Output method based on wireless power transmission

Abstract

The invention provides an output method based on wireless power transmission. The method comprises the following steps: firstly, acquiring an output end power parameter and a power output mode of the WPT system for LCC-LCC compensation, determining a corresponding circuit attribute parameter according to the type of the power output mode, further determining a first conduction angle and determining a currently generated impedance according to the corresponding circuit attribute parameter, and then adjusting a second conduction angle according to the first conduction angle to obtain a second conduction angle; and the impedance generated by the controllable capacitor module and the impedance generated by the half-bridge rectifier module are mutually counteracted, so that power capable of being stably output is obtained, and the power capable of being stably output is transmitted to external equipment. According to the invention, the wide alignment tolerance range of the coil can be enlarged, and the anti-offset capability of the coil is improved.

Description

Technical Field

[0001] The present invention relates to the field of power transmission, and more particularly, to an output method based on wireless power transmission. Background Art

[0002] Currently, in the prior art, for a wireless charging compensation topology with constant current output to achieve constant voltage output, it can be accomplished by using a switching tube to switch, which increases the volume of the device, the power loss of the system, and the cost. Or by controlling the primary side inverter or the secondary side active bridge to achieve constant voltage, but this method will bring more reactive power due to the large change in the phase shift angle, the phase shift angle range is limited, and the ability to adjust the load is limited. Currently, wireless charging mostly adopts the method of switching from constant current to constant voltage. However, heat problems will occur during constant current charging. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0004] To this end, a first aspect of the present invention proposes an output method based on wireless power transmission.

[0005] In view of this, a first aspect of the present invention provides an output method based on wireless power transmission, including: obtaining power parameters of the output end, where the power parameters of the output end include the output end voltage and the output end current; obtaining the power output mode, and based on the power output mode, obtaining circuit attribute parameters; based on the circuit attribute parameters, determining a first conduction angle of the half-bridge rectification module; based on the first conduction angle, adjusting a second conduction angle of the controllable capacitance module to obtain stable output power; and outputting the stable output power to an external device.

[0006] In addition, the output method based on wireless power transmission provided in the above technical solution of the present invention may further have the following additional technical features: In some technical solutions of the present invention, optionally, obtaining the power output mode and, based on the power output mode, obtaining circuit attribute parameters includes: determining the power output mode, where the power output mode includes constant power output, constant voltage output, and constant current output; if the power output mode is constant power output, obtaining the output end power and the load resistance value; if the power output mode is constant voltage output, obtaining the load resistance value.

[0007] In some technical solutions of the present invention, optionally, based on the circuit attribute parameters, determining the first conduction angle of the half-bridge rectification module includes: if the power output mode is constant power output, obtaining an equivalent resistance value based on the output end power; and obtaining the first conduction angle based on the equivalent resistance value and the load resistance value.

[0008] In some technical solutions of the present invention, optionally, adjusting the second conduction angle of the controllable capacitance module based on the first conduction angle includes: determining an impedance compensation value based on the first conduction angle; adjusting the second conduction angle based on the impedance compensation value.

[0009] In some technical solutions of the present invention, optionally, determining the first conduction angle of the half-bridge rectification module based on circuit attribute parameters includes: if the power output mode is constant voltage output, obtaining the value of the equivalent resistance based on the voltage at the output terminal; obtaining the first conduction angle based on the value of the equivalent resistance and the value of the load resistance.

[0010] In some technical solutions of the present invention, optionally, adjusting the second conduction angle of the controllable capacitance module based on the first conduction angle includes: determining an impedance compensation value based on the first conduction angle; adjusting the second conduction angle based on the impedance compensation value.

[0011] Additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, wherein: Figure 1 FIG. is one of the flowcharts of an output method based on wireless power transfer according to an embodiment of the present invention.

[0013] Figure 2 FIG. is one of the circuit diagrams of a bilateral LCC topology circuit according to an embodiment of the present invention; Figure 3 FIG. is one of the equivalent circuit diagrams of a bilateral LCC topology circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0014] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below with reference to the drawings and specific embodiments. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments may be combined with each other.

