Method and system for building microwave energy collecting device of electronic transformer

Abstract

The invention discloses a method and a system for building a microwave energy collection device of an electronic transformer, and the method comprises the steps: collecting and analyzing a first signal transmitted by a first object, and selecting an antenna; and performing simulation analysis according to the first characteristic parameter of the antenna, and further screening a proper antenna. And constructing a first network and a circuit of the first object, performing simulation, and collecting first signal energy. According to the microwave energy collection device for the electronic mutual inductor provided by the invention, the influence of an antenna and a matching circuit on the performance of a radio frequency energy collection system is fully considered; the antenna, the impedance matching circuit and the energy management circuit are comprehensively designed from the aspect of energy utilization efficiency, so that the electronic transformer can realize stable power supply by collecting microwave energy in a working environment.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic mutual inductors, and in particular to a method and system for constructing a microwave energy collection device of an electronic mutual inductor. Background Art

[0002] Most traditional current measurement technologies use direct contact, so the insulation layer must be stripped off first, and then the power supply must be disconnected before measurement can be performed. In contrast, non-contact measurement technology can more conveniently utilize information about the surrounding environment, thereby more accurately reflecting the electrical parameters of the cable, and will not damage the insulation layer. The operation is also more convenient, and the measurement task can be completed more quickly and accurately. Electronic transformers came into being.

[0003] At present, electronic transformers are mainly powered by the power grid. Due to the particularity of the power grid, most of the flowing electricity is alternating current. Therefore, the alternating electromagnetic field can be converted into electrical energy output through a transformer through a Rogowski coil, and then DC voltage stabilization is achieved through appropriate rectification, filtering, voltage stabilization and other processing steps for use by power detection equipment. However, the current in the power grid changes with the change of power load, and the power consumption habits are different at different times. This indicates that the power obtained by CT power supply is unstable, which poses a great challenge to the instrumentation. In addition, any fluctuations in the power grid will affect the stability of the power supply for CT power supply, thereby introducing new uncertainty factors into the detection equipment and making the measurement accuracy of the electronic transformer unstable.

[0004] Applying RF energy harvesting technology to the power grid to power the current sensing system in the power grid can effectively solve the energy constraint problem of sensor nodes in high voltage and high current situations. However, since the technology is still in the research and development stage and is not mature yet, there are still many challenges in the actual implementation of microwave energy harvesting systems, mainly concentrated in the following aspects:

[0005] 1) RF energy harvesting hardware technology is immature. During the hardware system development process, RF energy harvesting technology based on electromagnetic radiation belongs to far-field wireless charging. Although its charging distance is long, its charging efficiency is low. The reactive energy loss and leakage of components will further reduce the charging efficiency. In order to achieve ultra-long-distance stable wireless charging, the energy harvesting device must be able to detect weak electromagnetic wave signals and collect and convert weak RF energy. Considering the above factors, higher requirements are put forward for the hardware design of rechargeable sensor nodes. According to actual needs, this article needs to develop an ultra-low energy consumption and high charging efficiency RF energy harvesting device based on electromagnetic radiation.

[0006] 2) How to manage the collected energy. When the antenna receives RF energy and obtains DC power through the voltage doubler rectifier circuit, it is an urgent problem to effectively manage this power and continue to provide stable and reliable functions for the subsequent circuits. Generally, the RF energy after rectification and voltage doubler is very weak and cannot directly power the subsequent detection circuit. Therefore, it is necessary to design an efficient and stable power management circuit to enable the subsequent current detection system to work stably and continuously for a long time. Summary of the invention

[0007] In view of the above-mentioned problems, the present invention is proposed.

[0008] Therefore, the technical problem solved by the present invention is that the existing technology is still in the research and development stage and is not yet mature, and there are still many challenges in the actual implementation of the microwave energy harvesting system.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for building a microwave energy collection device of an electronic mutual inductor, comprising: collecting and analyzing a first signal emitted by a first object, and selecting an antenna.

[0010] A simulation analysis is performed based on the first characteristic parameter of the antenna to further screen a suitable antenna.

[0011] A first network and circuit of the first object are constructed, and simulation is performed to collect first signal energy.

[0012] As a preferred solution of the method for building a microwave energy collection device for an electronic mutual inductor described in the present invention, the method comprises collecting and analyzing the first signal emitted by the first object and selecting the antenna, collecting and analyzing the first signal source as the energy object to be collected, and selecting a single antenna with multiple different structural parameters of the corresponding frequency according to the first signal parameters.

