An output switching type continuous arch bridge type CPT system and a switching method

Abstract

The present application relates to unmanned aerial vehicle wireless power transmission technology, in particular to an output switching type continuous arch bridge type CPT system and a switching method, the system comprises an unmanned aerial vehicle and a platform; it also comprises a wireless power transmitting module, a wireless power receiving module and a coupling mechanism; the wireless power transmitting module comprises a direct current input power supply, a high frequency inverter circuit and a transmitting side compensation circuit; the wireless power receiving module comprises a receiving side compensation circuit, a rectifier circuit, a filter capacitor, a filter inductor and a load resistor; the coupling mechanism comprises a wireless power transmitting electrode plate, a wireless power receiving electrode plate and a coupling circuit. The system not only has a very small cross coupling capacitance of the coupling mechanism, but also can greatly reduce the coupling capacitance change of the transmitting electrode plate and the receiving electrode plate when the unmanned aerial vehicle has a landing deviation, and can realize constant voltage and constant current output switching under the premise of avoiding communication between the transmitting electrode plate side and the receiving electrode plate side.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of unmanned aerial vehicle wireless power transmission, and particularly relates to an output switching type continuous arch bridge type CPT system and a switching method. BACKGROUND

[0002] Unmanned aerial vehicles can replace manual implementation of tasks such as inspection, surveying and mapping, and environmental monitoring, and have been used in many fields. However, due to the weight limitation of the equipment carried by the unmanned aerial vehicle, the unmanned aerial vehicle cannot carry a large-capacity battery, resulting in a short endurance time. Therefore, the unmanned aerial vehicle must solve the problem of power supply when operating over a long distance and a large range.

[0003] The capacitive power transfer (CPT) technology has a broad application prospect in the field of unmanned aerial vehicles. The technology solves the problems of the traditional contact charging system, such as difficult accurate docking of the contact, aging of the contact, and limited use environment, and can more safely and conveniently supplement the power of the unmanned aerial vehicle.

[0004] The CPT system mainly realizes wireless connection transmission of power between the transmitting end and the receiving end by means of two pairs of plates. The transmitting plate and the receiving plate are respectively installed below the charging platform and the unmanned aerial vehicle. The energy emitting side (transmitting plate) generates a cross-link with the energy receiving side (receiving plate) through a high-frequency changing electric field to realize power transmission.

[0005] The coupling structure of the transmitting plate and the receiving plate is an energy transmission structure of a high-frequency and high-voltage electric field. The coupling condition determines the anti-deviation performance of the system and affects the transmission performance of the system. In order to improve the transmission performance of the system, the topology (compensation structure) is essential for the CPT system. The functions that can be realized by the topology include: filtering high-order harmonics generated by the inverter; providing a higher excitation voltage for the coupling mechanism; reducing the volt-ampere capacity of the system; improving the system efficiency; and realizing constant current / constant voltage output independent of the load. SUMMARY

[0006] In view of the problems in the background art, the application provides an output switching type continuous arch bridge type CPT system. The system not only has a very small cross-coupling capacitance of the coupling mechanism, but also can greatly reduce the change of the coupling capacitance of the transmitting plate and the receiving plate when the unmanned aerial vehicle deviates during landing, and can realize constant voltage and constant current output switching without communication between the transmitting plate side and the receiving plate side.

[0007] To solve the above technical problems, the application adopts the following technical scheme: an output switching type continuous arch bridge type CPT system, comprising an unmanned aerial vehicle and a platform; further comprising a wireless power transmitting module, a wireless power receiving module and a coupling mechanism;

[0008] The wireless power transmitting module comprises a direct current input power supply, a high-frequency inverter circuit, and a transmitting side compensation circuit.

[0009] The wireless power receiving module comprises a receiving side compensation circuit, a rectifier circuit, a filter capacitor, a filter inductor, and a load resistor.

[0010] The coupling mechanism comprises a wireless power transmitting plate, a wireless power receiving plate, and a coupling circuit.

