Control device for applying universal controller to wireless charging system

Abstract

The utility model aims to provide a control device which can stably and reliably access a universal controller chip UCC28070A to a wireless charging system for application. The utility model comprises a main controller connected with the ground end of a wireless system, and a control parameter conversion module used for reading a digital signal sent by the main controller at the ground end of the wireless system, converting the digital signal into an analog quantity according to the size of a PWM duty ratio, and sending the analog quantity to a universal controller (U1); the current phase judgment circuit module is used for carrying out phase discrimination on two driving phase currents of the converter and then adjusting the phase of an output driving signal; the optocoupler isolation circuit module is used for electrically isolating the input side and the output side of driving signals of two driving phases of the converter; and the push-pull output circuit module is used for improving the driving capability and speed of two driving phases of the converter. The wireless charging device can be applied to the technical field of wireless charging.

Description

Technical Field

[0001] The utility model relates to the technical field of wireless charging, in particular to a control device applying a general controller to a wireless charging system. Background Art

[0002] The UCC28070A device, as an extended product of the UCC28070 series, is designed specifically to address the power factor correction (PFC) challenges in high-power application scenarios. This controller chip is optimized for PFC converters based on insulated gate bipolar transistors (IGBTs), enabling it to exhibit excellent performance even at low switching frequencies and making it suitable for PFC application fields such as air conditioners and white household appliances that widely adopt IGBT power switches.

[0003] The UCC28070A not only inherits the advantages of its basic model but also incorporates a series of innovative features to comprehensively improve the power factor (PF), efficiency, total harmonic distortion (THD), and transient response capabilities of the PFC system. Advanced technologies such as current synthesis and quantized voltage feedforward effectively drive the expansion of performance boundaries. In addition, the integrated frequency jitter control, clock synchronization mechanism, and slew rate enhancement function further unlock the potential for performance improvement, ensuring the system operates efficiently and stably under diverse operating conditions.

[0004] Although the UCC28070A, as a general controller chip, has wide applicability and powerful functionality, it is not designed to meet the customized requirements of all specific application scenarios. Such controller chips, like the UCC28070A, are intended to provide standardized solutions for specific functions such as power factor correction controllers or LLC resonant converters to cover the common needs of various application environments, rather than focusing on the personalized configuration of a particular customer or application. Despite its professional orientation, its design intention is not limited to individual projects but is targeted at a broad market user group.

[0005] Taking a wireless charging system as an example, the ground end (transmitting end) usually requires a front-end PFC converter to improve the power factor of the entire power system, achieve efficient utilization of power resources, reduce the burden on the power grid, save energy and reduce emissions, and reduce electromagnetic interference to the power grid. However, compared with conventional PFC technical solutions, certain specific wireless charging architectures, such as the buck + inverter combination, pose more unique requirements for the ground-end PFC: even when the target voltage setting instruction has not been received, the PFC should have the ability to start autonomously and execute output control. This special requirement stems from the inherent structural characteristics of the wireless charging system, that is, the output end feedback is physically isolated from the ground end, and it is required that the PFC flexibly adapts to the wireless transmission algorithm and dynamically adjusts the output parameters to meet the system specificity. Obviously, these complex operations go beyond the scope of the standard usage of general controller chips, and the commonly provided chip usage examples often do not cover the application guidance for such special systems.

[0006] In addition, during the debugging or standby phase of the wireless charging system, it is required that the ground-end PFC component has the pre-activation ability. When the vehicle-side coil has not approached yet, the ground-end converter needs to start first to build an electromagnetic field to detect the degree of mutual inductance, which requires the front-end PFC to enter the normal working state in advance to prepare for subsequent wireless energy transmission.

[0007] Considering the possible long development cycle and high cost brought by adopting a fully digital PFC solution such as DSP for the PFC technical solution required for the wireless charging system, the value of general controller chips such as UCC28070A is particularly prominent. Although it cannot directly meet all special application requirements, due to its advantages of high efficiency, stability and economy, such chips become an ideal choice for quickly building a high-performance wireless charging PFC system while taking into account development efficiency and cost control.

