CN110768392B - An inductive coupling power transmission and full-duplex signal hybrid transmission circuit and method - Google Patents

Abstract

The invention discloses a circuit for inductive coupling power transmission and full-duplex signal mixed transmission. The primary side digital baseband signal is driven by AC variable frequency to generate a 2FSK modulation signal and forms an inductive energy coupling with the secondary side. The secondary side obtains the 2FSK modulation signal through current detection. Then, the 2FSK digital baseband signal sent forward by the primary side is obtained through signal processing means such as phase-locked loop or single-frequency tuning circuit. At the same time, the secondary side adopts ICPT power transmission and reception front-end dual resonant network, adding detuned capacitors and transistors. The turning on and off of the transistors corresponds to the change and maintenance of the original tuning capacitance, so that the resonant network is in detuned and resonant states respectively. , which plays the role of load modulation to change the equivalent load of the secondary side, which causes the change of the primary side inductor coil current and forms a 2ASK modulation signal. After signal processing, the 2ASK digital baseband signal sent in the reverse direction of the secondary side is obtained, thereby realizing a single channel Mixed transmission of power and full-duplex signals.

Description

An inductive coupling power transmission and full-duplex signal hybrid transmission circuit and method

Technical field

The invention belongs to the field of microelectronics and communication technology, and specifically relates to the field of inductively coupled power transmission (ICPT).

Background technique

Inductively coupled power transmission technology (ICPT) is based on the principle of electromagnetic induction and interacts with electrical energy through high-frequency magnetic fields. Air is used as the coupling medium between the transmitting coil and the pickup coil of the inductively coupled power transmission system, and the two can Compared with the traditional power supply system, the biggest feature of the inductive coupling power transmission system is that there is no direct physical connection between the power supply and the electrical equipment. It solves the problems and safety hazards of traditional power supply methods in special occasions (underwater or flammable and explosive occasions) and when equipment is rotating or moving, and can realize wireless transmission of electric energy.

Currently, the traditional signal transmission method in the ICPT system is to use a method of separate transmission of signals and electrical energy. This method not only increases the size and complexity of the inductive coupling mechanism, but also causes crosstalk between electrical energy transmission and signal transmission to a certain extent. question. Therefore, researchers have studied ICPT power signal hybrid transmission. Generally speaking, the signal transmission from the primary side to the secondary side is the forward transmission of the signal, and the transmission from the secondary side to the primary side of the ICPT system is the reverse transmission of data. For forward transmission, since the ICPT system power transmission transmits power from the primary side to the secondary side, the primary side power can be used as the carrier. The digital signal loads the signal onto the power through a certain modulation method, so that the transmitted power Has the characteristics of digital signals. The secondary power receiving end extracts the characteristics of the power and restores the digital signal while receiving the power.

However, in practical applications, it may be necessary to detect feedback information from electrical devices such as sensors on the secondary side in real time, which requires reverse transmission of signals in the ICPT system. The difference between reverse signal transmission and the aforementioned forward transmission is that in the ICPT system, the secondary side belongs to the receiving mechanism of electric energy and cannot send electric energy to the primary side. The two have a master-slave relationship, so the signal cannot be transmitted like the forward transmission. In this way, a certain characteristic of electrical energy is directly used as the modulation method to modulate the signal.

Contents of the invention

The purpose of the present invention is to propose an ICPT power and full-duplex signal hybrid transmission circuit and method using forward 2FSK frequency modulation and reverse 2ASK amplitude modulation without adding a separate signal transmission channel.

