An isolated power supply circuit and an electric energy meter

Abstract

This invention relates to the field of switching power supply technology, specifically providing an isolated power supply circuit aimed at solving the problems of low integration, poor output consistency, and high cost and energy consumption in existing multi-channel isolated power supplies. To this end, the invention comprises: a power control and drive module, an isolation module, a rectification, filtering, and voltage regulation module, an anti-interference module, and a load module. The power control and drive module receives power, generates a drive voltage signal, and outputs the drive voltage signal to the isolation module, while simultaneously outputting a ground potential voltage signal to the anti-interference module. The isolation module achieves voltage signal isolation output through internal electromagnetic coupling, outputting the isolated voltage signal to the rectification and filtering module. The anti-interference module outputs the filtered, interference-free ground potential voltage signal to the rectification and filtering module. The rectification and filtering module performs rectification and filtering processes, outputting a stable voltage signal to the load module. This invention features high integration and high output consistency.

Description

Technical Field

[0001] This invention relates to the field of switching power supply technology, and specifically provides an isolated power supply circuit. Background Technology

[0002] Against the backdrop of rapid development in power electronics technology, high-end applications such as industrial control, precision instruments, and high-voltage pulse equipment have placed higher technical demands on multi-channel isolated power supply circuits. These circuits not only require reliable multi-channel electrical isolation to ensure the safety of equipment operation and personnel, but also demand core characteristics such as high-precision current sampling, stable multi-channel voltage output, and miniaturized integration. Simultaneously, they must balance energy transmission efficiency and long-term reliability. Existing technical solutions are no longer adequate for the comprehensive needs of these high-end applications. Currently, the mainstream multi-channel isolated power supply circuits on the market employ a sensor sampling combined with a power frequency isolation transformer. While this solution achieves basic electrical isolation and current sampling functions, it has revealed numerous insurmountable defects in practical applications, becoming a significant obstacle to the technology's widespread adoption.

[0003] When using sensors as sampling elements, their inherent resistance to external magnetic field interference is weak, resulting in sampling errors generally exceeding 0.5%. This fails to meet the stringent high-precision sampling requirements of precision power supply scenarios. Furthermore, the selection of sampling elements like Hall effect sensors directly increases the hardware cost of the circuit, hindering its large-scale adoption. Traditional power frequency isolation transformers, limited by their inherent operating frequency, are not only bulky and heavy, making it difficult to meet the practical needs of miniaturized equipment integration, but also suffer from low energy transmission efficiency, leading to excessive energy consumption during long-term circuit operation. This increases operating costs and contradicts the energy-saving trend in power electronics. In addition, existing solutions lack targeted multi-output calibration designs, resulting in significant differences in output voltages across different channels. This directly leads to poor on / off synchronization of downstream IGBTs, MOSFETs, and other switching devices, significantly increasing the risk of device breakdown and damage. Consequently, the overall output stability of the circuit is insufficient, and long-term reliability cannot be guaranteed.

[0004] More importantly, existing multi-channel isolated power supply circuits have not achieved a collaborative optimization design between dedicated driver chips and high-precision sampling components. Their overall topology is fragmented, failing to achieve an effective balance between electrical isolation reliability, current sampling accuracy, circuit integration, and energy transfer efficiency. This core design flaw makes it difficult for existing solutions to simultaneously meet the various technical requirements of high-end applications, and significantly restricts the application expansion of multi-channel isolated power supply circuits in high-end fields such as industrial control and precision instruments. Therefore, developing a multi-channel isolated power supply circuit that can solve many of the shortcomings of existing technologies while meeting the requirements of high precision, high stability, miniaturization, low power consumption, and high integration has become an urgent technical problem to be solved in the field of power electronics. Summary of the Invention

[0005] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problems of low integration, poor output consistency, and high cost and energy consumption of existing multi-channel isolated power supplies.

