Wireless charging vehicle secondary side current feedback system based on double-sided lcc and coil integration

Abstract

The application provides a wireless charging automobile secondary side current feedback system based on double-sided LCC and coil integration, a secondary side integrated inductance coil is wound in an energy receiving coil, a current feedback receiving coil is wound in an energy transmitting coil, and the energy transmitting coil and the energy receiving coil are both arranged as Q type coils; the secondary side integrated inductance coil and the current feedback receiving coil are both arranged as "8" type coils; the energy transmitting coil is connected to a wireless charging transmitting circuit containing a primary side LCC compensation network, the energy receiving coil is connected to a wireless charging receiving circuit containing a secondary side LCC compensation network, the secondary side LCC compensation network is composed of the secondary side integrated inductance coil and a capacitor C f2 and a capacitor C s , and the current feedback receiving coil is connected with a feedback current extraction circuit. The application realizes power transmission from the primary side to the secondary side and signal feedback from the secondary side to the primary side, and the two channels do not affect each other, so that the secondary side current feedback can be quickly realized, local closed-loop control is facilitated, and the system output power is stable.

Description

TECHNICAL FIELD

[0001] The present application relates to electric vehicle wireless charging technology, in particular to a wireless charging vehicle secondary side current feedback system based on double-sided LCC and coil integration. BACKGROUND

[0002] Wireless power transfer (WPT) is a technology that transfers electric energy through magnetic field, electric field, laser and microwave medium, etc. to achieve non-electric contact transmission of electric energy. This technology can effectively solve the problems of limited flexibility and safety hazards caused by traditional wired power supply. At present, in the application fields of electric vehicles, consumer electronic products and household appliances, domestic and foreign experts and scholars have carried out research on this technology and obtained a lot of theoretical results.

[0003] In the existing wireless power transfer system, in order to ensure that the wireless power transfer system can operate normally, it is necessary to establish primary and secondary side communication. When the secondary side load or circuit is abnormal, information is transmitted to the primary side for control or shutdown. At present, the communication between the primary and secondary sides in the wireless power transfer system generally adopts WIFI, ZigBee and other communication methods. The traditional communication method often needs to increase additional communication implementation, and the system design cost is high. Moreover, in the complex electromagnetic environment of high power, the conventional communication method is often easily affected, and the system stability is not strong. SUMMARY

[0004] Therefore, the present application provides a wireless charging vehicle secondary side current feedback system based on double-sided LCC and coil integration, which realizes the same frequency feedback of the secondary side current under the premise of not affecting the normal power transmission through the integrated design of the additional coupling channel, so that the local closed-loop control can be quickly realized.

[0005] In order to achieve the above purpose, the specific technical solutions adopted by the present application are as follows:

[0006] A wireless charging vehicle secondary side current feedback system based on double-sided LCC and coil integration, the key lies in that a secondary side integrated inductor coil is wound in an energy receiving coil of a wireless charging vehicle, and a current feedback receiving coil is wound in an energy transmitting coil of a primary side, wherein the energy transmitting coil and the energy receiving coil are both set as Q-shaped coils, and are mutually coupled and adapted in shape and size; the secondary side integrated inductor coil and the current feedback receiving coil are both set as "8"-shaped coils, and are mutually coupled and adapted in shape and size.

[0007] The energy transmitting coil is connected to a wireless charging transmitting circuit comprising a primary LCC compensation network, and the energy receiving coil is connected to a wireless charging receiving circuit comprising a secondary LCC compensation network, wherein the secondary LCC compensation network is composed of the secondary integrated inductor coil and a capacitor C f2 and a capacitor C s The current feedback receiving coil is connected to a feedback current extraction circuit.

[0008] Optionally, the wireless charging receiving circuit further comprises a first rectification filter circuit and a power consumption load.

[0009] Optionally, the feedback current extraction circuit comprises a compensation capacitor Cs1 connected to the current feedback receiving coil, a second rectification filter circuit and a feedback signal sampling resistor.

[0010] Optionally, the primary LCC compensation network is composed of an inductor L f1 , a capacitor C f1 and a capacitor C p The wireless charging transmitting circuit further comprises a DC power supply and a high-frequency inverter.

[0011] Optionally, the energy transmitting coil and the current feedback receiving coil are wound on the same plane, and the energy receiving coil and the secondary integrated inductor coil are wound on the same plane.

[0012] Optionally, the mutual inductance between the energy transmitting coil and the energy receiving coil is M1, and the mutual inductance between the secondary integrated inductor coil and the current feedback receiving coil is M2, and the constraint relationship between them is:

[0013] M1=kM2, wherein k is a proportional coefficient, and the value range of k is 10.5-18.6.