[0013] As a preferred solution of the method for constructing a microwave energy collection device of an electronic mutual inductor described in the present invention, the first characteristic parameters of the antenna include the structural parameters and electromagnetic field of the antenna.

[0014] As a preferred solution of the method for building a microwave energy collection device for an electronic mutual inductor described in the present invention, the further screening of suitable antennas includes selecting antennas whose simulation analysis results of the first characteristic parameters meet preset requirements, and continuously collecting the transmitted signals of the first object during operation.

[0015] As a preferred solution of the method for constructing a microwave energy collection device of an electronic mutual inductor described in the present invention, wherein: the first object includes but is not limited to an electronic mutual inductor.

[0016] The first signal is a microwave signal source emitted by an electronic mutual inductor.

[0017] The structural parameters of the antenna include frequency bandwidth, center frequency and impedance analysis results.

[0018] The first network and circuit include but are not limited to an impedance matching network and a rectification circuit.

[0019] As a preferred solution of the method for building a microwave energy collection device of an electronic mutual inductor described in the present invention, the first network and circuit of the first object are constructed and simulated, including using lumped elements to form an impedance matching network, setting initial parameters, and simulating the impedance matching network using a Smith chart tool to obtain a reflection coefficient curve of a double-branch impedance matching circuit, adjusting the parameters of the impedance matching network according to the reflection coefficient curve, and repeating the simulation until the simulation results of the impedance matching network meet preset requirements.

[0020] A unipolar voltage-doubling rectifier circuit of the selected frequency is constructed using a Schottky diode. A related circuit model is established in the simulation software and simulation is performed to obtain the impedance of the rectifier circuit.

[0021] As a preferred solution of the method for constructing a microwave energy collection device for an electronic mutual inductor described in the present invention, the first signal energy collection includes integrating and simulating the impedance matching network and the rectifier circuit in combination with the impedance of the rectifier circuit obtained by simulation. The first signal energy collection device is constructed by combining the antenna, the integrated impedance matching network and the rectifier circuit to collect the first signal emitted during the operation of the first object.

[0022] A microwave energy collection device construction system for an electronic mutual inductor, characterized in that it includes:

[0023] The acquisition module acquires and analyzes the first signal transmitted by the first object and selects an antenna.

[0024] The screening module performs simulation analysis according to the first characteristic parameter of the antenna to further screen a suitable antenna.

[0025] A simulation module constructs a first network and a circuit of the first object, performs simulation, and collects first signal energy.

[0026] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0027] A computer-readable storage medium stores a computer program, which implements the steps of the method described above when executed by a processor.

[0028] Beneficial effects of the present invention: The microwave energy collection device for an electronic mutual inductor of the present invention fully considers the influence of the antenna and the matching circuit on the performance of the radio frequency energy collection system, and comprehensively designs the antenna, the impedance matching circuit, and the energy management circuit from the perspective of energy efficiency, so that the electronic mutual inductor can achieve stable power supply by collecting microwave energy in the working environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. Among them:

[0030] Figure 1 An overall flow chart of a method and system for constructing a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention;

[0031] Figure 2 The S11 simulation results of a method and system for building a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention;

[0032] Figure 3 The 433 antenna impedance analysis results of a method and system for building a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention;

[0033] Figure 4 The electromagnetic field simulation results of the 433MHz antenna of a method and system for building a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention;

[0034] Figure 5 A method for constructing a microwave energy collection device of an electronic mutual inductor and a double-branch microstrip line matching circuit of the system provided in the first embodiment of the present invention;

[0035] Figure 6 A method for constructing a microwave energy collection device of an electronic mutual inductor and Smith chart impedance matching of the system provided in the first embodiment of the present invention;

[0036] Figure 7 A method for building a microwave energy collection device of an electronic mutual inductor and a characteristic curve of an impedance matching circuit reflection coefficient of the system provided in the first embodiment of the present invention;

[0037] Figure 8 A method for constructing a microwave energy collection device of an electronic mutual inductor and a single-stage voltage doubling rectifier circuit of the system provided in the first embodiment of the present invention;

[0038] Fig. 9 A schematic diagram of a voltage doubling rectifier circuit of a method for building a microwave energy collection device of an electronic mutual inductor and a system provided in the first embodiment of the present invention;