[0006] In a first aspect, the present invention provides an isolated power supply circuit, comprising: a power control drive module, an isolation module, a rectification, filtering, and voltage regulation module, an anti-interference module, and a load module. The power control drive module receives power, generates a drive voltage signal, and outputs the drive voltage signal to the isolation module, while simultaneously outputting a ground potential voltage signal to the anti-interference module. The isolation module achieves voltage signal isolation output through internal electromagnetic coupling, outputting the isolated voltage signal to the rectification and filtering module. The anti-interference module outputs a filtered, interference-free ground potential voltage signal to the rectification and filtering module. The rectification and filtering module performs rectification and filtering processes, then outputs a stable voltage signal to the load module.

[0007] In one technical solution of the above power supply circuit, the power control drive module includes: a power supply, a primary side common ground, a drive chip, a first capacitor, and a second capacitor. The drive chip includes a selection pin, an enable pin, a power supply pin, a ground pin, a first output pin, and a second output pin. When the drive chip operates in the low-frequency range, the selection pin is left floating. The enable pin and the power supply pin are connected to the power supply. The ground pin is connected to the primary side common ground. The first output pin and the second output pin output drive voltage signals. The first plate of the first capacitor is connected to the input power supply, and the second plate of the first capacitor is connected to the primary side common ground. The first plate of the second capacitor is connected to the input power supply, and the second plate of the second capacitor is connected to the primary side common ground.

[0008] In one technical solution of the power supply circuit described above, when the driver chip operates in the intermediate frequency band, it further includes a first resistor, the first end of which is connected to the power supply, and the second end of which is connected to the selection pin.

[0009] In one technical solution of the above power supply circuit, when the driver chip operates at high frequency, it also includes a second resistor. The first end of the second resistor is connected to the common ground terminal of the primary side, and the second end of the second resistor is connected to the selection pin.

[0010] In one technical solution of the above power supply circuit, the isolation module includes: a third capacitor, a fourth capacitor, a primary common ground terminal, and multiple isolation transformers. The first plate of the third capacitor is connected to the first output pin, and the second plate of the third capacitor is connected to the primary common ground terminal. The first plate of the fourth capacitor is connected to the second output pin, and the second plate of the fourth capacitor is connected to the primary common ground terminal. The first and second ends of the primary windings of the multiple isolation transformers are connected in parallel between the first and second output pins. Multiple secondary windings are magnetically coupled to the primary windings of the multiple isolation transformers, and the multiple secondary windings output isolated voltage signals.

[0011] In one technical solution of the above power supply circuit, the rectifier, filter, and voltage regulator module includes: a rectifier bridge, a filter capacitor, and an independent ground terminal on the secondary side. The first output terminal of the secondary winding is connected to the first AC terminal of the rectifier bridge, and the second output terminal is connected to the second AC terminal of the rectifier bridge. The DC output terminal of the rectifier bridge is connected to the first plate of the filter capacitor, and the ground terminal of the rectifier bridge is connected to the second plate of the filter capacitor. The ground terminal of the rectifier bridge is connected to the corresponding independent ground terminal on the secondary side, and the DC output terminal of the rectifier bridge outputs a stable voltage signal.

[0012] In one technical solution of the above power supply circuit, the rectifier bridge includes a first rectifier half-bridge dual diode and a second rectifier half-bridge dual diode. The first output terminal of the secondary winding is connected to the common terminal of the first rectifier bridge dual diode, and the second output terminal of the secondary winding is connected to the common terminal of the second rectifier bridge dual diode. The upper cathode terminal of the first rectifier bridge dual diode and the upper cathode terminal of the second rectifier bridge dual diode are connected together. A first plate with a filter capacitor is connected to the second plate with a filter capacitor. The lower anode terminal of the first rectifier bridge dual diode is connected to the lower anode terminal of the rectifier bridge dual diode, and a second plate with a filter capacitor is connected to the second plate with the filter capacitor. The lower anode terminal of the first rectifier bridge dual diode and the lower anode terminal of the rectifier bridge dual diode are connected to the corresponding independent ground terminal of the secondary side.

[0013] In one technical solution of the above power supply circuit, the anti-interference module includes a Class Y safety capacitor, wherein the first terminal of the Class Y safety capacitor is connected to the common ground terminal of the primary side, and the second terminal is connected to the corresponding independent ground terminal of the secondary side.