[0008] As a general controller chip, the design and functional characteristics of UCC28070A are mainly aimed at power system applications with traditional wired connections and physical contact between the feedback point and the PFC body. Such chips usually assume in their structure and algorithm that the feedback signal can be transmitted to the controller in real time and accurately through a direct physical interface for immediate adjustment. Therefore, when facing an application scenario such as a wireless charging system, which is highly atypical and has no physical contact in the feedback path, the normal technical application method of UCC28070A does have limitations.

[0009] First, the core feature of a wireless charging system is that the energy transfer between the transmitter and the receiver is accomplished through electromagnetic field coupling rather than traditional wire connections. This means that the communication and control between the PFC (Power Factor Correction) unit and other parts of the system (such as the feedback circuit) must be achieved wirelessly. However, as a general-purpose controller, the built-in control logic and modulation method of UCC28070A are designed for wired feedback environments and are difficult to adapt to the signal transmission delay, interference, and non-linear characteristics in a wireless environment. As a result, it cannot freely control output parameters such as output voltage and output current. These parameters are often preset and fixed in general-purpose chips or allow limited external adjustment, but do not have the ability to be deeply customized for the specific requirements of wireless charging systems.

[0010] Second, in some operating modes of the wireless charging system (such as debugging or standby states), the PFC component is required to have a pre-activation ability, that is, it can start and maintain a basic operating state even when no clear feedback signal or target setting value is received. This feature is crucial for exploring the mutual inductance, establishing the initial magnetic field, and preparing for subsequent energy transfer. However, the triggering and maintenance of the operating state of general-purpose controller chips such as UCC28070A highly depend on real-time physical contact feedback information. In a wireless environment lacking such feedback, the chip cannot determine by itself when and how to perform a pre-power-on operation, which is contrary to the operating requirements of the wireless charging system.

[0011] In summary, although UCC28070A, as a general-purpose controller chip, demonstrates excellent performance and flexibility in many traditional power applications, in application scenarios such as wireless charging systems where the feedback mechanism and operating mode are significantly different, its normal technical application method is indeed difficult to meet specific requirements such as freely controlling output parameters and pre-power-on. Solving these problems may require a customized controller chip specifically designed for wireless charging systems, or the adoption of additional hardware and software solutions to bridge the functional gap between general-purpose chips and the wireless charging application environment. Summary of the Invention

[0012] The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a control device that can stably and reliably connect the general-purpose controller chip UCC28070A to a wireless charging system for application.

[0013] The technical solution adopted by the present invention is that the control device constructs a converter topology based on a general-purpose controller of model UCC28070A. The interleaved phase difference between the A drive phase and the B drive phase of the converter is 180°, and the current conduction mode is the CCM mode. The communication controller of the converter is communicatively connected to the main controller of the ground terminal of the wireless charging system. The control device includes

[0014] A main controller connected to the ground terminal of the wireless system, which is used to read the digital signal sent by the main controller of the ground terminal of the wireless system and convert it into an analog quantity according to the PWM duty cycle size for the control parameter conversion module of the general controller;

[0015] A current phase judgment circuit module used to detect the phase of the two drive phase currents of the converter and then adjust the phase of the output drive signal;

[0016] An optocoupler isolation circuit module used to electrically isolate the input side and output side of the drive signals of the two drive phases of the converter; and

[0017] A push-pull output circuit module used to improve the drive ability and speed of the two drive phases of the converter.

[0018] As can be seen from the above solution,

[0019] Further, the control parameter conversion module consists of an integrator and a voltage follower. The PWM signal output by the PWM of the main controller of the ground terminal of the wireless system is accessed from the PWMA pin. The control parameter conversion module outputs an AC voltage analog signal to the general controller from the VINAC pin, outputs a voltage feedback analog signal to the general controller from the VSEN_FB pin, and accesses the circuit stop enable signal from the VSEN pin.

[0020] Furthermore, the CSA / CSB pins of the current phase judgment circuit module receive the detection inputs of the A / B phase currents. During the conduction time of the GDB pin, the CSB pin is connected to the inverting input terminal of the A / B phase current amplifier through the current synthesis stage.

[0021] In addition, the optocoupler isolation circuit module isolates and outputs the A / B phase gate drive signals of the converter to the PFC module of the ground terminal of the wireless charging system through the set isolation device.

[0022] More specifically, the PWMDRVA / PWMDRVB pins of the push-pull output circuit module access the A / B phase gate drive isolation signals, and the BOOSTGATE1 / BOOSTGATE2 pins access the A / B phase gate drive signals.

