Insulator deicing system based on wireless power transmission technology

Abstract

The utility model provides an insulator deicing system based on a wireless power transmission technology, and relates to the technical field of wireless power transmission and disaster prevention and reduction of power transmission lines. The system is constructed by adopting a multi-stage WPT transmission technology based on a domino coil; comprising a primary side energy transmitting module, a first secondary side energy receiving and ice melting module, a second secondary side energy receiving and ice melting module, a third secondary side energy receiving and ice melting module and a fourth secondary side energy receiving and ice melting module which work under the same resonant frequency and are sequentially arranged in the energy transmission direction. Wherein the primary side energy transmitting module comprises a primary side power supply circuit, a transmitting coil circuit and a maximum power point tracking closed-loop control circuit. And all the secondary side energy receiving and ice melting modules comprise receiving coil circuits and switching circuits connected in series with the output ends of the receiving coil circuits. The system has the advantages of being high in energy transmission efficiency, high in energy utilization rate, high in system stability and capable of adapting to complex application environments.

Description

TECHNICAL FIELD

[0001] The utility model relates to wireless power transmission and power transmission line disaster prevention and mitigation technical field especially relates to an insulator deicing system based on wireless power transmission technology. BACKGROUND

[0002] With the frequent occurrence of extreme cold weather, how to realize the real-time monitoring and ablation of insulator icing, effectively avoid the fault of power transmission and distribution line caused by ice flashover, and ensure the safe and stable operation of power grid have become the current research direction, among which wireless power transmission technology as a kind of power transmission mode with high voltage isolation characteristics and long distance power supply capacity has attracted more and more attention.

[0003] The insulator anti-icing technology mainly develops around three aspects: structure design optimization, surface anti-icing function construction and active heating technology. Among them, in terms of structure, the optimization of umbrella skirt and the layout of insulator string (such as V type, inverted T type, etc.) can effectively reduce the bridging of ice ridge and relieve the distortion of space electric field. In addition, the use of super large umbrella skirt can enhance the shielding effect and slow down the speed of ice ridge bridging. In terms of surface anti-icing, the research focuses on the design of micro / nano structure such as super-hydrophobic coating and slippery surface (such as SLIPS), which can reduce the adhesion of ice by using low surface energy and micro / nano structure, improve the ice shedding capacity, and has the advantages of low energy consumption and no pollution. In terms of active heating, the electric heating coating and the photo-thermal coating technology can effectively melt ice through heating.

[0004] However, the above-mentioned prior art still has the following limitations in practical application: in terms of structure design optimization, the design parameters (such as umbrella skirt size and spacing) have great influence on anti-icing effect and electric field distribution, and the optimization is difficult. The use of super large umbrella skirt can easily cause the aggravation of space electric field distortion, which needs to be accurately controlled. In terms of surface anti-icing, the preparation process of lubricating layer and hydrophobic surface is complex, the cost is high, and it is difficult to be popularized on a large scale, and its durability, anti-ultraviolet and mechanical wear resistance still need to be improved. In terms of active heating, the mechanical durability of electric heating and photo-thermal coating is insufficient, which is easy to damage or fail, reduces the service life, and has the problems of high energy consumption and possible influence on the insulation performance of insulator. Electric heating coating needs high power input, which may cause leakage current and affect the safety of line, and photo-thermal coating is limited by environmental light intensity, which has limited effect in rainy and cloudy conditions.

[0005] The Chinese patent with the application number 202222879655.3, "An ice melting device for insulator", provides a portable ice melting device for insulator. The device includes a handheld rod and an ice melting component connected by an adjusting component; the ice melting component contains a support rod, an electric control box, a cavity connecting plate and two cavity arc-shaped plates; a small air blower is arranged inside the electric control box, and an electric heating wire is arranged inside the connecting plate; when the device is started, the air blower generates airflow, which is heated by the electric heating wire, and then the hot air enters the arc-shaped plate through the connecting plate, and finally blows to the surface of the insulator from the air outlet pipe on the inner wall of the arc-shaped plate; the hot air melts or loosens the ice layer, thereby realizing convenient and efficient ice melting operation for insulator. However, the device has technical defects in practicality and safety, that is, the device relies on small electric heating wires and air blowers to generate hot air, which has limited power, and for thick ice on the surface of high-voltage insulators, there are problems of low ice melting efficiency and high energy consumption, and the continuous operation capacity is insufficient due to the limitation of battery capacity. More importantly, the scheme requires the operator to hold a metal rod close to the high-voltage line for operation, which has a very high risk of electric shock. At the same time, concentrated hot air may damage the silicone rubber material of composite insulators, and the convenience claimed by the device is difficult to achieve in complex field environments.