[0015] Many specific details are set forth in the following description in order to fully understand the present invention. However, the present invention may be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0016] The following refers to Figure 1 Describe an output method based on wireless power transfer according to some embodiments of the present invention.

[0017] AsFigure 1 As shown in the figure, the first aspect of the present invention provides an output method based on wireless power transmission, including: Step 102, obtaining the power parameters of the output end, where the power parameters of the output end include the output voltage and the output current of the output end; Step 104, obtaining the power output mode, and based on the power output mode, obtaining the circuit attribute parameters; Step 106, determining the first conduction angle of the half-bridge rectification module based on the circuit attribute parameters; Step 108, adjusting the second conduction angle of the controllable capacitor module based on the first conduction angle to obtain stable output power; Step 110, outputting the stable output power to an external device.

[0018] The present invention provides an output method based on wireless power transmission for a bilateral LCC topology circuit with a constant current output characteristic. Among them, as Figure 2 shown, the transmitting end of the bilateral LCC topology circuit is provided with a full-bridge rectification circuit, and the receiving end of the bilateral LCC topology circuit is provided with a half-bridge rectification module and a controllable capacitor module. When wireless charging is performed, the power supply output from the receiving end to the device usually generates impedance. Then, in order to eliminate the impedance to achieve constant voltage or constant power output. First, when the WPT system transmits energy, it obtains the power parameters of the output end and the power output mode of the LCC-LCC compensated WPT system, and confirms the corresponding circuit attribute parameters according to the type of the power output mode. Further, it determines the first conduction angle of the half-bridge rectification module according to the corresponding circuit attribute parameters, and realizes the stable output power through the first conduction angle. However, at the same time, by adjusting the half-bridge rectification module, impedance will also be generated. According to the first conduction angle, the currently generated impedance is confirmed, and then the adjustable capacitor module is adjusted according to the first conduction angle, that is, the second conduction angle of the adjustable capacitor module is adjusted, and then the controllable capacitor module is used for adjustment and compensation, so as to obtain the power that can be stably output, and transmit the stably output power to an external device. Through the present invention, the wide alignment tolerance range of the coil can be increased, and the anti-offset ability of the coil can be improved.

[0019] It should be noted that LCC stands for "Leading Common Collector", that is, "pilot common emitter", and it is still applicable to other topologies.

[0020] It should be noted that the WPT system, that is, the abbreviation of the Wireless Power Transmission (wireless power transmission) system, is a technology that directly transmits electrical energy to a load through space without wires or other physical connections.

[0021] It can be understood that the half-active rectifier bridge and the resistive load can be represented by an equivalent fundamental wave impedance as Among them, is the equivalent fundamental wave impedance, is the real part of the equivalent fundamental wave impedance, is the imaginary part of the equivalent fundamental wave impedance, is the resistance value of the load at the receiving end of the bilateral LCC topology circuit. If you want to eliminate the generated equivalent fundamental wave impedance, you can derive the real part of the equivalent fundamental wave impedance based on the resistance value at the receiving end of the bilateral LCC topology circuit, and then adjust the second conduction angle of the controllable capacitor module to achieve impedance elimination.

[0022] Furthermore, in some embodiments of the present invention, the power output method is obtained, and based on the power output method, circuit attribute parameters are obtained, including: determining the power output method, where the power output method includes constant power output, constant voltage output, and constant current output; if the power output method is constant power output, obtain the output power and the load resistance value; if the power output method is constant voltage output, obtain the load resistance value.

[0023] In this embodiment, the present invention adopts different processing methods according to different power output methods. Among them, the power output methods include constant power output, constant voltage output, and constant current output.

[0024] Among them, when the power output method is constant power output, obtain the output power and the load resistance value. The formula for obtaining the output power is , where is the output power, is the shunt compensation capacitor at the transmitting section, is the shunt compensation capacitor at the receiving section, is the mutual inductance, is the angular frequency of the full-bridge rectifier circuit with 4 MOSFET switches S1 to S4, is the AC voltage of the full-bridge rectifier circuit, is the real part of the equivalent fundamental wave impedance. Among them, when the power output method is constant voltage output, obtain the load resistance value. According to different circuit output methods, different parameters are obtained to facilitate subsequent adjustment.