[0011] In the output switching type continuous arch bridge type CPT system, the wireless power transmitting plate is installed on the platform, and the wireless power receiving plate is installed at the bottom of the unmanned aerial vehicle; the wireless power transmitting plate is in the shape of an arch bridge in the longitudinal direction, and is composed of a plurality of identical waves in the transverse direction, and the top of the arch bridge has an opening with a distance of L2; the wireless power receiving plate has the same structure as the single concave wave of the wireless power transmitting plate, and also has an opening at the top with a distance of L2; the single concave wave comprises a semicircle and a 1 / 2 semicircle connected to the two sides of the semicircle, and the radii of the semicircles are the same; the radius of the semicircle of the wireless power receiving plate is smaller than the radius of the semicircle of the wireless power transmitting plate.

[0012] In the output switching type continuous arch bridge type CPT system, the high-frequency inverter circuit comprises a first MOS tube (M1), a second MOS tube (M2), a third MOS tube (M3), and a fourth MOS tube (M4); the transmitting side compensation circuit comprises a first inductor L1, a second inductor L2, and a first capacitor C1; the coupling circuit comprises a first coupling capacitor C s1 and a second coupling capacitor C s2 ; the receiving side compensation circuit comprises a third inductor L3, a first switch (SW1), a second capacitor C2, a third capacitor C3, and a second switch (SW2); the rectifier circuit comprises a first diode (D1), a second diode (D2), a third diode (D3), and a fourth diode (D4); the filter circuit comprises a filter inductor L f and a filter capacitor C f ; the load resistor is R L ; the direct current input power supply U dc is connected in parallel with the high-frequency inverter circuit; one end of the first inductor L1 and one end of the first capacitor C1 are connected to the high-frequency inverter circuit; the other end of the first inductor L1 is connected to the other end of the first capacitor C1 and one end of the second inductor L2; the other end of the second inductor L2 is connected to one end of the first coupling capacitor C s1 ; the other end of the first coupling capacitor C s1one end of the third inductor L3, one end of the first switch SW1 and one end of the second capacitor C2, the other end of the second capacitor C2 is connected to one end of the second switch SW2 and one end of the third capacitor C3, the other end of the third capacitor C3 is connected to the other end of the first switch SW1 and the other end of the third inductor L3, the other end of the second switch SW2 is connected to one end of the second coupling capacitor C s2 , the other end of the second coupling capacitor C s2 is connected to one end of the first capacitor C1, the other end of the third inductor L3 and the other end of the second switch SW2 are connected to the rectifier circuit respectively.

[0013] In the above output switching type continuous arch bridge type CPT system, the second inductor L2 includes a first part L 2a of the second inductor and a second part L 2b of the second inductor, and L 2a +L 2b =L2; the first inductor L1, the first part L 2a of the second inductor and the first capacitor C1 constitute a T network of the transmitting side compensation circuit.

[0014] In the above output switching type continuous arch bridge type CPT system, the first coupling capacitor C s1 and the second coupling capacitor C s2 are combined into a series coupling capacitor C s ; the second part L 2b of the second inductor and the series coupling capacitor C s constitute a coupling circuit.

[0015] In the above output switching type continuous arch bridge type CPT system, the third inductor L3, the first switch SW1, the second capacitor C2, the third capacitor C3 and the second switch SW2 constitute a receiving side compensation circuit.

[0016] In the above output switching type continuous arch bridge type CPT system, when the first switch SW1 is closed and the second switch SW2 is opened, the receiving side compensation circuit is a zero impedance circuit; when the first switch SW1 is opened and the second switch SW2 is closed, the receiving side compensation circuit is a π network.