[0014] Optionally, the system further comprises a power regulation system, which obtains the pickup current of the current feedback receiving coil through the feedback current extraction circuit, calculates the mutual inductance between the current energy transmitting coil and the energy receiving coil, and then performs PID regulation on the power supply voltage in the wireless charging transmitting circuit by subtracting the mutual inductance under the standard working condition, so as to stabilize the system output power

[0015] The effects of the present application are as follows:

[0016] The application provides a wireless charging automobile secondary side current feedback system based on double-sided LCC and integrated coil, an additional coupling channel is formed by arranging the integrated coil, so that the system can realize power transmission from the primary side to the secondary side and signal feedback from the secondary side to the primary side, the two channels do not affect each other, the wireless charging automobile secondary side current feedback can be quickly realized, local closed-loop control is facilitated, and the system output power is stabilized. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced.

[0018] Figure 1 It is a system circuit schematic diagram of the application.

[0019] Figure 2 It is a structure schematic diagram of the coupling mechanism adopted by the system in the embodiment.

[0020] Figure 3 It is a PID control block diagram of the system.

[0021] Figure 4 It is a control flowchart of the system.

[0022] Figure 5 It is the output power waveform of the system under different distances without increasing feedback control.

[0023] Figure 6 It is the output power waveform of the system under different distances with increasing feedback control, wherein Figure 6 The right graph is a partial enlarged view of the left graph. EMBODIMENT

[0024] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0025] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the present application should be the usual meanings understood by the skilled in the art to which the present application belongs.

[0026] For example, Figure 1 And Figure 2As shown, the embodiment provides a wireless charging vehicle secondary side current feedback system based on double-sided LCC and coil integration. A secondary side integrated inductance coil is wound in an energy receiving coil of a wireless charging vehicle. A current feedback receiving coil is wound in an energy transmitting coil of a primary side. The energy transmitting coil and the energy receiving coil are both provided as Q-shaped coils, and are coupled to each other and have shapes and sizes adapted to each other. The secondary side integrated inductance coil and the current feedback receiving coil are both provided as "8"-shaped coils, and are coupled to each other and have shapes and sizes adapted to each other.

[0027] The energy transmitting coil is connected to a wireless charging transmitting circuit including a primary side LCC compensation network. The energy receiving coil is connected to a wireless charging receiving circuit including a secondary side LCC compensation network. The secondary side LCC compensation network is composed of the secondary side integrated inductance coil and a capacitor C f2 and a capacitor C s The current feedback receiving coil is connected to a feedback current extraction circuit.

[0028] Through Figure 1 It can be seen that the system primary side and secondary side both adopt LCC resonance compensation network topology. The wireless charging transmitting circuit includes a direct current power supply U dc and switching tubes S1-S4 to form a voltage type full-bridge high frequency inverter. The primary side LCC compensation network is composed of an inductor L f1 , a capacitor C f1 , and a capacitor C p The wireless charging receiving circuit is also provided with a first rectification filter circuit and a power consumption load. The feedback current extraction circuit includes a compensation capacitor Cs1 connected to the current feedback receiving coil, a second rectification filter circuit, and a feedback signal sampling resistor, Figure 1 It can be seen that the diode D1, the diode D2, the diode D3, the diode D4, and the capacitor Co constitute the first rectification filter circuit. The diode D5, the diode D6, the diode D7, the diode D8, and the capacitor Co1 constitute the second rectification filter circuit. The power consumption load is equivalent to a resistor R L . The feedback signal sampling resistor is equivalent to a resistor R L1 Correspondingly, L f1 , C f1 , and C p are primary side resonance network compensation parameters. L f2 , C f2 , and C s are secondary side resonance network compensation parameters. L p and L s are self-inductances of the primary side coil and the secondary side coil. I f1 is an inverter output current. I f2 is a system output current. I p and I sare the primary and secondary coil currents, R L is the equivalent load, ω is the system operating frequency, and M1 is the mutual inductance between the primary and secondary coils.

[0029] In combination Figure 2 It can be seen that in specific implementation, the energy transmitting coil and the current feedback receiving coil are wound on the same plane, and the energy receiving coil and the secondary integrated inductor coil are wound on the same plane. It can be seen that the system adds a set of reverse signal transmission channel topology on the basis of the original main power transmission channel topology, forms a main power transmission coupling channel between the energy transmitting coil and the energy receiving coil, and forms a signal transmission coupling channel between the secondary integrated inductor coil and the current feedback receiving coil. The current feedback receiving coil and the secondary integrated inductor coil are designed as 8-shaped, so that the current feedback receiving coil only couples with the secondary integrated inductor coil, induces power from the resonant compensation inductor in the positive topology, and then transmits the current information of the secondary side to the primary side through the signal transmission channel, so as to realize the current feedback from the secondary side to the primary side through the additional coupling channel. Through system analysis, it can be concluded that:

[0030]

[0031]

[0032] According to the above model, comsol simulation is performed, and the inductance matrix and mutual inductance relationship table shown in Table 1 are obtained. It can be seen that when the primary and secondary coil distance is in the range of 15-25 cm, the ratio of the mutual inductance of the main and secondary coils to the mutual inductance of the signal coils gradually increases between 10.5-18.6. Therefore, the energy transmitting coil and the energy receiving coil are set as the main power coil, the mutual inductance between them is M1, the secondary integrated inductor coil and the current feedback receiving coil are set as the small power coil, the mutual inductance between them is M2, and the constraint relationship between them is:

[0033] M1=kM2, where k is a proportional coefficient, and the value range is 10.5-18.6.

