Voltage reduction power supply module of transformer foil winding machine control system

Abstract

The utility model discloses a step-down power supply module of a transformer foil winding machine control system. The step-down power supply module comprises a step-down controller; a two-stage input filter capacitor group; an inductor; the anode of the Schottky freewheel diode is grounded, and the cathode of the Schottky freewheel diode is connected with a node between the inductor and the switch output end of the step-down controller; the bootstrap capacitor is connected between the bootstrap end of the step-down controller and the switch output end through the shortest wire; the two-stage output filter capacitor bank comprises a high-capacity output capacitor and a low-capacity high-frequency filter capacitor and is arranged close to the output end of the inductor; the feedback voltage division network comprises a pull-up resistor and a pull-down resistor and is connected between the output end and the feedback input end of the voltage reduction controller; and the multi-pin parallel output terminal is connected with the two-stage output filter capacitor bank through a wide wire. The step-down power supply module of the transformer foil winding machine control system has the characteristics of low electromagnetic interference, high mechanical reliability and high energy efficiency.

Description

Technical Field

[0001] This utility model relates to a step-down power supply module for a transformer foil winding machine control system. Background Technology

[0002] Transformers are indispensable key equipment in modern power systems, widely used in power transmission and distribution, industrial automation, and electronic equipment. In the transformer manufacturing process, foil winding is an important winding method, particularly suitable for producing transformers with high current and low voltage. Transformer foil winding machines are precision equipment specifically designed for winding aluminum or copper foil. They ensure the quality and consistency of transformer windings by precisely controlling parameters such as tension, interlayer alignment, and winding density.

[0003] The control system of a foil winding machine is the core of the equipment, responsible for coordinating the movement of various mechanical parts, precisely controlling the tension and web-correcting mechanism, and monitoring various parameters during the winding process in real time. These control systems typically include multiple components such as a programmable logic controller (PLC), servo drivers, tension sensors, a web-correcting system, and a human-machine interface (HMI). These components require a stable and clean DC power supply. The +12V power rail is the standard power supply voltage for many industrial control systems, used to drive sensors, relays, communication interfaces, and other devices.

[0004] In traditional transformer foil winding machine control systems, the +12V power supply is mainly implemented in two ways: one is using a linear regulator (such as the 7812 series), and the other is using a switching power supply built with discrete components. Linear regulators are simple to set up, but inefficient, especially when the input voltage is much higher than the output voltage. The excess energy is dissipated as heat, wasting energy and increasing the heat load in the control cabinet. While discrete component switching power supplies are more efficient, they occupy a large space and often cause severe electromagnetic interference (EMI) due to improper layout, affecting the accuracy of sensitive sensors in the foil winding machine control system.

[0005] The working environment of foil winding machines has its own unique characteristics: on the one hand, the vibration generated by continuous high-speed operation places high demands on the mechanical reliability of electronic components; on the other hand, long-term operation can lead to an increase in temperature inside the control cabinet, accelerating the aging of electronic components. In particular, tiny metal particles generated during the processing of aluminum or copper foil can enter the control cabinet through the ventilation system, accumulate on the circuit boards, and form heat concentration points or potential short-circuit hazards.

[0006] Existing power modules face several major problems in foil winding machine control systems: First, poor electromagnetic interference control affects the measurement accuracy of tension sensors and position encoders, leading to fluctuations in winding quality; second, insufficient reliability of mechanical connections, which are prone to loosening in vibration environments, causing intermittent failures; and third, low energy efficiency, which increases the heat dissipation burden on the control cabinet, increasing maintenance frequency and costs.

[0007] Therefore, there is an urgent need for a step-down power supply module specifically designed for the control system of transformer foil winding machines, which has low electromagnetic interference characteristics, high mechanical reliability and high energy efficiency, in order to meet the special requirements of long-term and high-precision operation of foil winding machines. Utility Model Content

[0008] The purpose of this invention is to provide a step-down power supply module for a transformer foil winding machine control system. This step-down power supply module for the transformer foil winding machine control system features low electromagnetic interference, high mechanical reliability, and high energy efficiency.