[0023] The beneficial effects of the present utility model are:

[0024] 1. The present utility model generates a conversion circuit through the input AC voltage analog signal (VINAC) and the output voltage feedback analog signal (VSEN_FB), enabling the general controller chip UCC28070A to adapt to the contactless feedback mechanism of the wireless charging system and achieve precise control of the PFC unit;

[0025] 2. By introducing the input voltage and output voltage analog signals, the utility model breaks the limitation of the general controller chip on the preset fixed or limited adjustment of output parameters, endows the UCC28070A with the ability to freely control the output voltage and current in wireless charging applications, and significantly improves the dynamic response and steady-state performance of the system;

[0026] 3. Aiming at the pre-activation requirement of the PFC component in the wireless charging system, the utility model enables the UCC28070A to start and maintain the basic working state without receiving a clear feedback signal through various circuit modules, ensuring that the wireless charging system can smoothly establish the mutual inductance and initialize the magnetic field during debugging and standby states, and making preparations for subsequent energy transmission;

[0027] 4. The utility model adopts a current phase judgment circuit, optocoupler isolation technology and a push-pull output structure, enhances the precise control of the UCC28070A over the A / B phase current, effectively suppresses the signal interference in the wireless environment, improves the stability and response speed of the drive signal, and enhances the anti-interference ability and safety of the system;

[0028] 5. By specifically expanding and optimizing the general controller chip UCC28070A, the utility model successfully solves its limitations in wireless charging applications, realizes innovative applications based on the existing mature hardware, reduces the system cost, shortens the product listing time, and has significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is the simplified circuit schematic diagram of the control parameter transformation module;

[0030] Figure 2 is the simplified circuit schematic diagram of the circuit module with 2UCC28070A as the core;

[0031] Figure 3 is the simplified circuit schematic diagram of the current phase judgment circuit module;

[0032] Figure 4 is the simplified circuit schematic diagram of the optocoupler isolation circuit module;

[0033] Figure 5 is the simplified circuit schematic diagram of the push-pull output circuit module;

[0034] Figure 6 is the simplified circuit schematic diagram of the PFC module at the ground end of the wireless charging system. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0035] As Figures 1 to 6As shown, the utility model constructs a converter topology based on a general controller U1 of model UCC28070A. The interleaved phase difference between the A drive phase and the B drive phase of the converter is 180°. The current conduction mode is the CCM mode (continuous conduction mode). The communication controller of the converter is communicatively connected to the main controller at the ground end of the wireless charging system. The control device includes

[0036] A main controller connected to the ground end of the wireless system, configured to read a digital signal sent by the main controller at the ground end of the wireless system, and convert it into an analog quantity according to the PWM duty cycle size for the control parameter conversion module of the general controller U1;

[0037] A current phase judgment circuit module configured to perform phase discrimination on the currents of the two drive phases of the converter, and then adjust the phase of the output drive signal;

[0038] An opto-isolation circuit module configured to electrically isolate the input side and the output side of the drive signals of the two drive phases of the converter; and

[0039] A push-pull output circuit module configured to enhance the drive capability and speed of the two drive phases of the converter.

[0040] Next, a specific introduction to the utility model will be given.

[0041] An interleaved continuous conduction mode PFC is implemented through a general controller chip UCC28070A. The converter can take into account debugging and controllable function application technologies. After applying the PFC calculation scheme of the utility model in the wireless system, the PFC constructed by UCC28070A can be incorporated into the control algorithm for more detailed and extended applications. That is to say, the main controller of the wireless system can operate the working process of the general controller chip UCC28070A. The converter topology type constructed by UCC28070A in the utility model is an interleaved continuous conduction mode boots PFC. The interleaved phase difference between the two drive waveforms of this type of converter is 180°, and the current conduction mode is the CCM mode (continuous conduction mode).

[0042] As Figure 1 shown is the circuit module connecting to the PWM output port of the main controller at the ground end of the wireless system. The function of this circuit module is to read the digital signal sent by the main controller at the ground end of the wireless system, and convert it into a relevant analog quantity according to the PWM duty cycle size. This circuit is mainly composed of an integrator U3-B and a voltage follower U3-A to form the structure as shown. The definitions of each pin are as follows.