[0014] In one technical solution of the above power supply circuit, the load module includes: an LDO chip, a metering chip, a secondary independent ground, and a manganese copper sampling resistor, wherein the DC output terminal of the rectifier bridge is connected to the input terminal of the LDO chip, the output terminal of the LDO chip is connected to the power supply terminal of the metering chip, the two ends of the manganese copper sampling resistor are respectively connected to the two current sampling input terminals of the metering chip, and the ground terminals of the LDO chip and the metering chip are both connected to the corresponding secondary independent ground.

[0015] In one technical solution of the above power supply circuit, multiple input filter capacitors are connected in parallel between the input terminal of the LDO chip and the corresponding independent ground terminal on the secondary side, and multiple output filter capacitors are connected in parallel between the output terminal of the LDO chip and the corresponding independent ground terminal on the secondary side.

[0016] In a second aspect, the present invention provides an electricity meter, comprising: a display unit, an electricity metering unit, a power supply unit, and a data processing control unit, wherein the power supply unit supplies power to the display unit, the electricity metering unit, and the data processing control unit, and wherein the power supply unit is the aforementioned power supply circuit.

[0017] By employing the above technical solution, this invention achieves significant technical results by setting up a dedicated driver chip paired with an isolation transformer module, combining three independent rectifier, filter, and voltage regulator modules with manganese copper sampling to form a collaborative topology, supplemented by optimized winding processes, anti-interference components, and multiple protection designs. Simultaneously, it incorporates a frequency band adjustment structure and a voltage regulator chip, comprehensively optimizing the technical problems of existing multi-channel isolated power supplies. The isolation transformer uses an optimized winding process to reduce leakage inductance and improve electrical isolation performance. Compared to traditional power frequency transformers, it significantly reduces the overall circuit size and increases integration. Combined with the drive signal from the dedicated driver chip, it effectively improves energy transmission efficiency, and the chip's built-in protection functions further enhance the reliability of the circuit. The multiple independent rectifier, filter, and voltage regulator modules, along with rectifier and filter components, output a stable voltage after secondary voltage regulation by the voltage regulator chip. This effectively ensures the consistency of the multiple output voltages, improves the synchronization of subsequent load switching, significantly reduces the risk of device breakdown and damage, and enhances the overall output stability and service life of the circuit. This application replaces traditional high-cost sensors with manganese copper sampling, and reduces the overall hardware cost of the circuit by combining it with a modular topology design. The inclusion of anti-interference components effectively suppresses electromagnetic interference and helps ensure the safety of circuit isolation. The closed-loop feedback design further enhances the circuit's anti-interference capability, making it suitable for precision power supply scenarios. Simultaneously, the frequency band adjustment structure allows for flexible adjustment of the operating frequency band to adapt to different application scenarios, and the optimized energy efficiency design reduces the energy consumption of the circuit during long-term operation. Ultimately, this achieves the technical goals of miniaturization, high integration, high stability, low energy consumption, and low cost for multi-channel isolated power supplies, making it suitable for high-end applications such as industrial control and precision instruments. Attached Figure Description

[0018] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0019] Figure 1 This is a schematic diagram of an isolated power supply circuit according to the present invention;

[0020] Figure 2 This is a schematic diagram of the anti-interference module of the present invention;

[0021] Figure 3 This is a schematic diagram of the load module of the present invention;

[0022] Figure 4 This is a schematic diagram of the mid-frequency band connection of the power control drive module of the present invention;

[0023] Figure 5 This is a schematic diagram of the high-frequency connection of the power control drive module of the present invention. Detailed Implementation

[0024] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0025] It should be noted that in the description of this invention, terms such as "bottom" that indicate direction or positional relationship are based on the direction or positional relationship shown in the accompanying drawings. This is merely for ease of description and does not indicate or imply that the relevant device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of this invention. Furthermore, ordinal numbers such as "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] Furthermore, it should be noted that although the various steps of the control method of the present invention are described in a specific order in the description of the present invention, these orders are not restrictive. Without departing from the basic principles of the present invention, those skilled in the art can perform the steps in different orders.

