Power supply circuit and DC-DC converter

Abstract

The invention relates to a power supply circuit and a DC-DC converter. The filtering module is used for filtering the high-frequency signal according to an input signal of a power supply bus of the power supply circuit to obtain a filtered signal; the modulation circuit is used for adjusting the voltage difference between the initial output voltage and the reference voltage of the power supply circuit according to the intermediate frequency signal representing the metadata and the high frequency signal representing the communication data segment to obtain a communication signal representing the communication data segment; the frequency of the intermediate-frequency signal is higher than that of the high-frequency signal; the flyback transformer module is used for adjusting the filtered signal according to the time when the communication signal is conducted, and transforming the adjusted filtered signal to obtain a target output voltage of the power supply circuit; the target output voltage is used for performing power supply and communication on the DC-DC converter; the initial output voltage is an output voltage generated prior to the target output voltage. According to the invention, the power transmission line can be reused, and communication can be ensured while normal power supply is realized.

Description

Technical Field

[0001] This application relates to the field of power communication, and in particular to a power supply circuit and a DC-DC converter. Background Technology

[0002] As the proportion of renewable energy in the power system continues to increase, the phenomenon of power curtailment caused by the lack of large-scale grid connection of new energy sources is becoming increasingly prominent.

[0003] Based on this, intelligent energy coordination management of DC microgrids has gradually become an important development direction for the efficient utilization of new energy sources, which poses new challenges to the system's information interaction architecture and dynamic control capabilities. Common communication methods for DC microgrids include wireless communication. However, wireless communication is limited by complex application scenarios and suffers from issues related to communication distance, security, and quality. Summary of the Invention

[0004] Therefore, it is necessary to provide a power supply circuit and a DC-DC converter to solve the problem of limited communication in complex environments and over long distances for DC microgrids.

[0005] This application provides a power supply circuit, which includes a filter module, a modulation circuit, and a flyback transformer module;

[0006] The filtering module is used to filter out high-frequency signals based on the input signal of the power supply bus of the power supply circuit to obtain a filtered signal.

[0007] The modulation circuit is used to adjust the voltage difference between the initial output voltage and the reference voltage of the power supply circuit based on the intermediate frequency signal representing metadata and the high frequency signal representing a communication data segment, so as to obtain a communication signal representing the communication data segment; the frequency of the intermediate frequency signal is higher than the frequency of the high frequency signal.

[0008] The flyback transformer module is used to adjust the filtered signal according to the timing of the communication signal being turned on, and to transform the adjusted filtered signal to obtain the target output voltage of the power supply circuit; the target output voltage is used to power the DC-DC converter for communication; the initial output voltage is the output voltage generated before the target output voltage.

[0009] In one embodiment, the flyback transformer module includes the high-frequency transformer and a power switch; the input terminal of the high-frequency transformer is connected to the filter module, the filter module is connected to the positive terminal of the power supply bus, the output terminal of the high-frequency transformer is connected to the drain of the power switch, the source of the power switch is connected to the negative terminal of the power supply bus, the gate of the power switch is connected to the modulation circuit, and the gate of the power switch is used to receive the communication signal.

[0010] In one embodiment, the filtering module includes a filtering inductor and an input filtering capacitor. The filtering inductor is connected between the positive terminal of the power supply bus and the positive terminal of the input filtering capacitor, and the negative terminal of the input filtering capacitor is connected to the negative terminal of the power supply bus. The input terminal of the flyback transformer module is connected to the positive terminal of the input filtering capacitor. The frequency of the high-frequency signal is negatively correlated with the product of the filtering inductor and the input filtering capacitor.

[0011] In one embodiment, the flyback transformer module further includes a power diode and an output filter capacitor; the positive terminal of the power diode is connected to the output outlet of the high-frequency transformer, the negative terminal of the power diode is connected to the positive terminal of the output filter capacitor, and the negative terminal of the power diode is connected to the output positive terminal of the flyback transformer module; the negative terminal of the output filter capacitor is connected to the output negative terminal of the flyback transformer module and the output inlet of the high-frequency transformer.

[0012] In one embodiment, the modulation circuit includes:

[0013] A first feedback control circuit is connected to a reference voltage and the initial output voltage of the power supply circuit. The first feedback control circuit is used to determine the voltage difference between the reference voltage and the initial output voltage of the power supply circuit, and to generate a first action signal based on the voltage difference between the reference voltage and the initial output voltage of the power supply circuit.

[0014] The second feedback control circuit is connected to the first action signal, the input signal of the power supply bus, and the intermediate frequency signal representing metadata. The second feedback control circuit is used to determine the addition result between the action signal and the intermediate frequency signal, and the signal difference between the addition result and the input signal, and generate a second action signal based on the signal difference between the addition result and the input signal.

[0015] A communication arithmetic unit, wherein the communication arithmetic unit receives the second action signal and the high-frequency signal representing the communication data segment; the communication arithmetic unit is used to calculate the difference between the second action signal and the high-frequency signal to obtain a control signal;

[0016] A thresholder is provided, wherein the threshold determiner receives the control signal and generates the communication signal based on the comparison result between the control signal and the threshold.

[0017] In one embodiment, the metadata is used to generate an intermediate frequency (IF) baseband signal and an inverse IF baseband signal with opposite bits, the sum of the product of the IF baseband signal and a first IF carrier, and the product of the inverse IF baseband signal and a second IF carrier, which is the IF signal.

[0018] In one embodiment, the communication data is used to generate a high-frequency baseband signal, the sum of the product of the high-frequency baseband signal and the triangular carrier, and the product of the high-frequency baseband inverse signal and the corresponding inverse triangular carrier is the high-frequency signal.