[0039] Fig.10 A structure diagram of an impedance matching voltage doubling rectifier circuit of a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention and a system thereof;

[0040] Fig.11 A method for constructing a microwave energy collection device of an electronic mutual inductor and an input impedance of a rectifier voltage doubler impedance matching circuit of the system provided in the first embodiment of the present invention;

[0041] Fig.12 A method for constructing a microwave energy collection device of an electronic mutual inductor and an impedance matching voltage doubling rectifier circuit layout of the system provided in the first embodiment of the present invention;

[0042] Fig.13 A circuit diagram of a method and system for constructing a microwave energy collection device of an electronic mutual inductor provided in the first embodiment of the present invention;

[0043] Fig.14 A method for constructing a microwave energy collection device of an electronic mutual inductor and an energy collection circuit of the system provided in the first embodiment of the present invention;

[0044] Fig.15 A physical diagram of a boost module circuit of a method for building a microwave energy collection device of an electronic mutual inductor and a system provided in the first embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary persons in the art without creative work should fall within the scope of protection of the present invention.

[0046] Example 1, reference Figure 1 to Figure 15 , as an embodiment of the present invention, provides a method for constructing a microwave energy collection device of an electronic mutual inductor, comprising:

[0047] S1: Collect and analyze a first signal transmitted by a first object, and select an antenna.

[0048] In the present invention, the first object is an electronic transformer, and the first signal is a microwave signal emitted by the electronic transformer. The microwave signal source emitted by the electronic transformer is collected and analyzed, and is used as the collected energy object, and a plurality of single antennas with different structural parameters of corresponding frequencies are selected according to the parameters of the microwave signal source emitted by the electronic transformer.

[0049] The first object includes, but is not limited to, an electronic mutual inductor, and may also be a remote wireless sensor node, a wireless module of an industrial control system, and a small communication base station.

[0050] In an optional embodiment of the present invention, the first object is a remote wireless sensor node. For remote wireless sensor nodes, especially environmental monitoring stations installed in remote areas, wireless communication technology is usually used to send low-power microwave signals, such as 2.4GHz or 915MHz and other common frequency bands. To ensure effective microwave energy collection, it is first necessary to collect the microwave signal emitted by the sensor node and analyze its characteristics, especially the parameters such as the frequency, power density, propagation characteristics and polarization mode of the signal. In view of the characteristics of the remote wireless sensor node, the following aspects need to be considered when selecting the antenna:

[0051] Frequency selection: Based on the frequency bandwidth of the signal source, select the antenna type that can match the frequency band of the sensor node to ensure maximum energy capture efficiency.

[0052] Multi-directional coverage: Since sensor nodes may be affected by factors such as wind direction and terrain in the natural environment, the directionality of their transmitted signal strength is weak. Therefore, the selected antenna should be omnidirectional or have wide coverage to better capture multi-directional signals.

[0053] Optimization of structural parameters: Using simulation software and multi-band antenna structure design, the center frequencies are set at 2.4GHz and 915MHz respectively to capture signals in different frequency bands at the same time.

[0054] In this case, the antenna structure that matches the node transmission frequency and power characteristics is selected through simulation to ensure stable energy harvesting under the condition of fluctuations in the transmission signal of the remote wireless sensor node.

[0055] In an optional embodiment of the present invention, the first object is a wireless module of an industrial control system, which is usually equipped with a wireless module for real-time monitoring and feedback of control signals. These wireless modules frequently transmit microwave signals, and the frequency bands are mainly concentrated in the industrial, scientific and medical (ISM) bands, such as 5.8GHz or 2.4GHz. The signals of wireless modules are usually more concentrated, but due to the many obstacles in the industrial site, the signal propagation will be interfered, and there may be a strong multipath effect. For the signal acquisition of industrial control wireless modules, the considerations when selecting antennas include:

[0056] Multipath anti-interference capability: The antenna design must be able to effectively resist interference. You can give priority to directional Yagi antennas or parabolic reflector antennas to achieve stronger signal capture capabilities with higher gain.

[0057] Adapt to frequency offset: Considering the interference sources in industrial scenarios, the module signal frequency band may be slightly offset. The antenna design needs to take into account the center frequency offset range to ensure signal stability.