[0027] like Figure 1 , Figure 2 , Figure 3The diagram shown is a circuit diagram of an isolated power supply circuit according to the present invention, including a power control and drive module, an isolation module, a rectification, filtering, and voltage regulation module, an anti-interference module, and a load module. The power control and drive module receives power, generates a drive voltage signal, and outputs the drive voltage signal to the isolation module, while simultaneously outputting a ground potential voltage signal to the anti-interference module. The isolation module achieves voltage signal isolation output through internal electromagnetic coupling, outputting the isolated voltage signal to the rectification and filtering module. The anti-interference module outputs the filtered, interference-free ground potential voltage signal to the rectification and filtering module. The rectification and filtering module performs rectification and filtering processes, outputting a stable voltage signal to the load module.

[0028] In some embodiments, the power control drive module includes: a power supply, a primary-side common ground, a drive chip, a first capacitor, and a second capacitor. The drive chip includes a selection pin, an enable pin, a power supply pin, a ground pin, a first output pin, and a second output pin. When the drive chip operates at low frequencies, the selection pin is left floating. The enable pin and the power supply pin are connected to the power supply. The ground pin is connected to the primary-side common ground. The first and second output pins output drive voltage signals. The first plate of the first capacitor is connected to the input power supply, and the second plate of the first capacitor is connected to the primary-side common ground. The first plate of the second capacitor is connected to the input power supply, and the second plate of the second capacitor is connected to the primary-side common ground. In a preferred embodiment, as shown... Figure 1 As shown, the driver chip selected is the DM6504. The corresponding pin assignments in the diagram are as follows: select pin is SEL, enable pin is EN, power supply pin is VDD, ground pin is GND, first output pin is VB1, and second output pin is VB2. The corresponding circuit components used with the DM6504 chip, in this specific embodiment, are: first capacitor C3 and second capacitor C4. This chip can operate in different frequency modes, which can be selected and adjusted according to actual needs. Specifically, the frequency operating mode is selected by connecting different inputs to the select pin (SEL), thereby adjusting the chip's frequency. In this specific embodiment, the connection method for adjusting the chip's frequency operating mode is as follows: Figure 1 As shown, the SEL pin is left floating at this time. The chip operates according to its own frequency. At this time, the DM6504 chip operates in the low frequency band, with a spread spectrum range of 212-440 kHz.

[0029] In some embodiments, the DM6504 chip can also be selected to operate in the intermediate frequency band, such as... Figure 4As shown, the circuit also includes a first resistor, with its first end connected to the power supply and its second end connected to the selection pin. In a specific embodiment, the first resistor... Figure 4 The corresponding relationship is as follows: the first resistor is R3. At this time, the SEL input terminal of the chip is connected to receive the signal transmitted through R3, and then selects the intermediate frequency working mode. At this time, the spread spectrum range is 240-480 kHz.

[0030] In some embodiments, the DM6504 chip can also be selected to operate in the intermediate frequency band, such as... Figure 5 As shown, the circuit also includes a second resistor. The first terminal of the second resistor is connected to the primary side common ground, and the second terminal of the second resistor is connected to the selection pin. In a specific embodiment, the second resistor... Figure 5 The corresponding relationship is as follows: the second resistor is R4. At this time, the DM6504 chip selects the high-frequency operating mode, and the frequency range is 266-500 kHz. The power control drive module, as the core control unit of the circuit, regulates the on / off of energy transmission through the output drive signal and realizes the overall control of the circuit's operating state. At the same time, it integrates fault protection functions, which not only accurately improves the energy transmission efficiency of the circuit, but also effectively avoids faults such as overcurrent and overvoltage, greatly enhancing the overall reliability and stability of the circuit operation.

