Disclosure of Invention
A light energy charger comprising: the device comprises a photovoltaic module, a voltage conversion module, a charging module and a controller; the photovoltaic module is used for converting received solar energy into electric energy, the voltage conversion module is used for changing direct-current voltage, the charging module is used for outputting the electric energy to the battery pack, and the controller is at least used for controlling the charging module; the photovoltaic module is electrically connected with the voltage conversion module and the controller respectively; the voltage conversion module is electrically connected with the photovoltaic module, the charging module and the controller respectively; the charging module is electrically connected with the controller; the charging module can output power of at least 20W.
Further, the controller includes: a first control unit; the first control unit can control the charging current of the charging module according to a preset voltage of the photovoltaic module; the preset voltage is a voltage value corresponding to a maximum power point in a current-voltage characteristic curve of the photovoltaic module.
Further, the controller includes: a second control unit; the second control unit can control the charging current of the charging module according to the maximum power which can be provided by the photovoltaic module currently.
Further, the charging module is provided with more than two charging interfaces, and each charging interface can charge for one battery pack.
Further, the light energy charger further comprises: the alternating current module and the rectifying module; the alternating current module is used for receiving alternating current, and the rectifying module is used for converting the alternating current into direct current; the alternating current module is electrically connected with the rectification module, and the rectification module is electrically connected with the controller and the charging module.
Further, the controller includes: a third control unit; the third control unit can judge whether the alternating current module is connected with the alternating current power supply or not; the third control unit controls the charging module to output charging current by using the electric energy of the photovoltaic module when the alternating current module is not connected with the alternating current power supply; and the third control unit controls the charging module to output charging current by using the electric energy of the photovoltaic module and/or the alternating current module when the alternating current module is connected to the alternating current power supply.
Further, the light energy charger further comprises: a power supply module; the power supply module is used for supplying power to the controller; the power supply module is electrically connected with the controller.
Further, the photovoltaic module includes: a plurality of photovoltaic cells and a switching device; the photovoltaic units are provided with at least two terminals, and the switching device is arranged to enable the plurality of photovoltaic units to be switched between series connection and parallel connection; when the switching device is in a first state, the photovoltaic module has a first voltage; when the switching device is in the second state, the photovoltaic module has a second voltage.
Further, the light energy charger further comprises: a heat radiation fan and a heat radiation motor; the heat dissipation fan is used for dissipating heat, and the heat dissipation motor is used for driving the heat dissipation fan; the heat dissipation motor is powered by the electric energy generated by the photovoltaic module.
An electrical energy system comprising: a power tool and a light energy charger as described above.
Further, the electric power tool includes: a tool host and a battery pack; the tool host is used for realizing the tool function, the battery pack is used for supplying power to the tool host, and the battery pack can be charged through the charging module; the controller further includes: a fourth control unit; the fourth control unit is used for communicating with the battery pack; the fourth control unit controls the charging voltage of the charging module according to the rated voltage of the battery pack.
The light energy charger can charge the battery pack suitable for the electric tool, saves electric energy and reduces cost.
Detailed Description
The invention is described in detail below with reference to the figures and the embodiments.
The power system 100 shown in fig. 1 includes: a power tool 10 and a light energy charger 20, wherein the light energy charger 20 can charge the power tool 10 using solar energy.
The electric power tool 10 includes: a tool main body 11 and a battery pack 12, wherein the battery pack 12 is used for supplying power to the tool main body 11. The tool host 11 may include: an operating mechanism 111, a motor (not shown), a transmission mechanism (not shown), and a functional element (not shown). The operating mechanism 111 is used for a user to operate to use the electric tool 10, and the operating mechanism 111 may include: a handle for gripping by a user, a switch for actuating the power tool 10, and the like. The motor is used for converting the electric energy provided by the battery pack 12 into power output. The transmission mechanism is arranged between the motor and the functional part and used for transmitting the power output by the motor to the functional part and driving the functional part to move so as to realize the tool function. The function may be provided according to the type of the power tool 10, for example, in the present embodiment, the power tool 10 is a lawn mower, and correspondingly, the function may be a cutting blade.
Of course, the power tool 10 may also be other garden-type tools, such as a lawnmower, a pruner, a blower, etc.; the power tool 10 may also be a drill-type tool, such as an electric drill, screwdriver, multi-function tool, or the like; the power tool 10 may also be a saw-type tool, such as a circular saw, a jig saw, or the like; the power tool 10 may also be an abrasive type tool such as a sander, an angle grinder, or the like.
In essence, as long as the power tool 10 needs to be powered by the battery pack 12, and the battery pack 12 is charged by using the optical energy charger 20, the essence of the following technical solution can be adopted.