[0034] Table 1: Mutual inductance relationship table of each coil under different distances

[0035]

[0036] According to the above relationship, in combination Figure 3 and Figure 4It can be concluded that a power adjusting system can be arranged in the system, the power adjusting system obtains the pickup current of the current feedback receiving coil through the feedback current extraction circuit, calculates the mutual inductance between the current energy transmitting coil and the energy receiving coil, and then performs PID adjustment on the power supply voltage in the wireless charging transmitting circuit by subtracting the mutual inductance under the standard working condition, so as to stabilize the system output power.

[0037] In order to further verify the feasibility and effectiveness of the above system, the following simulation system is built according to the system parameters shown in Table 2 to perform simulation experiments.

[0038] Table 2 System parameters

[0039]

[0040] The simulation results are shown in Figure 5 and Figure 6 When the system has no feedback, the output power at different distances is shown in Figure 5 It can be seen that the system power jumps with the change of distance, and the system output power reaches 103kW at 17cm, far exceeding the design requirement.

[0041] The detected signal is used as feedback control power voltage, and the system can stably output about 68kW, and after local amplification, it is shown in the right graph of Figure 6 Although there is a short pulse when the distance jumps, it can quickly maintain stability.

[0042] As can be seen from the above, the wireless charging vehicle secondary side current feedback system based on double LCC and integrated coil proposed in the application forms an additional coupling channel by setting an integrated coil, so that the system can realize power transmission from the primary side to the secondary side, and signal feedback from the secondary side to the primary side, and the two channels do not affect each other, and the wireless charging vehicle secondary side current feedback can be quickly realized, and local closed-loop control can be easily realized, so as to stabilize the system output power.

[0043] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the application, and not to limit them; although the application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can modify the technical solutions described in the above embodiments, or make equivalent replacement for part or all of the technical features; and such modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application, such changes should be covered in the scope of the claims and the description of the application.

Claims

1. A wireless charging automotive secondary-side current feedback system based on bilateral LCC and coil integration, characterized in that, A secondary integrated inductor coil is wound in the energy receiving coil of the wireless charging car, and a current feedback receiving coil is wound in the primary energy transmitting coil. The energy transmitting coil and the energy receiving coil are both Q-type coils, which are coupled to each other and have compatible shapes and sizes. The secondary integrated inductor coil and the current feedback receiving coil are both figure-eight coils, which are coupled to each other and have compatible shapes and sizes. The energy transmitting coil is connected to a wireless charging transmitting circuit containing a primary-side LCC compensation network, and the energy receiving coil is connected to a wireless charging receiving circuit containing a secondary-side LCC compensation network. The secondary-side LCC compensation network consists of the secondary-side integrated inductor coil and capacitor C. f2 and capacitor C s The current feedback receiving coil is connected to the feedback current extraction circuit. The feedback current extraction circuit includes a compensation capacitor Cs1 connected to the current feedback receiving coil, a second rectifier filter circuit, and a feedback signal sampling resistor.

2. The wireless charging vehicle secondary-side current feedback system based on bilateral LCC and coil integration according to claim 1, characterized in that, The wireless charging receiver circuit also includes a first rectifier filter circuit and a power load.

3. The wireless charging vehicle secondary-side current feedback system based on bilateral LCC and coil integration according to claim 1, characterized in that, The primary-side LCC compensation network consists of an inductor L f1 Capacitor C f1 Capacitor C p The wireless charging transmitter circuit also includes a DC power supply and a high-frequency inverter.

4. The wireless charging vehicle secondary-side current feedback system based on bilateral LCC and coil integration according to any one of claims 1-3, characterized in that, The energy transmitting coil and the current feedback receiving coil are wound on the same plane, and the energy receiving coil and the secondary integrated inductor coil are wound on the same plane.

5. The wireless charging vehicle secondary-side current feedback system based on bilateral LCC and coil integration according to claim 4, characterized in that, The mutual inductance between the energy transmitting coil and the energy receiving coil is The mutual inductance between the secondary integrated inductor coil and the current feedback receiving coil is The constraint relationship between the two is as follows: ,in It is a proportionality coefficient, and its value range is... .

6. The wireless charging vehicle secondary-side current feedback system based on bilateral LCC and coil integration according to claim 5, characterized in that, A power regulation system is also provided. The power regulation system obtains the pickup current of the current feedback receiving coil through the feedback current extraction circuit, calculates the mutual inductance between the current energy transmitting coil and the energy receiving coil, and then performs PID regulation on the power supply voltage in the wireless charging transmitting circuit by subtracting the mutual inductance under standard operating conditions, thereby stabilizing the system output power.

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