[0031] In some embodiments, the isolation module includes: a third capacitor, a fourth capacitor, a primary common ground terminal, and multiple isolation transformers. The first plate of the third capacitor is connected to the first output pin, and the second plate of the third capacitor is connected to the primary common ground terminal. The first plate of the fourth capacitor is connected to the second output pin, and the second plate of the fourth capacitor is connected to the primary common ground terminal. The first and second ends of the primary windings of the multiple isolation transformers are connected in parallel between the first and second output pins. Multiple secondary windings are magnetically coupled to the primary windings of the multiple isolation transformers, and the multiple secondary windings output isolated voltage signals. In a preferred embodiment, as shown... Figure 1As shown, in this embodiment, three isolation transformers are selected, forming a three-way isolated power supply circuit. The specific component correspondence is as follows: the primary common ground terminal is GND. The third capacitor is C5, the fourth capacitor is C6, and the multiple isolation transformers are T1, T2, and T3. The primary windings N1 of each of the three isolation transformers are connected in parallel between the two output pins VB1 and VB2 of the DM6504 chip. The primary windings are electromagnetically coupled to the corresponding secondary windings, N2, at terminals 3 and 4. The power control drive module and the isolation module are based on the DM6504 chip. The PWM output terminal of the DM6504 chip is connected to the primary winding of the isolation transformer module to generate PWM drive signals, control the on / off state of the transformer primary current, and provide overcurrent and overvoltage protection functions. The isolation transformer uses a ferrite core. The primary winding receives the drive signal from the DM6504 chip, while the secondary winding has three independent windings, each corresponding to one of the three outputs. The winding turns ratio is designed according to the voltage requirements of the three outputs. A sandwich winding method is used to reduce leakage inductance, improve energy transmission efficiency, and enhance isolation performance. The isolation voltage is ≥5kV. The isolation module achieves electrical isolation between circuit inputs and outputs, as well as between each output. It also plays a crucial role in high-frequency energy transmission and voltage division adaptation. While ensuring electrical safety for equipment operation and personnel, it significantly reduces circuit size, increases integration, optimizes energy transmission efficiency, and effectively guarantees the electrical independence of each output.

[0032] In some embodiments, the rectifier-filter-regulator module includes: a rectifier bridge, a filter capacitor, and an independent secondary-side ground terminal. The first output terminal of the secondary winding is connected to the first AC terminal of the rectifier bridge, and the second output terminal is connected to the second AC terminal of the rectifier bridge. The DC output terminal of the rectifier bridge is connected to the first plate of the filter capacitor, and the ground terminal of the rectifier bridge is connected to the second plate of the filter capacitor. The ground terminal of the rectifier bridge is also connected to the corresponding independent secondary-side ground terminal. The DC output terminal of the rectifier bridge outputs a stable voltage signal. In a preferred embodiment, as shown... Figure 1As shown, since the number of rectifier-filter-regulator modules corresponds to the number of isolation transformers, with three isolation transformers (i.e., three isolation circuits), three sets of rectifier bridges and filter capacitors are designed accordingly. Each set of rectifier-filter-regulator modules also has an independent ground terminal. Furthermore, in specific embodiments, the rectifier bridges can also be implemented using existing rectifier half-bridge type dual-diode packaged components, which is more convenient and results in a simpler, more integrated circuit. When using two rectifier half-bridge type dual diode packaged elements to replace the rectifier bridge, the specific connection relationship is as follows: the rectifier bridge includes a first rectifier half-bridge type dual diode and a second rectifier half-bridge type dual diode. The first output terminal of the secondary winding is connected to the common terminal of the first rectifier half-bridge type dual diode, the second output terminal of the secondary winding is connected to the common terminal of the second rectifier half-bridge type dual diode, the upper cathode terminal of the first rectifier half-bridge type dual diode and the upper cathode terminal of the second rectifier half-bridge type dual diode are connected, and a first plate with a filter capacitor is connected. The lower anode terminal of the first rectifier half-bridge type dual diode is connected to the lower anode terminal of the rectifier half-bridge type dual diode, and a second plate with a filter capacitor is connected. The lower anode terminal of the first rectifier half-bridge type dual diode and the lower anode terminal of the rectifier half-bridge type dual diode are connected to the corresponding independent ground terminal on the secondary side.

