Constant-voltage output type wireless electric energy and information synchronous transmission device and parameter design method thereof

Abstract

The invention discloses a constant-voltage output type wireless electric energy and information synchronous transmission device and a parameter design method thereof. The wireless electric energy and information synchronous transmission device comprises a transmitting side and a receiving side, the transmitting side is composed of a transmitting coil Lp1, a transmitting coil Lp2, an energy transmitting compensation topology, an information transmitting compensation topology, a direct-current power supply Up, an inverter circuit and an information modulation circuit, the direct-current power supply Up is connected with the inverter circuit, and the transmitting coil Lp1 is connected with the transmitting coil Lp2 in series; the receiving side is composed of a receiving coil Ls1, a receiving coil Ls2, an energy receiving compensation topology, an information receiving compensation topology, a rectification filter circuit and an information demodulation circuit, the receiving coil Ls1 and the receiving coil Ls2 are connected in series, and a rectification filter in the rectification filter circuit is connected with a load RL and a compensation capacitor C0. The enabling simultaneous information transmission system has the information transmission capacity, and meanwhile flexible adjustment of the output voltage value can be achieved through reasonable design of the compensation inductor Lf2.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless power and information synchronous transmission systems, and in particular relates to a constant voltage output type wireless power and information synchronous transmission device and a parameter design method thereof. Background Art

[0002] Wireless power transfer (WPT) technology, with its advantages of convenience, safety, and strong environmental adaptability, has been widely researched and applied in fields such as electric vehicles, industrial control, and medical equipment. It was selected as one of the top ten future research directions by the US magazine Technology Review. In practical engineering applications, WPT systems require not only an energy transmission channel but also an information transmission channel between the transmitter and receiver to achieve closed-loop control and information exchange. To suppress high-frequency interference from energy, existing simultaneous wireless power and data transfer (SWPDT) research is mostly based on the LCC-LCC compensation topology. This uses an LC low-pass filter composed of the LCC's series compensation inductor and parallel compensation capacitor to suppress high-frequency interference generated by the energy rectification and inversion processes. Under this structure, the WPT system can only achieve constant current (CC) output and cannot meet the requirements of constant voltage applications. Furthermore, due to the presence of series compensation, existing constant-voltage topologies such as LCC-S and S-LCC are unsuitable for SWPDT systems. This limitation in compensation topology significantly hinders the development of simultaneous energy and information transmission technology. Therefore, there is an urgent need to design a constant-voltage output wireless simultaneous power and information transmission device and its parameter design method to achieve efficient and stable transmission of energy and information under constant-voltage output. Summary of the Invention

[0003] The purpose of the present invention is to solve the problem of difficulty in achieving constant-voltage energy output in existing wireless power and information synchronous transmission systems due to limited compensation topology. A constant-voltage output wireless power and information synchronous transmission device and a parameter design method thereof are proposed to achieve efficient and stable transmission of energy and information under constant-voltage output of the system.

[0004] To achieve the above-mentioned purpose, the present invention adopts the following technical solution: a constant voltage output type wireless power and information synchronous transmission device, characterized in that: the wireless power and information synchronous transmission device includes a transmitting side and a receiving side;

[0005] The transmitting side consists of a transmitting coil L p1 , transmitting coil L p2 , Energy emission compensation topology, Information emission compensation topology, DC power supply U p, inverter circuit and information modulation circuit, among which the DC power supply U p Connected to the inverter circuit, the transmitting coil L p1 With the transmitting coil L p2 Series connection;

[0006] The energy emission compensation topology includes a compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p , compensation inductance L f1 One end is connected to the output end of the inverter circuit to compensate for the inductance L f1 The other end is connected to the compensation capacitor C f1 and compensation capacitor C p Common line terminal connection, compensation capacitor C f1 The other end and the transmitting coil L p2 The other end is connected to form a common line end and connected to the input end of the inverter circuit. The compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p satisfy: where ω p is the energy operating frequency;