[0019] In one embodiment, the frequency of the triangular carrier wave is adapted to the frequency of the power switch used to turn on the communication signal.

[0020] In one embodiment, the power supply circuit further includes a demodulation circuit, which includes a high-frequency filter circuit and different intermediate-frequency filter circuits respectively connected to the input signals of the power supply bus.

[0021] The different intermediate frequency (IF) filtering circuits are used to bandpass filter the input signal of the power supply bus into different bandpass filtered signals according to the center frequency and frequency band corresponding to different IF carriers; scale the amplitude of the different bandpass filtered signals into different scaled signals according to a scaling factor; perform low-pass filtering based on the values ​​of the different scaled signals to obtain different low-pass filtered signals; compare the different low-pass filtered signals with a decoding threshold to obtain different threshold determination results; and perform subtraction on the different threshold determination results to obtain the IF analog signal to be processed representing metadata.

[0022] A high-frequency filtering circuit is used to: bandpass filter the input signal of the power supply bus into a bandpass filtered signal corresponding to the high-frequency filtering circuit, according to the frequency band corresponding to the high-frequency filtering circuit; scale the amplitude of the high-frequency bandpass filtered signal into a scaled signal of the high-frequency filtering circuit according to a high-frequency scaling factor; inject the scaled high-frequency signal into a triangular signal carrier to obtain a fused signal; perform low-pass filtering on the fused signal to obtain a low-pass filtered signal of the high-frequency filtering circuit; and compare the low-pass filtered signal of the high-frequency filtering circuit with a decoding threshold to obtain a high-frequency analog signal to be processed representing a communication data segment.

[0023] The signal processing module is used to receive the intermediate frequency analog signal to be processed and the high frequency analog signal to be processed; to perform sampling and decision processing on the intermediate frequency analog signal to be processed and the high frequency analog signal to be processed respectively to obtain the intermediate frequency baseband signal to be processed and the high frequency baseband signal to be processed; and to restore the intermediate frequency baseband signal to be processed and the high frequency baseband signal to be processed into a data frame.

[0024] This application also provides a DC-DC converter for powering a DC microgrid. One end of the DC-DC converter is connected to the input signal of the power supply bus, and the other end of the DC-DC converter is connected to a distributed load. The power supply of the DC-DC converter includes the power supply circuit described in any of the above embodiments.

[0025] In the aforementioned power supply circuit and DC-DC converter, the filtering module removes high-frequency signals from the input signal, obtaining a filtered signal. This reduces the impact of the input signal on the modulation circuit, facilitating the introduction of input current feedback through the modulation circuit containing a power control loop, indirectly achieving the amplification effect of the communication signal. The modulation circuit enables the power supply circuit to have communication functionality. With the assistance of the modulation circuit, the transmission line can be reused, ensuring communication while providing normal power supply, without the need for additional communication auxiliary equipment. It only requires modification of the control mode of the existing auxiliary power supply, significantly reducing communication costs. The intermediate frequency (IF) signal is based on the IF carrier of the power supply circuit, while the high-frequency signal is based on the high-frequency carrier of the power supply circuit. The IF carrier has strong amplitude adjustability but a slow communication rate; the high-frequency carrier has poor amplitude adjustability but a high communication rate. Using both frequencies allows for data frame splitting, improving the communication rate. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 One embodiment of a power supply circuit is a modular structure;

[0028] Figure 2 for Figure 1 A specific module structure of a flyback transformer module;

[0029] Figure 3 for Figure 1 A modular structure for modulation circuits;

[0030] Figure 4 for Figure 1 A modular structure for demodulation circuits;

[0031] Figure 5 This is a schematic diagram illustrating the application scenarios of a DC-DC converter.

[0032] Explanation of reference numerals in the attached figures:

[0033] 100 - Filter module; 200 - Modulation circuit; 300 - Flyback transformer module. Detailed Implementation

[0034] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0035] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0036] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0037] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0038] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0039] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0040] like Figure 1As shown, a power supply circuit in one embodiment includes a filtering module 100, a modulation circuit 200, and a flyback transformer module 300. The filtering module 100 is used to filter out high-frequency signals based on the input signal of the power supply bus of the power supply circuit to obtain a filtered signal. The modulation circuit 200 is used to adjust the voltage difference between the initial output voltage and the reference voltage of the power supply circuit based on the intermediate frequency signal representing metadata and the high-frequency signal representing communication data segments to obtain a communication signal representing the communication data segments. The frequency of the intermediate frequency signal is higher than the frequency of the high-frequency signal. The flyback transformer module 300 is used to adjust the filtered signal based on the timing of the communication signal conduction and to transform the adjusted filtered signal to obtain the target output voltage of the power supply circuit. The target output voltage is used to power the DC-DC converter for communication. The initial output voltage is the output voltage generated before the target output voltage.

[0041] The input signal to the power supply bus is the current or voltage input to the power circuit via a DC converter. A DC microgrid includes multiple DC-DC converters, one end of which is connected to the DC bus, and the other end is connected to distributed loads; distributed loads include distributed resources such as photovoltaic systems, charging piles, and power batteries.

[0042] The filter module 100 is used to filter out high-frequency signals from the input signal of the power supply circuit, thereby reducing the impact of the input signal on the modulation circuit 200. This facilitates the introduction of input current feedback through the modulation circuit 200, which contains a power control loop, indirectly achieving the amplification effect of the communication signal. The filtered signal is the voltage or current from the input signal after removing the high-frequency signal.

[0043] The modulation circuit 200 is used to enable the power supply circuit to have communication functionality. With the assistance of the modulation circuit 200, the transmission line can be reused, ensuring communication while supplying power normally, without the need for additional communication auxiliary equipment. It can be achieved simply by modifying the control mode of the original auxiliary power supply, which greatly reduces communication costs.