[0033] In a specific preferred embodiment, the correspondence between the components is as follows: Figure 1 As shown, three sets of rectifier-filter-regulator modules are specifically set up for the three isolation transformers. In the first rectifier-filter-regulator module, the first rectifier half-bridge dual diode is D1, the second rectifier half-bridge dual diode is D2, and the filter capacitor is C1. The independent ground terminal on the secondary side of this module is the GNDC terminal. Similarly, in the second rectifier-filter-regulator module, the first rectifier half-bridge dual diode is D3, the second rectifier half-bridge dual diode is D4, and the filter capacitor is C2. The independent ground terminal on the secondary side of this module is the GNDB terminal. In the third rectifier-filter-regulator module, the first rectifier half-bridge dual diode is D5, the second rectifier half-bridge dual diode is D6, and the filter capacitor is C7. The independent ground terminal on the secondary side of this module is the GNDA terminal. Each output circuit in the three rectifier-filter-regulator modules corresponds to a set of rectifier-filter circuits, including fast recovery rectifier diodes and a capacitor filter network. To ensure the accuracy and stability of the three-channel output voltage, the ripple factor is ≤0.5%. The rectifier and filter module rectifies, filters, and regulates the power transmitted from the isolation module, completing the conversion to adapt to the power requirements of the subsequent stage. This effectively reduces output voltage ripple, ensures the consistency and accuracy of the multiple output voltages, improves the on / off synchronization of the subsequent load, significantly reduces the risk of damage to subsequent components, and significantly improves the circuit output stability.

[0034] In some embodiments, the anti-interference module includes a Class Y safety capacitor, wherein a first terminal of the Class Y safety capacitor is connected to the primary side common ground, and a second terminal is connected to the corresponding secondary side independent ground. In a preferred embodiment, such as... Figure 2 As shown, a three-way isolated power supply circuit is equipped with three corresponding anti-interference modules. The first anti-interference module uses a Class Y safety capacitor, C12, where the first terminal of C12 is connected to the primary side common ground (GND), and the second terminal is connected to the corresponding secondary side independent ground (GNDC). The second anti-interference module uses a Class Y safety capacitor, C13, where the first terminal of C13 is connected to the primary side common ground (GND), and the second terminal is connected to the corresponding secondary side independent ground (GNDB). The third anti-interference module uses a Class Y safety capacitor, C14, where the first terminal of C14 is connected to the primary side common ground (GND), and the second terminal is connected to the corresponding secondary side independent ground (GNDA). The core function of the Y capacitor is to suppress common-mode electromagnetic interference and simultaneously ensure the safety of circuit isolation. It is specifically designed to suppress electromagnetic interference generated during circuit operation and resist external magnetic field interference, ensuring circuit isolation performance and power supply and sampling accuracy. It effectively improves the overall anti-interference capability of the circuit, reduces power supply and sampling errors, and also helps to enhance the isolation safety of the circuit. It can meet the high precision and high stability requirements of precision power supply scenarios.

[0035] In some specific embodiments, the load module includes: an LDO chip, a metering chip, a secondary-side independent ground, and a manganin sampling resistor. The DC output terminal of the rectifier bridge is connected to the input terminal of the LDO chip, the output terminal of the LDO chip is connected to the power supply terminal of the metering chip, and the two ends of the manganin sampling resistor are respectively connected to the two current sampling input terminals of the metering chip. The ground terminals of both the LDO chip and the metering chip are connected to their respective secondary-side independent grounds. Multiple input filter capacitors are connected in parallel between the input terminal of the LDO chip and its corresponding secondary-side independent ground, and multiple output filter capacitors are connected in parallel between the output terminal of the LDO chip and its corresponding secondary-side independent ground. In a preferred embodiment, such as... Figure 3As shown, to complement the three-way isolated power supply circuit, three load modules are correspondingly configured. Specifically, in the first load module, the LDO chip is UQ1, with an independent GNDC terminal on the secondary side, multiple input filter capacitors CN1 and CN2, and multiple output filter capacitors CQ1 and CQ2. In the second load module, the LDO chip is UQ2, with an independent GNDB terminal on the secondary side, multiple input filter capacitors CN3 and CN4, and multiple output filter capacitors CQ3 and CQ4. In the first load module, the LDO chip is UQ3, with an independent GNDA terminal on the secondary side, multiple input filter capacitors CN5 and CN6, and multiple output filter capacitors CQ5 and CQ6. As the terminal power receiving and adaptation unit of the circuit, the load module receives regulated power to provide accurate and stable power supply for downstream metering and other devices. In some embodiments, it also integrates a manganese copper sampling structure. Manganese copper has the advantages of high sampling accuracy, strong anti-interference, and low hardware cost, replacing traditional high-cost sensors. This ensures the accuracy of sampling and detection by the downstream metering chip, perfectly adapts to the sampling requirements of precision power supply scenarios, and effectively reduces the overall hardware cost of the circuit. At the same time, the modular design enables precise power distribution, ensuring the normal operation of various downstream devices, greatly improving the adaptability and practicality of the circuit, and making it compatible with the power needs of different high-end application scenarios such as industrial control and precision instruments.