[0025] It should be noted that since the present invention is used for a bilateral LCC topology circuit with a constant current output characteristic, if the power output method is constant current output, it can be directly output without additional processing.

[0026] Furthermore, in some embodiments of the present invention, based on the circuit attribute parameters, determine the first conduction angle of the half-bridge rectifier module, including: if the power output method is constant power output, based on the output power, obtain the equivalent resistance value; based on the equivalent resistance value and the load resistance value, obtain the first conduction angle.

[0027] In this embodiment, when the power output mode is constant power output, the equivalent resistance value is obtained according to the power at the output end. The formula for obtaining the equivalent resistance value is , where is the equivalent resistance value. On this basis, according to under the premise of the calculation formula, substituting the equivalent resistance value (or the formula for obtaining the equivalent resistance value) and the load resistance value into the formula, the first conduction angle of the half-bridge rectifier circuit can be obtained, that is , where is the first conduction angle of the half-bridge rectifier circuit in the constant power output state. According to the first conduction angle, different mutual inductances and load resistance values generated in different circuits can all achieve constant power output.

[0028] It should be noted that in the present invention, is the real part of the equivalent fundamental wave impedance, is the imaginary part of the equivalent fundamental wave impedance, and the formula separates the real part and the imaginary part for representation. Therefore, according to the formula, it can be clearly and indisputably seen that the calculation formula for is

[0029] Furthermore, in some embodiments of the present invention, based on the first conduction angle, adjusting the second conduction angle of the controllable capacitance module includes: determining an impedance compensation value based on the first conduction angle; adjusting the second conduction angle based on the impedance compensation value.

[0030] In this embodiment, since adjusting the half-bridge rectifier circuit generates a corresponding impedance, according to the determined first conduction angle, the impedance generated by the half-bridge rectifier circuit can be determined, and then according to the impedance value, the value to be compensated, that is, the impedance compensation value, can be confirmed. The present invention uses the controllable capacitance module to adjust the capacitance. Correspondingly, the adjustment compensation is achieved by changing the second conduction angle of the controllable capacitance module. Among them, as Figure 3 shown, the capacitance value can be calculated as , is the equivalent capacitance value. And the expression of the capacitance value of the controllable capacitance module is , where is the capacitance value of the controllable capacitance module, is the second conduction angle, is Figure 2 in the capacitance value. The impedance generated by the half-bridge rectifier circuit is offset by the controllable capacitance module, thereby achieving constant power output.

[0031] Further, in some embodiments of the present invention, determining a first conduction angle of the half-bridge rectification module based on circuit attribute parameters includes: if the power output mode is constant voltage output, obtaining the equivalent resistance value based on the output terminal voltage; obtaining the first conduction angle based on the equivalent resistance value and the load resistance value.

[0032] In this embodiment, if the power output mode is constant voltage output, the equivalent resistance value is obtained, and the first conduction angle is obtained according to the equivalent resistance value and the load resistance value. When the power output mode is constant power output, the equivalent resistance value is obtained according to the output terminal voltage. Among them, the formula for obtaining the equivalent resistance value is , where is the output terminal voltage.

[0033] On this basis, according to under the premise of the obtaining formula, substituting the equivalent resistance value (or the formula for obtaining the equivalent resistance value) and the load resistance value into the formula, the first conduction angle of the half-bridge rectification circuit can be obtained, that is , where is the first conduction angle of the half-bridge rectification circuit in the constant voltage output state. According to the first conduction angle, different mutual inductances and load resistance values generated in different circuits can all achieve constant voltage output.

[0034] Further, in some embodiments of the present invention, adjusting the second conduction angle of the controllable capacitance module based on the first conduction angle includes: determining an impedance compensation value based on the first conduction angle; adjusting the second conduction angle based on the impedance compensation value.