[0044] Metadata is data unrelated to the data itself, including but not limited to frame headers, address codes, frame trailers, and checksums that aid communication. Communication data segments represent the content of the data segment to be sent, and their specific meaning can be characterized through these segments. Intermediate frequency (IF) signals are signals based on an IF carrier within a power supply circuit, while high-frequency (HF) signals are signals based on a HF carrier within a power supply circuit. IF carriers have strong amplitude adjustability but slow communication rates; HF carriers have poor amplitude adjustability but high communication rates. Using both frequencies together allows for data frame splitting, improving communication speed. The HF carrier can be a triangular carrier.

[0045] The reference voltage is the output voltage command, representing the desired output voltage value indicated by the command. The initial output voltage is the actual output voltage, and it can be the output voltage at the moment before the target output voltage is obtained. The voltage difference between the reference voltage and the initial voltage needs to be adjusted to establish the foundation for power supply. Based on this, adjustments can be made according to the intermediate frequency signal and the high frequency signal to form a communication signal, enabling the power supply to not only provide power but also have communication capabilities.

[0046] The flyback transformer module 300 includes a switching element, an input terminal of the winding, and an output terminal. When the switching element is turned on, the input signal enters the transformer input terminal and stores energy in the transformer's magnetic field. When the switching element is turned off, the input signal flow stops, the transformer's magnetic field begins to contract, and the flyback transformer module generates a corresponding voltage at the output terminal, thus obtaining the output voltage of the flyback transformer module. Its function is to reduce the high voltage of the DC bus to the low voltage required by the power supply circuit.

[0047] The target output voltage of the power supply circuit is the voltage used for power supply and communication at the current moment. The moment when the output voltage of the power supply circuit is the initial output voltage precedes the moment when the output voltage of the power supply circuit reaches the target output voltage.

[0048] In one embodiment, the filter module 100 is connected to the power supply bus of the power supply circuit to obtain the input signal; the input terminal of the modulation circuit 200 is connected to the communication control terminal, the output terminal of the modulation circuit 200 is connected to the input terminal of the flyback transformer module 300, and the input terminal of the flyback transformer module 300 is connected to the power supply bus.

[0049] In this embodiment, the filtering module 100 filters out the high-frequency signal of the input signal to obtain a filtered signal, thereby reducing the impact of the input signal on the modulation circuit 200. This facilitates the introduction of input current feedback through the modulation circuit 200, which contains a power control loop, indirectly achieving the amplification effect of the communication signal. The modulation circuit 200 is used to enable the power supply circuit to have communication functionality. With the assistance of the modulation circuit 200, the transmission line can be reused, ensuring communication while providing normal power supply, without the need for additional communication auxiliary equipment. It can be achieved simply by modifying the control mode of the original auxiliary power supply, significantly reducing communication costs. The intermediate frequency signal is a signal based on the intermediate frequency carrier of the power supply circuit, and the high-frequency signal is a signal based on the high-frequency carrier of the power supply circuit. The intermediate frequency carrier has a strong adjustable amplitude but a slow communication rate; the high-frequency carrier has a poor adjustable amplitude but a high communication rate. By using both frequencies, data frames are split, improving the communication rate.

[0050] In one embodiment, the flyback transformer module 300 includes a high-frequency transformer and a power switch; the input terminal of the high-frequency transformer is connected to the filter module 100, the filter module 100 is connected to the positive terminal of the power supply bus, the output terminal of the high-frequency transformer is connected to the drain of the power switch, the source of the power switch is connected to the negative terminal of the power supply bus, the gate of the power switch is connected to the modulation circuit 200, and the gate of the power switch is used to receive communication signals.

[0051] When the power switch is turned on, the input terminal of the high-frequency transformer is the current inflow port of the primary winding, and the input terminal of the high-frequency transformer is the current outflow port of the primary winding. Correspondingly, the output terminal of the high-frequency transformer is the port where the secondary winding outputs its voltage. The positive terminal of the power supply bus indicates the direction in which current flows into the power circuit.

[0052] In this embodiment, the communication signal acts on the gate, making the communication signal a driving signal. The communication signal controls the conduction time of the power switch, thereby realizing communication. The source is connected to the negative terminal of the power supply bus, making the driving signal of the power switch relatively stable.

[0053] In some embodiments, the filtering module 100 includes a filtering inductor and an input filtering capacitor. The filtering inductor is connected between the positive terminal of the power supply bus and the positive terminal of the input filtering capacitor, and the negative terminal of the input filtering capacitor is connected to the negative terminal of the power supply bus. The input terminal of the flyback transformer module 300 is connected to the positive terminal of the input filtering capacitor. The frequency of the high-frequency signal is negatively correlated with the product of the filtering inductor and the input filtering capacitor.

[0054] In one exemplary embodiment, the frequency of the high-frequency signal can be obtained by multiplying the square root of the product of the filter inductance and the input filter capacitor by 2π.

[0055] In this embodiment, an LC filter circuit is formed by combining a filter inductor and an input filter capacitor. In this case, the product of the filter inductor and the input filter capacitor is negatively correlated with the frequency of the high-frequency signal, so that the transmission efficiency is adapted to the circuit structure, thereby ensuring the communication effect.

[0056] In some embodiments, the flyback transformer module 300 further includes a power diode and an output filter capacitor; the positive terminal of the power diode is connected to the output terminal of the high-frequency transformer, the negative terminal of the power diode is connected to the positive terminal of the output filter capacitor, and the negative terminal of the power diode is connected to the output positive terminal of the flyback transformer module 300; the negative terminal of the output filter capacitor is connected to the output negative terminal of the flyback transformer module 300 and the output terminal of the high-frequency transformer.