[0017] A switching method of an output switching type continuous arch bridge type CPT system, comprising: a T network converts a constant input voltage into a constant output current or converts a constant input current into a constant output voltage while filtering harmonics;

[0018]

[0019] When the element parameters of the T network satisfy formula (1), constant output is achieved, and it is in a purely resistive state; the T network converts the equivalent input constant voltage source after inversion The output voltage is converted into constant current output;

[0020] The second part L of the second inductance 2b The series coupling capacitor C is used to compensate s And the mathematical relationship satisfies the following formula

[0021]

[0022] When the system is constant current output, the first switch SW1 is closed, the second switch SW2 is opened, the third inductance L3, the second capacitor C2 and the third capacitor C3 are short-circuited, the receiving side compensation circuit is a zero impedance circuit, the system carries out constant current output, omega is the system working angular frequency, which satisfies the relationship with the system working frequency f: omega = 2 * pi * f, and j represents the imaginary part of the phasor;

[0023]

[0024] When the system is constant voltage output, the first switch SW1 is opened, the second switch SW2 is closed, and the second capacitor C2, the third capacitor C3 and the third inductance L3 satisfy formula (3), the receiving side compensation circuit is a pi-type network, which converts the constant current output by the coupling circuit into constant output voltage, the receiving side compensation circuit is purely resistive, and the system carries out constant voltage output.

[0025] Compared with the prior art, the present application has the following advantages:

[0026] Compared with the existing constant voltage and constant current output switching type CPT system, the present application has the following obvious advantages: 1. The wireless power coupling mechanism not only has an auxiliary positioning function but also has outstanding anti-deviation performance. 2. The cross-coupling capacitance value of the wireless power coupling mechanism is very small relative to the main coupling capacitance value, so the influence of the cross-coupling capacitance does not need to be considered when designing the system, thereby simplifying the complexity of the system design. 3. The system has the advantage of being lightweight, and the receiving side compensation circuit only uses three passive devices and two switching switches. 4. When the constant voltage and constant current output is switched, communication between the wireless power transmission module and the receiving module is not needed. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a coupling mechanism overall view for the embodiment of the present application;

[0028] Figure 2 It is a coupling mechanism front view for the embodiment of the present application;

[0029] Figure 3 It is a coupling mechanism left view for the embodiment of the present application;

[0030] Figure 4 It is a coupling mechanism single wave section view for the embodiment of the present application;

[0031] Figure 5Figure 1 is a general view of a receiving plate for an embodiment of the present application;

[0032] Figure 6 Figure 2 is a top view of a coupling mechanism for an embodiment of the present application with zero offset;

[0033] Figure 7 Figure 3 is a top view of a coupling mechanism for an embodiment of the present application with one wave offset;

[0034] Figure 8 Figure 4 is a top view of a coupling mechanism for an embodiment of the present application with two wave offset;

[0035] Figure 9 Figure 5 is a circuit diagram of a CPT system for an embodiment of the present application;

[0036] Figure 10 Figure 6 is an equivalent simplified circuit diagram of a CPT system for an embodiment of the present application;

[0037] Figure 11 Figure 7 is an equivalent simplified circuit diagram of a constant current output for an embodiment of the present application;

[0038] Figure 12 Figure 8 is a constant current output diagram for an embodiment of the present application;

[0039] Figure 13 Figure 9 is an equivalent simplified circuit diagram of a constant voltage output for an embodiment of the present application;

[0040] Figure 14 Figure 10 is a constant voltage output diagram for an embodiment of the present application;

[0041] Figure 15 Figure 11 is an input current fluctuation diagram when output switching for an embodiment of the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0043] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0044] The present application will be further described below in conjunction with specific embodiments, but is not limited to the present application.

[0045] In order to improve the anti-offset capability of the CPT system and realize the purpose of constant voltage and constant current output switching, the embodiment proposes an output switching type continuous arch bridge CPT system suitable for unmanned aerial vehicles. The system has the advantages of simple control, easy implementation, no communication between the transmitting side and the receiving side of the CPT system, effectively improving the anti-offset capability of the system, and realizing constant voltage and constant current output switching.

[0046] The embodiment is realized by the following technical scheme, an output switching type continuous arch bridge CPT system, comprising a wireless power transmission module, a wireless power receiving module and a coupling mechanism.

[0047] The wireless power transmission module comprises a direct current input power supply, a high-frequency inverter circuit and a transmitting side compensation circuit.

[0048] The wireless power receiving module comprises a receiving side compensation circuit, a rectifier circuit, a filter capacitor, a filter inductor and a load resistor.

[0049] The coupling mechanism comprises a wireless power transmitting plate, a wireless power receiving plate and a coupling circuit.