[0043] 1) PWMA: PWM output of the main controller at the ground end of the wireless system. This represents a control quantity, the value of which is output by the control strategy and operation algorithm of the wireless charging system itself.

[0044] 2) VSEN: Enable signal. It can be provided by some protection circuits or other protection mechanisms. Stop the operation of this circuit when a fault occurs in the system.

[0045] 3) VINAC: Quasi-input AC voltage analog signal. It is used to simulate an input AC voltage information and is provided to UCC28070A for operation.

[0046] 4) VSEN_FB: Quasi-output voltage analog signal. It is used to simulate an output voltage feedback information and is provided to UCC28070A for operation.

[0047] U3: Operational amplifier. This is a dual operational amplifier package, so it is divided into A and B, that is, there are two operational amplifier circuits in the same package. In this module, U3-B constructs an integrator, and U3-A constructs a voltage follower.

[0048] As Figure 2 shown is the circuit module with UCC28070A as the core. The function of this circuit module is to enable UCC28070A to receive Figure 1 two quasi-signals (VINAC and VSEN_FB) for normal operation as a general controller chip. U1 is UCC28070A. The names of each pin above do not belong to the scope of this utility model, and its connection method is similar to the general solution. Here, only this special application method of the general controller chip UCC28070A is shown. The definitions of each pin are as follows.

[0049] 1) VINAC: Quasi-input AC voltage analog signal. It is used to simulate an input AC voltage information and is internally connected to the negative pole of the multiplier and the current synthesis differential amplifier in UCC28070A.

[0050] 2) VSEN_FB: Quasi-output voltage analog signal. It is used to simulate an output voltage feedback information and is internally connected to the inverting input of the transconductance voltage error amplifier and the positive pole of the current synthesis differential amplifier in UCC28070A.

[0051] 3) CSA / CSB: A / B phase current detection input. During the conduction time of GDB, CSB is connected to the inverting input of the A / B phase current amplifier through the current synthesis stage.

[0052] 4) GDA / GDB: A / B phase gate drive signal.

[0053] 5) +12_PFC: 12V power supply for the auxiliary power system of PFC.

[0054] As Figure 3 shown, it is the current phase judgment circuit module. A circuit used to detect the phase of the phase current and then adjust the phase of the output drive signal. The definitions of each pin are as follows.

[0055] 1) CSA / CSB: A / B phase current detection input. During the conduction time of GDB, CSB is connected to the inverting input terminal of the A / B phase current amplifier through the current synthesis stage.

[0056] 2) GDA / GDB: A / B phase gate drive signal.

[0057] 3) +12_PFC: 12V power supply for the auxiliary power system of PFC.

[0058] As Figure 4 shown, it is the opto-isolation circuit module of the A / B phase gate drive signal. This process of opto-electronic conversion and optical transmission realizes the electrical isolation between the input side and the output side. The definitions of each pin are as follows.

[0059] 1) GDA / GDB: A / B phase gate drive signal.

[0060] 2) PWMDRVA / PWMDRVB: A / B phase gate drive isolation signal.

[0061] 3) +12_PFC: 12V power supply for the auxiliary power system of PFC.

[0062] 4) GND: Ground.

[0063] As Figure 5 shown is the push-pull output circuit module of the A / B phase gate drive. The drive ability and response speed are improved through push-pull output. The definitions of each pin are as follows.

[0064] PWMDRVA / PWMDRVB: A / B phase gate drive isolation signal.

[0065] BOOSTGATE1 / BOOSTGATE2: A / B phase gate drive.

[0066] +12_PFC: 12V power supply for the auxiliary power system of PFC.

[0067] GND: Ground.

[0068] As Figure 6 shown is the circuit diagram of the main power loop of this interleaved continuous conduction mode boots PFC converter. Its topology type is interleaved boots PFC, and the interleaved phase of phase A and phase B is 180°.

[0069] 1) CSA / CSB: A / B phase current detection input.

[0070] 2) BOOSTGATE1 / BOOSTGATE2: A / B phase gate drive.

[0071] 3) AC-INPUT: AC input sampling port.

[0072] 4) OUTPUT: Converter output.

[0073] The utility model has the following advantages and effects:

[0074] By adding specific signal conversion modules and control algorithms, the utility model overcomes the dependence of general controller chips on physical contact feedback, enabling it to adapt to the electromagnetic field coupling energy transmission mode in wireless charging systems. By simulating the input AC voltage (VINAC) and output voltage feedback (VSEN_FB) signals, the utility model successfully realizes the effective communication between UCC28070A and the wireless charging system, ensuring the precise control of the PFC unit by the controller in a wireless environment.