[0058] Signal gain optimization: Optimize antenna gain through simulation to achieve better signal reception efficiency in frequency bands such as 5.8 GHz or 2.4 GHz.

[0059] The antenna design simulation in this scenario takes into account the signal anti-interference and adaptability, so that the antenna can still effectively collect microwave signals when the frequency band is offset, achieving more reliable energy collection in industrial environments.

[0060] In an optional embodiment of the present invention, the first object is a small communication base station, which is widely used in 5G and Internet of Things (IoT) environments, and the signal frequency it transmits is relatively high, such as the millimeter wave frequency band above 28GHz. Due to the high frequency band, the strength of its transmitted signal is easily affected by distance and obstacles. For the collection of microwave signals of small base stations, the antenna selection needs to pay attention to the following aspects:

[0061] Frequency bandwidth requirements: Select an antenna that is adapted to the millimeter wave band and ensure that the antenna frequency range covers the high-frequency signals of small base stations.

[0062] High gain and focusing: Millimeter wave signals attenuate rapidly during propagation, so the antenna needs to have high gain to ensure that microwave energy can still be effectively collected under high-frequency conditions.

[0063] Miniaturized design: Due to the limited size of small base stations, compact waveguide slot antennas or microstrip antennas and other efficient structures are selected to enable the antenna to collect high-frequency signals without taking up too much space.

[0064] By simulating the reflection coefficient, bandwidth and gain characteristics of high-frequency band antennas, the optimal millimeter-wave antenna structure is selected for energy collection of small base station signals.

[0065] It should be stated that antennas are an important part of RF energy harvesting systems. Antenna types can be classified based on frequency band, antenna gain, radiation pattern, polarization, physical size, or application area, etc. For example, some antennas can be used in specific frequency bands, such as VHF and UHF. Dipole antennas, loop antennas, array antennas, horn antennas, aperture antennas, microstrip antennas, and log-periodic antennas are some common antenna types. Antenna gain is a measure of the conversion from an RF signal to an electrical signal in a specified direction. In terms of antenna gain, high-gain antennas are preferred because they can improve the conversion efficiency and directly increase the collected energy. Antenna radiation can be isotropic or directional. When the location of the RF signal source (transmitter) is known, directional antennas can be used to increase the collected energy. Otherwise, isotropic antennas can be used. Antenna polarization defines the direction of the electric field at the observation point. If both the transmitting and receiving antennas have the same polarization, the conversion efficiency increases. Horizontal, vertical, circular, and elliptical polarization are antenna polarization types. Compared with multi-band antennas, single-band antennas are simple to design and manufacture, but have limited energy harvesting efficiency. In addition, if a multi-band energy harvesting circuit is designed, the output DC voltage level of the RF energy harvester can be improved, but the antenna replication degree is increased and the volume becomes larger. Broadband antennas are suitable for receiving power from a wide frequency band, but their antenna gain decreases as the center frequency increases. In addition, providing impedance matching within a wide frequency band is a very challenging task.

[0066] Multiple antennas are suitable for harvesting more power. More power may improve the RF-DC conversion efficiency, but the use of multiple antennas will lead to an increase in circuit size and increase costs. The microwave signal collected in this project is a type of microwave signal source provided by the project itself. The power of the transmitted signal source is below 33dBm, which meets the national standard requirements, and it is a single-frequency microwave signal source. Therefore, a single antenna solution is selected in this project. In order to improve the collection efficiency of microwave energy and reduce the microwave propagation loss in the environment, this project uses a 433MHz microwave source as the energy object to be collected. At the same time, in order to speed up the development progress of the project, this project uses currently commercial antennas as microwave energy collection antennas. The selected antenna gain is 4dBi. The use of high-gain antennas can further increase the amount of collected energy and polarization matching. According to the size of the antenna, simulation analysis is performed, and the S11 parameters obtained are as follows Figure 2 As shown in the figure, it can be found that the frequency bandwidth of the antenna used is narrow, and the center frequency is around 433MHz. The impedance analysis results obtained by testing the antenna are as follows Figure 3 As shown. Figure 3 It can be found that the impedance of the antenna used is close to 50Ω, which meets the project design requirements. At the same time, the electromagnetic field of the antenna is simulated according to the structural dimensions of the antenna, and the results are as follows Figure 4 As shown. Figure 4It can be found that the electromagnetic field distribution of the selected antenna in the circumferential direction is relatively uniform, and there will be no directionality problem.

