TWI897531B - Power adjustment device and charging system - Google Patents

Abstract

A charging system includes a first device; a second device; and a power adjustment device including a DC-to-DC conversion unit; and a micro-control unit for receiving a charging instruction, a first power information of the first device and a second power information of the second device and performing the following steps: controlling the DC-to-DC conversion unit to convert a first supply current received by the first device into a first charging current according to the first power information and the second power information when the charging instruction instructs the first device to charge the second device; and controlling the DC-to-DC conversion unit to convert a second supply current received by the second device into a second charging current according to the first power information and the second power information when the charging instruction instructs the second device to charge the first device.

Description

Power conditioning devices and charging systems

The present invention relates to a power regulating device and a charging system, and in particular to a power regulating device and a charging system capable of bidirectional charging and discharging.

With the increasing popularity of electric vehicles, the application of light electric vehicles (LEVs) has also gained attention, including electric bicycles, electric motorcycles, electric wheelchairs, and golf carts. Currently, the development of LEVs is limited by battery capacity, which in turn limits their range. Therefore, more batteries need to be connected in parallel to increase capacity. For example, LEVs can be equipped with a main battery (master battery) and one or more auxiliary batteries to increase range. However, current LEVs can only charge the main and auxiliary batteries via AC chargers and cannot be directly charged using external batteries or other external power supplies. Furthermore, the main and auxiliary batteries in LEVs cannot directly provide power to charge external batteries or other external devices.

Therefore, how to manage the power of external devices, primary batteries, and auxiliary batteries, as well as control the bidirectional charging and discharging of external devices, primary batteries, and auxiliary batteries, has become one of the goals that the industry is striving for.

One of the main objectives of the present invention is to provide a power conditioning device and charging system to solve the above-mentioned problems.

The present invention provides a charging system, comprising a first device; a second device; and a power regulating device, wherein the power regulating device comprises a DC-DC conversion unit coupled to the first device and the second device; and a microcontroller coupled to the DC-DC conversion unit, the first device, and the second device, for receiving a charging instruction, first power information of the first device, and second power information of the second device, and executing the following steps: when the charging instruction instructs the first device to charge the second device, When charging the second device, the DC-DC conversion unit is controlled to convert a first supply current received by the first device into a first charging current to charge the second device based on the first power information and the second power information. Furthermore, when the charging instruction instructs the second device to charge the first device, the DC-DC conversion unit is controlled to convert a second supply current received by the second device into a second charging current to charge the first device based on the first power information and the second power information.

The present invention provides a power regulating device for a first device and a second device. The power regulating device includes a DC-DC conversion unit coupled to the first device and the second device; and a microcontroller coupled to the DC-DC conversion unit, the first device, and the second device. The microcontroller receives a charging instruction, first power information of the first device, and second power information of the second device, and performs the following steps: when the charging instruction instructs the first device to charge the second device, During charging, the DC-DC conversion unit is controlled to convert a first supply current received from the first device into a first charging current to charge the second device based on the first power information and the second power information. Furthermore, when the charging instruction instructs the second device to charge the first device, the DC-DC conversion unit is controlled to convert a second supply current received from the second device into a second charging current to charge the first device based on the first power information and the second power information.

1, 2, 3, 4, 7: Charging system

5, 6: Process

10: First device

12, 22, 16, 24, 28: Battery modules

14: AC to DC transformer

18: PD charger

20: Second device

30: Power regulation device

301: DC-DC conversion unit

302: Microcontroller unit

303, 304: Detection Unit

305: DC control circuit

306: Voltage and current measurement circuit

3031: Power Sensing Circuit

3032: Voltage sensing circuit 3032

S500, S502, S504, S506: Steps

Figure 1 is a schematic diagram of a charging system according to an embodiment of the present invention.

Figure 2 is a schematic diagram of another charging system according to an embodiment of the present invention.

Figure 3 is a schematic diagram of another charging system according to an embodiment of the present invention.

Figure 4 is a schematic diagram of another charging system according to an embodiment of the present invention.

Figure 5 is a flow chart of the charging method according to the first embodiment of the present invention.

Figure 6 is a flow chart of another charging method according to an embodiment of the present invention.

Figure 7 is a schematic diagram of another charging system according to an embodiment of the present invention.