In order to achieve the above object, one technical solution of the present invention is to provide a primary side circuit of an ICPT single-channel power and full-duplex signal hybrid transmission system, which is characterized by including:

An AC variable frequency drive module is used to generate a 2FSK modulated signal based on the forward-sending digital baseband signal obtained by the primary-side microprocessor;

A resonant capacitor and an inductor coil are used to form the primary oscillation circuit;

A current detection module used to obtain the 2ASK modulated signal sent in the reverse direction by the secondary circuit;

A signal processing module used to obtain the digital baseband signal sent in the reverse direction by the secondary side circuit

Another technical solution of the present invention is to provide a secondary circuit of an ICPT single-channel power and full-duplex signal hybrid transmission system, which is characterized by including:

A dual-resonance point network, including a circuit composed of several capacitors and inductors. The resonant frequencies are the two frequencies generated by the AC variable frequency drive module of the above-mentioned primary-side circuit, used to simultaneously tune the primary-side 2FSK modulation signal;

A load power conversion module used to provide available power to the secondary components;

A current detection module is used to obtain the 2FSK modulation signal sent forward by the primary circuit;

A signal processing module used to obtain the 2FSK digital baseband signal sent forward by the primary circuit through a phase-locked loop or a single-frequency tuning circuit;

A detuning capacitor is used in series with a load modulation transistor and then in parallel at both ends of the double resonant point network to selectively detun the secondary resonant network;

A load modulation transistor is used to connect in series with the above-mentioned detuning capacitor and then in parallel at both ends of the dual resonance point network to selectively detun the secondary resonance network;

A microprocessor and a load modulation module in digital baseband are used to generate a 2ASK digital baseband signal according to protocol requirements and selectively control the opening and closing of the load modulation transistor.

Another technical solution of the present invention is to provide a method for mixed transmission of ICPT single-channel electric energy and full-duplex signals, which is characterized by adopting full-duplex forward 2FSK frequency modulation on the primary side and reverse 2ASK amplitude modulation on the secondary side. Signal transmission method: The above-mentioned primary side circuit generates a 2FSK modulation signal through AC variable frequency drive according to the forward sending digital baseband signal, and forms an inductive energy coupling with the above-mentioned secondary side circuit. The secondary side circuit obtains the 2FSK modulation signal through current detection, and then obtains the primary side The 2FSK digital baseband signal sent in the forward direction of the circuit; the secondary side circuit uses the load power conversion circuit to provide the power required for the operation of the secondary side components. By turning on and off the load modulation transistor controlled by the digital baseband, the original dual circuit is selectively On the basis of the resonant point network, the size of the resonant frequency is changed, so that the secondary resonant network is selectively in the detuned state and the resonant state, thereby obtaining different equivalent loads of the resonant network to achieve reverse 2ASK modulation of the load. The primary circuit passes The 2ASK modulated signal is obtained through current detection, and the 2ASK digital baseband signal sent in the reverse direction by the secondary circuit is obtained through signal processing; the dual resonance point network of the secondary circuit must have two resonance points, so that the reflected impedance change of the secondary circuit can be correctly reflected The changes in the current signal of the primary side circuit are not affected by the FM keying states 0 and 1 of the primary side.

Preferably, the secondary circuit obtains the 2FSK digital baseband signal sent forward by the primary circuit through a phase-locked loop or a single frequency tuning circuit.

Preferably, it specifically includes the following steps:

(1) The primary-side microprocessor of the primary-side circuit obtains a forward-sending digital baseband signal, and generates a 2FSK modulated signal through an AC variable frequency drive, which passes through the primary-side oscillation loop composed of the resonant capacitor of the primary-side circuit and the inductor coil of the primary-side circuit. , forming inductive energy coupling with the secondary circuit;

(2) The secondary circuit uses the load power conversion module to provide the power required for normal operation of the secondary components;

(3) The secondary circuit obtains the 2FSK modulated signal through current detection, and obtains the 2FSK digital baseband signal sent forward by the primary circuit;

(4) After the microprocessor of the secondary circuit performs relevant processing on the signal to be transmitted back to the primary circuit and converts it into a digital quantity, the load modulation module in the digital baseband transmits it to the load modulation transistor according to the requirements of the protocol;