[0006] The Chinese patent with the application number 201910209894.8, "A porcelain insulator with heat-absorbing ice melting device", provides a new insulator structure with self-ice melting function. The insulator includes an insulator column, a composite umbrella skirt and an arc rod; the innovation lies in that the composite umbrella skirt is embedded with a replacement rod, and the outer side of the insulator is installed with an inclined strut through a sleeve rod and a connecting shaft, and the surface of the inclined strut is bonded with a convex lens; when sunlight shines, the convex lens focuses light to generate heat, which is conducted to the replacement rod inside the composite umbrella skirt through the inclined strut, and the replacement rod uniformly disperses the heat to the entire umbrella skirt surface, so that the ice layer is melted by heat; the structure realizes self-absorbing heat melting ice by using solar energy, and at the same time enhances the mechanical strength of the umbrella skirt, and has the effects of reinforcement and stress dispersion. However, the defects of this scheme are more fundamental, mainly reflected in the unreliability of energy source and the reliability of the structure itself. The scheme completely relies on sunlight, and completely fails in snowy and cloudy weather or at night, and even in sunny days, the weak focused heat is far from enough to melt the actual thickness of ice layer. In addition, the external lens and support rod not only increase the weight and wind load of the insulator, but also are easy to age and fall off in harsh natural environment, which introduces new mechanical failures and safety hazards, and the passive working mode cannot meet the active and precise ice prevention requirements. Practical new type

[0007] The utility model provides a kind of insulator deicing system based on wireless power transmission technology, to solve the problem of current high-voltage transmission line insulator anti-icing technology low efficiency, slow response, insufficient automation, compared with prior art, with the advantages of high energy transmission efficiency, high energy utilization, strong system stability, can adapt to complex application environment.

[0008] To solve the above technical problems, the technical solution adopted by the utility model includes the following processes:

[0009] A kind of insulator deicing system based on wireless power transmission technology, the system is constructed using multi-stage WPT transmission technology based on domino coil, including working at the same resonant frequency: primary energy emission module, first secondary side energy receiving ice melting module, second secondary side energy receiving ice melting module, third secondary side energy receiving ice melting module, fourth secondary side energy receiving ice melting module;

[0010] The primary energy emission module, first secondary side energy receiving ice melting module, second secondary side energy receiving ice melting module, third secondary side energy receiving ice melting module and fourth secondary side energy receiving ice melting module are arranged in turn along the energy transmission direction, and constitute a multi-stage coupled magnetic circuit.

[0011] Further, the primary energy emission module includes: primary power supply circuit, transmitting coil circuit and maximum power point tracking closed-loop control circuit;

[0012] Wherein the primary power supply circuit and transmitting coil circuit are connected in series to form a power transmission main circuit;The maximum power point tracking closed-loop control circuit is coupled with the primary power supply circuit, and the working point of the power transmission main circuit is adjusted dynamically to realize maximum power tracking.

[0013] Further, the primary power supply circuit is composed of current transformer, DC-DC converter and DC-AC converter;

[0014] Wherein the current transformer is installed on the transmission line to be deiced;The output end of the current transformer is connected with the input end of the DC-DC converter, and the output end of the DC-DC converter is connected with the input end of the DC-AC converter;The output end of the DC-AC converter is connected with the input end of the transmitting coil circuit.

[0015] Further, the transmitting coil circuit comprises: a double-layer magnetic coupling transmitting coil, a first distributed compensation capacitor, and a second distributed compensation capacitor; the double-layer magnetic coupling transmitting coil and the first distributed compensation capacitor are connected in series to form a first series branch, and the double-layer magnetic coupling transmitting coil and the second distributed compensation capacitor are connected in series to form a second series branch; the first series branch and the second series branch are connected in series, and the circuit after the series connection is used as an input end of the transmitting coil circuit.

[0016] The double-layer magnetic coupling transmitting coil is a double-layer nested solenoid type coil.

[0017] Further, the maximum power point tracking closed-loop control circuit comprises: a current sensor, a filter circuit, an operational amplifier circuit, and a micro control unit (MCU).

[0018] The input end of the current sensor is connected to the transmitting coil circuit to collect a current signal of the transmitting coil, the output end of the current sensor is connected to the filter circuit, the operational amplifier circuit, and the micro control unit (MCU) in sequence, and the output end of the micro control unit (MCU) is connected to the control end of the direct-current alternating-current converter.

[0019] Further, the first, second, third, and fourth auxiliary-side energy receiving ice melting modules each comprise a receiving coil circuit and a switching circuit connected in series with the output end of the receiving coil circuit.

[0020] Further, the receiving coil circuit comprises: a double-layer magnetic coupling receiving coil; the double-layer magnetic coupling receiving coil is connected in series with two distributed compensation capacitors respectively to form two independent series branches; and the two independent series branches are connected in series.

[0021] The double-layer magnetic coupling receiving coil is a double-layer stacked planar circular coil.

[0022] Further, the switching circuit comprises: an ice melting on-off control circuit and a heating load connected in parallel.

