Commercial self-service terminals and unattended retail equipment serve as core carriers in new retail, smart city and public service scenarios, covering vending machines, self-service coffee machines, smart parcel lockers, unmanned convenience stores, lottery terminals, government self-service kiosks, ticketing machines and shared power bank cabinets. Modules such as static elimination units, ozone disinfection assemblies, high-pressure lens dust removal systems, high-voltage driving mechanisms and cold-cathode lighting all rely on dedicated high-voltage power supplies to deliver stable high-voltage output. These realize critical functions including surface static removal for goods, ozone sterilization inside cabinets, electrostatic dust cleaning for scanning lenses, cold-light driving and electrostatic fresh-keeping adsorption. As essential components ensuring 7×24-hour unattended stable operation, their integration level, long-term reliability, environmental adaptability, low-power performance, safety protection and intelligent management directly determine continuous operating capability, maintenance costs, user experience and even the commercial viability of unattended retail projects. Scenarios for commercial self-service terminals raise differentiated technical requirements completely different from standard industrial power supplies, presenting eight core challenges. First, extreme long service life and high reliability under unattended operation. Deployed in communities, business districts, subway stations and scenic spots, such equipment runs continuously for more than 8,760 hours annually. Decentralized large-scale deployment leads to extremely high on-site maintenance costs. Power supply failures cause downtime, jamming, disinfection failure and scanning recognition errors, resulting in revenue loss and brand damage. The required MTBF is ≥1×10⁵ hours with a design life ≥10 years. Built-in fault tolerance and automatic recovery ensure stable operation against grid fluctuations, abnormal loads and environmental changes without manual intervention, greatly reducing maintenance frequency. Second, ultra-high integration and miniaturization. Internal space in self-service devices is highly compact, housing storage channels, refrigeration, control and payment systems. Reserved space for high-voltage modules is limited to only a few cubic centimeters. Multiple independent high-voltage outputs for static elimination, disinfection and dust removal are required. Power supplies must integrate 2–8 isolated channels within tiny volumes, with each single channel ≤5 cm³ and overall power density ≥250 W/in³, enabling embedded installation inside gaps, storage channels and scanning assemblies without occupying core functional space. Third, wide grid adaptability and ultra-low power consumption. Deployed nationwide and globally, equipment encounters severe grid fluctuations ranging from 60% to 140% of rated voltage in remote or aging areas, including surges, dips and short interruptions. Input coverage must support 85 VAC–265 VAC worldwide with 200 ms ride-through capability against momentary power loss. Since electricity costs dominate operational expenses—especially for refrigerated vending machines—the peak efficiency must reach ≥92%, standby power ≤0.5 W and static power ≤3 mW to minimize overall energy consumption. Fourth, full-scenario environmental adaptability. Operating environments vary drastically from cold outdoor cabinets (−30 ℃) to high-temperature/humidity convenience stores (+60 ℃), high-altitude scenic areas and coastal salt-fog zones. Equipment must withstand temperatures from −30 ℃ to +60 ℃, humidity from 10% to 95% RH, heavy dust, salt spray, UV radiation and pest exposure. High-level protection ≥IP65 ensures stable performance unaffected by harsh conditions. Fifth, strict safety protection and public safety compliance. Accessible to all age groups including children and the elderly, these devices involve frequent human contact with doors, pick-up openings and touchscreens. Food-related applications enforce strict limits on ozone concentration and static residue. Some units operate in flammable zones such as gas stations. Power supplies require non-bypass multi-layer safety mechanisms: double insulation with ≥4,000 VAC isolation, output short-circuit current limited ≤50 μA, precise ozone dosage control complying with GB 28235, and flame-retardant explosion-proof construction to prevent electric shock, fire and excessive ozone leakage. Sixth, ultra-low electromagnetic interference and full EMC compliance. Integrated scanning modules, payment systems, 4G/5G communication, touch controls and variable-frequency refrigeration are highly sensitive to EMI. Switch noise and radiation from high-voltage units may cause scanning failure, communication interruption, touch malfunction and system errors. Conducted and radiated emissions must fully comply with GB/T 9254 and GB/T 17626 while maintaining strong immunity to internal interference from motors and RF modules. Seventh, intelligent control and IoT integration. Digitalized unattended operation requires seamless cloud connectivity for remote parameter adjustment, real-time status monitoring, early fault warning and automatic maintenance dispatching. Power supplies must adapt dynamically according to operational modes, environmental conditions and disinfection demands to achieve fully intelligent unmanned management. Eighth, low-cost mass production with high consistency. As large-volume consumer commercial products, cost sensitivity is critical while cross-batch performance uniformity must be guaranteed. Simplified topologies, fewer components, streamlined manufacturing and standardized testing ensure cost-effective scalable production without compromising reliability. Targeting these core requirements, the methodology establishes a full-process technical framework covering high-density multi-channel topology design, unattended long-lifetime optimization, full-environment robustness, low-energy architecture and IoT intelligent management. It supports vending machines, coffee terminals, unmanned stores, government kiosks and parcel lockers, providing standardized guidelines for domestic core-component upgrading and localization. The universal technical architecture adopts a two-stage distributed solution: **centralized regulated bus + distributed miniature POL high-voltage modules**. The front stage converts wide fluctuating grid input into a stable low-voltage DC bus to resolve grid compatibility