[0009] The above-mentioned technical objective of this utility model is achieved through the following technical solution:

[0010] A step-down power supply module for a transformer foil winding machine control system includes: a step-down controller; a two-stage input filter capacitor bank, including a medium-capacity capacitor and a small-capacity high-frequency capacitor, arranged adjacent to the input terminal of the step-down controller; an inductor connected to the switching output terminal of the step-down controller; a Schottky freewheeling diode, with its anode grounded and its cathode connected to the node between the inductor and the switching output terminal of the step-down controller; a bootstrap capacitor connected between the bootstrap terminal and the switching output terminal of the step-down controller via the shortest possible trace; a two-stage output filter capacitor bank, including a large-capacity output capacitor and a small-capacity high-frequency filter capacitor, arranged close to the output terminal of the inductor; a feedback voltage divider network, including pull-up resistors and pull-down resistors, connected between the output terminal and the feedback input terminal of the step-down controller; and a multi-pin parallel output terminal connected to the two-stage output filter capacitor bank via a wide trace.

[0011] The present invention is further configured such that: in the dual-stage input filter capacitor bank, the medium-capacity capacitor is 10μF and the small-capacity high-frequency capacitor is 100nF.

[0012] The present invention is further configured such that the inductor is a large inductance value of 15μH, which together with the Schottky freewheeling diode forms a step-down conversion structure.

[0013] The present invention is further configured such that: in the dual-stage output filter capacitor bank, the large-capacity output capacitor is 220μF vertically mounted, and the small-capacity high-frequency filter capacitor is 100nF planar mounted, and the two are closely arranged to form a dual suppression structure for low-frequency ripple and high-frequency spike.

[0014] The present invention is further configured such that the pull-up resistor of the feedback voltage divider network is 180kΩ and the pull-down resistor is 20kΩ, configured to stabilize the output voltage at approximately 12V.

[0015] The present invention is further configured such that the multi-pin parallel output terminal includes three pins arranged in parallel, which is used to reduce contact resistance and heat concentration.

[0016] The present invention is further configured such that the routing of the feedback voltage divider network is kept at a distance from the main power loop and away from the switching output terminal of the buck controller, in order to reduce the coupling of high-frequency interference.

[0017] In summary, this utility model has the following beneficial effects:

[0018] Compact Minimum Loop Layout: This invention employs a layout with minimal loop area, consisting of a buck controller, inductor, Schottky freewheeling diode, and dual-stage output filter capacitor bank. This layout reduces the loop area compared to conventional designs, effectively lowering electromagnetic radiation according to electromagnetic field theory. Simultaneously, the bootstrap capacitor is connected between the bootstrap terminal and the switching output terminal of the buck controller via the shortest possible trace, forming a compact drive circuit and reducing switching noise. This low-EMI design is particularly important for sensitive devices such as tension sensors and position encoders in the transformer foil winding machine control system. Improved measurement accuracy ultimately translates into a significant improvement in winding quality, reducing winding defects caused by electrical noise.

[0019] Multi-stage filtering network setup: This invention employs a combination of a dual-stage input filter capacitor bank (10μF + 100nF) and a dual-stage output filter capacitor bank (220μF + 100nF), forming a comprehensive broadband filtering network. At the input end, the medium-capacity capacitors and small-capacity high-frequency capacitors are connected to the input power supply and ground via short, wide wires, forming a star grounding structure that effectively suppresses external interference from entering the system. At the output end, the large-capacity electrolytic capacitors are vertically mounted, while the small-capacity high-frequency capacitors are planar mounted; the two are closely arranged, forming a dual suppression structure for low-frequency ripple and high-frequency spikes. This multi-stage filtering setup reduces the output ripple from the conventional 100-200mV to tens of mV, a reduction of approximately 60-80%, providing a cleaner power supply for the foil winding machine control system and ensuring the accuracy and stability of the control signal.

[0020] High-efficiency energy conversion structure: This invention employs a Buck topology, combined with a 15μH high-inductance value and a Schottky freewheeling diode, forming a highly efficient energy conversion system. Compared to traditional linear regulators (such as the 7812), heat generation is reduced and the temperature rise within the control cabinet is lowered at the same output power. The low current ripple setting (only 21% of the average load current, far lower than the traditional 30-50%) further reduces system losses. This high-efficiency design not only saves energy but also reduces the workload of the cooling system, extends the lifespan of the cooling fan, reduces the frequency of maintenance due to dust inhalation, and lowers overall maintenance costs.