[0023] The ice melting on-off control circuit comprises: a PTC thermistor, one end of the PTC thermistor is connected to the positive pole of a direct-current power supply, the other end of the PTC thermistor is connected in series with a voltage dividing resistor and then grounded; the voltage dividing point of the PTC thermistor and the voltage dividing resistor is connected to the inverting input end of an operational amplifier; the positive pole of the direct-current power supply is also connected in series with two voltage dividing resistors and then grounded, and the voltage dividing point of the two voltage dividing resistors is connected to the non-inverting input end of the operational amplifier. and The voltage division point of the voltage divider is connected to the non-inverting input terminal of the operational amplifier; the output terminal of the operational amplifier is connected to the input pin of the DSP; and the output pin of the DSP is connected to the input terminal of the MOSFET driving circuit, and the output terminal of the MOSFET driving circuit is connected to the gate of the MOSFET to drive the turn-on and turn-off of the MOSFET.

[0024] The technical scheme has the beneficial effects that:

[0025] The utility model discloses a multistage coupling principle based on domino coil, and builds a reconfigurable domino WPT system suitable for 35kV four-piece insulator, and the advancement of the technical scheme is from the depth fusion and synergistic effect of four core technologies, and the high efficiency, intelligence, stability and reliability of the system are ensured together. Specific analysis is as follows:

[0026] (1) using domino coil to carry out multistage WPT transmission, improve the robustness of system: the utility model discloses the introduction between the transmitting coil and the receiving coil Multiple relay coils with the same resonant frequency, build a continuous coupling magnetic flux transmission link, realize the step-by-step efficient transmission of energy in space. Compared with the traditional two-stage coupling mode, it has more advantages in transmission efficiency, and has higher tolerance to local mismatch of the system, and has good robustness. The frequency of each coil in the system is consistent, which can simplify impedance matching and control strategy, and reduce the complexity of engineering implementation.

[0027] (2) using double-layer coil winding mode and distributed compensation method to improve transmission efficiency: the former enhances the magnetic coupling path to improve the energy transmission efficiency, and the latter optimizes the circuit tuning mechanism to maintain the stability of the resonance condition. The utility model combines the two, which significantly improves the comprehensive performance of the WPT system in the application of medium and short distance efficient power supply, and is especially suitable for engineering scenes with high requirements for transmission efficiency, compact structure and electrical stability.

[0028] (3) using MOSFET to realize the automatic reconfiguration of WPT system parameters, so as to complete the redistribution of power: the utility model discloses that the ice melting on-off control circuit is installed at the receiving coil or the load, and the local temperature change is monitored in real time. MOSFET is used as a modal switching switch, which is closed when the temperature reaches the set trigger temperature, and the load is short-circuited, so as to realize the power consumption of the load, promote the receiving coil to switch from the energy output mode to the energy relay mode, and then dynamically redistribute the power to other loads. When the temperature decreases to the reset temperature, the MOSFET is disconnected, and the load restores the power receiving. The mechanism realizes the autonomous reconfiguration of the working mode through temperature feedback, avoids local overheating, ensures the reasonable distribution of system power and the demand of each level load, and does not need additional communication line. When the optimal working frequency deviates due to the change of system parameters, the mechanism can still maintain efficient and stable energy transmission, effectively solving the engineering problem of online ice prevention of high-voltage insulator.

[0029] (4) Use the primary side current detection method without communication to track the maximum power point to improve the output power: the utility model discloses through sampling and analyzing the current signal of the transmitting side, judges whether the system is near the maximum power operating point. Based on this feedback, the control algorithm dynamically adjusts the operating frequency or modulation parameter of the transmitting end to accurately track the maximum power point of the load, realizing stable and efficient output power. Since all monitoring and control are completed in the transmitting end, the system hardware architecture is significantly simplified, and the cost and maintenance difficulty are reduced.

[0030] In summary, the utility model designs a wireless power transmission system with multi-load and multi-power level output capability for the ice melting needs of insulators in different scenarios. The system has a simple and compact structure, stable output power, high transmission efficiency, and full-automatic operation capability. Through accurate power distribution and control strategy, it ensures that single-stage load can obtain stable power output exceeding 80W. The system has a flexible modular structure, which can dynamically adjust the transmission path and power distribution according to the arrangement of insulators and environmental conditions, adapt to different insulator quantities and load differences, thereby significantly improving the ice melting efficiency, increasing the overall energy utilization rate, realizing efficient coverage and accurate power supply for multiple insulator groups, and enhancing the system's adaptability to complex scenarios, providing an innovative wireless power supply solution for intelligent maintenance of high-voltage transmission lines.