[0050] The embodiment plays an auxiliary positioning role by constructing a continuous arch bridge coupling mechanism. The unmanned aerial vehicle can utilize its own gravity to avoid landing offset caused by its own landing error. On the other hand, it plays a role in increasing the main coupling capacitance value and reducing the cross coupling capacitance value.

[0051] The wireless power transmitting plate is installed on the platform, and the wireless power receiving plate is installed at the bottom of the unmanned aerial vehicle. The wireless power transmitting plate is in the shape of an arch bridge in the longitudinal direction, and is composed of a plurality of identical waves in the transverse direction. The top of the arch bridge has an opening with a distance of L2. The wireless power receiving plate has the same structure as a single recessed wave of the wireless power transmitting plate, and also has an opening at the top with a distance of L2. The single recessed wave comprises a semicircle and a 1 / 2 semicircle connected to the two sides of the semicircle, and the radii of the semicircles are the same. The radius of the semicircle of the wireless power receiving plate is smaller than the radius of the semicircle of the wireless power transmitting plate. The opening divides the transmitting plate into a left transmitting plate P1 and a right transmitting plate P2, and divides the receiving plate into a left receiving plate P3 and a right receiving plate P4. The coupling capacitances of the left transmitting plate P1 and the left receiving plate P3, and the right transmitting plate P2 and the right receiving plate P4 are the main coupling capacitances, as shown in the first coupling capacitance C Figure 9 . s1 s2 .

[0052] The coupling mechanism is shown in the front view as Figure 2 , the transmitting plate and the receiving plate present an arch shape in the front view, and can automatically correct the left and right direction positions by utilizing the gravity of the unmanned aerial vehicle when landing.

[0053] ​Embodiment 1

[0054] The design of the arch bridge radius R, height H, span L, arch bridge top and bottom difference L1 and arch bridge middle opening distance L2 of the wireless power transmitting electrode plate is arbitrary. In this embodiment, R is designed as 68 mm, H is designed as 70 mm, L is designed as 152 mm, L1 is designed as 20 mm and L2 is designed as 10 mm.

[0055] The left view of the wireless power transmitting electrode plate and the wireless power receiving electrode plate of the coupling mechanism is shown in FIG. 2, in principle, the design of the width W of the transmitting electrode plate can be arbitrary, and in this embodiment, W is set as 200 mm. The transmitting electrode plate and the receiving electrode plate are in a wavy shape in the left view, in principle, the wave can be infinite, considering the actual size of the physical object, the transmitting electrode plate of this embodiment is connected by 5 waves, the 5 waves are completely consistent, composed of semicircles with a certain size, and the single wave cross section schematic diagram is shown in FIG. 3, the radius R1 thereof is 10 mm. Figure 3 Figure 4

[0056] The overall diagram of the receiving electrode plate is shown in FIG. 4, which is consistent with the single wave of the transmitting electrode plate in configuration, and only the radius of the cross section schematic diagram is slightly smaller than R1, which is 9.8 mm. Figure 5

[0057] Since the receiving electrode plate is designed as a concave shape, each wave of the transmitting electrode plate naturally becomes a clamping groove of the receiving electrode plate, when the unmanned aerial vehicle lands, the self-gravity factor can be used to make the unmanned aerial vehicle receiving electrode plate clamped into the clamping groove (wave) of the transmitting electrode plate, which can avoid the rotation deviation of the unmanned aerial vehicle when landing.

[0058] When the unmanned aerial vehicle receiving electrode plate is in a zero deviation position, as shown in FIG. 5. The coupling capacitance of the left transmitting electrode plate P1 and the right transmitting electrode plate P2, the left transmitting electrode plate P1 and the right receiving electrode plate P4, the right transmitting electrode plate P2 and the left receiving electrode plate P3, and the left receiving electrode plate P3 and the right receiving electrode plate P4 is cross coupling capacitance. At this time, the coupling capacitance value between each electrode plate is shown in Table 1. Figure 6

[0059] Table 1: Coupling capacitance value pF when zero deviation

[0060] P1 P2 P3 P4 P1 - -4.2166 -254.92 -0.1559 P2 -4.2166 - -0.1562 -254.96 P3 -254.92 -0.1562 - -0.1814 P4 -0.1559 -254.96 -0.1814 -