[0021] Enhanced mechanical connection reliability: The multi-pin parallel output terminal of this invention employs a three-pin parallel arrangement, significantly reducing contact resistance and connection point heating. This configuration is particularly suitable for the vibrating working environment of transformer foil winding machines, improving the long-term reliability of electrical connections and reducing intermittent failures caused by poor contact. These mechanical reliability features collectively enhance the module's stability under the vibration environment of the foil winding machine, reducing unexpected downtime and increasing production efficiency. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of this utility model. Detailed Implementation

[0023] The present invention will now be described in further detail with reference to the accompanying drawings.

[0024] like Figure 1 As shown, this utility model provides a step-down power supply module for a transformer foil winding machine control system, including a step-down controller (U8), a two-stage input filter capacitor bank (C8, C9), an inductor (L1), a Schottky freewheeling diode (D3), a bootstrap capacitor (C7), a two-stage output filter capacitor bank (C10, C11), a feedback voltage divider network (R30, R29), and a multi-pin parallel output terminal (H2).

[0025] The buck controller (U8) is the core control component of the entire module. The buck controller (U8) is located in the central area of ​​the circuit board, between the input and output terminals, forming the energy conversion node. Its input pin VIN (pin 7) is close to the two-stage input filter capacitor bank (C8, C9), and its output pin PH (pin 8) points towards the inductor (L1), forming the shortest power transmission path.

[0026] The dual-stage input filter capacitor bank (C8, C9) consists of a medium-capacity capacitor (C8) and a small-capacity high-frequency capacitor (C9), located adjacent to the input pin (VIN) of the buck controller (U8). The medium-capacity capacitor (C8) is 10μF, and the small-capacity high-frequency capacitor (C9) is 100nF. Both are connected to the input power supply and ground via short, wide wires, forming a star-grounded structure. This configuration allows each capacitor to leverage its filtering advantages across different frequency bands: the medium-capacity capacitor (C8) handles intermediate frequency interference, while the small-capacity high-frequency capacitor (C9) suppresses high-frequency spikes, together forming a wideband filter network from 100Hz to 10MHz.

[0027] The inductor (L1) is connected to the switching output (PH) of the buck controller (U8) and is set with a large inductance value of 15μH. The inductor (L1) is installed close to the PH (pin 8) output of the controller (U8), with one end connected to the PH pin through a short and wide trace, and the other end pointing to the two-stage output filter capacitor bank (C10, C11).

[0028] The Schottky freewheeling diode (D3) has its anode grounded and its cathode connected to the node between the inductor (L1) and the switching output (PH) of the buck controller (U8). The diode is in an SMD package, typically SMA or SMB type, model B340A. Together, the diode (D3) and inductor (L1) form a low-current-ripple buck converter structure. At a 24V input, 12V output, and 330kHz switching frequency, the inductor current ripple is approximately 0.32A, only 21% of the average load current, far lower than the typical 30-50%.

[0029] The bootstrap capacitor (C7) is connected between the bootstrap terminal (BOOT) and the switching output terminal (PH) of the buck controller (U8) via the shortest trace, and has a capacitance of 100nF.

[0030] The dual-stage output filter capacitor bank (C10, C11) includes a large-capacity output capacitor (C10) and a small-capacity high-frequency filter capacitor (C11), positioned close to the output terminal of the inductor (L1). The large-capacity output capacitor (C10) is a 220μF vertically mounted capacitor, while the small-capacity high-frequency filter capacitor (C11) is a 100nF planar mounted capacitor. Their close arrangement forms a dual suppression structure for low-frequency ripple and high-frequency spikes. The large-capacity output capacitor (C10) primarily handles low-frequency load changes, providing energy reserves; the small-capacity high-frequency filter capacitor (C11) is used to suppress high-frequency switching noise. Together, they control the output ripple to the tens of mV level, reducing it by approximately 60-80% compared to the conventional 100-200mV.

[0031] The feedback voltage divider network (R30, R29) includes pull-up resistors (R30) and pull-down resistors (R29), connected between the feedback input (VSENSE) of the buck controller (U8). The pull-up resistor (R30) is 180kΩ, and the pull-down resistor (R29) is 20kΩ, configured to stabilize the output voltage at approximately 12V. The traces of the feedback voltage divider network (R30, R29) are routed away from the switching output (PH) of the buck controller (U8) to reduce high-frequency interference coupling and ensure accurate voltage sampling.