[0031] The system has passed experimental verification and can continuously and stably operate in a 35kV power equipment environment. It has made a key breakthrough in energy transmission efficiency, with a minimum transmission efficiency exceeding 80% and a maximum transmission efficiency exceeding 90%. This effect is achieved by using a domino coil structure, multi-stage coupling design, and optimized compensation and control strategy, effectively reducing energy loss, improving coupling coefficient and resonance stability. Efficient energy transmission ensures the stability and continuity of power supply, significantly improving energy utilization rate. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 It is a working schematic diagram of the insulator deicing system based on wireless power transmission technology in the embodiment for 35kV insulators.

[0033] Figure 2 It is a circuit model diagram of the insulator deicing system based on wireless power transmission technology in the embodiment.

[0034] Figure 3 It is a schematic diagram of the maximum power point tracking closed-loop control circuit in the embodiment.

[0035] Figure 4 It is a circuit diagram of the maximum power point tracking closed-loop control circuit in the embodiment.

[0036] Figure 5 Fig. 1 is a schematic diagram of the ice melting on-off control circuit in the embodiment;

[0037] Figure 6 Fig. 2 is a working schematic diagram of the arbitrary secondary side energy receiving ice melting module in the embodiment;

[0038] Figure 7 Fig. 3 is a diagram of four working modes of the insulator deicing system in the embodiment;

[0039] Figure 8 Fig. 4 is a control flowchart of the working of the insulator deicing system in the embodiment;

[0040] Figure 9 Fig. 5 is an ANSYS Maxwell magnetic field simulation result of the insulator deicing system in the embodiment;

[0041] Figure 10 Fig. 6 is an ANSYS Maxwell electric field simulation result of the insulator deicing system in the embodiment. DETAILED DESCRIPTION

[0042] The utility model will be made further detailed description in combination with the drawings and specific embodiments.

[0043] As Figure 1 and Figure 2 shown, the embodiment provides an insulator deicing system based on wireless power transmission technology, which is constructed by using multi-stage WPT transmission technology based on domino coils, and includes primary side energy transmitting modules, first secondary side energy receiving ice melting modules, second secondary side energy receiving ice melting modules, third secondary side energy receiving ice melting modules and fourth secondary side energy receiving ice melting modules working at the same resonant frequency.

[0044] The primary side energy transmitting modules, the first secondary side energy receiving ice melting modules, the second secondary side energy receiving ice melting modules, the third secondary side energy receiving ice melting modules and the fourth secondary side energy receiving ice melting modules are arranged in sequence along the energy transmission direction and constitute a multi-stage coupled magnetic circuit.

[0045] In the embodiment, as Figure 2 shown, by constructing a continuous coupled magnetic flux transmission link, efficient energy transmission is realized step by step in space. The structure design realizes higher integration while keeping the overall coil size compact, and is especially suitable for embedded wireless power supply systems with limited space and layout.

[0046] The primary side energy transmitting module includes a primary side power supply circuit, a transmitting coil circuit and a maximum power point tracking closed-loop control circuit.

[0047] The primary side power supply circuit is connected in series with the transmitting coil circuit to form a power transmission main loop; and the maximum power point tracking closed loop control circuit is coupled with the primary side power supply circuit to realize maximum power tracking by dynamically adjusting the working point of the power transmission main loop.

[0048] The primary side power supply circuit is composed of a current transformer, a DC-DC converter and a DC-AC converter.

[0049] The current transformer is installed on the power transmission line to be deiced; the output end of the current transformer is connected with the input end of the DC-DC converter, the output end of the DC-DC converter is connected with the input end of the DC-AC converter; and the output end of the DC-AC converter is connected with the input end of the transmitting coil circuit.

[0050] In this embodiment, the current transformer is installed on the power transmission line to be deiced to capture the magnetic field energy around the power transmission line and convert it into electric energy; the current flows from the output end of the current transformer into the input end of the DC-DC converter through a wire, and after the current is stabilized by the DC-DC converter, the current flows from the output end of the DC-DC converter into the input end of the DC-AC converter through a wire, and after the current is inverted by the DC-AC converter, the current flows from the output end of the DC-AC converter into the transmitting coil circuit through a wire.

[0051] The transmitting coil circuit comprises a double-layer magnetic coupling transmitting coil, a first distributed compensation capacitor and a second distributed compensation capacitor; the double-layer magnetic coupling transmitting coil and the first distributed compensation capacitor are connected in series to form a first series branch, and the double-layer magnetic coupling transmitting coil and the second distributed compensation capacitor are connected in series to form a second series branch; the first series branch and the second series branch are connected in series, and the circuit after the series connection serves as the input end of the transmitting coil circuit; and the double-layer magnetic coupling transmitting coil adopts a double-layer nested solenoid type coil.

[0052] In this embodiment, the double-layer magnetic coupling transmitting coil structure adopted by the transmitting coil circuit can effectively improve the quality factor of the coil and improve the system efficiency and transmission capacity of the insulator deicing system based on the wireless power transmission technology. The transmitting coil circuit is composed of the double-layer magnetic coupling transmitting coil connected in series with the two distributed compensation capacitors, and the distributed series compensation network is formed by connecting the two in series through a matching wire. Compared with the centralized parallel compensation, the distributed parallel compensation and the centralized series compensation, the transmission efficiency of the insulator deicing system based on the wireless power transmission technology can be greatly improved.