(5) The load modulation transistor is in the corresponding on and off state according to the data transmitted from the load modulation module in the digital baseband;

(6) When the load modulation transistor is turned off, the detuning capacitor is disconnected from both ends of the dual resonance point network, that is, it is not connected in parallel with the dual resonance point network. At this time, it is still the dual resonance point network that determines the secondary resonance frequency. Therefore, the secondary resonance network is still in resonance;

(7) When the load modulation transistor is turned on, the detuned capacitor is connected to both ends of the inductor coil of the dual resonance point network, that is, in parallel with the dual resonance point network. At this time, it is the detuned capacitor and the dual resonance that determine the secondary resonance frequency. The point network is connected in parallel to form a total resonant network. Therefore, the secondary resonant network is in a detuned state at this time.

(8) The secondary impedance change caused by the transition between the resonant state and the detuned state of the secondary resonant network will be mapped to the primary circuit current. The primary circuit obtains the 2ASK modulation signal through current detection, and the secondary circuit reverse direction is obtained through signal processing. The 2ASK digital baseband signal is sent.

The unique advantage of the present invention is that it adopts forward 2FSK frequency modulation and reverse 2ASK amplitude modulation to realize ICPT full-duplex signal transmission. In the load 2ASK modulation process of ICPT signal mixed reverse transmission, by turning on and off the load modulation transistor controlled by the digital baseband, detuning capacitors are selectively connected in parallel based on the original dual resonance point network to make the secondary side resonate. The network selectively exits the detuned state and the resonance state to obtain different secondary equivalent loads to achieve load modulation. Among them, the secondary resonant network must have two resonance points, so that the reflected impedance change of the secondary side can be correctly reflected in the current signal change of the primary side without being affected by the FM keying states 0 and 1 of the primary side. In addition, since during the load reverse modulation process, the equivalent load on the secondary side changes from a smaller value at detuning to a larger value at resonance, there will be no shortage of power in the electric energy transmission.

Description of the drawings

Figure 1 shows the basic structure of the ICPT single-channel power and full-duplex signal hybrid transmission system of the present invention.

Numbers in the picture

101 is the primary side AC variable frequency drive module, 102 is the primary side resonant capacitor, 103 is the primary side inductor coil, 104 is the primary side current detection module, 105 is the primary side signal processing module, 106 is the secondary side dual resonance point network, 107 is Secondary side detuning capacitor, 108 is the secondary side load modulation transistor, 109 is the secondary side current detection module, 110 is the secondary side signal processing module, 111 is the digital baseband part of the secondary side resonant network, 112 is the secondary side microprocessor, 113 It is the secondary load power conversion module.

Detailed ways

The present invention will be further described below in conjunction with specific embodiments. It should be understood that these examples are only used to illustrate the invention and are not intended to limit the scope of the invention. In addition, it should be understood that after reading the teachings of the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the appended claims of this application.

The invention provides an ICPT single-channel electric energy and full-duplex signal hybrid transmission circuit and method that adopts primary-side forward 2FSK frequency modulation and secondary-side reverse 2ASK amplitude modulation. Based on the digital baseband signal sent in the forward direction, the primary side generates a 2FSK modulated signal through AC variable frequency drive and forms inductive energy coupling with the secondary side. The secondary side uses the load power conversion circuit to provide the power required for the operation of the secondary side components, and obtains 2FSK through current detection. Modulate the signal, and then obtain the 2FSK digital baseband signal sent forward by the primary side through signal processing means such as a phase-locked loop or a single-frequency tuning circuit. At the same time, the secondary side adopts ICPT power transmission transceiver front-end dual resonant network, adding detuning capacitance and load modulation transistor. The turning on and off of the transistor controlled by the digital baseband corresponds to the change and maintenance of the original tuning capacitance, making the resonant network respectively It is in the detuned and resonant state, which plays the role of load modulation to change the equivalent load of the secondary side. This causes the change of the primary side inductor coil current and forms a 2ASK modulation signal. After signal processing, the 2ASK digital baseband sent in the secondary side's reverse direction is obtained. signals, thereby achieving mixed transmission of single-channel electrical energy and full-duplex signals.