[0067] S2: Perform simulation analysis based on the first characteristic parameter of the antenna to further select a suitable antenna.

[0068] In the present invention, the first characteristic parameter of the antenna includes the structural parameters and electromagnetic field of the antenna. A simulation analysis is performed based on the structural parameters of each antenna to obtain its frequency bandwidth, center frequency and impedance analysis results, and the electromagnetic field of the antenna is simulated. An antenna whose frequency bandwidth, center frequency, impedance analysis results and circumferential electromagnetic field distribution uniformity results all meet the preset requirements is selected, and the microwave signal energy emitted by the electronic mutual inductor is continuously collected during the working process.

[0069] S3: construct a first network and circuit of the first object, perform simulation, and collect first signal energy.

[0070] An impedance matching network is constructed using lumped elements. The impedance matching network has a π-type topology structure. The initial parameters are set according to empirical data. The impedance matching network is simulated using the Smith chart tool in the ADS simulation software to obtain the reflection coefficient curve of the double-branch impedance matching circuit. The parameters of the impedance matching network are adjusted according to the reflection coefficient curve. The simulation is repeated until the simulation results of the impedance matching network meet the preset requirements.

[0071] A unipolar voltage doubler rectifier circuit of the selected frequency is constructed using a Schottky diode. The relevant circuit model is established in the ADS simulation software and the impedance of the rectifier circuit is obtained by simulation.

[0072] Combined with the impedance of the rectifier circuit obtained by simulation, the impedance matching network and the rectifier circuit are integrated and simulated. The integrated antenna, the integrated impedance matching network and the rectifier circuit are used to build a microwave energy harvesting device to collect the microwave signal energy emitted during the working process of the electronic mutual inductor.

[0073] It should be noted that in order to achieve maximum power transfer between the antenna and the rectifier circuit, the impedance of the antenna should be equal to the complex conjugate of the impedance of the rectifier circuit. Otherwise, power loss will occur, and efficiency will decrease. Reactors generally use diodes and other circuit elements. Due to the nonlinear characteristics of the diode, the impedance of the rectifier changes with the operating frequency, input power level and load impedance. Therefore, the impedance matching circuit of nonlinear elements becomes a very challenging topic. Double branch microstrip line matching circuit such as Figure 5 ,

[0074] Because the frequency band of the embodiment of the present invention is 433Mhz, the wavelength is relatively long and it is not suitable to use microstrip line. Meanwhile, 433M is within 1Ghz, and discrete components with inductors and capacitors can be used to achieve matching. Therefore, the impedance matching circuit adopts a π-type topology structure for matching. Figure 6 .

[0075] pass Figure 6 It can be found that the RF signal first enters the circuit through the input port, which is equivalent to a port Term1 with an impedance value of 50Ω in the figure, and then passes through the matching part. The Term2 port is the impedance value of the original rectifier and voltage doubler circuit. After setting it like this, it simulates the matching effect of this matching structure on the current impedance value of the circuit to the ideal 50Ω.

[0076] The present invention has a frequency of 433MHz, which is a lower frequency than 900MHz, 2.4GHz, 5.8GHz, etc. If distributed components, i.e., transmission lines, are used for transmission, the wavelength will be longer due to the low frequency, which will cause the length of the transmission line to be too long, thereby further increasing the size of the overall circuit. Therefore, lumped components can be used to form an impedance matching network. The parameters of the lumped components are obtained from the Smith chart tool in the ADS simulation software.

[0077] After setting the relevant parameters, first complete the simulation of this structure to check whether it achieves the desired matching function. The obtained data is shown in Figure 7 , refers to the reflection coefficient curve of the double-branch impedance matching circuit. As can be seen from the figure, its center frequency is near 433MHz, which is very close to 433MHz and can be approximately regarded as 433M, and it is very accurate in the middle position. In addition, it can be found from the figure that the reflection coefficient of the center frequency has the lowest value of -22.991dB, and the reflection coefficient at 433Mhz is -19.626dB, which also shows that the impedance matching of the designed circuit is very good.