[0053] At the circuit topology level, the embodiment introduces a distributed capacitance compensation technology to replace the traditional centralized compensation scheme. The distributed compensation strategy can more finely control the resonance condition by uniformly arranging multiple small-capacity compensation capacitors in the transmitting end and the receiving end loop, thereby effectively alleviating the system detuning problem caused by frequency deviation and coupling strength change. This method not only improves the resonance stability of the WPT system under multiple working conditions, but also reduces the voltage stress and heat accumulation effect of local devices, and improves the thermal management capability and long-term operation reliability of the system.

[0054] The maximum power point tracking closed-loop control circuit comprises a current sensor, a filter circuit, an operational amplifier circuit and a micro control unit MCU.

[0055] The input end of the current sensor is connected to the transmitting coil circuit to collect the current signal of the transmitting coil, and the output end of the current sensor is connected to the filter circuit, the operational amplifier circuit and the micro control unit MCU in turn, and the output end of the micro control unit MCU is connected to the control end of the direct-current alternating-current converter.

[0056] In the embodiment, as shown in Figure 3 and Figure 4 The output end of the current sensor is input to the MCU through differential amplification and filtering.

[0057] The first, second, third and fourth auxiliary side energy receiving ice melting modules each comprise a receiving coil circuit and a switching circuit connected in series with the output end of the receiving coil circuit.

[0058] The receiving coil circuit comprises a double-layer magnetic coupling receiving coil, and the double-layer magnetic coupling receiving coil is connected in series with two distributed compensation capacitors to form two independent series branches, and the two independent series branches are connected in series.

[0059] The double-layer magnetic coupling receiving coil is a double-layer stacked planar circular coil.

[0060] In the embodiment, the transmitting coil is a double-layer nested solenoid coil, and the corresponding four-stage receiving coil is designed as a double-layer stacked planar circular coil to facilitate integration in an insulator disc. In terms of magnetic coupling path, a double-layer solenoid structure is used instead of a traditional single-layer coil design. This structure increases the turn density in a unit area by stacking the upper and lower layers, thereby significantly enhancing the magnetic flux strength and coupling coefficient, and to some extent, suppressing the magnetic leakage effect, which helps to improve the stability of the system under lateral or angular deviation conditions.

[0061] The switching circuit comprises an ice melting on-off control circuit and a heating load connected in parallel.

[0062] like Figure 5 As shown, the ice-melting on / off control circuit includes: a PTC thermistor, one end of which is connected to the positive terminal of a DC power supply, and the other end of which is connected to a voltage divider resistor. The circuit is connected in series and then grounded; the voltage divider point of the PTC thermistor and the voltage divider resistors is connected to the inverting input of the operational amplifier; two voltage divider resistors are also connected in series at the positive terminal of the DC power supply. and After grounding, and and The voltage divider point is connected to the non-inverting input of the operational amplifier; the output of the operational amplifier is connected to the input pin of the DSP; the output pin of the DSP is connected to the input of the MOSFET driver circuit, and the output of the MOSFET driver circuit is connected to the gate of the MOSFET to drive the MOSFET to turn on and off.

[0063] Specifically, the first secondary energy receiving and de-icing module consists of a first receiving coil circuit and a first switching circuit connected in series. The first receiving coil circuit is composed of a double-layer magnetically coupled receiving coil connected in series with two distributed compensation capacitors, and then connected in series via matching wires. That is, it adopts a distributed series compensation network composed of a double-layer magnetically coupled transmitting coil connected in series with two distributed compensation capacitors. The first switching circuit consists of a first de-icing on / off control circuit connected in parallel with a first heating load.

[0064] The second secondary energy receiving and de-icing module consists of a second receiving coil circuit and a second switching circuit connected in series. The second receiving coil circuit comprises a double-layer magnetically coupled receiving coil connected in series with two distributed compensation capacitors, and then connected in series via matching wires. The second switching circuit consists of a second de-icing on / off control circuit connected in parallel with a second heating load.

[0065] The third secondary energy receiving and de-icing module consists of a third receiving coil circuit and a third switching circuit connected in series. The third receiving coil circuit is composed of a double-layer magnetically coupled receiving coil connected in series with two distributed compensation capacitors, and then connected in series via matching wires. The third switching circuit consists of a third de-icing on / off control circuit connected in parallel with a third heating load.

[0066] The fourth secondary energy receiving and de-icing module consists of a fourth receiving coil circuit and a fourth switching circuit connected in series. The fourth receiving coil circuit is composed of a double-layer magnetically coupled receiving coil connected in series with two distributed compensation capacitors, and then connected in series via matching wires. The fourth switching circuit consists of a fourth de-icing on / off control circuit connected in parallel with a fourth heating load.