[0057] The output terminal of the high-frequency transformer is the current outlet port of the secondary winding when the power switch is turned off. The output terminal of the high-frequency transformer is the current inlet port of the secondary winding when the power switch is turned off. This forms a flyback voltage control. The voltage between the positive and negative output terminals of the flyback transformer module 300 is the output voltage of the flyback transformer module 300.

[0058] In this embodiment, when the power switch is turned on, the power diode is reverse-biased to prevent energy backflow or short circuit, and the voltage released by the output filter capacitor ensures a relatively stable output voltage; when the power switch is turned off, the power diode is forward-biased and powered by the high-voltage frequency converter.

[0059] In one exemplary embodiment, such as Figure 2 As shown, the power supply circuit provides auxiliary power to the DC-DC converter, and includes an LC filter module and a single-stage flyback transformer module 300; the LC filter module includes a filter inductor. Input filter capacitor Its function is to filter out high-frequency signals from the input current, so that input current feedback can be introduced into the power control loop. Input filter inductor One end is connected to the positive terminal of the DC bus, and the other end is connected to the positive terminal of the filter inductor. The positive terminal of the filter capacitor is connected to one end of the filter inductor, and the negative terminal is connected to the negative terminal of the DC bus. The single-stage flyback transformer module 300 includes a high-frequency transformer T, a power switch S1, a power diode D1, and an output filter capacitor C2. Its function is to reduce the high voltage of the DC bus to the low voltage required by the auxiliary power supply. The high-frequency transformer T has an input terminal connected to the positive terminal of the filter capacitor, an input terminal connected to the drain of the power switch S1, an output terminal connected to the positive terminal of the power diode D1, and an output terminal connected to the negative terminal of the output filter capacitor. The drain of the power switch S1 is connected to the input terminal of the high-frequency transformer T, and its source is connected to the negative terminal of the DC bus. The gate of the power switch S1 is connected to the modulation circuit 200. The positive terminal of the power diode D1 is connected to the output terminal of the high-frequency transformer T, and its negative terminal is connected to the positive terminal of the output filter capacitor. The positive terminal of the output filter capacitor is connected to the output positive terminal and the negative terminal of the power diode D1, and its negative terminal is connected to the output negative terminal and the output terminal of the high-frequency transformer T.

[0060] In some embodiments, the modulation circuit 200 includes:

[0061] The first feedback control circuit is connected to the reference voltage and the initial output voltage of the power supply circuit. The first feedback control circuit is used to determine the voltage difference between the reference voltage and the initial output voltage of the power supply circuit, and to generate a first action signal based on the voltage difference between the reference voltage and the initial output voltage of the power supply circuit.

[0062] The second feedback control circuit is connected to the first action signal, the input signal of the power supply bus, and the intermediate frequency signal representing metadata. The second feedback control circuit is used to determine the addition result between the action signal and the intermediate frequency signal, and the signal difference between the addition result and the input signal, and to generate the second action signal based on the signal difference between the addition result and the input signal.

[0063] The communication arithmetic unit receives a second action signal and a high-frequency signal representing a communication data segment; the communication arithmetic unit is used to calculate the difference between the second action signal and the high-frequency signal to obtain a control signal.

[0064] The threshold detector receives the control signal and generates a communication signal based on the comparison result between the control signal and the threshold.

[0065] The first feedback control circuit is a feedback circuit formed for the output voltage of the power supply circuit. This first feedback control circuit can be implemented using a subtractor with subtraction function and a proportional-integral (PI) controller. The subtractor determines the voltage difference, and the PI controller adjusts according to this voltage difference to output a first action signal. The first action signal is in the form of a current.

[0066] The second feedback control circuit is a feedback circuit formed for the input signal of the bus. The first feedback control circuit can be implemented by an arithmetic logic unit (ALU) with addition and subtraction functions and a proportional-integral (PI) controller. The ALU is used to determine the addition result and the corresponding signal difference, and the PI controller is used to adjust according to the signal difference to output a second action signal. The second action signal is in the form of current.

[0067] The communication arithmetic unit is used to introduce high-frequency signals. It injects high-frequency signals simultaneously with the switching signals of the power switching transistors. This generates a control signal based on the principle of area equivalence. This process converts the second action signal into a PWM signal with equal height but unequal width; the PWM signal is the control signal.

[0068] A threshold circuit is used to obtain a corresponding communication signal based on the magnitude of the control signal. For example, a binary threshold circuit with a 0-based reference is characterized by outputting 1 when the input is greater than 0 and outputting 0 when the input is less than 0. Thus, communication is achieved by controlling the on / off state of the power switch via 0 and 1.

[0069] In this embodiment, the initial output voltage is first brought close to the reference voltage by the first feedback control circuit, so that it has the function of power supply; then the addition result between the action signal and the intermediate frequency signal is obtained by the second feedback circuit, so that the intermediate frequency signal is injected into the first action signal, so that the first action signal has the function of communication decoding; then the high frequency signal is used for processing so that the content of the communication signal is decodeable.

[0070] In some embodiments, metadata is used to generate an intermediate frequency (IF) baseband signal with each bit reversed and an inverse IF baseband signal, the sum of the product of the IF baseband signal and the first IF carrier, and the product of the inverse IF baseband signal and the second IF carrier, which is the IF signal.

[0071] The metadata generates an intermediate frequency (IF) baseband signal, which contains only 0 and 1 states and is an analog signal used to represent the original data. The inverted IF baseband signal is the opposite of each bit of the IF baseband signal.