[0007] The information transmission compensation topology is a series compensation topology, which includes a coupling transformer TVa self-inductance L connected in series with each other. dt and compensation capacitor C pe , coupling transformer TVa self-inductance L dt The other end is connected to the transmitting coil L p1 and the transmitting coil L p2 Common line terminal connection, compensation capacitor C pe The other end is connected to the compensation capacitor C p and the transmitting coil L p1 Collinear end connection;

[0008] The information modulation circuit includes a resonant voltage U connected in series d , resonant capacitor C dt and coupling transformer TVa, the information modulation circuit is loaded to the transmitting coil L through the coupling transformer TVa p1 superior;

[0009] The receiving side consists of a receiving coil L s1 , receiving coil L s2 , energy receiving compensation topology, information receiving compensation topology, rectification and filtering circuit and information demodulation circuit, wherein the receiving coil L s1 and receiving coil L s2 Connect in series, the rectifier filter in the rectifier filter circuit is connected to the load R L Connected to compensation capacitor C0;

[0010] The energy receiving compensation topology includes compensation capacitors C connected in series with each other. s ′ and compensation inductance L f2 , supplementary inductor L f2 The other end is connected to the input end of the rectifier filter circuit, and the compensation capacitor C s 'The other end and the receiving coil L s2 The other end is connected to form a common line end and connected to the output end of the rectifier filter circuit to compensate for the inductance L f2 With compensation capacitor C s 'satisfy: C f2 +C s =C s ';

[0011] The information receiving compensation topology is a series compensation topology, which includes a coupling transformer TVb self-inductance L connected in series with each other. dr and compensation capacitor C se , coupling transformer TVb self-inductance L dr The other end is connected to the receiving coil L s1 and receiving coil L s2 Common line terminal connection, compensation capacitor C se The other end is connected to the compensation capacitor C s ', compensation inductance L f2 and receiving coil L s1 Collinear end connection;

[0012] The information demodulation circuit includes a resonant capacitor C connected in series with each other dr and coupling transformer TVb, the voltage of the information demodulation circuit is the resonant capacitor C dr Voltage across both ends U dout The information demodulation circuit is loaded to the receiving coil L through the coupling transformer TVb. s1 superior.

[0013] Furthermore, the transmitting coil L p1 , transmitting coil L p2 , receiving coil L s1 and receiving coil L s2 All are DD coils, of which the transmitting coil L p1 With the receiving coil L s1 Parallel relative setting, transmitting coil L p2 With the receiving coil L s2 Parallel relative setting, transmitting coil L p1 and the transmitting coil L p2 Set in parallel on the same plane, the receiving coil L s1 and receiving coil L s2 Set side by side on the same plane.

[0014] A parameter design method for a constant voltage output type wireless power and information synchronous transmission device is characterized by the following specific steps:

[0015] Step S1: establishing an equivalent circuit model of a constant voltage output type wireless power and information synchronous transmission device;

[0016] Step S2: Calculate the transmitting coil current I p The relationship between the coupling mechanism parameters is as follows:

[0017]

[0018] Among them, U s is the output voltage of the inverter circuit, ω p is the energy operating frequency;

[0019] Step S3: Calculate the transmitter side compensation inductance L f1 , compensation capacitor C f1 , compensation capacitor C p The relationship between the coupling mechanism parameters is as follows:

[0020]

[0021] Step S4: Calculate the receiving side compensation inductance L f2 With compensation capacitor C s The relationship between ′ and the coupling mechanism parameters is as follows:

[0022]

[0023] Among them, C f2 、C s Calculate the capacitance for the middle respectively;

[0024] Step S5: Calculate the voltage U across the rectifier bridge input EF The relationship between the coupling mechanism parameters is as follows:

[0025]

[0026] Among them, M ps is the transmitting coil L p With the receiving coil L s mutual induction between

[0027] Step S6: Calculate the load R L Voltage across both ends U L The relationship between the coupling mechanism parameters is as follows:

[0028]

[0029] Step S7: Calculate the equivalent transmitting coil self-inductance L of the information transmitting circuit pe , equivalent receiving coil self-inductance L se and equivalent mutual inductance M e , the relational model is:

[0030]