[0036] This application addresses the technical problems of existing multi-channel isolated power supply circuits, such as low integration, poor output consistency, high cost and energy consumption, and weak anti-interference capability. It innovatively designs a modular, collaborative three-channel isolated power supply circuit. Through an integrated topology design of power control drive, isolation, rectification, filtering and voltage regulation, anti-interference, and load modules, it achieves functional complementarity and performance synergy among the modules, fundamentally solving the technical challenges of traditional solutions that cannot simultaneously achieve isolation reliability, miniaturized integration, stable output, and cost-effectiveness. This solution abandons the traditional combination of power frequency transformers and Hall sensors, adopting a high-frequency isolation design combined with a manganese copper sampling structure, significantly improving circuit integration, reducing overall size, and effectively lowering hardware costs and energy transmission losses, achieving low-energy operation. Each module in the circuit performs its specific function while working closely together. The control and drive module ensures precise regulation of energy transmission and fault protection; the isolation module strengthens electrical safety and optimizes energy transmission efficiency; the rectification, filtering, and voltage regulation module ensures high precision and consistency of the three output voltages, reducing the risk of damage to downstream components; the anti-interference module enhances the circuit's resistance to electromagnetic interference, ensuring power supply and sampling accuracy; and the load module leverages the high precision and high anti-interference advantages of manganese copper sampling to meet the sampling requirements of precision scenarios. The overall solution combines the core advantages of high integration, small size, high stability, low power consumption, and low cost. Furthermore, the modular design enhances the circuit's adaptability to various scenarios, perfectly meeting the comprehensive needs of high-end applications such as industrial control and precision instruments for electrical isolation, stable power supply, and high-precision sampling of multiple isolated power supplies. Its practicality and promotional value are significant.

[0037] In another aspect of this application, an electricity meter is also provided, comprising: a display unit, an electricity metering unit, a power supply unit, and a data processing control unit, wherein the power supply unit supplies power to the display unit, the electricity metering unit, and the data processing control unit, and wherein the power supply unit is the aforementioned power supply circuit.

[0038] The technical solution of the present invention has been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. An isolated power supply circuit, characterized in that, include: The system includes a power control drive module, an isolation module, a rectification, filtering and voltage regulation module, an anti-interference module and a load module. The power control drive module receives power, generates a drive voltage signal, outputs the drive voltage signal to the isolation module, and simultaneously outputs a ground potential voltage signal to the anti-interference module. The isolation module achieves voltage signal isolation output through internal electromagnetic coupling, and outputs the isolated voltage signal to the rectification and filtering module. The anti-interference module outputs the filtered interference-free ground potential voltage signal to the rectification and filtering module. After rectification and filtering, the rectification and filtering module outputs a stable voltage signal to the load module.

2. The power supply circuit according to claim 1, characterized in that, The power control drive module includes: a power supply, a primary side common ground, a drive chip, a first capacitor, and a second capacitor. The drive chip includes a selection pin, an enable pin, a power supply pin, a ground pin, a first output pin, and a second output pin. When the drive chip operates in the low-frequency range, the selection pin is left floating. The enable pin and the power supply pin are connected to the power supply. The ground pin is connected to the primary side common ground. The first and second output pins output drive voltage signals. The first plate of the first capacitor is connected to the input power supply, and the second plate of the first capacitor is connected to the primary side common ground. The first plate of the second capacitor is connected to the input power supply, and the second plate of the second capacitor is connected to the primary side common ground.