As shown in Figure 1, the single-channel power and full-duplex signal hybrid transmission circuit proposed by the present invention for the ICPT system has the primary side including: an AC variable frequency drive module 101, which is used to obtain the forward direction based on the primary side microprocessor. A digital baseband signal is sent to generate a 2FSK modulated signal; a resonant capacitor 102 and an inductor coil 103 are used to form the primary side oscillation circuit; a current detection module 104 is used to obtain the 2ASK modulated signal sent in the secondary side reversely; a signal processing module 105, used to obtain the digital baseband signal sent in the reverse direction by the secondary side. Its secondary side includes: a double resonant point network 106, including a number of circuits composed of capacitors and inductors. The resonant frequencies are the two frequencies generated by the primary side AC variable frequency drive module, which is used to simultaneously tune the primary side 2FSK modulation signal; a load power conversion Module 113 is used to provide available power to the secondary side components; a current detection module 109 is used to obtain the 2FSK modulated signal sent forward by the primary side; a signal processing module 110 is used to obtain the original signal through a phase-locked loop or a single frequency tuning circuit. A 2FSK digital baseband signal sent in the forward direction; a detuning capacitor 107, used to be connected in series with a load modulation transistor 108 and then in parallel at both ends of the dual resonant point network 106, so that the secondary side resonant network can be selectively detuned; a load The modulation transistor 108 is used to be connected in series with the above-mentioned detuning capacitor 107 and then in parallel at both ends of the dual resonant point network 106 to selectively detun the secondary resonant network; a microprocessor 112 and a digital baseband 111 for load modulation The module is used to generate the 2ASK digital baseband signal according to the protocol requirements, and selectively control the opening and closing of the above-mentioned load modulation transistor 108.

The above-described detuning capacitor 107 and the load modulation transistor 108 are connected in series and then in parallel at both ends of the dual resonance point network 106. When the load modulation transistor 108 is turned off, the detuning capacitor 107 has no effect, and the secondary resonant network is in a resonance state. When the load When the modulation transistor 108 is turned on, the detuning capacitor 107 acts. The detuning capacitor 107 is connected in parallel with the dual resonance point network 106 to change the resonant frequency of the secondary side total resonant network, thereby detuning the secondary side resonant network.

The above-mentioned load modulation module is a necessary core module in the digital baseband 111. According to the requirements of different protocols and different digital baseband structures, the digital baseband 111 may also include other core modules.

The above-mentioned two-resonance point network 106, a detuning capacitor 107 and a load modulation transistor 108 are the most basic components to realize the detuning method load modulation by changing the tuning capacitance. The other is to detun the secondary resonance network by changing the tuning capacitance. The method of achieving load modulation is thus equivalent to this method.

The working process of the ICPT single-channel electric energy and full-duplex signal hybrid transmission system of the present invention is as follows:

(1) The primary-side microprocessor obtains the forward-sending digital baseband signal, generates a 2FSK modulated signal through the AC variable frequency drive module 101, and forms an inductance with the secondary side through the resonant network composed of the primary-side resonant capacitor 102 and the primary-side inductor coil 103 Energy coupling.

(2) The secondary side uses the load power conversion module 113 to provide the power required for normal operation of the secondary side components.

(3) The secondary side obtains the 2FSK modulated signal through the current detection module 109, and obtains the 2FSK digital baseband signal sent forward by the primary side through the signal processing module 110 such as a phase-locked loop or a tuning circuit.

(4) After the secondary side microprocessor 112 performs relevant processing on the signal to be reversely transmitted back to the primary side and converts it into a digital quantity, the load modulation module in the digital baseband 111 transmits it to the load modulation transistor 108 according to the requirements of the protocol.