[0031] Among them, L dt 、L dr are the self-inductances of coupling transformer TVa and coupling transformer TVb respectively; M p1p2 is the transmitting coil L p The two single D coils are the transmitting coils L p1 With the transmitting coil L p2 Mutual inductance between s1s2 The receiving coil L s The two single D coils are the receiving coils L s1 With the receiving coil L s2 k1 is the mutual inductance between the two parallel single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s1 , transmitting coil L p2 With the receiving coil L s2 The coupling coefficient between them; k2 is the two non-parallel relative single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s2 , transmitting coil L p2 With the receiving coil L s1 The coupling coefficient between

[0032] Step S8: Calculate the compensation capacitance C of the information transmission loop pe And the information receiving circuit compensation capacitor C se The relationship between the equivalent parameters of the information loop is as follows:

[0033]

[0034] Among them, ω d is the information carrier frequency.

[0035] The present invention has the following advantages and beneficial effects: The present invention solves the problem of difficulty in achieving constant voltage output of energy in the existing technology of simultaneous transmission of information and communication. The present invention designs the parameter size according to actual needs, has high practicality, and has a large degree of design freedom. Compared with the existing research on simultaneous transmission of information and communication, the receiving compensation topology of the present invention introduces parallel compensation capacitors and series compensation inductors to construct a low-pass filter circuit, which effectively suppresses high-frequency interference in the information loop and enables the simultaneous transmission of information and communication system to have constant voltage output characteristics; compared with the existing technology based on the constant voltage output system of LCC-S compensation, the present invention enables the simultaneous transmission of information and communication system to have information transmission capabilities, and can also achieve the same by compensating the inductor L f2 Reasonable design can realize flexible adjustment of output voltage value. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a circuit diagram of the constant voltage output type wireless power and information synchronous transmission device of the present invention.

[0037] Figure 2 A schematic structural diagram of a coupling mechanism provided in an embodiment of the present invention.

[0038] Figure 3 Output voltage curves under different loads provided by the embodiment of the present invention, (a) R L =20Ω; (b) R L =30Ω; (a) R L =40Ω; (b) R L =50Ω.

[0039] Figure 4 The information modulation signal and information reception voltage waveforms provided in the embodiments of the present invention, (a) modulation signal; (b) information reception voltage. DETAILED DESCRIPTION

[0040] The above contents of the present invention are further described in detail below through examples, but this should not be understood as limiting the scope of the above subject matter of the present invention to the following examples. All technologies implemented based on the above contents of the present invention fall within the scope of the present invention.

[0041] See also Figures 1-2 , the present invention provides a constant voltage output type wireless power and information synchronous transmission device, the wireless power and information synchronous transmission device includes a transmitting side and a receiving side;

[0042] The transmitting side consists of a transmitting coil L p1 , transmitting coil L p2 , Energy emission compensation topology, Information emission compensation topology, DC power supply U p , inverter circuit and information modulation circuit, among which the DC power supply U pConnected to the inverter circuit, the transmitting coil L p1 With the transmitting coil L p2 Series connection;

[0043] The energy emission compensation topology includes a compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p , compensation inductance L f1 One end is connected to the output end of the inverter circuit to compensate for the inductance L f1 The other end is connected to the compensation capacitor C f1 and compensation capacitor C p Common line terminal connection, compensation capacitor C f1 The other end and the transmitting coil L p2 The other end is connected to form a common line end and connected to the input end of the inverter circuit. The compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p satisfy: where ω p is the energy operating frequency;

[0044] The information transmission compensation topology is a series compensation topology, which includes a coupling transformer TVa self-inductance L connected in series with each other. dt and compensation capacitor C pe , coupling transformer TVa self-inductance L dt The other end is connected to the transmitting coil L p1 and the transmitting coil L p2 Common line terminal connection, compensation capacitor C pe The other end is connected to the compensation capacitor C p and the transmitting coil L p1 Collinear end connection;

[0045] The information modulation circuit includes a resonant voltage U connected in series d , resonant capacitor C dt and coupling transformer TVa, the information modulation circuit is loaded to the transmitting coil L through the coupling transformer TVa p1 superior;

