Patent Application
20230173934
The present invention relates generally to a charging device, and more particularly to a power converter and a charging system having the same that could charge a lithium iron phosphate (LiFePO4) battery.
In recent years, bicycle leisure activities have become popular and become a tool for leisure sports, and in addition to ordinary bicycles that rely solely on human pedaling as the driving force for forwarding movement, electric-assisted bicycles that assist human pedaling by an auxiliary motor are also another option for bicycle leisure activities with the development of technology. In other words, the user only needs to use a small pedaling force to cooperate with the auxiliary motor to drive the electric-assisted bicycle moving forward. Therefore, compared with ordinary bicycles, the electric-assisted bicycles allow the user to enjoy the fun of riding a bicycle less laboriously.
Considering an overall weight and size of the electric-assisted bicycle, a battery of the electric-assisted bicycle is usually not too large, which will limit the capacity of the battery. Additionally, the conventional electric-assisted bicycles need to be charged at home and cannot be charged outside, therefore the user always need to pay attention to the remaining capacity when riding the electric-assisted bicycle outside to avoid the dilemma of running out of electricity.
In view of the above, the primary objective of the present invention is to provide a power converter and a charging system having the same, which could increase a convenience of charging an electric-assisted bicycle outside.
The present invention provides a charging system adapted to charge a LiFePO4 battery, wherein the LiFePO4 battery has a connecting port. The charging system includes a charging station and a power converter, wherein the charging station includes a power output device. The power output device is adapted to output a first DC power having a first voltage. The power converter includes a housing and a converting device, wherein the housing has a battery socket that has an output connecting port and is adapted to be engaged with the LiFePO4 battery. The output connecting port is adapted to be detachably and electrically connected to the connecting port of the LiFePO4 battery. The converting device is disposed in the housing and is electrically connected to the power output device and the output connecting port. The converting device converts the first DC power into a second DC power and outputs the second DC power to the output connecting port for charging the LiFePO4 battery. The second DC power has a second voltage. The converting device steps down the first voltage to the second voltage.
The present invention further provides a power converter that is adapted to be connected to a charging station and to charge a LiFePO4 battery, wherein the charging station is adapted to output a first DC power that has a first DC voltage, and the LiFePO4 battery has a connecting port. The power converter includes a housing and a converting device, wherein the housing has a battery socket. The battery socket has an output connecting port and is adapted to be engaged with the LiFePO4 battery. The output connecting port is adapted to be detachably and electrically connected to the connecting port of the LiFePO4 battery. The converting device is disposed in the housing and is adapted to be electrically connected to the charging station and the output connecting port, wherein the converting device converts the first DC power into a second DC power and outputs the second DC power to the output connecting port to charge the LiFePO4 battery. The second DC power has a second voltage. The converting device steps down the first voltage to the second voltage.
With the aforementioned design, the power converter could convert the first DC power of the charging station with higher voltage into the second DC power with lower voltage, thereby the charging system of the present invention could charge the LiFePO4 battery that requires lower charging voltage, increasing a convenience of charging the electric-assisted bicycle outside.
The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which
A charging system 1 according to a first embodiment of the present invention is illustrated in
The charging system 1 includes a charging station 10 and a power converter 20, wherein the charging station 10 is adapted to supply power to an electric vehicle, such as an electric scooter or an electric car. The charging station 10 includes a body 12, a power output device 14, and a charging cable 16, wherein the power output device 14 is located in the body 12 and is adapted to output a first DC power having a first voltage and a first current. The power output device 14 converts an AC power to the first DC power. In the current embodiment, the voltage of the first DC power has an adjustable voltage range, and the first voltage is a minimum voltage in an adjustable voltage range. For instance, a maximum voltage of the adjustable voltage range is 100V, and a minimum voltage (i.e., the first voltage) is 50V. The power output device 14 could output different voltages and different currents to meet the charging voltages required by different electric vehicles.
The charging cable 16 is electrically connected to the power output device 14, and the first DC power is outputted by the charging cable 16. In the current embodiment, the charging cable 16 has a connecting port 162, wherein the connecting port 162 includes a communicating port 162a and a power port 162b. The power port 162b is electrically connected to the power output device 14 to output the first DC power.
The charging station 10 includes a communicating module (hereafter called a first communicating module 18), wherein the first communicating module 18 is electrically connected to the power output device 14 and the communicating port 162a of the charging cable 16. The first communicating module 18 takes a CAN-bus protocol as an example. The power output device 14 could communicate with an outside communicating module via the first communicating module 18. For instance, when the charging cable 16 is connected to an electric vehicle, the first communicating module 18 of the charging station 10 communicates with a communicating module of the electric vehicle, thereby obtaining a battery information of the electric vehicle, wherein the battery information includes a charging voltage required by the battery, a charging current required by the battery, etc. The power output device 14 determines a voltage and a current of the first DC power to be outputted based on the obtained battery information.
The power converter 20 is adapted to step down the first DC power to a second DC power, thereby charging the LiFePO4 battery 40 that requires a lower charging voltage. The power converter 20 includes a housing 22 and a converting device 28, wherein the housing 22 has a charging cable socket 24 and a battery socket 26. The charging cable socket 24 has an input connecting port 242 that could be detachably and electrically connected to the connecting port 162 in the charging cable 16. The input connecting port 242 has a communicating port 242a and a power port 242b, wherein when the charging cable 16 is engaged with the charging cable socket 24, the communicating port 162a and the power port 162b of the connecting port 162 of the charging cable 16 are respectively connected to the communicating port 242a and the power port 242b of the input connecting port 242.