[0061] ​​​​Table 1 shows that the coupling mechanism scheme proposed in this embodiment 1 can ignore the existence of cross-coupling capacitance when the receiving plate is zero offset, which is embodied in that the main coupling capacitance value between the left transmitting plate P1 and the left receiving plate P3 and the right transmitting plate P2 and the right receiving plate P4 is almost equal, about 254.9 pF, and the maximum cross-coupling capacitance value between the left transmitting plate P1 and the right transmitting plate P2, the left transmitting plate P1 and the right receiving plate P4, the left receiving plate P3 and the right transmitting plate P2, and the left receiving plate P3 and the right receiving plate P4 is about 4.2 pF, accounting for only 1.6% of the main coupling capacitance.

[0062] When the receiving plate of the UAV is in a wave offset position, as shown in Figure 7 , the coupling capacitance value between each plate is shown in Table 2.

[0063] Table 2 Coupling capacitance value pF when offset by one wave

[0064] P1 P2 P3 P4 P1 - -4.21 -254.94 -0.1577 P2 -4.21 - -0.1581 -254.97 P3 -254.94 -0.1581 - -0.1816 P4 -0.1577 -254.94 -0.1816 -

[0065] Table 3 Coupling capacitance value pF when offset by two waves

[0066] P1 P2 P3 P4 P1 - -4.1283 -253.87 -0.1864 P2 -4.1283 - -0.1581 -253.95 P3 -253.87 -0.1869 - -0.2097 P4 -0.1864 -253.95 -0.2097 -

[0067] Table 2 and Table 3 data show that when the receiving plate and the transmitting plate are offset, the main coupling capacitance and the cross-coupling capacitance do not change substantially. The maximum absolute value of the coupling capacitance change is shown in Table 4.

[0068] Table 4 Maximum absolute value of coupling capacitance change pF

[0069] P1 P2 P3 P4 P1 - 0.09 1.05 0.03 P2 0.09 - 0.03 1.01 P3 1.05 0.03 - 0.03 P4 0.03 1.01 0.03 -

[0070] Table 4 data shows that the anti-offset performance of the coupling mechanism scheme in embodiment 1 is outstanding, which is embodied in that when the receiving plate is offset, the maximum absolute difference of the main coupling capacitance and the cross-coupling capacitance caused by the offset is not more than 1.05 pF, that is, the strong anti-offset performance of the coupling mechanism is realized.

[0071] The maximum proportion of cross-coupling capacitance to main coupling capacitance (including offset) is shown in Table 5.

[0072] Table 5 Maximum proportion of cross-coupling capacitance to main coupling capacitance

[0073] Cross-coupled capacitance P1 and P2 P1 and P4 P3 and P2 P3 and P4 Maximum percentage 1.65％ 0.07％ 0.07％ 0.08％

[0074] The data in Table 5 shows that the existence of the cross-coupling capacitance can be ignored in the receiving plate of Example 1 under various offset conditions, which is specifically manifested as: the maximum cross-coupling capacitance value of the coupling mechanism accounts for 1.65% of the main coupling capacitance value, and the existence of the cross-coupling capacitance can be ignored in actual use, so the coupling capacitance can be equivalent to a series mode in the circuit, such as Figure 10 the second capacitor C2 in the T2 part.

[0075] The coupling mechanism of the embodiment meets the performance requirements of the system high anti-offset, and greatly reduces the cross-coupling capacitance value, providing a basis for the establishment of the system circuit.