[0072] In an exemplary embodiment, an intermediate frequency (IF) baseband inverse signal is generated simultaneously. The 0 state of the IF baseband inverse signal is equivalent to the 1 state of the IF baseband signal, and the 1 state is equivalent to the 0 state of the IF baseband signal. The IF baseband signal is multiplied by a first IF carrier, and the IF baseband inverse signal is multiplied by a second IF carrier and then added together to obtain the IF signal. The first IF carrier and the second IF carrier have different frequencies.

[0073] In this case, if a certain bit of the intermediate frequency baseband inverted signal and the intermediate frequency baseband signal is 5kHz, then that bit represents 1; if a certain bit of the intermediate frequency baseband inverted signal and the intermediate frequency baseband signal is 3.33kHz, then that bit represents 0. The multiplication and addition here are to modulate the digital 0 and 1 signals into an intermediate frequency signal band. This modulation method can achieve stronger signal anti-interference capability.

[0074] The frequency difference between the first intermediate frequency carrier and the second intermediate frequency carrier is greater than the first threshold and less than the second threshold. The difference is greater than the first threshold for the purpose of subsequent demodulation and filtering, and less than the second threshold to avoid the intermediate frequency signal being too large or too small, crossing the intermediate frequency band, and intersecting with the high frequency signal band.

[0075] In this embodiment, the intermediate frequency signal is obtained by summing the products of different intermediate frequency carriers and different intermediate frequency signals, which can achieve stronger signal anti-interference capability and avoid data loss.

[0076] In one exemplary embodiment, such as Figure 3As shown, the reference voltage Vref is subtracted from the initial output voltage Vout of the power supply circuit for digital power communication and then sent to the PI controller. The output of the PI controller is added to the intermediate frequency signal generated by metadata modulation and then subtracted from the input current Iin of the digital power communication power supply before being sent to the PI controller. The output of the PI controller is subtracted from the high frequency signal generated after data segment and triangular carrier modulation and then input to a binary threshold circuit with 0 as the reference to generate the control signal for the power switch S1.

[0077] The intermediate frequency (IF) signal is characterized by being modulated from metadata and an IF carrier. The metadata generates the IF baseband signal, which contains only 0 and 1 states. Simultaneously, it generates an inverse IF baseband signal; a 0 state in the inverse signal corresponds to a 1 state in the IF baseband signal, and vice versa. The IF baseband signal is multiplied by IF carrier 1, and the inverse IF baseband signal is multiplied by IF carrier 2. These multiplications are then summed to obtain the final IF signal, where IF carrier 1 and IF carrier 2 have different frequencies.

[0078] The high-frequency signal is characterized by being modulated from a data segment and a triangular carrier signal. The data segment signal generates a high-frequency baseband signal with only 0 and 1 states. The triangular carrier frequency is the switching frequency of the power switch S1, and the triangular carrier generates an inverted triangular carrier with the opposite phase. The triangular carrier is multiplied by the high-frequency baseband signal, and the inverted triangular carrier is also multiplied by the high-frequency baseband signal. The sum of the two results is the high-frequency signal.

[0079] The binary threshold circuit with 0 as the baseline is characterized by outputting 1 when the input is greater than 0 and outputting 0 when the input is less than 0. The output values ​​of 1 and 0 are used to control the on / off time of the power switch.

[0080] In some embodiments, the communication data is used to generate a high-frequency baseband signal, and the sum of the product of the high-frequency baseband signal and the triangular carrier, and the product of the high-frequency baseband inverse signal and the corresponding inverse triangular carrier is the high-frequency signal.

[0081] The high-frequency signal is modulated from a communication data segment and a triangular carrier signal. The data segment signal generates a high-frequency baseband signal with only 0 and 1 states, while the triangular carrier generates an inverse triangular carrier with a reversed phase. The triangular carrier is multiplied by the high-frequency baseband signal, and the inverse triangular carrier is also multiplied by the high-frequency baseband signal; the sum of the two results is the high-frequency signal. For example, the high-frequency signal is the switching frequency of a power switch transistor, such as 200 kHz.

[0082] In this embodiment, the two triangular carriers have the same frequency but different phases, and phase modulation is used. This modulation method has strong anti-interference ability because the triangular carrier frequency is high. For a single signal symbol unit length, the communication rate will be much higher than that of intermediate frequency communication, and thus the communication efficiency is higher.

[0083] In some embodiments, the frequency of the triangular carrier wave is adapted to the frequency of the power switch used to conduct the communication signal.

[0084] In one exemplary embodiment, the triangular carrier frequency is the switching frequency of the power switch, such that the frequency of the triangular carrier of the power switch is adapted to the frequency at which the filtered signal is turned on.

[0085] In this embodiment, the frequency of the triangular carrier is matched with the frequency of the filtered signal, so that high-frequency signals can be transmitted through the power switch, thereby more precisely controlling the switching on and off of the switch and realizing the transmission of communication data segments.

[0086] In some embodiments, the power supply circuit further includes a demodulation circuit, which includes a high-frequency filter circuit and different intermediate-frequency filter circuits respectively connected to the input signals of the power supply bus.

[0087] Different intermediate frequency (IF) filtering circuits are used to bandpass filter the input signal of the power supply bus into different bandpass filtered signals according to the center frequency and frequency band corresponding to different IF carriers; scale the amplitude of the different bandpass filtered signals into different scaled signals according to the scaling factor; perform low-pass filtering based on the values ​​of the different scaled signals to obtain different low-pass filtered signals; compare the different low-pass filtered signals with the decoding threshold to obtain different threshold determination results; and perform subtraction on the different threshold determination results to obtain the IF analog signal to be processed representing metadata.