Certain terms are used in this specification and the subsequent patent claims to refer to specific components. It should be understood by those skilled in the art that hardware manufacturers may use different terms to refer to the same component. This specification and the subsequent patent claims do not distinguish components by difference in name, but rather by difference in function. Throughout this specification and the subsequent patent claims, the word "including" is an open term and should be interpreted as "including but not limited to". In addition, the word "coupled" is used herein to include any direct and indirect electrical connection means. Therefore, if the text describes a first device coupled to a second device, it means that the first device can be directly electrically connected to the second device, or indirectly electrically connected to the second device through other devices or connection means.

Please refer to Figure 1, which is a schematic diagram of a charging system 1 according to an embodiment of the present invention. Charging system 1 includes a first device 10, a second device 20, and a power conditioning device 30. The power conditioning device 30 is coupled to the first device 10 and the second device 20 to control the discharge of the first device 10 to charge the second device 20, or to control the discharge of the second device 20 to charge the first device 10. Specifically, the power conditioning device 30 includes a DC-DC converter unit 301 and a microcontroller unit 302. The microcontroller unit 302 is coupled to the first device 10, the second device 20, and the DC-DC converter unit 301 to receive a charging command, first power information from the first device 10, and second power information from the second device 20. The charging instruction can instruct the first device 10 to discharge in order to charge the second device 20, or instruct the second device 20 to discharge in order to charge the first device 10. It should be noted that the charging instruction can be input by a user through a user interface (not shown in FIG. 1 ), or generated by a controller (not shown in FIG. 1 ) of the first device 10, the second device 20, or the power conditioning device 30, without limitation. In this way, the microcontroller 302 can perform the following steps: when a charging instruction instructs the first device 10 to charge the second device 20, the microcontroller 302 controls the DC-DC converter 301 to convert a first supply current received by the first device 10 into a first charging current to charge the second device 20 based on the first power information and the second power information; and when a charging instruction instructs the second device 20 to charge the first device 10, the microcontroller 302 controls the DC-DC converter 301 to convert a second supply current received by the second device 20 into a second charging current to charge the first device 10 based on the first power information and the second power information. In short, the first device 10 and the second device 20 can charge or discharge each other through the power conditioning device 30 of the present invention, i.e., bidirectional charging and discharging.

It should be noted that Figure 1 is merely an example embodiment of the present invention. Those skilled in the art will be able to adjust the system appropriately based on system requirements. For example, the charging system of the present invention can be applied to an electric power-assisted bicycle, but this is not a limitation. Any charging system requiring bidirectional charging and discharging capabilities falls within the scope of the present invention. For ease of explanation, the following embodiments illustrate the charging system as being applied to an electric power-assisted bicycle.

In one embodiment, please refer to FIG. 2 , which is a schematic diagram of a charging system 2 according to an embodiment of the present invention. In the charging system 2, the first device 10 may be a first battery module 12 , for example, a main battery module of an electric-assisted bicycle; the second device 20 may be a second battery module 22 , for example, an auxiliary battery module of an electric-assisted bicycle. The microcontroller 302 may communicate with the first battery module 12 and the second battery module 22 via a communication interface to receive first power information and second power information. The first power information may include a first battery voltage and a first battery current of the first battery module 12 , and the second power information may include a second battery voltage and a second battery current of the second battery module 22 , but the present invention is not limited thereto. Specifically, the microcontroller 302 can determine the battery capacity of the first battery module 12 and the battery capacity of the second battery module 22 based on the charging instruction, the first power information, and the second power information, and further determine a charging power or a discharging power. In this way, the microcontroller 302 can control the first battery module 12 and the second battery module 22 to charge and discharge each other at the charging power or the discharging power. It should be noted that the communication interface can be an integrated circuit ( ^IC ), a universal asynchronous receiver/transmitter (UART), or a controller area network (CAN), but is not limited to these. In addition, automotive communication protocols such as integrated circuits, universal asynchronous receiver/transmitters, and controller area networks are well known in the art and will not be elaborated on.