[0078] In the structure of the rectifier circuit, the present invention selects a single-stage voltage doubling full-wave rectifier structure because of its high conversion efficiency, output is also twice that of a half-wave rectifier structure, and has lower loss. The circuit form selects a double-tube series-parallel rectifier structure, two capacitors are used to store energy, and smoothly output DC voltage. The schematic diagram of the single-stage voltage doubling rectifier circuit is shown in Figure 8 , V RF_IN is the antenna RF input, V DC_OUT It is the rectified DC output.

[0079] The rectifier circuit requires that the selected rectifier diode has a low forward turn-on threshold voltage and sufficient reverse breakdown threshold voltage, small series resistance and junction capacitance, and especially good high-frequency characteristics in this RF band. After comparing the electrical parameters of different types of diodes, the SMS7630-79 Schottky diode was finally selected, especially its junction capacitance CT is 0.3pF, and the series inductance is only 0.7nH, which ensures good high-frequency characteristics. The forward conduction voltage of the tube is in the range of 60 to 120mV, and the reverse breakdown voltage is 2V, which ensures a low power loss and sufficient voltage output. Due to the nonlinearity of the diode, the rectifier circuit also has different input impedances when working at different frequencies, which is a large loss for energy transmission, so impedance matching is required. A circuit model was established in ADS and simulated to obtain the impedance of the 433Mhz frequency rectifier circuit. See the circuit diagram. Fig. 9 .

[0080] After completing the analysis and design of the impedance matching and rectifier voltage doubler circuits, the next thing to consider is how to combine the two parts of the circuit together. Because after adding the rectifier voltage doubler circuit, the rectifier voltage doubler circuit itself has impedance characteristics, and the previous matching will also be out of tune, so it is necessary to analyze and design it as a whole. The designed rectifier circuit consists of an impedance matching network with a π-type topology structure, a single-stage voltage doubler rectifier structure consisting of two 7630 Schottky diodes, and a load. Two Schottky diodes are used to achieve waveform rectification, and two 100pF energy storage capacitors are used to store DC energy so that the DC voltage can be output stably. The operating frequency, input power, and load size will affect the input impedance of the rectifier structure, and comprehensive considerations are required to achieve the best reflection loss and the most efficient conversion rate. The overall circuit structure is as follows Fig.10 The overall DC output simulation results of the impedance matching voltage doubler rectifier circuit are as follows: Fig.11 shown.

[0081] from Fig.12 It can be seen that the input impedance value of the circuit at the resonant frequency point, i.e., 433Mhz, is approximately 58.836+j*7.183, and the real part is close to 50Ω. The overall impedance matching is good and has a good reflection coefficient. Because the value of the load resistance at the output end affects the output, that is, as the load value increases, the voltage divided in the circuit increases, and the output voltage increases, but the conversion efficiency is related to the power, and is a nonlinear relationship with the load. As the load increases, there will be a maximum value. By observing the circuit output under different load conditions, the final structure of the circuit is determined. Finally, the output voltage and conversion efficiency are comprehensively weighed, and the final selected input power is 0dBm (about 1mW), and the optimal load is determined to be 3kΩ. At this time, the output voltage can reach about 1.3V or more. At this time, according to the efficiency calculation formula:

[0082]

[0083] By substituting in relevant parameters, it can be concluded that the overall conversion efficiency is above 56%.

[0084] Due to the difference between the discrete device simulation process and the actual device, the overall matching effect is not optimal. This project also carried out the design of a matching network based on microstrip lines. The circuit layout simulated in ADS is as follows Fig.13 The overall size of the board is 29×21cm, and the thickness is 1.6mm. The dark reddish-brown part in the figure is the transmission microstrip line. Its routing width is calculated by ADS software according to different impedance values. The double-branch impedance matching structure can be seen in the front, and the rectifier part microstrip line structure is in the back. After the board is made, the capacitors and diodes should be welded accordingly.

[0085] The overall size of the impedance matching rectifier circuit board is 29×13mm, and the thickness of the RF4 board is 1.6mm. The impedance matching rectifier circuit is made into a physical object for actual testing, such as Fig.14 and Fig.15 The following are the measurement pictures and physical pictures of the circuit. By measuring the energy collection efficiency of the circuit, its efficiency is close to 70%, which shows that its matching effect has improved. However, this circuit is based on the circuit manufacturing process to realize microstrip line production, and the boards in the same batch vary greatly. For this reason, the impedance matching rectification and voltage doubling solution based on discrete devices or microstrip lines can be selected according to actual needs to combine the advantages of both.

