power adapter 501 through the input / output port 103, prompting the power adapter 501 to adjust the voltage input to the charging device 100 to 5V, and then drives the power conversion circuit 101 to exit the adopted charging mode through the output driving element 303. Since the input / output port 103 is usually a USB port, its standard voltage defaults to 5V.

[0061] Based on the description in the foregoing embodiments, the circuit structure of the charging device can support a variety of different charging modes, so that the battery can be charged more quickly, thereby effectively improving the charging efficiency.

[0062] The terms "first", "second", "third" and "fourth" etc. in the specification, claims and description of this application are used to distinguish different objects rather than to describe a specific order.

[0063] It should be understood that in the embodiments of the present invention, the same elements correspond to similar reference numerals. In addition, the above description of the embodiments of the present invention focuses on emphasizing the differences between the various embodiments, and the same or similar points not mentioned can be referenced to each other, and for the sake of brevity, they will not be repeated here.

[0064] It should also be understood that, in this article, the connection between A and B may mean that A and B are directly connected, or A and B are indirectly connected, for example, A is connected to B through one or more elements, and the embodiments of the present invention are not limited to this.

[0065] In addition, the term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0066] Those skilled in the art will appreciate that the digital core processing elements and method steps described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are 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 invention.

[0067] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the division of the components is only a logical function division, and there may be other division methods in actual implementation, such as multiple 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 communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0068] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power conversion circuit, characterized in that: include: a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a first energy storage element, and a second energy storage element; wherein, The first end of the first switch is coupled to the input power supply through the first external terminal of the power conversion circuit, the second end of the first switch is respectively coupled to the first end of the first energy storage element and the first end of the second switch, the second end of the first energy storage element is respectively coupled to the first end of the third switch and the first end of the fourth switch, the second end of the second switch is coupled to the battery through the second external terminal of the power conversion circuit, the second end of the fourth switch is coupled to the second external terminal, the second end of the third switch is grounded, the first end of the fifth switch is coupled to the first external terminal, the second end of the fifth switch is respectively coupled to the first end of the second energy storage element and the first end of the sixth switch, the second end of the second energy storage element is coupled to the second external terminal, and the second end of the sixth switch is grounded; When the charging current supported by the battery is greater than or equal to a preset first current threshold, and the voltage provided by the power source is greater than a first voltage threshold, the power conversion circuit is in a first charging mode and is used to directly charge the battery with a first charging voltage; When the charging current supported by the battery is greater than or equal to the first current threshold and less than a second current threshold, and the voltage provided by the power supply is less than the first voltage threshold, the power conversion circuit is in a second charging mode, and the power conversion circuit is used to directly charge the battery with a second charging voltage, and the second charging voltage is lower than the first charging voltage; When the charging current supported by the battery is less than the first current threshold, the power conversion circuit is in a third charging mode, and the power conversion circuit is used to directly charge the battery in a BUCK circuit mode.

2. The power conversion circuit according to claim 1, characterized in that: The power conversion circuit is used to charge the battery according to one of the following modes: Based on the first charging mode, the power conversion circuit is used to keep the fifth switch and the sixth switch open, in a first time period, the power conversion circuit is used to close the first switch and the fourth switch, and open the second switch and the third switch, and in a second time period after the first time period, the power conversion circuit is used to open the first switch and the fourth switch, and close the second switch and the third switch; Based on the second charging mode, the power conversion circuit is used to keep the fourth switch, the fifth switch and the sixth switch open, and keep the first switch and the third switch closed, in a first time period, the power conversion circuit is used to close the second switch, and in a second time period after the first time period, the power conversion circuit is used to open the second switch; Based on the third charging mode, the power conversion circuit is used to keep the first switch, the second switch, the third switch and the fourth switch open, in a first time period, the power conversion circuit is used to close the fifth switch and open the sixth switch, and in a second time period after the first time period, the power conversion circuit is used to open the fifth switch and close the sixth switch.

3. The power conversion circuit according to claim 1 or 2, characterized in that: The first energy storage element is a capacitor, and the second energy storage element is an inductor.

4. A charging device, characterized in that: It comprises a power conversion circuit as described in any one of claims 1 to 3, and an information acquisition and signal control circuit and an input / output port coupled to the power conversion circuit, wherein the information acquisition and signal control circuit is coupled to the input / output port.