In another embodiment, please refer to FIG. 3 , which is a schematic diagram of a charging system 3 according to an embodiment of the present invention. In the charging system 3, the first device 10 may be an AC-to-DC converter 14, such as a dedicated charger for an electric power-assisted bicycle, or other charger that complies with the Universal Serial Bus (USB) Power Delivery (PD) standard or the Quick Charge (QC) standard. The second device 20 may be a second battery module 22, such as a main battery module, an auxiliary battery module, or a combination of a main battery module and an auxiliary battery module of the electric power-assisted bicycle. Specifically, if the AC/DC converter 14 is a dedicated charger for an electric power-assisted bicycle, the micro-control unit 302 can communicate with the AC/DC converter 14 and the second battery module 22 via a communication interface to receive first power information and second power information. The first power information may include, but is not limited to, an output power of the AC/DC converter 14, and the second power information may include, but is not limited to, a second battery voltage and a second battery current of the second battery module 22. On the other hand, if the AC/DC converter 14 is not a dedicated charger for an electric power-assisted bicycle, the AC/DC converter 14 may not have a communication function, meaning it will not provide the first power information to the micro-control unit 302. Therefore, the power conditioning device 30 of the charging system 3 may further include a first detection unit 303 coupled between the AC-DC converter 14 and the micro-control unit 302. The first detection unit 303 may be used to detect first power information of the AC-DC converter 14, such as, but not limited to, output power. In this way, the micro-control unit 302 may determine the charging power or discharging power based on the first power information (output power) and the second power information, and control the AC-DC converter 14 to charge the second battery module 22. Furthermore, the micro-control unit 302 may transmit second power information (second battery voltage and second battery current) of the second battery module 22 to the AC-DC converter 14. In this way, the AC-DC converter 14 can charge the second battery module 22 with an appropriate input power based on the second power information. For example, a charger compliant with the USB power transfer standard may have an output voltage of 5V, 9V, 15V, 20V, 28V, 36V, or 48V. The charger can charge the second battery module 22 at an output voltage suitable for the second battery module 22. In short, the charging system 3 can prevent the AC-DC converter 14 from charging the second battery module 22 with an inappropriate voltage, which could damage the second battery module 22.

It should be noted that the power conditioning device 30 of the present invention can also be used in scenarios where neither the first device 10 nor the second device 20 provides power information. In another embodiment, please refer to FIG. 4 , which is a schematic diagram of a charging system 4 according to an embodiment of the present invention. In charging system 4, the first device 10 can be a third battery module 16, for example, a mobile power supply that supports the USB power delivery standard or the Quick Charge standard; the second device 20 can be a fourth battery module 24, for example, a mobile device. In other words, charging system 4 can be used in scenarios where a mobile power supply and a mobile device charge and discharge each other via the power conditioning device 30. It should be noted that the third battery module 16 and the fourth battery module 24 may not provide their power information or may be unable to provide sufficient power information to the microcontroller 302. Therefore, as shown in FIG. 4 , the power conditioning device 30 of the charging system 4 may further include a first detection unit 303 coupled between the third battery module 16 and the micro-control unit 302, and a second detection unit 304 coupled between the fourth battery module 24 and the micro-control unit 302. The first detection unit 303 may be used to detect first power information of the third battery module 16, such as, but not limited to, output power. The second detection unit 304 may be used to detect second power information of the fourth battery module 24, such as, but not limited to, input power. In this way, the micro-control unit 302 can determine the charging power or discharging power according to the first power information (output power) and the second power information (input power), and control the third battery module 16 to charge the fourth battery module 24, or the fourth battery module 24 to charge the third battery module 16. In another embodiment, the third battery module 16 can be an automotive battery module or other battery modules with higher output voltages. For example, the third battery module 16 and the fourth battery module 24 can be 12V, 24V, 36V, 48V, 72V or 96V battery modules. The first detection unit 303 detects that the output voltage of the third module 16 is between 9.6V and 14.4V, and the second detection unit 303 detects that the output voltage of the third module 16 is between 9.6V and 14.4V. When the detection unit 304 detects that the output voltage of the fourth battery module 24 is between 28.8V and 43.2V, the microcontroller 302 determines that the third battery module 16 is a 12V battery module and the fourth battery module 24 is a 36V battery module. It then controls the DC-DC converter 301 to convert a suitable charging current to allow the third and fourth battery modules 16, 24 to charge and discharge each other. In short, even if the third and fourth battery modules 16, 24 are not dedicated battery modules for electric power-assisted bicycles, the power conditioning device 30 can still control the charging and discharging of the third and fourth battery modules 16, 24, and prevent damage to the third and fourth battery modules 16, 24 due to inappropriate charging specifications. Furthermore, it should be noted that, in addition to the different output voltages, the battery capacities of the third battery module 16 and the fourth battery module 24 may also differ.

The operation of charging systems 1-4 can be summarized as a charging method 5, as shown in Figure 5. Charging method 5 includes the following steps:

Step S500: Start.

Step S502: Detect or receive first power information of the first device and second power information of the second device.