[0086] Furthermore, the method for constructing a microwave energy collection device includes the following steps:

[0087] Build an energy management circuit, which includes a battery, a power management chip and a boost module. According to actual needs, the undervoltage threshold UV, the battery good threshold VBAT_OK and the overvoltage threshold VBAT_OV of the power management chip are set by external programmable resistors.

[0088] When the front end of the boost module has a cold start voltage input greater than 330mV and the cold start power is greater than 15μW, the power management chip starts working and the battery starts charging until the voltage of VSTOR is charged above 1.8V, and the cold start phase ends.

[0089] Furthermore, the power management chip uses the BQ25504 chip.

[0090] The BOOST boost module switch is turned on, the boost module starts the hot start mode, the charging speed is accelerated, and when VBAT reaches the VBAT_OK_HYST threshold, VBAT_OK outputs a high level signal.

[0091] When the VBAT pin reaches the overvoltage threshold VBAT_OV, charging stops.

[0092] In the present invention, the battery low voltage protection is set to 2.23 V. The battery over voltage protection is set to 3.15 V. VBAT_OK_PROG is set to 2.44 V. VBAT_OK_HYST is set to 2.84 V.

[0093] The above embodiments also include a microwave energy collection device construction system for an electronic mutual inductor, specifically:

[0094] The acquisition module acquires and analyzes the first signal transmitted by the first object and selects an antenna.

[0095] The screening module performs simulation analysis based on the first characteristic parameter of the antenna to further screen the appropriate antenna.

[0096] The simulation module constructs a first network and circuit of the first object, performs simulation, and collects first signal energy.

[0097] The computer device may be a server. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected via a system bus, and the communication interface is connected to the system bus via the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data cluster data of the power monitoring system. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a method for building a microwave energy collection device for an electronic mutual inductor is implemented.

[0098] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment method can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0099] Embodiment 2 is an embodiment of the present invention, which provides a method and system for building a microwave energy collection device of an electronic mutual inductor. In order to verify the beneficial effects of the present invention, scientific demonstration is carried out through simulation experiments.

[0100] Test preparation and detailed process

[0101] In order to verify the effectiveness of a method for building a microwave energy collection device for an electronic mutual inductor, the experiment takes the electronic mutual inductor as the research object, and compares the performance of the present invention with the traditional method in terms of microwave energy collection efficiency through simulation and actual measurement. The existing technology mainly relies on fixed frequency antennas and single matching circuits, resulting in low energy collection efficiency. In the experiment, the present invention improves the microwave energy collection efficiency of the system by selecting a suitable antenna, constructing an impedance matching network and a rectifier circuit.

[0102] Subjects:

[0103] Existing technology: Using conventional microwave antennas and matching circuits, it fails to effectively adapt to frequency fluctuations and has low energy collection efficiency.

[0104] The present invention adopts a single antenna with a frequency of 433 MHz, selects a suitable impedance matching network through simulation, and combines a single-stage voltage doubler rectifier circuit to optimize the energy collection effect.

[0105] Experimental steps:

[0106] Collect microwave signals and select antennas: The microwave signals emitted by the electronic mutual inductor are collected and their frequency and power parameters are analyzed. In the prior art, fixed frequency antennas are difficult to adapt to signal fluctuations, and the energy collection efficiency is limited. The present invention selects antennas based on a frequency of 433MHz and optimizes their structural parameters in simulation analysis to adapt to different transmission environments.

[0107] Constructing impedance matching network: Lumped elements are used to design impedance matching network, and the initial parameters are simulated and optimized using Smith chart. The present invention adopts double-branch matching circuit design, and repeatedly adjusts simulation parameters to achieve the best impedance matching with the rectifier circuit. The matching circuit in the existing method fails to be dynamically optimized for different environments, and the efficiency is low.

[0108] Build a rectifier circuit and test: A rectifier circuit model is built in the simulation software, and a single-stage voltage doubler rectifier structure is constructed using a Schottky diode. The rectified DC output voltage is used to evaluate the energy collection effect. The experiment records and compares the microwave energy collection efficiency of the two methods through physical construction and testing. The experimental results are shown in Table 1.

[0109] Table 1 Experimental results

[0110]

[0111] The table data shows that the present invention has significant advantages in microwave energy collection, and the specific analysis is as follows:

[0112] The existing technology has a low energy collection efficiency of only 40% due to the fixed frequency antenna design. The present invention improves the efficiency to 70% by optimizing the antenna structure and impedance matching network, which is an increase of 75%.