The battery pack 12 serves as an energy source of the power tool 10 for supplying power to the tool main body 11. The battery pack 12 includes: a battery pack housing 121, a cell element (not shown), and a battery pack interface 122. The battery pack case 121 forms an outer shell of the battery pack 12, and the battery pack case 121 is configured to be compatible with the tool main unit 11 and the optical charger 20, so that the battery pack 12 can be coupled to the tool main unit 11 or the optical charger 20. For a battery pack 12 suitable for use in the power tool 10, it is desirable that the number of cell elements in one battery pack 12 be at least 3, so that the battery pack 12 can have a rated voltage of at least 10.8V. The battery pack interface 122 can be electrically connected to the light energy charger 20 for introducing electrical energy output by the light energy charger 20 into the battery pack 12. The battery pack interface 122 can also be electrically connected to the tool host 11 for outputting the electric power stored in the battery pack 12 to the motor in the tool host 11 when the battery pack 12 is coupled to the tool host 11.
The light energy charger 20 is used to charge the battery pack 12, and the battery pack 12 can be detachably coupled to the light energy charger 20. Specifically, the optical charger 20 includes a photovoltaic module 21, the photovoltaic module 21 includes a plurality of photovoltaic units, the plurality of photovoltaic units are connected to output electric energy through two terminals, each photovoltaic unit may include a plurality of solar cells 211, each solar cell 211 includes a silicon material, and the silicon material can generate current under illumination.
The structure of the light energy charger 20 is described in detail below:
as shown in fig. 2, the optical charger 20 includes: photovoltaic module 21, voltage conversion module 22, charging module 23, controller 24, power supply module 25, ac module 26 and rectifier module 27.
The photovoltaic module 21 is electrically connected to the voltage conversion module 22, the controller 24 and the power supply module 25, respectively, and the photovoltaic module 21 is configured to convert the solar energy received by the light energy charger 20 into electric energy, and then output the electric energy through the voltage conversion module 22 and the charging module 23. The photovoltaic units in the photovoltaic module 21 may be connected in series or in parallel, or both, so as to realize different outputs of the photovoltaic module 21.
The voltage conversion module 22 is electrically connected to the photovoltaic module 21, the controller 24 and the charging module 23, respectively, and is configured to change the voltage output by the photovoltaic module 21 to adapt to the battery pack 12 to be charged. Specifically, the voltage conversion module may employ a direct current transformer, and more specifically, a DC-DC step-up transformer. As is known, the principle of photovoltaic conversion of the photovoltaic module 21 is to generate movable charges on a semiconductor by sunlight irradiation, thereby generating a potential difference. The converted current is direct current, and the directly output voltage is low, so that the voltage of the photovoltaic module 21 can be boosted, and a DC-DC boost transformer can be arranged.
The charging module 23 is used for outputting electric energy to the battery pack 12, and the charging module 23 is electrically connected to the voltage conversion module 22, the controller 24, the rectifying module 27 and the battery pack 12, respectively. During operation, the charging module 23 can be controlled by the controller 24 to transfer the electric energy output by the voltage conversion module 22 and/or the rectification module 27 to the battery pack 12. The charging module 23 can output power of at least 20W and can charge the battery pack 12 of 10.8V or more, even 36V or 56V.
The controller 24 is configured to control the charging module 23, and includes: a first control unit 241, a second control unit 242, a third control unit 243 and a fourth control unit 244.
The first control unit 241 can be electrically connected to the photovoltaic module 21 and the charging module 23, and the second control unit 242 can be electrically connected to the photovoltaic module 21 and the charging module 23. The controller 24 can control the charging current of the charging module 23 by setting and using the first control unit 241 or the second control unit 242.
It is known that the amount of power output by the light energy charger 20 varies, and it is desirable to use the light energy charger 20 with maximum efficiency. To this end, we can provide a first control unit 241 or a second control unit 242 in the controller 24.
When the first control unit 241 is disposed in the controller 24, the first control unit 241 can control the charging current of the charging module 23 according to a preset voltage of the photovoltaic module 21, where the preset voltage is a voltage value corresponding to a maximum power point in a current-voltage characteristic curve of the photovoltaic module 21. Specifically, the first control unit 241 obtains the preset voltage according to the current-voltage characteristic curve of the photovoltaic module 21, and then controls the photovoltaic module 21 to output the preset voltage and adjust the charging current of the charging module 23 in real time until the charging current can maximize the power output by the photovoltaic module 21 under the condition of the preset voltage.
When the second control unit 242 is provided in the controller 24, the charging current may be controlled by using another method different from the control method of the first control unit 241, that is, the second control unit 242 may control the charging current of the charging module 23 according to the maximum power that the photovoltaic module 21 can currently provide. Specifically, the second control unit 242 can adjust the charging current of the charging module 23 in real time until the charging current is adjusted so that the power currently output by the photovoltaic module 21 reaches the maximum.
The third control unit 243 is used to control the ac module 26 and the rectifier module 27, and the ac module 26 and the rectifier module 27 are arranged so that the light energy charger 20 can also charge with the utility grid when the illumination intensity is insufficient. Specifically, the ac module 26 is used for introducing ac power, and may be connected to an external utility grid, the ac module 26 is further electrically connected to a rectifier module 27, the rectifier module 27 is electrically connected to the controller 24 and the charging module 23, the rectifier module 27 is used for converting the ac power introduced by the ac module 26 into dc power that can be supplied to the battery pack 12, and in order to be adapted to the battery pack 12, the rectifier module 27 may further include a voltage boost circuit.