[0067] The energy conversion process in the process of ice removal of the insulator is as follows: the current transformer on the power transmission line converts the magnetic field generated around the cable into electric energy, and the DC-DC voltage stabilizing module and the DC-AC inverter module convert the direct current into alternating current; the alternating magnetic field generated on the transmitting coil propagates to the receiving coil, and the receiving coil generates an alternating electric field under the alternating magnetic field; the heating load absorbs the electric energy generated by the receiving coil and converts it into heat energy, so that the temperature of the insulator disc is increased to prevent water vapor from condensing on the surface of the insulator disc.

[0068] As shown in Figure 6 and Figure 7 , when the temperature of the insulator disc is lower than the trigger temperature, the first MOSFET is kept open, and the power is applied to the first heating load ; when the temperature of the insulator disc is higher than the trigger temperature, the first MOSFET is closed, and is short-circuited, so that the energy is no longer consumed, the first receiving coil circuit is switched from the energy receiving mode to the energy relay mode, and the power is transmitted to the second heating load , so that the power is redistributed, and when the temperature of the insulator disc is lower than the reset temperature, the first MOSFET is opened, and the first receiving coil circuit reenters the energy receiving state.

[0069] When the temperature of the insulator disc is lower than the trigger temperature, the second MOSFET is kept open, and the power is applied to the second heating load ; when the temperature of the insulator disc is higher than the trigger temperature, the second MOSFET is closed, and is short-circuited, so that the energy is no longer consumed, the second coil circuit is switched from the energy receiving mode to the energy relay mode, and the power is transmitted to the third heating load , so that the power is redistributed, and when the temperature of the insulator disc is lower than the reset temperature, the second MOSFET is opened, and the second receiving coil circuit reenters the energy receiving state.

[0070] When the temperature of the insulator disc is lower than the trigger temperature, the third MOSFET is kept open, and the power is applied to the third heating load ; when the temperature of the insulator disc is higher than the trigger temperature, the third MOSFET is closed, and is short-circuited, so that the energy is no longer consumed, the third coil circuit is switched from the energy receiving mode to the energy relay mode, and the power is transmitted to the fourth heating load , so that the power is redistributed, and when the temperature of the insulator disc is lower than the reset temperature, the third MOSFET is opened, and the third receiving coil circuit reenters the energy receiving state.

[0071] The fourth ice-melting on-off control circuit, when the temperature of the insulator disc is lower than the trigger temperature, the fourth MOSFET keeps open, and the power is applied to the first heating load In the above, when the temperature of the insulator disc is higher than the trigger temperature, the fourth MOSFET is closed, short-circuited and no longer consumes energy, when the temperature of the insulator disc is lower than the reset temperature, the fourth MOSFET is open, and the fourth receiving coil circuit re-enters the energy receiving state.

[0072] The use process of the utility model will be described below in combination with the drawings.

[0073] In use, as Figure 1 shown, the utility model is erected on a disc-shaped suspension insulator with an umbrella skirt diameter of 255 mm and an umbrella distance of 150 mm. Figure 2 As shown, The DC voltage converted by the current transformer and the DC-DC converter in the primary side power supply circuit is the DC voltage converted by the current transformer and the DC-DC converter in the primary side power supply circuit. The positive pole of the DC power supply is connected to the drain of the switch tube and at the same time, forming an upper bridge arm. The negative pole of the DC power supply is connected to the source of the switch tube and at the same time, forming a lower bridge arm. The source of the switch tube is connected to the drain of the switch tube at the same time, forming a lower bridge arm. The source of the switch tube is connected to the drain of the switch tube at the same time, forming a lower bridge arm. Each switch tube ( ) is connected in parallel with an anti-parallel diode for providing a freewheeling circuit. A controllable amplitude and variable direction AC output can be generated between points A and B. The inverter output nodes A and B are connected to the primary side resonant circuit, which is mainly composed of a distributed equivalent compensation capacitor of the transmitting coil circuit and a double-sided transmitting coil decoupling equivalent inductance

[0074] in series, forming a series resonant network. Among them:

[0075] ;

[0076] Among them, and are the self-inductances of the inner and outer transmitting coils; is the mutual inductance of the inner and outer transmitting coils; and are two distributed series compensation capacitors, respectively.

[0077] The primary coil The four receiving coils are coupled with the transmitting coil by spatial magnetic field in the form of electromagnetic induction. 、 、 、 Each receiving coil circuit is symmetrically composed of a first distributed equivalent compensation capacitor of the receiving coil circuit and a second decoupling equivalent inductor of the double-layer receiving coil .

[0078] ;

[0079] ;

[0080] wherein and are self-inductances of the upper and lower receiving coils; is mutual inductance between the upper and lower receiving coils; and are corresponding distributed series compensation capacitors. Further, the capacitor is connected in series with the inductor , and each forms a series resonant circuit, and the end of each circuit is connected with a first mode switching switch and a second heating load .