[0076] In order to ensure the light weight of the system, on the basis of constructing a high-performance coupling mechanism, an output switching type CPT circuit is proposed, as shown in Figure 9 , which includes a direct current input power supply U dc , a high-frequency inverter circuit composed of a first MOS tube M1, a second MOS tube M2, a third MOS tube M3 and a fourth MOS tube M4, a first inductor L1, a second inductor L2, a first capacitor C1, a first coupling capacitor C s1 , a second coupling capacitor C s2 , a third inductor L3, a first switch SW1, a second capacitor C2, a third capacitor C3, a second switch SW2, a first diode D1, a second diode D2, a third diode D3 and a fourth diode D4, a rectifier circuit, a filter inductor L f and a filter capacitor C f , and a load R L ; the direct current input power supply U dc is connected in parallel with the high-frequency inverter circuit, one end of the first inductor L1 and one end of the first capacitor C1 are connected to the high-frequency inverter circuit, the other end of the first inductor L1 is connected to the other end of the first capacitor C1 and one end of the second inductor L2, the other end of the second inductor L2 is connected to one end of the first coupling capacitor C s1 , the other end of the first coupling capacitor C s1 is connected to one end of the third inductor L3, one end of the first switch SW1 and one end of the second capacitor C2, the other end of the second capacitor C2 is connected to one end of the second switch SW2 and one end of the third capacitor C3, the other end of the third capacitor C3 is connected to the other end of the first switch SW1 and the other end of the third inductor L3, the other end of the second switch SW2 is connected to one end of the second coupling capacitor C s2 , the other end of the second coupling capacitor C s2 is connected to one end of the first capacitor C1, and the other end of the third inductor L3 and the other end of the second switch SW2 are connected to the rectifier circuit.

[0077] In order to simplify the analysis, the circuit shown in Figure 9 is equivalent toFigure 10 The circuit shown has an equivalent input constant voltage source after inversion that is equivalent to... The second inductor L2 is equivalent to the first part L of the second inductor connected in series. 2a The second part L of the second inductor 2b And satisfy L 2a +L 2b =L2; Main coupling capacitor, first coupling capacitor C s1 Second coupling capacitor C s2 Equivalent to a series coupling capacitor C s The rectifier circuit, filter inductor, filter capacitor, and load are considered as equivalent resistance R.

[0078] The transmitter-side compensation circuit is Figure 10 The T-type network with constant output characteristics shown in section T1 includes a first inductor L1, a first capacitor C1, and a second inductor first part L. 2a The resulting T-shaped network.

[0079] The receiving side compensation circuit is Figure 10 The T3 section is controlled by two switches, SW1 (first shape) and SW2 (second shape), to switch between a zero-impedance circuit and a π-type network with constant output characteristics. Specifically, the receiver-side compensation circuit consists of a third inductor L3, a first switch SW1, a second capacitor C2, a third capacitor C3, and a second switch SW2.

[0080] When the first switch SW1 is closed and the second switch SW2 is open, the receiving-side compensation circuit is a zero-impedance circuit; when the first switch SW1 is open and the second switch SW2 is closed, the receiving-side compensation circuit is a π-type network.

[0081] Coupled circuits such as Figure 10 As shown in section T2, the main coupling capacitor and the first coupling capacitor C s1 Second coupling capacitor C s2 Equivalent to a series coupling capacitor C s .

[0082] The specific implementation scheme for switching between constant voltage and constant current output is as follows:

[0083] The first inductor L1, the first capacitor C1, and the first part of the second inductor L on the transmitting side 2a The constructed T-shaped network, such as Figure 10 As shown in section T1, this T-type network can filter out harmonics while converting a constant input voltage into a constant output current or a constant input current into a constant output voltage.

[0084]

[0085] When the component parameters of the T-type network satisfy formula (1), it can achieve constant output characteristics while ensuring that this part is always in a zero-phase angle (ZPA) state, i.e., a purely resistive state. At this time, the T1 region will be a constant voltage source. The output voltage is converted into a constant current output; ω is the system operating angular frequency, which satisfies the relationship with the system operating frequency f: ω=2πf, j represents the imaginary part of the phasor.

[0086] The second part L of the second inductor 2a Used to compensate for series coupling capacitor C s ,like Figure 10 As shown in part T2, the mathematical relationship between the two satisfies formula (2):

[0087]

[0088] At this time, part T2 is in a series resonant state with zero impedance, and does not have any effect on the constant current output by part T1.