The battery socket 26 has an output connecting port 262 and is adapted to be inserted by the LiFePO4 battery 40, wherein the output connecting port 262 is detachably and electrically connected to the connecting port 42 of the LiFePO4 battery 40. The output connecting port 262 has a communicating port 262a and a power port 262b, wherein when the LiFePO4 battery 40 is engaged with the battery socket 26, the communicating port 422 and the power port 424 of the connecting port 42 of the LiFePO4 battery 40 are respectively connected to the communicating port 262a and the power port 262b of the output connecting port 262.
The converting device 28 is disposed in the housing 22 and is electrically connected to the power output device 14 and the output connecting port 262. In the current embodiment, the converting device 28 is electrically connected to the power output device 14 via the input connecting port 242 and the charging cable 16.
The converting device 28 converts the first DC power to the second DC power and outputs the second DC power to the output connecting port 262, wherein the second DC power has a second voltage and a second current. The converting device 28 steps down the first voltage to the second voltage, so that the second voltage could be used as a charging voltage to the LiFePO4 battery 40. In the current embodiment, the converting device 28 includes a step-down module 30 and a charging circuit 36, wherein the step-down module 30 is electrically connected to the power port 242b of the input connecting port 242 and is adapted to step the first voltage down to the second voltage. The step-down module 30 includes an isolation transformer 32 and a step-down circuit 34, wherein the isolation transformer 32 is electrically connected to the power port 242b of the input connecting port 242 and is adapted to electrically isolate the high voltage of the charging station 10, thereby improving a safety of the power converter 20. The isolation transformer 32 steps down an electricity of the first DC power to a first predetermined DC power with a first predetermined voltage and outputs the first predetermined DC power to the step-down circuit 34, wherein the step-down circuit 34 is a buck circuit, which steps down the first predetermined voltage to a second predetermined DC power with a stable second predetermined voltage and outputs the second predetermined DC power to the charging circuit 36. The charging circuit 36 is a charging circuit in a constant-current constant-voltage (CC-CV) type and is electrically connected to the power port 262b of the output connecting port 262, wherein the charging circuit 36 converts the second predetermined DC power to the second DC power and outputs the second DC power to the power port 262b of the output connecting port 262. A maximum value of the second voltage of the second DC power is 43.8V, the second current (i.e., an output current) is 13.2 A, and the second current is twice the standard charging current of the LiFePO4 battery 40, thereby the LiFePO4 battery 40 could be charged twice as fast.
Additionally, the power converter 20 further includes a communicating module (hereafter called a second communicating module 38), wherein the second communicating module 38 is electrically connected to the converting device 28 and is electrically connected to the communicating port 242a of the input connecting port 242 and the communicating port 262a of the output connecting port 262 respectively. The second communicating module 38 takes a CAN-bus protocol as an example. The second communicating module 38 could communicate with the first communicating module 18 of the charging station 10 and the communicating module 44 of the LiFePO4 battery 40. In the current embodiment, the second communicating module 38 is electrically connected to the charging circuit 36 of the converting device 28.
While using the charging system 1, the user could choose to either first insert the charging cable 16 into the charging cable socket 24 (as shown in
Take the state shown in
Take the state shown in
During a process of charging (i.e., in a state when the converting device 28 outputs the second DC power), when the output connecting port 262 electrically connected to the connecting port 42 of the LiFePO4 battery 40 is changed to be not electrically connected to the connecting port 42 of the LiFePO4 battery 40, the converting device 28 stop outputting the second DC power to the output connecting port 262. In the current embodiment, either when the second communicating module 38 could not communicate with the communicating module 44 of the LiFePO4 battery 40 or when the charging circuit 36 detects that the power port 262b of the output connecting port 262 is not connected to the power port 424 of the LiFePO4 battery 40, the charging circuit 36 stops outputting the second DC power. In this way, a risk of electric shock when the LiFePO4 battery 40 is removed from the battery socket 26 during the charging process could be prevented. After that, the second communicating module 38 immediately sends a power stop command to the first communicating module 18 to make the power output device 14 stops outputting the first DC power, thereby preventing the high voltage of the charging station 10 from being continuously input to the power converter 20.
When a voltage of the LiFePO4 battery 40 is charged to a predetermined voltage, the converting device 28 stops outputting the second DC power to the output connecting port 262, and the second communicating module 38 sends the power stop command to the first communicating module 18 to make the power output device 14 stops outputting the first DC power. In the current embodiment, when the charging circuit 36 detects that the voltage of the LiFePO4 battery 40 reaches the predetermined voltage, the charging circuit 36 stops outputting the second DC power and send a charge complete command to the second communicating module 38, and the second communicating module 38 sends the power stop command to the first communicating module 18 to make the power output device 14 stops outputting the first DC power, thereby completing the charging of the LiFePO4 battery 40.
A charging system 2 according to a second embodiment of the present invention is illustrated in
When the charging cable 16 is connected to an electric vehicle, the power output device 50 outputs a third DC power to charge the electric vehicle via the second output port 504 through the charging cable 16.
With the aforementioned design, the power converter could convert the first DC power of the charging station with higher voltage into the second DC power with lower voltage, thereby the charging system of the present invention could charge the LiFePO4 battery that requires lower charging voltage, increasing a convenience of charging the electric-assisted bicycle outside.
It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention.