[0081] The circuit state equation of the insulator deicing system based on wireless power transmission is:

[0082] ;

[0083] wherein is an alternating voltage applied to the transmitting coil circuit; is self-impedance of the transmitting coil circuit, and ; is self-impedance of the first receiving coil circuit, and ; and are mutual inductances between the coils; ; ; ; is current of the transmitting coil circuit; is current of the first receiving coil circuit; represents on-off state of the mode switching switch, and is specifically defined as follows:

[0084] ;

[0085] in Indicates the first The switching state of a MOSFET. For example... Figure 5 As shown, this embodiment installs an ice-melting on / off control circuit at the receiving coil or load, and proposes an automatic parameter reconstruction and power redistribution scheme based on MOSFET to achieve dynamic adaptive control of the system. The MOSFET acts as a mode-switching switch, and its turn-on and turn-off process is as follows: when the temperature of the insulator disc... Below the trigger temperature At this time, the MOSFET remains off, and power is applied to the heated load. Above, the receiving coil operates in power output mode. As the temperature rises, Greater than When the MOSFET is closed, When short-circuited, the coil ceases to consume energy and switches from energy receiving mode to energy relay mode. Power is then transferred to the downstream load, completing the power redistribution. The coil continues operation until the temperature drops to the reset temperature. hour, Disconnect again to re-enter energy receiving mode. These measures allow for the redistribution of output power, ensuring effective anti-icing operation for each insulator panel.

[0086] like Figure 7 As shown, this utility model system provides four working modes. , , , Based on the switching states of each MOSFET, each receiving coil can be categorized into power output states. and energy relay state Before the insulators are de-iced, the temperature of each insulator disc is lower than the MOSFET trigger temperature. , All in In this state, all coils are in energy-receiving mode, and the four loads simultaneously receive power to provide heat to the insulator discs. Because the power of the preceding load is greater than that of the following load, the preceding insulator disc will reach the preset temperature before the following insulator disc, causing the preceding MOSFET to close first, while the following MOSFET remains open. Power is then redistributed to the remaining loads. Therefore, the MOSFETs close sequentially from front to back. The entire de-icing process of the proposed insulator de-icing system based on wireless power transfer technology can be summarized.

[0087] The maximum power point tracking (MPPT) closed-loop control circuit is used to achieve closed-loop control of the output power of the secondary energy receiving de-icing module, enabling the system to automatically track and maintain the maximum power point of the heating load's output energy. Specifically, such as...Figure 3 and Figure 4 The current sensor detection circuit in the primary side circuit detects the primary side current in different working modes The output signal is input to the MCU, and the MCU detects that When the value is less than a certain threshold (which can be obtained by simulation and is related to the working mode), the working frequency of the system is switched. In The maximum power point of the system is different in different working modes. By analyzing the simulation values of the primary side current in different working modes, the current threshold for switching between modes can be determined. When the system working mode changes and the frequency does not switch in time, the primary side current will have a significant low value. Setting these low values as the switching points, i.e. the current threshold points for switching the working frequency, can ensure that the system can quickly switch to the corresponding maximum power point working frequency in different working modes, ensuring that the system always outputs maximum power and effectively preventing the problem of insufficient heating speed of the insulator due to low power.

[0088] When the insulator disc is heated to a preset temperature, the detection circuit detects the corresponding action current and switches the corresponding working frequency accordingly. This allows the system to always work in a maximum power output state, achieving maximum power point tracking and effectively preventing insufficient heating speed caused by low power, ensuring the effectiveness of the insulator anti-icing scheme. As Figure 8 shown, working at a corresponding working frequency When the temperature of the first stage insulator disc reaches the preset temperature, the MOSFET is closed, at which time the system enters , but the working frequency is still , the output power is not at the maximum power point, and the primary side current is significantly reduced to . When the MCU detects this value, the working frequency is switched to , so that works at the maximum power point. Similarly, as the temperature of each stage of the insulator disc increases, when the frequency is not switched, there will be another two current values and . Therefore, the currents , are set as the switching points of to and to respectively.

[0089] ANSYS Maxwell magnetic field simulation of an insulator deicing system based on wireless power transmission is performed for this embodiment, as Figure 9As shown, the magnetic field strength on the transmission path is obviously stronger, the magnetic field strength vector is constrained on the expected transmission path, and it is ensured that the multi-stage coil can effectively obtain electric energy.

[0090] The ANSYS Maxwell electric field simulation of the insulator deicing system based on wireless power transmission proposed in the embodiment is carried out, as shown in the following figure: Figure 10 As shown, under the high-voltage environment of 35kV voltage level, the maximum electric field strength of the domino magnetic coupling structure in the embodiment is less than , which is much lower than the breakdown field strength of air . Therefore, the good transmission capacity and insulation performance of the proposed system are effectively verified, and the insulation performance of the 35kV insulator will not be affected.