Step S504: Control the first device and the second device to charge and discharge each other based on the first power information and the second power information.

Step S506: End.

For a detailed description of Process 5 and its derivative variations, please refer to the above description and will not be elaborated here.

It should be noted that charging systems 1-4 are different embodiments of the present invention, and those skilled in the art may make various modifications accordingly, without limitation. For example, the microcontroller 302 may also perform the following functions: controlling the first device 10 or the second device 20 to prioritize powering the electric-assisted bicycle's motor; controlling the first device 10 and the second device 20 to simultaneously power the electric-assisted bicycle's motor; controlling the first device 10 and the second device 20 to prioritize powering the first device 10 or the second device 20 with the higher output voltage, but the present invention is not limited thereto. For example, the microcontroller 302 may also perform the following functions: controlling the first device 10 to charge the second device 20 until the battery capacity of the second device 20 is fully charged; controlling the first device 10 and the second device 20 to charge and discharge each other so that the battery levels of the first device 10 and the second device 20 are balanced, but the present invention is not limited thereto. For example, the microcontroller 302 can control the first device 10 and the second device 20 to charge and discharge each other in a voltage-priority (CV) state, a current-priority (CC) state, or a power-priority (CP) state, but the present invention is not limited thereto. For example, if the first device 10 and the second device 20 are the main battery and the backup battery of an electric power-assisted bicycle, respectively, the microcontroller 302 can execute a charging method 6, as shown in FIG. 6 . Charging method 6 includes the following steps:

Step S600: Start. The user enters the charging command through the user interface.

Step S602: The primary battery is prioritized for power supply. The microcontroller 302 determines a first state of charge (SoC) of the primary battery. When the SoC is less than a first threshold (e.g., 0%), the output voltage of the backup battery is controlled to be equal to the current battery voltage of the backup battery. When the SoC is greater than or equal to the first threshold, the backup battery is not discharged.

Step S604: The backup battery is prioritized for power supply. The microcontroller 302 determines the backup battery's second state of charge (SOC). When the SOC is less than or equal to a second threshold (e.g., 0%), the output voltage of the primary battery is controlled to be equal to the primary battery's current voltage. When the SOC is greater than the second threshold, the primary battery is not discharged.

Step S606: The main battery and the backup battery provide power together. The microcontroller 302 determines the battery voltages of the main battery and the backup battery. When the battery voltage difference between the main battery and the backup battery is less than a third threshold value (e.g., 0.5V), the DC-DC converter 301 is controlled to be turned on. When the battery voltage difference between the main battery and the backup battery is greater than or equal to the third threshold value and the battery voltage of the main battery is greater than the battery voltage of the backup battery, the backup battery is not discharged. When the battery voltage difference between the main battery and the backup battery is greater than or equal to the third threshold value and the battery voltage of the main battery is less than or equal to the battery voltage of the backup battery, the main battery is not discharged.

Step S608: The main battery charges the backup battery. Set the backup battery to charge in a constant voltage (CV) priority mode or a constant current (CC) priority mode.

Step S610: The backup battery charges the main battery. Set the main battery to charge in a constant voltage (CV) priority mode or a constant current (CC) priority mode.

For detailed descriptions of Charging Method 6 and its derivative variations, please refer to the above description and will not be elaborated here.

It should be noted that the charging systems 1 to 4 only represent the necessary components required to implement the charging method 5. Their basic structure is well known in the art and therefore will not be described in detail. A person with ordinary skill in the art can appropriately add other components as needed. For example, as shown in FIG7 , FIG7 is a schematic diagram of a charging system 7 according to an embodiment of the present invention. In the charging system 7, the power conditioning device 30 controls a PD charger 18 (10) to discharge to charge the main battery 28 (20). The first detection unit 303 includes a power sensing circuit 3031 and a voltage sensing circuit 3032. In addition, the power conditioning device 30 also includes a DC control circuit 305 and a voltage and current sensing circuit 306. Specifically, when the power sensing circuit 3031 detects the PD charger 18, it determines the input power of the PD charger 18 and transmits it to the microcontroller 302 via the integrated circuit I ² C. Simultaneously, the primary battery 28 transmits its power information to the microcontroller 302 via the controller area network (CANBUS). Based on the PD charger 18 input power and the primary battery 28 power information, the microcontroller 302 instructs the voltage and current sensing circuit 306 and the DC control circuit 305 to control the DC-DC converter 301 to charge the primary battery 28 via the PD charger 18. The operating principles of the power sensing circuit 3031, the voltage sensing circuit 3032, the DC control circuit 305, and the voltage and current sensing circuit 306 are well known in the art and will not be described in detail.