[0113] The conventional method uses a fixed antenna with a gain of 2dBi, which is difficult to meet the requirements of efficient energy collection. The present invention uses a high-gain antenna, and the gain is increased to 4dBi, which is 100% higher and increases the stability of energy collection.

[0114] The reflection coefficient of the matching circuit in the existing method is -10dB, while after optimization in the present invention, the reflection coefficient is -20dB, and the optimization range is 50%, which further improves the antenna matching performance.

[0115] The traditional method requires about 30 minutes to manually adjust the parameters. The present invention shortens the construction time to 10 minutes through simulation optimization design, reducing the working time by 66.67%.

[0116] The DC output voltage of the prior art rectifier circuit is 0.8V, which is a relatively low output. The present invention optimizes the matching network and the rectifier circuit, and the DC output voltage reaches 1.3V, which is increased by 62.5%, thereby improving the output capacity of the energy collection system.

[0117] In the existing system, the load resistance is fixed at 1 kΩ, and the output voltage is relatively low. The present invention uses a load resistance of 3 kΩ, achieves a higher DC voltage output, and optimizes the circuit load matching effect.

[0118] The maintenance cost of the traditional method is about 5,000 yuan per year. The present invention reduces the cost to 3,000 yuan by optimizing the circuit and antenna design, saving 40%.

[0119] In summary, the experimental results show that the method for building a microwave energy harvesting device with an electronic mutual inductor is significantly superior to the existing technology in terms of energy harvesting efficiency, antenna gain, matching performance and system maintenance cost.

[0120] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for constructing a microwave energy collection device for an electronic mutual inductor, characterized in that: include: Collecting and analyzing a first signal transmitted by a first object, and selecting an antenna; Performing simulation analysis according to the first characteristic parameter of the antenna to further select a suitable antenna; A first network and circuit of the first object are constructed, and simulation is performed to collect first signal energy.

2. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 1, characterized in that: The collecting and analyzing the first signal emitted by the first object and selecting the antenna include collecting and analyzing the first signal source as the energy object to be collected, and selecting a single antenna with multiple different structural parameters at the corresponding frequency according to the first signal parameters.

3. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 2, characterized in that: The first characteristic parameters of the antenna include structural parameters and electromagnetic fields of the antenna.

4. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 3, characterized in that: The further screening of suitable antennas includes selecting antennas whose simulation analysis results of the first characteristic parameters meet preset requirements, and continuously collecting signals emitted by the first object during operation.

5. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 4, characterized in that: The first object is not limited to an electronic mutual inductor; The first signal is a microwave signal emitted by an electronic transformer; The structural parameters of the antenna include frequency bandwidth, center frequency and impedance analysis results; The first network and circuit include but are not limited to an impedance matching network and a rectification circuit.

6. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 5, characterized in that: The constructing the first network and circuit of the first object and performing simulation includes: using lumped elements to form an impedance matching network, setting initial parameters, simulating the impedance matching network using a Smith chart tool, obtaining a reflection coefficient curve of a double-branch impedance matching circuit, adjusting parameters of the impedance matching network according to the reflection coefficient curve, and repeating the simulation until the simulation result of the impedance matching network meets preset requirements; A unipolar voltage-doubling rectifier circuit of the selected frequency is constructed using a Schottky diode. A related circuit model is established in the simulation software and simulation is performed to obtain the impedance of the rectifier circuit.

7. The method for constructing a microwave energy collection device of an electronic mutual inductor according to claim 6, characterized in that: The collecting of the first signal energy includes integrating and simulating the impedance matching network and the rectifier circuit in combination with the impedance of the rectifier circuit obtained by simulation; The first signal energy collection device is constructed by combining the antenna, the integrated impedance matching network and the rectifier circuit to collect the first signal emitted during the operation of the first object.

8. A system for constructing a microwave energy collection device of an electronic mutual inductor using the method according to any one of claims 1 to 7, characterized in that: A collection module, collecting and analyzing a first signal transmitted by a first object, and selecting an antenna; A screening module, performing simulation analysis according to the first characteristic parameter of the antenna to further screen a suitable antenna; A simulation module constructs a first network and circuit of the first object, performs simulation, and collects first signal energy.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.

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