The third control unit 243 can determine whether the ac module 26 is connected to the ac power source. When the ac module 26 is not connected to the ac power source, the third control unit 243 controls the charging module 23 to output the charging current by using the electric energy of the photovoltaic module 21; when the ac module 26 is connected to the ac power source, the third control unit 243 controls the charging module 23 to output the charging current by using the electric energy of the photovoltaic module 21 and/or the ac module 26.
For example, a first preset power and a second preset power may be stored in the third control unit 243, and the first preset power is greater than the second preset power. The third control unit 243 can determine the magnitude relationship between the power output by the photovoltaic module 21 and the stored first preset power and second preset power. Specifically, when the ac module 26 is connected to an ac power supply, the third control unit 243 determines whether the power output by the photovoltaic module 21 at this time is greater than or equal to a first preset power, and if the power output by the photovoltaic module 21 is greater than or equal to the first preset power, the third control unit 243 may control the charging module 23 to output the charging current only by using the electric energy of the photovoltaic module 21 at this time; if the power output by the photovoltaic module 21 is smaller than the first preset power, then the third control unit 243 determines whether the power output by the photovoltaic module 21 is greater than or equal to the second preset power, and if the power output by the photovoltaic module 21 is greater than or equal to the second preset power, then the third control unit 243 controls the charging module 23 to output the charging current by using the electric energy of the photovoltaic module 21 and the alternating current module 26; if the power output by the photovoltaic module 21 is less than the second preset power, the third control unit 243 controls the charging module 23 to output the charging current only by using the electric energy of the ac module 26. Therefore, the energy source of the charging module 23 is intelligently controlled, so that the solar energy can be effectively utilized, the energy is saved, and the cost is reduced on the premise that the battery pack 12 is charged fully for the user to use.
The power supply module 25 is used for supplying power to the controller 24, and the power supply module 25 is respectively connected with the photovoltaic module 21 and the controller 24, so that the power supply module 25 can supply power to the controller 24 by using the electric energy output by the photovoltaic module 21.
As shown in fig. 3, the charging module 23 includes a charging interface 231 adapted to the battery pack interface 122 of the battery pack 12. For one optical energy charger 20, more than two charging interfaces 231 may be included, and each charging interface 231 can charge one battery pack 12, so that the optical energy charger 20 can charge more than two battery packs 12 at the same time.
Each charging interface 231 may include three terminals: a positive terminal, a negative terminal and a communication terminal. The positive terminal and the negative terminal are respectively butted against the positive electrode and the negative electrode of the battery pack interface 122, so that electric energy can be output from the charging interface 231 to the battery pack 12. The communication terminal is used for connecting with the communication terminal in the battery pack interface 122, and the battery pack 12 is further connected with the fourth control unit 244 of the controller 24 through the communication terminal of the charging interface 231. The fourth control unit 244 can obtain the rated voltage of the battery pack 12 through communication connection with the battery pack 12, and the fourth control unit 244 can control the charging voltage of the charging module 23 according to the rated voltage after obtaining the rated voltage of the battery pack 12. The charging interface 231 may further include two terminals connected to the voltage conversion module 22 and the rectification module 27 in fig. 2, respectively.
As described above, a plurality of photovoltaic units may be included in the photovoltaic module 21, and different outputs may be realized by different connection relationships with each other. As shown in fig. 4, the photovoltaic module 21 may include three photovoltaic units: first photovoltaic unit 211, second photovoltaic unit 212 and third photovoltaic unit 213, each photovoltaic unit all is equipped with two terminals. Correspondingly, the photovoltaic module 21 further includes a switching device (not shown) for controlling switching between series connection and parallel connection between the photovoltaic units. The switching means may comprise: six control switches K1, K2, K3, K4, K5 and K6, all of which are connected to the controller 24. When the controller 24 controls the switches K1, K3, K4 and K6 to be turned on and the switches K2 and K5 to be turned off, the switches are connected in parallel, and the switching device is in a first state, and the photovoltaic module 21 has a first voltage; when the controller 24 controls the switches K1, K3, K4 and K6 to be turned off and K2 and K5 to be turned on, they are connected in series, and the switching device is in the second state, and the photovoltaic module 21 has the second voltage. In this way, the voltage output by the photovoltaic module 21 can be directly controlled by the switching device, thereby enabling the light energy charger 20 to be adapted to more battery packs 12.
As is known, when the light energy charger 20 and the battery pack 12 of the power tool 10 are placed outdoors for charging as shown in fig. 1, the temperature of the battery pack 12 rises relatively quickly with respect to the inside of the room, so that a heat dissipation fan (not shown) for dissipating heat from the battery pack 12 and a heat dissipation motor (not shown) for driving the heat dissipation fan may be provided in the light energy charger 20. The heat dissipation fan generates heat dissipation airflow to blow to the battery pack 12, and the heat dissipation motor can be directly powered by the electric energy generated by the photovoltaic module 21.
The foregoing illustrates and describes the principles, general features, and advantages of the present invention. It should be understood by those skilled in the art that the above embodiments do not limit the present invention in any way, and all technical solutions obtained by using equivalent alternatives or equivalent variations fall within the scope of the present invention.