[0032] The multi-pin parallel output terminal (H2) includes three pins arranged in parallel, connected to a two-stage output filter capacitor bank (C10, C11) via wide traces. This configuration reduces contact impedance by approximately 60-70% and connection point temperature rise by approximately 10-15°C, improving the mechanical connection reliability under the vibration environment of a transformer foil winding machine.

[0033] The wiring between the buck controller (U8), inductor (L1), Schottky freewheeling diode (D3), and dual-stage output filter capacitor bank forms a minimum loop area layout to reduce parasitic inductance and electromagnetic radiation. This compact layout reduces the loop area by approximately 70% compared to a standard setup, and is expected to reduce radiation by approximately 8-12 dB, significantly reducing electromagnetic interference.

[0034] The working principle of this invention is as follows: The input power supply is first filtered by a two-stage input filter capacitor bank (C8, C9) to reduce input ripple. The high-side MOSFET inside the buck controller (U8) switches at a fixed frequency, sending the input energy to the inductor (L1) through the switch output terminal (PH). When the switch is on, the inductor current (L1) rises linearly, and energy is stored in the inductor; when the switch is off, the Schottky freewheeling diode (D3) conducts, providing a loop for the inductor current (L1), and the inductor current (L1) decreases linearly, transferring energy to the two-stage output filter capacitor bank (C10, C11) and the load. The output voltage is sent back to the feedback input terminal (VSENSE) of the buck controller (U8) through the feedback voltage divider network (R30, R29), compared with the internal reference voltage, and the controller adjusts the switching duty cycle to stabilize the output voltage at approximately 12V. The bootstrap capacitor (C7) provides a floating power supply for the high-side drive circuit inside the buck controller (U8). The two-stage output filter capacitor bank (C10, C11) filters the output voltage, eliminates switching ripple, and provides a clean DC power supply to the various components of the transformer foil winding machine control system.

[0035] The key points of this invention include: the copper layer area around the Schottky freewheeling diode (D3) should be as large as possible to enhance heat dissipation; the connection traces between the inductor (L1) and the Schottky freewheeling diode (D3) and the switch output terminal (PH) of the controller (U8) should be as short and wide as possible to form the minimum loop area; the high-frequency filter capacitor (C11) in the dual-stage output filter capacitor bank should be as close as possible to the load connection point to suppress high-frequency noise to the maximum extent; the feedback voltage divider network (R30, R29) should be far away from the main power switching node to reduce noise interference.

[0036] Furthermore, in practical applications, the step-down power supply module of this utility model can be finely adjusted according to the different requirements of the transformer foil winding machine control system: for applications requiring higher output current, the current rating of the inductor (L1) and the current capacity of the diode (D3) can be increased accordingly; for applications that particularly value low noise, the inductance value can be appropriately increased to 22μH or 33μH to further reduce current ripple; for environments with particularly severe vibration, the mechanical fixing method of the output terminal (H2) can be strengthened to improve vibration resistance.

[0037] The step-down power supply module of this invention solves the problems of severe electromagnetic interference, insufficient mechanical connection reliability and low energy efficiency faced by traditional power supplies in the control system of transformer foil winding machines. It provides a high-efficiency, low-noise and high-reliability power supply solution, which is particularly suitable for precision equipment such as transformer foil winding machines that require high-precision control and long-term stable operation.

[0038] The present invention is designed to evaluate the technical effect of the step-down power supply module of the transformer foil winding machine control system through the following experiment.

[0039] 1. The experiment employed a comparative testing method, comparing the proposed step-down power supply module with two traditional solutions (linear regulators and conventional switching power supplies). The test environment simulated the actual working conditions of a transformer foil winding machine control system, including vibration (random vibration of 5-50Hz) and long-term continuous operation (72-hour aging test). Data acquisition and analysis were performed using equipment such as a thermal imager, EMI receiver, power analyzer, and tension sensor testing system. Each test was repeated three times, and the average value was taken.

[0040] 2. Technical Effect Comparison Table

[0041]

[0042] 3. Verification Methods and Results

[0043] EMI Suppression Test: The electromagnetic interference levels of three schemes in the transformer foil winding machine control system were measured using an EMI receiver. In the 150kHz frequency band, the module's radiation was 68dBμV, 14dB lower than that of a conventional switching power supply. More importantly, when connected to the tension sensor and position encoder test system, the sensor signal fluctuations of this module were reduced by 17.5%, and the position encoder reading stability was improved by 22%, significantly reducing misreadings and downtime caused by EMI.