[0089] To ensure a lightweight design on the receiving side, this embodiment proposes an output switching scheme with two switches and three passive devices. The receiving-side compensation circuit employs a zero-impedance network and a π-type network with constant output characteristics. The zero-impedance network does not transform the constant current output in region T2, resulting in a constant current output. The π-type network converts the constant current output in region T2 into a constant voltage output, resulting in a constant voltage output.

[0090] When the system requires constant current output, the first switch SW1 is closed, the second switch SW2 is open, and the third inductor L3, the third capacitor C3, and the fourth capacitor C4 are short-circuited. At this time, section T3 is a zero-impedance circuit and does not change the current output in region T2. ​​The system then outputs a constant current. The system circuit at this time is as follows: Figure 11 As shown. The output current is as follows. Figure 12 As shown, during the constant current stage, the load experienced a sudden change from 50Ω to 70Ω and then from 70Ω to 60Ω, while the current remained basically at 1.2A. The system switched to constant voltage output state, and the steady-state output current was 1A.

[0091]

[0092] When the system requires constant voltage output, the first switch SW1 is open, the second switch SW2 is closed, and the third capacitor C3, the fourth capacitor C4, and the third inductor L3 satisfy formula (3). In this case, region T3 forms a π-type network, converting the constant current output from region T2 into a constant output voltage. At this time, region T3 is purely resistive, and the system outputs constant voltage. The system circuit is as follows: Figure 13 As shown. The output voltage is as follows.Figure 14 As shown in the figure, in the constant current stage, the load resistance is 50Ω, and the steady output voltage is 62V; in the constant voltage stage, the load experiences a sudden change from 50Ω to 70Ω and from 70Ω to 60Ω, and the voltage basically remains 61.5V.

[0093] In this embodiment, the time point of 5ms is set as the output switching time point, at this time, the first switch SW1 is switched from the closed state to the open state, and the second switch SW2 is simultaneously switched from the open state to the closed state. Before and after the switching of the switches, the system load resistance remains 50Ω, and the input current of the system is as shown in the figure. Figure 10 The steady state amplitude of the input current of the system before the switching is 2.36A, the maximum transient peak of the input current after the switching is 2.5A, and the steady state amplitude of the input current after the switching is 2.1A.

[0094] The above are only the preferred embodiments of the present application, and do not limit the implementation manners and protection scope of the present application. It should be realized by those skilled in the art that any equivalent replacement and obvious change made according to the contents of the present application should be included in the protection scope of the present application.

Claims

1. An output switch-type continuous arch bridge type CPT system comprising a drone and a platform; characterized in that, The wireless power transmission module, the wireless power receiving module and the coupling mechanism are included; The wireless power transmitting module includes a direct current input power supply U dc A high-frequency inverter circuit and a transmitting-side compensation circuit The wireless power receiving module includes a receiving side compensation circuit, a rectifier circuit, a filter capacitor, a filter inductor and a load resistor; The coupling mechanism includes a wireless power transmission plate, a wireless power receiving plate and a coupling circuit; The wireless power transmission plate is installed on a platform, and the wireless power receiving plate is installed at the bottom of the unmanned aerial vehicle; the wireless power transmission plate is in the shape of an arch bridge in the longitudinal direction, is composed of a plurality of same waves in the transverse direction, and has an opening at the top of the arch bridge, the opening distance being L2; the wireless power receiving plate has the same structure as a single recessed wave of the wireless power transmission plate, and also has an opening at the top, the opening distance being L2; the single recessed wave includes a semicircle and 1 / 2 semicircles connected to two sides of the semicircle respectively, and the radii of the semicircles are the same; The radius of the semicircle of the wireless power receiving plate is smaller than the radius of the semicircle of the wireless power transmission plate.