[0088] The high-frequency filtering circuit is used to bandpass filter the input signal of the power supply bus into a bandpass filtered signal corresponding to the high-frequency filtering circuit, according to the frequency band corresponding to the high-frequency filtering circuit; scale the amplitude of the high-frequency bandpass filtered signal into a scaled signal of the high-frequency filtering circuit according to the high-frequency scaling factor; inject the scaled high-frequency signal into a triangular signal carrier to obtain a fused signal; perform low-pass filtering on the fused signal to obtain a low-pass filtered signal of the high-frequency filtering circuit; and compare the low-pass filtered signal of the high-frequency filtering circuit with a decoding threshold to obtain the high-frequency analog signal to be processed representing the communication data segment.

[0089] The signal processing module is used to receive the intermediate frequency analog signal and the high frequency analog signal to be processed; to perform sampling and decision processing on the intermediate frequency analog signal and the high frequency analog signal to be processed respectively to obtain the intermediate frequency baseband signal and the high frequency baseband signal to be processed; and to restore the intermediate frequency baseband signal and the high frequency baseband signal to be processed into data frames.

[0090] Bandpass filtered signals are obtained by processing with bandpass filters; different bandpass filtered signals are obtained by filtering with different bandpass filters corresponding to different intermediate frequency (IF) carriers. The IF analog signal to be processed is obtained step-by-step through different bandpass filtered signals, allowing the two signals to complement each other and making the reliability of the IF analog signal to be processed relatively strong. For example, if the digital signal to be encoded is 0, then in correct transmission, one low-pass filtered signal will be 0, and the other low-pass filtered signal will be 1. However, in reality, some judgment errors may occur, causing both to output 1, making the IF analog signal to be processed 0, indicating an error or no communication. As another example, if the digital signal to be encoded is 1, one low-pass filtered signal will be 1, and the other low-pass filtered signal will be 0. If an error occurs, causing both low-pass filtered signals to be 1, then the IF analog signal to be processed will be 0, indicating an error or no communication, and this error signal can be ignored.

[0091] Among them, bandpass filtering for intermediate frequency and high frequency can be implemented by corresponding bandpass filters, such as BPF1, BPF2, and BPF3. Each bandpass filter has upper and lower cutoff frequencies, and the bandpass portion formed by the upper and lower cutoff frequencies contains the communication signal to be filtered out. The bandpass portions of the three filters do not have any overlap.

[0092] The scaling factor is used to adjust the amplitude of various bandpass filtered signals to a suitable range. If the signal amplitude is too small, it is amplified by the scaling factor; if the signal amplitude is too small, it is reduced. If the low-pass filter output is too small or too large and affects the judgment, it needs to be adjusted. The scaled signal is a signal with an appropriate amplitude.

[0093] The value of the scaled signal is determined by the absolute value module. The value of the scaled signal includes the current corresponding to the communication signal used to represent 0 and 1, as well as the intermediate frequency (IF) or high frequency (HF) signal contained in the input signal. Therefore, the IF or HF signal is filtered out by low-pass filtering to obtain the communication signal of the corresponding frequency band.

[0094] The signal after low-pass filtering is obtained by low-pass filtering. The cutoff frequency of low-pass filtering is lower than the lowest frequency of each intermediate frequency carrier, so as to filter out the intermediate frequency signal contained in the input signal.

[0095] The decoding threshold is used to obtain a threshold determination result by comparing signal frequencies; for example, when the input is greater than a preset high point, it is determined as 1, and when the input is less than a preset low point, it is determined as 0. The intermediate frequency analog signal to be processed is an analog signal obtained by combining the determination results of different thresholds.

[0096] The frequency band corresponding to the high-frequency filter circuit contains frequencies higher than the center frequency and frequency band of different intermediate frequency carriers. The high-frequency scaling factor adjusts the amplitude of the bandpass filtered signal corresponding to the high-frequency filter circuit to an appropriate range. If the signal amplitude is too small, it is amplified by the high-frequency scaling factor; if the signal amplitude is too small, it is reduced. If the low-pass filter output is too small or too large and affects the judgment, it needs to be adjusted. The scaled signal of the high-frequency filter circuit is a high-frequency signal with an appropriate amplitude.

[0097] The fused signal is obtained by adjusting the high-frequency scaled signal onto a triangular carrier wave, enabling more efficient transmission of the corresponding communication signal. The low-pass filtered signal from the high-frequency filter circuit is obtained through low-pass filtering, and its cutoff frequency is lower than the lowest frequency of each high-frequency carrier wave, thus filtering out high-frequency signals contained in the input signal. The high-frequency analog signal is the analog signal obtained by judging the fused signal.

[0098] The sampling decision algorithm refers to the sampling decision algorithm for intermediate frequency (IF) signals. It uses the smallest time scale of 0 and 1 in the digital signal as the interval to judge each bit of the IF analog signal to be processed. If the bit is 1, it is retained as 1; if the bit is -1 or any other value, it is retained as 0; a bit of 0 is invalid. When sampling and judging the high-frequency analog signal to be processed, a bit is treated as 1 if it is 1, and 0 if it is 0, thus achieving the corresponding encoding and decoding.

[0099] Since both the intermediate frequency baseband signal and the high frequency baseband signal to be processed are composed of bits, and the metadata represents the intermediate frequency baseband signal while the communication data segment represents the high frequency baseband signal, the intermediate frequency baseband signal and the high frequency baseband signal to be processed are restored into data frames to complete the communication.