[0044] Energy conversion efficiency testing: The efficiency of three solutions under different load conditions was measured using a Yokogawa WT300E power analyzer. Under typical 24V input and 12V / 2A output conditions, this module achieved an efficiency of 88.5%, which is 10.2% higher than conventional switching power supplies and 38.7% higher than linear regulators. Long-term operation testing showed that this module reduced the temperature rise inside the control cabinet by 7.8℃ and reduced the cooling fan running time by 55%, which is crucial for extending the life of the cooling system and reducing the intake of metal dust.

[0045] Mechanical connection reliability testing: Three schemes were installed on a vibration test bench to simulate the working environment of a foil winding machine, and tested for 24 hours under random vibration conditions of 5-50Hz. After testing, the contact resistance of the multi-pin parallel output terminals of this module increased by only 0.8mΩ, while the conventional scheme increased by 2.5-3.7mΩ. Thermal imaging showed that the temperature rise of the contact terminals of this module under full load was only 7.3℃, which is 61-69% lower than that of the traditional scheme, significantly reducing the risk of contact point failure.

[0046] 4. Verification Conclusion

[0047] Through comprehensive testing and verification, the step-down power supply module of this invention achieves the goals of low interference and high efficiency. The multi-stage filtering network and large inductor configuration provide a clean power output, significantly improving sensor measurement accuracy. The multi-pin parallel terminal arrangement enhances mechanical connection reliability and adapts to the vibration environment of the foil winding machine. This, in turn, improves foil winding quality, reduces maintenance frequency, and lowers energy consumption and operating costs. This module is particularly suitable for transformer foil winding machine control systems requiring high precision and high reliability, and has broad application prospects.

Claims

1. A step-down power supply module for a transformer foil winding machine control system, characterized in that, include: Step-down controller (U8); A two-stage input filter capacitor bank, including a medium-capacity capacitor (C8) and a small-capacity high-frequency capacitor (C9), is arranged adjacent to the input terminal (VIN) of the buck controller (U8); An inductor (L1) is connected to the switching output (PH) of the buck controller (U8); A Schottky freewheeling diode (D3) is connected to a node between the inductor (L1) and the switching output terminal (PH) of the buck controller (U8). The bootstrap capacitor (C7) is connected between the bootstrap terminal (BOOT) and the switching output terminal (PH) of the buck controller (U8) via the shortest possible trace. A dual-stage output filter capacitor bank, including a large-capacity output capacitor (C10) and a small-capacity high-frequency filter capacitor (C11), is arranged close to the output terminal of the inductor (L1). The feedback voltage divider network, including pull-up resistors (R30) and pull-down resistors (R29), is connected between the output terminal and the feedback input terminal (VSENSE) of the buck controller (U8); The multi-pin parallel output terminal (H2) is connected to the dual-stage output filter capacitor bank via a wide trace.

2. The step-down power supply module of the transformer foil winding machine control system according to claim 1, characterized in that, In the dual-stage input filter capacitor bank, the medium-capacity capacitor (C8) is 10μF and the small-capacity high-frequency capacitor (C9) is 100nF.

3. The transformer foil winding machine control system step-down power supply module according to claim 1, characterized in that, The inductor (L1) is set with a large inductance value of 15μH, and together with the Schottky freewheeling diode (D3), they form a step-down conversion structure.

4. The step-down power supply module of the transformer foil winding machine control system according to claim 1, characterized in that, In the dual-stage output filter capacitor bank, the large-capacity output capacitor (C10) is 220μF vertically mounted, and the small-capacity high-frequency filter capacitor (C11) is 100nF planar mounted. The two are closely arranged to form a dual suppression structure for low-frequency ripple and high-frequency spikes.

5. The transformer foil winding machine control system step-down power supply module according to claim 1, characterized in that, The pull-up resistor (R30) of the feedback voltage divider network is 180kΩ, and the pull-down resistor (R29) is 20kΩ, configured to stabilize the output voltage at approximately 12V.

6. The step-down power supply module of the transformer foil winding machine control system according to claim 1, characterized in that, The multi-pin parallel output terminal (H2) includes three pins arranged in parallel to reduce contact resistance and heat concentration.

7. The transformer foil winding machine control system step-down power supply module according to claim 1, characterized in that, The feedback voltage divider network is located away from the switching output (PH) of the buck controller (U8) to reduce the coupling of high-frequency interference.

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