It should be noted that charging systems 1 to 4 are embodiments of the present invention. A person of ordinary skill in the art can combine, modify or change the above-mentioned embodiments in accordance with the spirit of the present invention, without limitation thereto. All of the above descriptions, steps, and/or processes (including recommended steps) can be implemented through hardware, software, firmware (i.e., a combination of hardware devices and computer instructions, where the data in the hardware devices is read-only software data), electronic systems, or combinations of the above devices. Hardware can include analog, digital, and hybrid circuits (i.e., microcircuits, microchips, or silicon chips). Electronic systems can include system on chip (SoC), system in package (SiP), computer on module (CoM), and computer systems. The process steps and embodiments of the present invention may be stored in the form of program code or instructions in a storage unit. The storage unit may be a computer-readable recording medium, including, but not limited to, read-only memory (ROM), flash memory, random-access memory (RAM), a subscriber identity module (SIM), a hard drive, or a CD-ROM/DVD-ROM/BD-ROM. The above-described process steps and embodiments may be compiled into program code or instructions and stored in the storage unit. The microcontroller unit 302 can be used to read and execute the program code or instructions stored in the storage unit to implement all the aforementioned steps and functions.

In summary, in the charging system of the present invention, the power regulator detects or receives the charging specifications of the first and second devices and controls bidirectional charging and discharging of the first and second devices at appropriate charging specifications to prevent mutual damage. As a result, compared to prior art, the charging system of the present invention can support a wider range of charging devices and battery modules. The above description is merely a preferred embodiment of the present invention. All equivalent variations and modifications made within the scope of the patent application of this invention are intended to be covered by this invention.

1: Charging system 10: First device 20: Second device 30: Power conditioning device 301: DC-DC converter unit 302: Microcontroller unit

Claims (4)

A charging system for an electric power-assisted bicycle comprises: a first device; a second device; and a power conditioning device, wherein the power conditioning device comprises: a DC-DC converter unit coupled to the first device and the second device; and a microcontroller unit coupled to the DC-DC converter unit, the first device, and the second device, configured to receive a charging instruction, first power information from the first device, and second power information from the second device, and to perform the following steps: when the charging instruction instructs the first device to charge the second device, controlling the DC-DC converter unit to convert a first supply current received from the first device into a first charging current to charge the second device based on the first power information and the second power information; and When the charging instruction instructs the second device to charge the first device, the DC-DC conversion unit is controlled to convert a second supply current received by the second device into a second charging current to charge the first device based on the first power information and the second power information. The first device is an AC-DC converter, and the second device is a battery module. The AC-DC converter complies with a Universal Serial Bus (USB) Power Delivery (PD) standard or a Quick Charge (QC) standard. A charging system as described in claim 1, wherein the power conditioning device further includes a first detection unit coupled between the AC-DC transformer and the DC-DC conversion unit, and the first detection unit is used to detect the first power information; wherein the first power information includes an output power of the AC-DC transformer, and the second power information includes a battery voltage and a battery current of the battery module. A power conditioning device, provided on an electric power-assisted bicycle and used with a first device and a second device, comprises: A DC-DC conversion unit coupled to the first device and the second device; and A microcontroller unit coupled to the DC-DC conversion unit, the first device, and the second device, configured to receive a charging instruction, first power information from the first device, and second power information from the second device, and to perform the following steps: When the charging instruction instructs the first device to charge the second device, controlling the DC-DC conversion unit to convert a first supply current received from the first device into a first charging current to charge the second device based on the first power information and the second power information; and When the charging instruction instructs the second device to charge the first device, the DC-DC conversion unit is controlled to convert a second supply current received by the second device into a second charging current to charge the first device based on the first power information and the second power information. The first device is an AC-DC converter, and the second device is a battery module. The AC-DC converter complies with a Universal Serial Bus (USB) Power Delivery (PD) standard or a Quick Charge (QC) standard. A power regulating device as described in claim 3, wherein the power regulating device further includes a first detection unit coupled between the AC-to-DC transformer and the DC-to-DC conversion unit, and the first detection unit is used to detect the first power information; wherein the first power information includes an output power of the AC-to-DC transformer, and the second power information includes a battery voltage and a battery current of the battery module.