[0100] In some embodiments, different intermediate frequency (IF) filter circuits include a first IF filter circuit and a second IF filter circuit; wherein:

[0101] The first intermediate frequency (IF) filter circuit is used to bandpass filter the input signal of the power supply bus into a first bandpass filtered signal according to the center frequency corresponding to the first IF carrier; scale the amplitude of the first bandpass filtered signal into a first scaled signal according to the scaling factor; perform low-pass filtering based on the value of the first scaled signal to obtain a first low-pass filtered signal; and compare the first low-pass filtered signal with the decoding threshold to obtain a first threshold determination result.

[0102] The second intermediate frequency (IF) filter circuit is used to bandpass filter the input signal of the power supply bus into a second bandpass filtered signal based on the center frequency corresponding to the second IF carrier; scale the amplitude of the second bandpass filtered signal into a second scaled signal according to a scaling factor; perform low-pass filtering based on the value of the second scaled signal to obtain a second low-pass filtered signal; and compare the second low-pass filtered signal with a decoding threshold to obtain a second threshold determination result. The center frequency corresponding to the first IF carrier is different from the center frequency corresponding to the second IF carrier, and the first bandpass filtered signal and the second bandpass filtered signal are obtained based on filtering at different frequencies.

[0103] In some embodiments, different threshold determination results include a first threshold determination result and a second threshold determination result; in this case, the first threshold determination result and the second threshold determination result can be subtracted by the arithmetic unit used for decoding to obtain the intermediate frequency analog signal to be processed representing metadata.

[0104] In one embodiment, the digital power communication power supply input current Iin is acquired and passed through bandpass filters BPF1 and BPF2. The center frequencies of BPF1 and BPF2 are the frequencies of the first and second intermediate frequency carriers, and their bandwidths do not include the frequency of the other. After passing through BPF1 and BPF2, the signal is scaled by a coefficient k1 and then fed into an absolute value module, followed by low-pass filters LPF1 and LPF2. The cutoff frequencies of LPF1 and LPF2 must be lower than the lower frequencies of the first and second intermediate frequency carriers. The outputs of LPF1 and LPF2 are fed into a threshold determination module, and then subtracted to obtain the analog signal containing the intermediate frequency baseband signal.

[0105] The signal processing module receives an intermediate frequency analog signal to be processed containing an intermediate frequency baseband signal and a high frequency analog signal to be processed containing a high frequency baseband signal. It then restores the signal to a high frequency baseband signal and an intermediate frequency baseband signal according to a sampling decision algorithm. Finally, it restores the high frequency baseband signal and the intermediate frequency baseband signal to a data frame according to the data frame format.

[0106] In one exemplary embodiment, such as Figure 4 As shown, after the bus input current Iin of the digital power communication power supply circuit is connected, Iin is passed through bandpass filters BPF1 and BPF2. The center frequencies of BPF1 and BPF2 are the frequencies of intermediate frequency carrier 1 and intermediate frequency carrier 2, and their bandwidths do not include the frequency of the other. After passing through BPF1 and BPF2, it is amplified by coefficient k1 and then sent to the absolute value module, followed by low-pass filters LPF1 and LPF2. The cutoff frequencies of LPF1 and LPF2 must be lower than the lower frequencies of intermediate frequency carrier 1 and intermediate frequency carrier 2. The outputs of LPF1 and LPF2 are sent to the threshold determination module, and then subtracted to obtain the intermediate frequency analog signal to be processed, which includes the intermediate frequency baseband signal.

[0107] After passing Iin through the bandpass filter BPF3, it is amplified by the k2 coefficient and multiplied by the signal carrier. The result is then passed through the low-pass filter LPF3 and sent to the threshold determination module to obtain the high-frequency analog signal to be processed, which contains the high-frequency baseband signal.

[0108] The threshold determination module is characterized as follows: when the input is greater than the preset high point, it is determined as 1; when the input is less than the preset low point, it is determined as 0.

[0109] The signal processing module receives analog signals containing intermediate frequency (IF) baseband signals and analog signals containing high-frequency (HF) baseband signals. It then uses a sampling decision algorithm to restore these signals to HF and IF baseband signals, and finally reconstructs them into data frames according to the data frame format. This enables decoding.

[0110] In this embodiment, the intermediate frequency (IF) analog signal to be processed is gradually obtained through different bandpass filtering signals, allowing the two signals to complement each other and making the reliability of the IF analog signal to be processed relatively strong. The triangular carrier wave has the advantage of high signal transmission speed, enabling rapid transmission of the communication data segment with the largest data volume. The scaled signal has a moderate amplitude, and the scaled signal from the high-frequency filtering circuit is also a high-frequency signal with a moderate amplitude, ensuring the accuracy of recognition. Finally, the signal is restored using appropriate low-pass filtering and sampling decision algorithms to achieve encoding and decoding.

[0111] In one embodiment, such as Figure 5 As shown, this application also provides a DC-DC converter for powering a DC microgrid. One end of the DC-DC converter is connected to the input signal of the power supply bus, and the other end is connected to a distributed load. The power supply of the DC-DC converter includes multiple power supply circuits in any of the embodiments. Each power supply circuit can be a digital power communication power supply.

[0112] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0113] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0114] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A power supply circuit, characterized in that, The power supply circuit includes a filter module, a modulation circuit, and a flyback transformer module; The filtering module is used to filter out high-frequency signals based on the input signal of the power supply bus of the power supply circuit to obtain a filtered signal. The modulation circuit is used to adjust the voltage difference between the initial output voltage and the reference voltage of the power supply circuit based on the intermediate frequency signal representing metadata and the high frequency signal representing a communication data segment, so as to obtain a communication signal representing the communication data segment; the frequency of the intermediate frequency signal is higher than the frequency of the high frequency signal. The flyback transformer module is used to adjust the filtered signal according to the timing of the communication signal being turned on, and to transform the adjusted filtered signal to obtain the target output voltage of the power supply circuit; the target output voltage is used to power the DC-DC converter for communication; the initial output voltage is the output voltage generated before the target output voltage.