(5) The load modulation transistor 108 is in a corresponding on and off state according to the data transmitted from the load modulation module in the digital baseband 111.

(6) When the load modulation transistor 108 is turned off, the detuning capacitor 107 is disconnected from both ends of the secondary dual resonance point network 106, that is, it is not connected in parallel with the dual resonance point network. At this time, the secondary resonance frequency is still determined by Double resonance point network, therefore, the secondary resonance network is still in resonance.

(7) When the load modulation transistor 108 is turned on, the detuned capacitor 107 is connected to both ends of the inductor coil of the secondary resonant network 106, that is, in parallel with the double resonant point network. At this time, it is the detuned capacitor that determines the secondary resonant frequency. The total resonance network is formed in parallel with the double resonance point network. Therefore, the secondary resonance network is in a detuned state at this time.

(8) The secondary impedance change caused by the transition between the resonant state and the detuned state of the secondary resonant network will be mapped to the primary current. The primary side obtains the 2ASK modulation signal through the current detection module 104, and obtains the secondary side inverse response through the signal processing module 105. 2ASK digital baseband signal sent to.

To sum up, the primary side generates a 2FSK modulated signal through AC variable frequency drive according to the forward sending digital baseband signal and forms inductive energy coupling with the secondary side. The secondary side obtains the 2FSK modulated signal through current detection, and then passes through the phase-locked loop or single-frequency tuning circuit. Wait for signal processing to obtain the 2FSK digital baseband signal sent forward by the primary side. The secondary side uses the load power conversion circuit to provide the power required for the operation of the secondary side components. At the same time, the microprocessor obtains the 2ASK digital baseband signal sent in the reverse direction by the secondary side, and switches the load modulation detuning capacitor switch accordingly to form the secondary side. The conversion of the resonant network's resonant state and detuned state, and the resulting change in secondary side impedance will be mapped to the primary side current. The primary side obtains the 2ASK modulated signal through current detection, and after signal processing, the 2ASK digital baseband sent in the secondary side's reverse direction is obtained. signal, realizing the mixed transmission process of electric energy and full-duplex signals using the same inductive coupling channel in the ICPT system.

Claims (4)