[0091] Finally, it should be pointed out that the scheme in the embodiment is not intended to limit the protection scope of the utility model, and any equivalent implementation or change without departing from the utility model is included in the scope defined by the utility model.

Claims

1. An ice-melting system for insulators based on wireless power transfer technology, characterized in that, The system is constructed by using multi-stage WPT transmission technology based on domino coil, including the following modules working at the same resonant frequency: a primary energy transmitting module, a first secondary energy receiving ice melting module, a second secondary energy receiving ice melting module, a third secondary energy receiving ice melting module, and a fourth secondary energy receiving ice melting module. The primary energy transmitting module, the first secondary energy receiving ice melting module, the second secondary energy receiving ice melting module, the third secondary energy receiving ice melting module, and the fourth secondary energy receiving ice melting module are arranged in sequence along the energy transmission direction, and form a multi-stage coupling magnetic circuit.

2. The ice-melting system based on wireless power transmission technology for insulators according to claim 1, characterized in that, The primary energy transmitting module comprises a primary power supply circuit, a transmitting coil circuit, and a maximum power point tracking closed-loop control circuit. The primary power supply circuit and the transmitting coil circuit are connected in series to form a power transmission main loop; the maximum power point tracking closed-loop control circuit is coupled with the primary power supply circuit, and the working point of the power transmission main loop is dynamically adjusted to realize maximum power tracking.

3. The ice-melting system based on wireless power transmission technology for insulators according to claim 2, characterized in that, The primary power supply circuit is composed of a current transformer, a DC-DC converter, and a DC-AC converter. The current transformer is installed on the power transmission line to be deiced; the output end of the current transformer is connected with the input end of the DC-DC converter, the output end of the DC-DC converter is connected with the input end of the DC-AC converter; and the output end of the DC-AC converter is connected with the input end of the transmitting coil circuit.

4. The ice-melting system based on wireless power transmission technology for insulators according to claim 2, characterized in that, The transmitting coil circuit comprises a double-layer magnetic coupling transmitting coil, a first distributed compensation capacitor, and a second distributed compensation capacitor; the double-layer magnetic coupling transmitting coil and the first distributed compensation capacitor are connected in series to form a first series branch, the double-layer magnetic coupling transmitting coil and the second distributed compensation capacitor are connected in series to form a second series branch; the first series branch and the second series branch are connected in series, and the two ends of the series-connected circuit serve as the input end of the transmitting coil circuit. The double-layer magnetic coupling transmitting coil adopts a double-layer nested solenoid type coil.

5. The ice-melting system based on wireless power transmission technology for insulators according to claim 2, characterized in that, The maximum power point tracking closed-loop control circuit comprises a current sensor, a filter circuit, an operational amplifier circuit, and a micro control unit (MCU). The input end of the current sensor is connected to the transmitting coil circuit to collect the current signal of the transmitting coil; the output end of the current sensor is connected in sequence with the filter circuit, the operational amplifier circuit, and the micro control unit (MCU); and the output end of the micro control unit (MCU) is connected to the control end of the DC-AC converter.

6. The ice-melting system based on wireless power transmission technology for insulators according to claim 1, characterized in that, The first secondary energy receiving ice melting module, the second secondary energy receiving ice melting module, the third secondary energy receiving ice melting module, and the fourth secondary energy receiving ice melting module each comprise a receiving coil circuit and a switching circuit connected in series with the output end of the receiving coil circuit.

7. The ice-melting system based on wireless power transmission technology for insulators according to claim 6, characterized in that, The receiving coil circuit comprises a double-layer magnetic coupling receiving coil; the double-layer magnetic coupling receiving coil is connected in series with two distributed compensation capacitors to form two independent series branches; and the two independent series branches are connected in series. The double-layer magnetic coupling receiving coil is a double-layer stacked planar circular coil.

8. The ice-melting system based on wireless power transmission technology for insulators according to claim 6, characterized in that, The switching circuit comprises an ice melting on-off control circuit and a heating load connected in parallel. The ice melting on-off control circuit comprises a PTC thermistor, one end of the PTC thermistor is connected to a positive pole of a direct current power supply, the other end of the PTC thermistor is connected to a voltage dividing resistor is grounded in series; a voltage dividing point of the PTC thermistor and the voltage dividing resistor is connected to an inverting input terminal of an operational amplifier; the positive pole of the direct current power supply is also connected to two voltage dividing resistors in series and is grounded in series, and and a voltage dividing point of the two voltage dividing resistors is connected to a non-inverting input terminal of the operational amplifier; an output terminal of the operational amplifier is connected to an input pin of a DSP; an output pin of the DSP is connected to an input terminal of a MOSFET driving circuit, and an output terminal of the MOSFET driving circuit is connected to a gate of a MOSFET to drive the MOSFET to turn on and turn off.

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