[0046] The receiving side consists of a receiving coil L s1 , receiving coil L s2 , energy receiving compensation topology, information receiving compensation topology, rectification and filtering circuit and information demodulation circuit, wherein the receiving coil L s1 and receiving coil L s2 Connect in series, the rectifier filter in the rectifier filter circuit is connected to the load R L Connected to compensation capacitor C0;

[0047] The energy receiving compensation topology includes compensation capacitors C connected in series with each other. s ′ and compensation inductance L f2 , supplementary inductor L f2 The other end is connected to the input end of the rectifier filter circuit, and the compensation capacitor C s 'The other end and the receiving coil L s2 The other end is connected to form a common line end and connected to the output end of the rectifier filter circuit to compensate for the inductance L f2 With compensation capacitor C s 'satisfy: C f2 +C s =C s ';

[0048] The information receiving compensation topology is a series compensation topology, which includes a coupling transformer TVb self-inductance L connected in series with each other. dr and compensation capacitor C se , coupling transformer TVb self-inductance L dr The other end is connected to the receiving coil L s1 and receiving coil L s2 Common line terminal connection, compensation capacitor C se The other end is connected to the compensation capacitor C s ', compensation inductance L f2 and receiving coil L s1 Collinear end connection;

[0049] The information demodulation circuit includes a resonant capacitor C connected in series with each other dr and coupling transformer TVb, the voltage of the information demodulation circuit is the resonant capacitor C dr Voltage across both ends U dout The information demodulation circuit is loaded to the receiving coil L through the coupling transformer TVb. s1 superior;

[0050] The transmitting coil L p1 , transmitting coil L p2 , receiving coil L s1 and receiving coil L s2 All are DD coils, of which the transmitting coil L p1 With the receiving coil L s1 Parallel relative setting, transmitting coil L p2 With the receiving coil L s2 Parallel relative setting, transmitting coil L p1 and the transmitting coil L p2 Set in parallel on the same plane, the receiving coil L s1 and receiving coil L s2 Set side by side on the same plane.

[0051] Compared with the existing energy and information simultaneous transmission device, the constant voltage output type wireless energy and information simultaneous transmission device described in this embodiment realizes load-independent constant voltage output, and at the same time effectively suppresses the interference caused by energy inversion and rectification, thereby realizing high-quality simultaneous transmission of energy and information.

[0052] Example 1

[0053] A parameter design method for a constant voltage output wireless power and information synchronous transmission device, the specific design steps are as follows:

[0054] Step S1: establishing an equivalent circuit model of a constant voltage output type wireless power and information synchronous transmission device;

[0055] Step S2: Under the LCC compensation topology on the transmitting side, the coil current is only related to its own parameters. The transmitting coil current I p The relationship between the coupling mechanism parameters is as follows:

[0056]

[0057] Among them, U s is the output voltage of the inverter circuit, ω p is the energy operating frequency;

[0058] Step S3: According to the relationship between the compensation components in the LCC compensation topology, the transmitting compensation inductor L is obtained. f1 , compensation capacitor C f1 , compensation capacitor C p The relationship between the coupling mechanism parameters is as follows:

[0059]

[0060] Step S4: For ease of analysis, split the supplementary capacitor C s ′ is C f2 、C s , where C s Used to compensate for the coil self-inductance L s 、C f2 Used to compensate the compensation inductance L f2 , the parameters satisfy:

[0061]

[0062] Among them, C f2 、C s Calculate the capacitance for the middle respectively;

[0063] Step S5: From equations (2) and (3), the voltage U across the rectifier bridge input can be obtained: EF for:

[0064]

[0065] Among them, M ps is the transmitting coil L p With the receiving coil L s mutual induction between

[0066] Step S6: From equations (1) and (4), we can get the load R L Voltage across both ends U L for:

[0067]

[0068] Step S7: Determine the equivalent transmitting coil self-inductance L of the information transmitting circuit according to the coupling mechanism parameters of the constant voltage output type wireless power and information synchronous transmission device. pe , equivalent receiving coil self-inductance L se and equivalent mutual inductance M e , the relational model is:

[0069]