[0035] In this embodiment, in this embodiment, since adjusting the half-bridge rectification circuit generates corresponding impedance, according to the determined first conduction angle, the impedance generated by the half-bridge rectification circuit can be determined, and then according to the impedance value, the value to be compensated, that is, the impedance compensation value, can be confirmed. The present invention uses the controllable capacitance module to adjust the capacitance. Accordingly, the adjustment compensation is carried out by changing the second conduction angle of the controllable capacitance module. Among them, as Figure 3 shown, the capacitance value can be calculated as , is the equivalent capacitance value. And the expression of the capacitance value of the controllable capacitance module is , where is the capacitance value of the controllable capacitance module, is the second conduction angle, is Figure 2 in the capacitance value. The impedance generated by the half-bridge rectification circuit is cancelled by the controllable capacitance module, thereby realizing constant voltage output.

[0036] One of the embodiments of the present invention is described as follows: Test the output voltage and output current of the receiving end of the bilateral LCC topology circuit, and then confirm whether constant power output is required. If constant power output is required, obtain the power at the output end and the resistance value of the load resistor According to the power at the output end calculate the equivalent load resistance value of the half-bridge rectification module Then, according to the equivalent load resistance value and the resistance value of the load resistor obtain the first conduction angle of the half-bridge rectification circuit in the constant power output state Then, use the controllable power supply module to adjust to eliminate the generated impedance; if constant voltage output is required, obtain the resistance value of the load resistor According to the output voltage at the output end calculate the equivalent load resistance value of the half-bridge rectification module Then, according to the equivalent load resistance value and the resistance value of the load resistor obtain the first conduction angle of the half-bridge rectification circuit in the constant power output state Then, use the controllable power supply module to adjust to eliminate the generated impedance; if constant current output is required, since the present invention is used for a bilateral LCC topology circuit with a constant current output characteristic, it can be directly output without additional processing.

[0037] In the claims, the description and the accompanying drawings of the present invention, the term "a plurality of" means two or more, unless otherwise clearly defined. The orientation or positional relationship indicated by terms such as "upper", "lower", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for more convenient description of the present invention and to make the description process simpler, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, so these descriptions should not be construed as limitations on the present invention; terms such as "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection between multiple objects, or a detachable connection between multiple objects, or an integral connection; it can be a direct connection between multiple objects, or an indirect connection between multiple objects through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances of the above data.

[0038] In the claims, the specification and the drawings of the present invention, the descriptions of the terms "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In the claims, the specification and the drawings of the present invention, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0039] The foregoing are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An output method based on wireless power transmission, characterized in that: include: Acquiring output terminal power parameters, wherein the output terminal power parameters include output terminal voltage and output terminal current; Acquire a power output mode, and acquire circuit attribute parameters based on the power output mode; Based on the circuit property parameters, determining a first conduction angle of the half-bridge rectifier module; Based on the first conduction angle, adjusting the second conduction angle of the controllable capacitor module to obtain stable output power; The stabilized output power is output to an external device.

2. The output method based on wireless power transmission according to claim 1, characterized in that: The obtaining of the power output mode, and obtaining circuit attribute parameters based on the power output mode, includes: Determining the power output mode, wherein the power output mode includes constant power output, constant voltage output and constant current output; If the power output mode is constant power output, obtaining the output power and the load resistance value; If the power output mode is constant voltage output, the load resistance value is obtained.

3. The output method based on wireless power transmission according to claim 2, characterized in that: The determining a first conduction angle of the half-bridge rectifier module based on the circuit property parameter includes: If the power output mode is the constant power output, obtaining the equivalent resistance value based on the output end power; The first conduction angle is obtained based on the equivalent resistance value and the load resistance value.

4. The output method based on wireless power transmission according to claim 3, characterized in that: The adjusting the second conduction angle of the controllable capacitor module based on the first conduction angle includes: determining an impedance compensation value based on the first conduction angle; Based on the impedance compensation value, the second conduction angle is adjusted.

5. The output method based on wireless power transmission according to claim 2, characterized in that: The determining a first conduction angle of the half-bridge rectifier module based on the circuit property parameter includes: If the power output mode is the constant voltage output, obtaining the equivalent resistance value based on the output terminal voltage; The first conduction angle is obtained based on the equivalent resistance value and the load resistance value.

6. The output method based on wireless power transmission according to claim 3, characterized in that: The adjusting the second conduction angle of the controllable capacitor module based on the first conduction angle includes: determining an impedance compensation value based on the first conduction angle; Based on the impedance compensation value, the second conduction angle is adjusted.

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