1. A secondary circuit of an ICPT single-channel power and full-duplex signal hybrid transmission system, which is characterized by including: A double resonant point network, including a number of circuits composed of capacitors and inductors. The resonant frequencies are the two frequencies generated by the AC variable frequency drive module of the primary circuit, which is used to simultaneously tune the primary 2FSK modulated signal; the primary circuit includes: an AC variable frequency The drive module is used to generate a 2FSK modulation signal based on the forward-sending digital baseband signal obtained by the primary-side microprocessor; a resonant capacitor and an inductor coil are used to form the primary-side oscillation circuit; a current detection module is used to obtain the secondary-side The 2ASK modulated signal sent in the reverse direction by the circuit; a signal processing module used to obtain the digital baseband signal sent in the reverse direction by the secondary side circuit; A load power conversion module used to provide available power to the secondary components; A current detection module is used to obtain the 2FSK modulation signal sent forward by the primary circuit; A signal processing module used to obtain the 2FSK digital baseband signal sent forward by the primary circuit through a phase-locked loop or a single-frequency tuning circuit; A detuning capacitor is used in series with a load modulation transistor and then in parallel at both ends of the double resonant point network to selectively detun the secondary resonant network; A load modulation transistor is used to connect in series with the above-mentioned detuning capacitor and then in parallel at both ends of the dual resonance point network to selectively detun the secondary resonance network; A microprocessor and a load modulation module in digital baseband are used to generate a 2ASK digital baseband signal according to protocol requirements and selectively control the opening and closing of the load modulation transistor. 2. A method for mixed transmission of ICPT single-channel electric energy and full-duplex signals, which is characterized by adopting a full-duplex signal transmission method of forward 2FSK frequency modulation on the primary side and reverse 2ASK amplitude modulation on the secondary side; the primary-side circuit is based on The forward-sending digital baseband signal generates a 2FSK modulated signal through an AC variable frequency drive and forms inductive energy coupling with the secondary circuit as claimed in claim 1. The secondary circuit obtains the 2FSK modulated signal through current detection, and then obtains the forward-sent signal from the primary circuit. 2FSK digital baseband signal; the secondary side circuit uses the load power conversion circuit to provide the power required for the operation of the secondary side components. By turning on and off the load modulation transistor controlled by the digital baseband, it selectively builds on the original dual resonance point network. By changing the resonant frequency, the secondary resonant network is selectively in the detuned state and the resonant state, thereby obtaining different equivalent loads of the resonant network to achieve reverse 2ASK modulation of the load. The primary circuit obtains 2ASK modulation through current detection. After signal processing, the 2ASK digital baseband signal sent in the reverse direction by the secondary circuit is obtained; the dual resonance point network of the secondary circuit must have two resonance points, so that the reflected impedance change of the secondary circuit can be correctly reflected in the current of the primary circuit signal changes without being affected by the FM keying states 0 and 1 of the primary side, where: the primary side circuit includes: An AC variable frequency drive module is used to generate a 2FSK modulated signal based on the forward-sending digital baseband signal obtained by the primary-side microprocessor; A resonant capacitor and an inductor coil are used to form the primary oscillation circuit; A current detection module used to obtain the 2ASK modulated signal sent in the reverse direction by the secondary circuit; A signal processing module is used to obtain the digital baseband signal sent in the reverse direction by the secondary side circuit. 3. A method for mixed transmission of ICPT single-channel electric energy and full-duplex signals as claimed in claim 2, characterized in that the secondary circuit obtains the primary circuit through a phase-locked loop or a single-frequency tuning circuit. The 2FSK digital baseband signal sent in the forward direction of the circuit. 4. A method for mixed transmission of ICPT single-channel electric energy and full-duplex signals as claimed in claim 2, characterized in that it specifically includes the following steps: (1) The primary-side microprocessor of the primary-side circuit obtains a forward-sending digital baseband signal, and generates a 2FSK modulated signal through an AC variable frequency drive, which passes through the primary-side oscillation loop composed of the resonant capacitor of the primary-side circuit and the inductor coil of the primary-side circuit. , forming inductive energy coupling with the secondary circuit; (2) The secondary circuit uses the load power conversion module to provide the power required for normal operation of the secondary components; (3) The secondary circuit obtains the 2FSK modulated signal through current detection, and obtains the 2FSK digital baseband signal sent forward by the primary circuit; (4) After the microprocessor of the secondary circuit performs relevant processing on the signal to be transmitted back to the primary circuit and converts it into a digital quantity, the load modulation module in the digital baseband transmits it to the load modulation transistor according to the requirements of the protocol; (5) The load modulation transistor is in the corresponding on and off state according to the data transmitted from the load modulation module in the digital baseband; (6) When the load modulation transistor is turned off, the detuning capacitor is disconnected from both ends of the dual resonance point network, that is, it is not connected in parallel with the dual resonance point network. At this time, it is still the dual resonance point network that determines the secondary resonance frequency. Therefore, the secondary resonance network is still in resonance; (7) When the load modulation transistor is turned on, the detuned capacitor is connected to both ends of the inductor coil of the dual resonance point network, that is, in parallel with the dual resonance point network. At this time, it is the detuned capacitor and the dual resonance that determine the secondary resonance frequency. The total resonant network formed by the parallel connection of the point network, therefore, the secondary resonant network is in a detuned state at this time; (8) The secondary impedance change caused by the transition between the resonant state and the detuned state of the secondary resonant network will be mapped to the primary circuit current. The primary circuit obtains the 2ASK modulation signal through current detection, and the secondary circuit reverse direction is obtained through signal processing. The 2ASK digital baseband signal is sent.