[0070] Among them, L dt 、L dr are the self-inductances of coupling transformer TVa and coupling transformer TVb respectively; M p1p2 is the transmitting coil L p The two single D coils are the transmitting coils L p1 With the transmitting coil L p2 Mutual inductance between s1s2 The receiving coil L s The two single D coils are the receiving coils L s1 With the receiving coil L s2 The mutual inductance between them; k1 is the two parallel relative single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s1 , transmitting coil L p2 With the receiving coil L s2 The coupling coefficient between them; k2 is the two non-parallel relative single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s2 , transmitting coil L p2 With the receiving coil L s1 The coupling coefficient between

[0071] Step S8: The information transmission circuit adopts a series compensation topology. The information transmission circuit compensation capacitor C can be obtained from formula (6). pe And the information receiving circuit compensation capacitor C se for:

[0072]

[0073] Among them, ω d is the information carrier frequency.

[0074] The parameter design method of the constant voltage output type wireless power and information synchronous transmission device described in this embodiment can design the parameter size according to actual needs, has high practicality, and has a large degree of design freedom. Compared with the existing constant voltage output system based on LCC-S compensation, the present invention enables the signal transmission system to have information transmission capabilities while also being able to achieve the desired effect by adjusting the compensation inductor L. f2 Reasonable design can realize flexible adjustment of output voltage value.

[0075] The parameters of the power information synchronization system determined by the above transmission device and design method are shown in Table 1. L The voltage design value is 105V, DC voltage U p The voltage is 110V and the information transmission rate is designed to be 115.2kbps.

[0076] Table 1 Parameters of power information synchronization device

[0077]

[0078] Under different loads, the load voltage waveform is as follows: Figure 3 As shown in the figure, it can be seen that when the load changes, the load voltage fluctuation value is small and stabilizes at the design value of about 105V. The designed system achieves load-independent constant voltage output. When energy is transmitted, the information modulation signal and the information receiving voltage waveform are as follows Figure 4 As shown in the figure, it can be seen that the waveform quality on the information receiving side is good. Under the above parameter design, it can achieve stable transmission of 115.2kbps information while transmitting power. In summary, the designed device successfully achieves the synchronous transmission of energy and information under constant voltage output.

[0079] The above embodiments describe the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for illustrating the principles of the present invention. Without departing from the scope of the principles of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of protection of the present invention.

Claims

1. A constant voltage output type wireless power and information synchronous transmission device, characterized by: The wireless power and information synchronous transmission device includes a transmitting side and a receiving side; The transmitting side consists of a transmitting coil L p1 , transmitting coil L p2 , Energy emission compensation topology, Information emission compensation topology, DC power supply U p , inverter circuit and information modulation circuit, among which the DC power supply U p Connected to the inverter circuit, the transmitting coil L p1 With the transmitting coil L p2 Series connection; The energy emission compensation topology includes a compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p , compensation inductance L f1 One end is connected to the output end of the inverter circuit to compensate for the inductance L f1 The other end is connected to the compensation capacitor C f1 and compensation capacitor C p Common line terminal connection, compensation capacitor C f1 The other end and the transmitting coil L p2 The other end is connected to form a common line end and connected to the input end of the inverter circuit. The compensation inductor L f1 , compensation capacitor C f1 and compensation capacitor C p satisfy: where ω p is the energy operating frequency; The information transmission compensation topology is a series compensation topology, which includes a coupling transformer TVa self-inductance L connected in series with each other. dt and compensation capacitor C pe , coupling transformer TVa self-inductance L dt The other end is connected to the transmitting coil L p1 and the transmitting coil L p2 Common line terminal connection, compensation capacitor C pe The other end is connected to the compensation capacitor C p and the transmitting coil L p1 Collinear end connection; The information modulation circuit includes a resonant voltage U connected in series d , resonant capacitor C dt and coupling transformer TVa, the information modulation circuit is loaded to the transmitting coil L through the coupling transformer TVa p1 superior; The receiving side consists of a receiving coil L s1 , receiving coil L s2 , energy receiving compensation topology, information receiving compensation topology, rectification and filtering circuit and information demodulation circuit, wherein the receiving coil L s1 and receiving coil L s2 Connect in series, the rectifier filter in the rectifier filter circuit is connected to the load R L Connected to compensation capacitor C0; The energy receiving compensation topology includes compensation capacitors C connected in series with each other. s ′ and compensation inductance L f2 , supplementary inductor L f2 The other end is connected to the input end of the rectifier filter circuit, and the compensation capacitor C s 'The other end and the receiving coil L s2 The other end is connected to form a common line end and connected to the output end of the rectifier filter circuit to compensate for the inductance L f2 With compensation capacitor C s 'satisfy: C f2 +C s =C s '; The information receiving compensation topology is a series compensation topology, which includes a coupling transformer TVb self-inductance L connected in series with each other. dr and compensation capacitor C se , coupling transformer TVb self-inductance L dr The other end is connected to the receiving coil L s1 and receiving coil L s2 Common line terminal connection, compensation capacitor C se The other end is connected to the compensation capacitor C s ', compensation inductance L f2 and receiving coil L s1 Collinear end connection; The information demodulation circuit includes a resonant capacitor C connected in series with each other dr and coupling transformer TVb, the voltage of the information demodulation circuit is the resonant capacitor C dr Voltage across both ends U dout The information demodulation circuit is loaded to the receiving coil L through the coupling transformer TVb. s1 superior.