and low standby issues. The rear miniature POL modules independently generate precision-adjustable high voltages for each functional node. Each compact module (3–5 cm³) embeds directly inside storage channels, scanning units and disinfection chambers, minimizing high-voltage wiring loss and crosstalk. Fully solid-state construction with extreme component derating delivers a 10+ year maintenance-free lifespan for unattended deployment. The design follows eight core principles: 1. Highly integrated multi-channel topology - Front wide-range regulated bus with APFC + isolated flyback achieves 85–265 VAC universal input, PF ≥0.98, THD ≤10%, peak efficiency ≥92%, stable 12 V/24 V DC output and standby power ≤0.5 W. - Rear miniature POL modules use compact high-frequency push–pull inverters with voltage multipliers, limited to ≤15 components, packaged within 10×10×30 mm (≤3 cm³, ≤20 g). Switching frequency raised to 200–300 kHz shrinks magnetic components drastically. Output adjustable 3–15 kV with stability ≤±1%, supporting constant voltage, constant current and pulse modes for static elimination, ozone disinfection and dust removal. - Modular bus structure enables plug-and-play expansion of 2–8 channels with independent addressing and communication for customized equipment configurations. 2. Long-lifetime high-reliability design for unattended scenarios - Extreme component derating: voltage stress ≤40%, current ≤30%, temperature ≤50%, capacitor stress ≤50%, flux density ≤25% saturation to extend lifespan and ensure MTBF ≥1×10⁵ hours and ≥10-year service life. - Fully solid-state construction with no fans, relays, electrolytic capacitors or mechanical wear parts; only long-life ceramic and film capacitors for maintenance-free operation. - Redundant architecture: dual redundant front bus and isolated rear channels prevent single-point failure; critical reference, sampling and control circuits support seamless switchover. - Dual hardware–software protection with sub-1 μs overvoltage/overcurrent/short-circuit/overtemperature response; automatic recovery for transient grid faults; graceful derating and early warnings for permanent faults; watchdog reset prevents system lockup. 3. Full-scenario environmental robustness - Extended-temperature components (−40 ℃ to +85 ℃) guarantee stable startup from −30 ℃ to +60 ℃ with output drift ≤±1%; adaptive temperature compensation suppresses parameter drift; overtemperature derating and shutdown protect against overheating. - Full sealing: front metal enclosure ≥IP65; rear epoxy potting ≥IP68; conformal coating, gold-plated terminals, salt-fog resistance, UV-proof casing and anti-pest encapsulation ensure durability in harsh outdoor and industrial environments. - Surge immunity up to ±4 kV and EFT ±2 kV; 200 ms hold-up time against short power interruptions; comprehensive over/under voltage and reverse polarity protection. - Full EMI suppression via soft switching, metal shielding ≥60 dB and multi-stage filtering; EMC immunity meets GB/T 17626 Level 4. 4. Ultra-low power consumption and energy optimization - System-wide high efficiency: front ≥92% peak / ≥85% light load; rear POL ≥90% efficiency. - Three-level intelligent power modes: full operation for daily use; low-static standby (<3 mW) during low-traffic periods; deep hibernation (<0.5 W standby) with only wake-up circuits active. - Adaptive auto-start using human detection, door sensors and channel activity; automatic adjustment of disinfection/static elimination strength based on humidity, bacteria levels and static conditions. - APFC reduces reactive power loss and maintains optimal efficiency during grid fluctuations. 5. Comprehensive safety and compliance - Nanosecond current limiting restricts all high-voltage outputs ≤50 μA to eliminate electric shock risks even upon direct human contact; instant arc suppression prevents fire hazards. - Double reinforced insulation ≥4,000 VAC isolation; triple-insulated transformer windings; fully potted high-voltage sections isolate exposed user surfaces. - Precision ozone closed-loop control ensures residual concentration ≤0.1 mg/m³ complying with GB 28235; interlock safety cuts high voltage instantly when cabinet doors open. - V-0 flame-retardant materials throughout; intrinsically safe design for explosive environments; compliance with GB 4706.1, GB 4943.1 and international CE/UL certifications. 6. Miniaturization and mass-production consistency - High-frequency miniaturization shrinks magnetic components; multi-layer PCB and double-sided mounting maximize density; single-channel volume ≤3 cm³ with power density ≥250 W/in³. - Standardized modular interfaces ensure interchangeability across product lines; fully automated SMT and potting improve yield. - General mass-market components with sufficient parameter margins; standardized automated testing guarantees batch deviation ≤±0.5%. 7. Intelligent control and IoT connectivity - Rich interfaces including RS485, CAN, Ethernet, Wi-Fi and 4G supporting Modbus/MQTT for remote tuning, real-time telemetry, fault uploading, energy logging and OTA upgrades. - Built-in health assessment and AI fault diagnosis predict aging and failures to enable predictive maintenance and automatic work-order dispatching. - Sensor fusion with temperature/humidity, ozone, static and human presence enables fully adaptive unmanned operation. 8. Food-safety and commercial regulatory compliance - All food-contact materials comply with GB 4806; sealed high-voltage assemblies prevent contamination; ozone dosage strictly controlled for food safety. - Complete traceable logs for disinfection and operation records meet regulatory audit requirements for public commercial catering and unattended retail. In summary, this full-process framework resolves traditional limitations including low integration, large volume, high maintenance cost and poor unattended reliability. Distributed miniature modules achieve ultra-compact single-channel sizing and flexible multi-channel expansion. All-solid-state derated design delivers 10⁵-hour reliability and 10-year maintenance-free lifespan. Adaptive low-power modes reduce standby consumption below 0.5 W. Comprehensive safety architecture protects users and food quality, while cloud-based intelligence enables fully unmanned predictive operation. The methodology widely supports vending, coffee, parcel, government and shared equipment applications, empowering domestic core-component localization and performance upgrading in unattended commercial retail infrastructure.