2. The output switching type continuous arch bridge CPT system according to claim 1, characterized in that, The high-frequency inverter circuit includes the first MOSFET ( M 1) Second MOSFET ( M 2) Third MOSFET ( M 3) and the fourth MOSFET ( M 4) The transmitter-side compensation circuit includes a first inductor. L 1. Second inductor L 2 and the first capacitor C 1; The coupling circuit includes a first coupling capacitor. C s1 Second coupling capacitor C s2 The receiving-side compensation circuit includes a third inductor. L 3. First switch ( SW 1) Second capacitor C 2. Third capacitor C 3 and the second switch ( SW 2); The rectifier circuit includes the first diode ( D 1) Second diode ( D 2) Third diode ( D 3) and the fourth diode ( D 4) The filter circuit includes a filter inductor. L f and filter capacitor C f The load resistance is R L DC input power supply U dc The first inductor is connected in parallel with the high-frequency inverter circuit. L One end of 1 and the first capacitor C One end of 1 is connected to a high-frequency inverter circuit, and the first inductor L The other end of 1 is connected to the first capacitor. C The other end of 1 and the second inductor L One end of 2 is connected to the second inductor. L The other end of 2 is connected to the first coupling capacitor. C s1 One end, the first coupling capacitor C s1 The other end is connected to the third inductor. L 3 at one end, the first switch ( SW 1) One end and the second capacitor C 2, one end, the second capacitor C The other end of 2 is connected to the second switch ( SW 2) One end and the third capacitor C One end of 3, the third capacitor C The other end of 3 is connected to the first switch ( SW the other end of the third inductor L the other end of the second switch (3) SW the other end of the second coupling capacitor (2) is connected to the rectifier circuit C s2 the other end of the second coupling capacitor (2) is connected to the rectifier circuit C s2 the other end of the second coupling capacitor (2) is connected to the rectifier circuit C the other end of the third inductor L the other end of the second switch (3) SW the other end of the second switch (3) 3. The output-switching continuous-arch bridge type CPT system according to any one of claims 2, characterized by, second inductor L 2 first part comprising the second inductor L 2a and second part of the second inductor L 2b , and L 2a + L 2b = L 2 first inductor L 1 first part of the second inductor L 2a and first capacitor C 1 forms a T-network of the transmit-side compensation circuit.

4. The output-switching continuous-arch bridge type CPT system according to any one of claims 3, wherein a first coupling capacitor C s1 a second coupling capacitor C s2 combined to form a series coupling capacitor C s a second portion of the second inductor L 2b and the series coupling capacitor C s to form a coupling circuit.

5. The output-switching continuous-arch bridge type CPT system according to any one of claims 4, wherein third inductor L 3, first switch SW 1), second capacitor C 2, third capacitor C 3, second switch SW 2) constitutes a receiving side compensation circuit.

6. The output-switching continuous-arch bridge type CPT system according to any one of claims 5, wherein The first switch ( SW 1) is closed, the second switch ( SW 2) is open, the receiving side compensation circuit is a zero impedance circuit; the first switch ( SW 1) is open, the second switch ( SW 2) is closed, the receiving side compensation circuit is a π type network.

7. A switching method of an output switching type continuous arch bridge type CPT system, which is implemented by the output switching type continuous arch bridge type CPT system according to any one of claims 1 to 6, characterized in that, The method includes: a T-type network converts a constant input voltage into a constant output current or converts a constant input current into a constant output voltage while filtering harmonics; （1） When the element parameters of the T-type network satisfy formula (1), constant output is achieved, and it is in a purely resistive state; the T-type network converts the equivalent input constant voltage source after inversion into a constant current output The output voltage is converted into a constant current output, ω is the system operating angular frequency, which is related to the system operating frequency f satisfies the relationship: ω =2π f , j represents the imaginary part of the phasor; Second portion of the second inductor L 2b To compensate for series coupling capacitance C s , and both mathematical relationship satisfies the following formula （2） When the system constant current output, the first switch (Q1) SW 1) is closed, the second switch (Q2) SW 2) is open, the third inductor (L3) L 3, the second capacitor (C2) C 2, the third capacitor (C3) C 3 short circuit, the receiving side compensation circuit is zero impedance circuit, the system constant current output; （3） When the system outputs constant voltage, the first switch (S1) is turned off, the second switch (S2) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. SW 1) is turned off, the second switch (S2) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. SW 2) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. C 2) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. C 3) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. L 3) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal. When the system outputs constant voltage, the first switch (S1) is turned off, the second switch (S2) is turned on, and the second capacitor (C2) is charged to the voltage of the input signal.

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