2. The constant voltage output type wireless power and information synchronous transmission device according to claim 1, characterized in that: The transmitting coil L p1 , transmitting coil L p2 , receiving coil L s1 and receiving coil L s2 All are DD coils, among which the transmitting coil L p1 With the receiving coil L s1 Parallel relative setting, transmitting coil L p2 With the receiving coil L s2 Parallel relative setting, transmitting coil L p1 and the transmitting coil L p2 Set in parallel on the same plane, the receiving coil L s1 and receiving coil L s2 Set side by side on the same plane.

3. A parameter design method for a constant voltage output type wireless power and information synchronous transmission device according to claim 1 or 2, characterized in that The specific steps are: Step S1: establishing an equivalent circuit model of a constant voltage output type wireless power and information synchronous transmission device; Step S2: Calculate the transmitting coil current I p The relationship between the coupling mechanism parameters is as follows: Among them, U s is the output voltage of the inverter circuit, ω p is the energy operating frequency; Step S3: Calculate the transmitter side compensation inductance L f1 , compensation capacitor C f1 , compensation capacitor C p The relationship between the coupling mechanism parameters is as follows: Step S4: Calculate the receiving side compensation inductance L f2 With compensation capacitor C s The relationship between ′ and the coupling mechanism parameters is as follows: Among them, C f2 、C s Calculate the capacitance for the middle respectively; Step S5: Calculate the voltage U across the rectifier bridge input EF The relationship between the coupling mechanism parameters is as follows: Among them, M ps is the transmitting coil L p With the receiving coil L s mutual induction between Step S6: Calculate the load R L Voltage across both ends U L The relationship between the coupling mechanism parameters is as follows: Step S7: Calculate the equivalent transmitting coil self-inductance L of the information transmitting circuit pe , equivalent receiving coil self-inductance L se and equivalent mutual inductance M e , the relational model is: Among them, L dt , L dr are the self-inductances of coupling transformer TVa and coupling transformer TVb respectively; M p1p2 is the transmitting coil L p The two single D coils are the transmitting coils L p1 With the transmitting coil L p2 Mutual inductance between s1s2 The receiving coil L s The two single D coils are the receiving coils L s1 With the receiving coil L s2 k1 is the mutual inductance between the two parallel single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s1 , transmitting coil L p2 With the receiving coil L s2 The coupling coefficient between them; k2 is the two non-parallel relative single D coils on the transmitting and receiving sides, namely the transmitting coil L p1 With the receiving coil L s2 , transmitting coil L p2 With the receiving coil L s1 The coupling coefficient between Step S8: Calculate the compensation capacitance C of the information transmission loop pe And the information receiving circuit compensation capacitor C se The relationship between the equivalent parameters of the information loop is as follows: Among them, ω d is the information carrier frequency.

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