2. The power supply circuit according to claim 1, characterized in that, The flyback transformer module includes a high-frequency transformer and a power switch. The input terminal of the high-frequency transformer is connected to the filter module, the filter module is connected to the positive terminal of the power supply bus, the output terminal of the high-frequency transformer is connected to the drain of the power switch, the source of the power switch is connected to the negative terminal of the power supply bus, the gate of the power switch is connected to the modulation circuit, and the gate of the power switch is used to receive the communication signal.

3. The power supply circuit according to claim 2, characterized in that, The filtering module includes a filtering inductor and an input filtering capacitor. The filtering inductor is connected between the positive terminal of the power supply bus and the positive terminal of the input filtering capacitor, and the negative terminal of the input filtering capacitor is connected to the negative terminal of the power supply bus. The input terminal of the flyback transformer module is connected to the positive terminal of the input filtering capacitor. The frequency of the high-frequency signal is negatively correlated with the product of the filtering inductor and the input filtering capacitor.

4. The power supply circuit according to claim 2, characterized in that, The flyback transformer module also includes a power diode and an output filter capacitor; the positive terminal of the power diode is connected to the output terminal of the high-frequency transformer, the negative terminal of the power diode is connected to the positive terminal of the output filter capacitor, and the negative terminal of the power diode is connected to the output positive terminal of the flyback transformer module; the negative terminal of the output filter capacitor is connected to the output negative terminal of the flyback transformer module and the output terminal of the high-frequency transformer.

5. The power supply circuit according to claim 1, characterized in that, The modulation circuit includes: A first feedback control circuit is connected to a reference voltage and the initial output voltage of the power supply circuit. The first feedback control circuit is used to determine the voltage difference between the reference voltage and the initial output voltage of the power supply circuit, and to generate a first action signal based on the voltage difference between the reference voltage and the initial output voltage of the power supply circuit. The second feedback control circuit is connected to the first action signal, the input signal of the power supply bus, and the intermediate frequency signal representing metadata. The second feedback control circuit is used to determine the addition result between the action signal and the intermediate frequency signal, and the signal difference between the addition result and the input signal, and generate a second action signal based on the signal difference between the addition result and the input signal. A communication arithmetic unit, wherein the communication arithmetic unit receives the second action signal and the high-frequency signal representing the communication data segment; the communication arithmetic unit is used to calculate the difference between the second action signal and the high-frequency signal to obtain a control signal; A thresholder is provided, which receives the control signal and generates the communication signal based on the comparison result between the control signal and the threshold.

6. The power supply circuit according to claim 1, characterized in that, The metadata is used to generate an intermediate frequency (IF) baseband signal and an inverse IF baseband signal with opposite bits. The sum of the product of the IF baseband signal and the first IF carrier, and the product of the inverse IF baseband signal and the second IF carrier, is the IF signal.

7. The power supply circuit according to claim 1, characterized in that, The communication data is used to generate a high-frequency baseband signal. The sum of the product of the high-frequency baseband signal and the triangular carrier, and the product of the high-frequency baseband inverse signal and the corresponding inverse triangular carrier, is the high-frequency signal.

8. The power supply circuit according to claim 7, characterized in that, The frequency of the triangular carrier wave is adapted to the frequency of the power switch used to turn on the communication signal.

9. The power supply circuit according to claim 1, characterized in that, It also includes a demodulation circuit, which includes a high-frequency filter circuit and different intermediate-frequency filter circuits respectively connected to the input signals of the power supply bus; The different intermediate frequency filtering circuits are used to bandpass filter the input signal of the power supply bus into different bandpass filtered signals according to the center frequency and frequency band corresponding to different intermediate frequency carriers. According to the scaling factor, the amplitudes of the different bandpass filtered signals are scaled into different scaled signals; low-pass filtering is performed based on the values ​​of the different scaled signals to obtain different low-pass filtered signals; the different low-pass filtered signals are compared with the decoding threshold to obtain different threshold determination results; the different threshold determination results are subtracted to obtain the intermediate frequency analog signal to be processed representing metadata; A high-frequency filtering circuit is used to bandpass filter the input signal of the power supply bus into a bandpass filtered signal corresponding to the high-frequency filtering circuit according to the frequency band corresponding to the high-frequency filtering circuit; and to scale the amplitude of the bandpass filtered signal corresponding to the high frequency into the scaled signal of the high-frequency filtering circuit according to the high-frequency scaling factor. The high-frequency scaled signal is injected into a triangular signal carrier to obtain a fused signal; the fused signal is low-pass filtered to obtain a low-pass filtered signal from the high-frequency filtering circuit; the low-pass filtered signal from the high-frequency filtering circuit is compared with a decoding threshold to obtain a high-frequency analog signal to be processed representing a communication data segment. The signal processing module is used to receive the intermediate frequency analog signal to be processed and the high frequency analog signal to be processed; to perform sampling and decision processing on the intermediate frequency analog signal to be processed and the high frequency analog signal to be processed respectively to obtain the intermediate frequency baseband signal to be processed and the high frequency baseband signal to be processed; and to restore the intermediate frequency baseband signal to be processed and the high frequency baseband signal to be processed into a data frame.

10. A DC-DC converter, characterized in that, For power supply of DC microgrid, one end of the DC-DC converter is connected to the input signal of the power supply bus, and the other end of the DC-DC converter is connected to the distributed load. The power supply of the DC-DC converter includes the power supply circuit of any one of claims 1-9.

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