3. The power supply circuit according to claim 2, characterized in that, When the driver chip operates in the intermediate frequency band, it also includes a first resistor, the first end of which is connected to the power supply, and the second end of which is connected to the selection pin.

4. The power supply circuit according to claim 2, characterized in that, When the driver chip operates at high frequency, it also includes a second resistor. The first end of the second resistor is connected to the primary side common ground, and the second end of the second resistor is connected to the selection pin.

5. The power supply circuit according to claim 2, characterized in that, The isolation module includes a third capacitor, a fourth capacitor, a primary common ground terminal, and multiple isolation transformers. The first plate of the third capacitor is connected to the first output pin, and the second plate of the third capacitor is connected to the primary common ground terminal. The first plate of the fourth capacitor is connected to the second output pin, and the second plate of the fourth capacitor is connected to the primary common ground terminal. The first and second ends of the primary windings of the multiple isolation transformers are connected in parallel between the first and second output pins. Multiple secondary windings are magnetically coupled to the primary windings of the multiple isolation transformers, and the multiple secondary windings output isolated voltage signals.

6. The power supply circuit according to claim 5, characterized in that, The rectifier-filter-regulator module includes a rectifier bridge, a filter capacitor, and an independent ground terminal on the secondary side. The first output terminal of the secondary winding is connected to the first AC terminal of the rectifier bridge, and the second output terminal is connected to the second AC terminal of the rectifier bridge. The DC output terminal of the rectifier bridge is connected to the first plate of the filter capacitor, and the ground terminal of the rectifier bridge is connected to the second plate of the filter capacitor. The ground terminal of the rectifier bridge is also connected to the corresponding independent ground terminal on the secondary side. The DC output terminal of the rectifier bridge outputs a stable voltage signal.

7. The power supply circuit according to claim 6, characterized in that, The rectifier bridge includes a first rectifier half-bridge dual diode and a second rectifier half-bridge dual diode. The first output terminal of the secondary winding is connected to the common terminal of the first rectifier half-bridge dual diode, and the second output terminal of the secondary winding is connected to the common terminal of the second rectifier half-bridge dual diode. The upper cathode terminal of the first rectifier half-bridge dual diode and the upper cathode terminal of the second rectifier half-bridge dual diode are connected together. A first plate with a filter capacitor is also connected to the second plate with a filter capacitor. The lower anode terminal of the first rectifier half-bridge dual diode and the lower anode terminal of the second rectifier half-bridge dual diode are connected together. A second plate with a filter capacitor is also connected to the second plate with a filter capacitor. The lower anode terminal of the first rectifier half-bridge dual diode and the lower anode terminal of the second rectifier half-bridge dual diode are connected to the corresponding independent ground terminal on the secondary side.

8. The power supply circuit according to claim 6, characterized in that, The anti-interference module includes a Class Y safety capacitor, wherein the first terminal of the Class Y safety capacitor is connected to the primary side common ground terminal, and the second terminal is connected to the corresponding secondary side independent ground terminal.

9. The power supply circuit according to claim 6, characterized in that, The load module includes: an LDO chip, a metering chip, a secondary independent ground, and a manganese copper sampling resistor. The DC output terminal of the rectifier bridge is connected to the input terminal of the LDO chip, the output terminal of the LDO chip is connected to the power supply terminal of the metering chip, the two ends of the manganese copper sampling resistor are respectively connected to the two current sampling input terminals of the metering chip, and the ground terminals of the LDO chip and the metering chip are both connected to the corresponding secondary independent ground.

10. An electricity meter, characterized in that, include: The system comprises a display unit, an energy metering unit, a power supply unit, and a data processing control unit. The power supply unit provides power to the display unit, the energy metering unit, and the data processing control unit, wherein the power supply unit is the power supply circuit described in any one of claims 1-9.

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