5. The charging device according to claim 4, characterized in that: The information acquisition and signal control circuit includes: a digital core processing element, a battery information detection element, an output drive element, an information input element, a first power conversion element and a second power conversion element; wherein, The information input element, the first power conversion element and the second power conversion element are respectively coupled to the input power supply through the first external terminal of the information acquisition and signal control circuit, the information input element is connected to the digital core processing element, the first power conversion element is connected to the digital core processing element, the second power conversion element is connected to the output drive element, the digital core processing element is coupled to the data line of the power adapter through the second external terminal of the information acquisition and signal control circuit, the digital core processing element is connected to the battery information detection element, the battery information detection element is coupled to the battery through the third external terminal of the information acquisition and signal control circuit, the digital core processing element is connected to the output drive element, and the output drive element is respectively coupled to each switch of the power conversion circuit through the fourth external terminal of the information acquisition and signal control circuit.

6. The charging device according to claim 5, characterized in that: The first end of the input / output port is connected to the input power of the power adapter, the second end of the input / output port is respectively coupled to the first external end of the power conversion circuit and the first external end of the information acquisition and signal control circuit, the third end of the input / output port is connected to the data line of the power adapter, and the fourth end of the input / output port is coupled to the second external end of the information acquisition and signal control circuit.

7. The charging device according to any one of claims 4 to 6, characterized in that: The input / output port is a USB port.

8. A charging system, characterized in that: The invention comprises a charging device as claimed in any one of claims 4 to 7, and a power adapter and a battery element coupled to the charging device.

9. The charging system as claimed in claim 8, characterized in that The charging device and the battery element are arranged in a device, and the device is a terminal, a base station or an electric vehicle.

10. A method for charging a battery, characterized in that: The method is performed in the power conversion circuit as claimed in claim 1, The power conversion circuit charges the battery according to one of the following modes, and the method includes: Based on the first charging mode, the fifth switch and the sixth switch are kept disconnected, in a first time period, the first switch and the fourth switch are in a closed state, and the second switch and the third switch are in a disconnected state, and the first energy storage element is charged, and in a second time period after the first time period, the first switch and the fourth switch are in a disconnected state, and the second switch and the third switch are in a closed state, and the first energy storage element is discharged; Based on the second charging mode, the fourth switch, the fifth switch and the sixth switch are kept disconnected, and the first switch and the third switch are kept closed; in a first time period, the second switch is in a closed state, and the battery is directly charged; in a second time period after the first time period, the second switch is in an open state, and charging of the battery is suspended; Based on the third charging mode, the first switch, the second switch, the third switch and the fourth switch are kept disconnected, in a first time period, the fifth switch is in a closed state, and the sixth switch is in an open state, and the second energy storage element is charged, and in a second time period after the first time period, the fifth switch is in an open state, and the sixth switch is in a closed state, and the first energy storage element is discharged.

11. A method for charging a battery, characterized in that: The method is performed in the charging device according to any one of claims 4 to 7, and the method comprises: The charging device obtains input power by connecting to a power adapter; The charging device acquires a charging current value supported by the battery by connecting to the battery, and the charging current value is greater than or equal to a preset current threshold; The charging device determines that the power adapter supports a first charging mode; Based on the first charging mode, the charging device keeps the fifth switch and the sixth switch disconnected, closes the first switch and the fourth switch and disconnects the second switch and the third switch in a first time period, and charges the first energy storage element through the input power supply, and disconnects the first switch and the fourth switch and closes the second switch and the third switch in a second time period after the first time period, and charges the battery through the discharge of the first energy storage element.

12. A method for charging a battery, characterized in that: The method is performed in the charging device according to any one of claims 4 to 7, and the method comprises: The charging device obtains input power by connecting to a power adapter; The charging device acquires a charging current value supported by the battery by connecting to the battery, the charging current value is not less than a preset first current threshold and not greater than a preset second current threshold, and the first current threshold is less than the second current threshold; The charging device determines that the power adapter supports a second charging mode; Based on the second charging mode, the charging device keeps the fourth switch, the fifth switch and the sixth switch open, and keeps the first switch and the third switch closed; in a first time period, the second switch is closed to directly charge the battery through the input power supply; in a second time period after the first time period, the second switch is opened to suspend charging the battery.

13. A method for charging a battery, characterized in that: The method is performed in the charging device according to any one of claims 4 to 7, and the method comprises: The charging device obtains input power by connecting to a power adapter; The charging device acquires a charging current value supported by the battery by connecting to the battery, and the charging current value is less than a preset current threshold; The charging device determines that the power adapter supports a third charging mode; Based on the third charging mode, the charging device keeps the first switch, the second switch, the third switch and the fourth switch disconnected, closes the fifth switch and disconnects the sixth switch in a first time period, and charges the second energy storage element through the input power supply, and disconnects the fifth switch and closes the sixth switch in a second time period after the first time period, and charges the battery through the discharge of the second energy storage element.

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