[0075] Different from traditional general controller chips that preset fixed or only allow limited adjustment of output parameters, the utility model endows UCC28070A with the ability to freely control output voltage and current in wireless charging applications by introducing quasi-input voltage and output voltage analog signals. This deeply customized control strategy enables the PFC to flexibly respond to various load changes and interference effects in complex and non-linear wireless environments, significantly improving the dynamic response and steady-state performance of the system.

[0076] To meet the requirement that the PFC component in the wireless charging system needs to have a pre-activation ability, the utility model designs a special control logic and circuit module, enabling UCC28070A to start and maintain a basic working state without receiving a clear feedback signal. This innovation solves the problem that general controller chips cannot autonomously judge the pre-power-on timing in a wireless environment, ensuring that the wireless charging system can successfully establish mutual inductance and initialize the magnetic field during debugging and standby states, making full preparations for subsequent energy transmission.

[0077] By introducing a current phase judgment circuit, optocoupler isolation technology, and a push-pull output structure, the utility model strengthens the precise control of UCC28070A over the A / B phase current, effectively suppressing signal interference in the wireless environment, and improving the stability and response speed of the drive signal. At the same time, optocoupler isolation provides electrical isolation protection, enhancing the safety and anti-interference ability of the system. These improvements significantly enhance the overall stability and reliability of the wireless charging system.

[0078] The utility model cleverly uses the general controller chip UCC28070A as the core, and through additional circuit modules and control algorithms, it has carried out targeted expansion and optimization on it, enabling the controller that was originally not applicable to the wireless charging system to be efficiently utilized. This design avoids the development cost and research and development cycle of developing a completely new customized digital converter, realizes innovative applications based on existing mature hardware, is beneficial to reducing system costs, shortening the product listing time, and has significant economic benefits.

[0079] Finally, it should be emphasized that the above are only the preferred embodiments of the utility model and are not used to limit the utility model. For those skilled in the art, the utility model can have various changes and modifications. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the utility model shall be included within the protection scope of the utility model.

Claims

1. A control device using a universal controller in a wireless charging system, characterized in that: The control device builds a converter topology based on a universal controller (U1) of model UCC28070A. The interlaced phase difference between the A drive phase and the B drive phase of the converter is 180°, and the current conduction mode is CCM mode. The communication controller of the converter is connected to the main controller of the wireless charging system ground end. The control device includes A main controller connected to the ground end of the wireless system is used to read the digital signal sent by the main controller of the ground end of the wireless system and convert it into an analog quantity according to the PWM duty cycle to a control parameter conversion module of the universal controller (U1); A current phase determination circuit module for performing phase discrimination on two driving phase currents of the converter and then adjusting the phase of the output driving signal; An optocoupler isolation circuit module for electrically isolating the input side and the output side of the drive signals of the two drive phases of the converter; as well as A push-pull output circuit module for improving the driving capability and speed of the two driving phases of the converter; The control parameter conversion module receives a PWM signal outputted by the PWM of the main controller at the ground end of the wireless system from the PWMA pin, outputs an AC voltage analog signal to the universal controller (U1) from the VINAC pin, outputs a voltage feedback analog signal to the universal controller (U1) from the VSEN_FB pin, and receives a circuit stop enable signal from the VSEN pin; The CSA / CSB pin of the current phase judgment circuit module receives the detection input of the A / B phase current, and during the conduction time of the GDB pin, the CSB pin is connected to the inverting input terminal of the A / B phase current amplifier through the current synthesis stage; The optical coupling isolation circuit module isolates the A / B phase gate drive signal of the converter through the provided isolation device (U106) and outputs it to the PFC module at the ground end of the wireless charging system; The PWMDRVA / PWMDRVB pins of the push-pull output circuit module are connected to the A / B phase gate drive isolation signal, and the BOOSTGATE1 / BOOSTGATE2 pins are connected to the A / B phase gate drive signal.

2. A control device for applying a universal controller to a wireless charging system according to claim 1, characterized in that: The control parameter conversion module is composed of an integrator (U3-B) and a voltage follower (U3-A).

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