Industrial flue gas desulfurization, denitrification and dust removal form the core barrier for atmospheric pollution prevention, enabling ultra-low emissions in thermal power, steel, cement, coking and non-ferrous industries. High‑voltage power supplies serve as critical power cores for electrostatic precipitators, wet electrostatic precipitators, low‑temperature plasma denitrification units and high-frequency desulfurization equipment. Delivering high-power high-voltage output to electric fields and plasma reactors, they realize particle charging and adsorption, together with degradation and removal of SO₂, NOₓ and VOCs via high-voltage ionization. Their output power, conversion efficiency, spark suppression, long-term reliability and working-condition adaptability directly determine dust collection efficiency, pollutant removal performance and compliance with industrial ultra-low emission standards. Flue gas treatment demands extreme specifications in high power, high efficiency and high reliability across eight key dimensions. 1.High-power wide-range output capability. Large-scale electrostatic precipitators for thermal power and steel plants require single-unit power up to hundreds of kilowatts or even megawatts, with adjustable voltage from 40 kV to 100 kV. Designs support continuous 0–100 kV regulation, maximum single-unit output up to 2 MW and parallel expansion for mega-project demands, achieving conversion efficiency ≥95% to minimize operational energy consumption. 2.Advanced nanosecond spark control and adaptive operation. Flue gas temperature, humidity, dust concentration, resistivity and composition fluctuate dynamically with boiler load and fuel variation, easily triggering spark discharge, arcing and short circuits. Traditional power supplies suffer severe voltage drop and efficiency loss during flashover. High-performance solutions detect sparks within 1 μs and apply intelligent arc-extinguishing algorithms to maintain average voltage and peak purification efficiency, while automatically tuning parameters according to real-time flue gas characteristics for optimal desulfurization, denitrification and dust removal. 3.Extreme long-term reliability for uninterrupted annual operation. Industrial flue gas systems operate 24/7 throughout the year; power failures directly cause excessive emissions and heavy environmental penalties. Deployed in high-temperature, dusty and corrosive environments with difficult maintenance, power supplies require MTBF ≥1×10⁵ hours and design life ≥15 years, with outstanding resistance against corrosion, dust and thermal aging. 4.High power factor and ultra-low harmonic performance. High-power high-voltage systems represent strong nonlinear loads. Compliance with GB/T 14549 mandates power factor ≥0.99 and THD ≤3%, eliminating grid pollution and reducing reactive power loss for improved energy utilization. 5.Extreme environmental adaptability under harsh site conditions. Ambient temperatures range −30 ℃ to +60 ℃, while flue gas exceeds 120 ℃ with heavy dust, humidity and corrosive SO₂/NOₓ gases. IP54 protection and full three-proof construction guarantee stable long-term operation in aggressive industrial environments. 6.Low electromagnetic interference and full EMC compliance. High-frequency switching in megawatt power stages generates strong EMI, threatening on-site DCS, instruments and communication networks. Compliance with GB/T 17626 and GB/T 14598 ensures ultra-low conducted/radiated emissions and robust immunity against complex industrial interference. 7.Intelligent control and environmental compliance traceability. Real-time emission data uploading and tamper-proof recording are mandatory. Integrated Modbus, Profibus and OPC UA interfaces enable seamless linkage with plant DCS and online monitoring platforms, supporting remote tuning, real-time diagnostics, early fault warning and automatic optimization balancing emission compliance and energy consumption. 8.Energy-saving operation and strong grid adaptability. Under dual-carbon policies, strict energy management requires average efficiency ≥93% across 20%–100% load ranges. Stable performance is maintained during 70%–130% nominal grid voltage fluctuation, with built-in reactive power compensation to stabilize factory power grids and reduce overall electricity costs. This methodology establishes a complete technical framework covering high-power high-efficiency topology, intelligent spark suppression, full-condition adaptive optimization and long-life reliability engineering. It standardizes high-voltage power design for electrostatic precipitators, wet electric precipitators and plasma denitrification systems, accelerating domestic breakthroughs in core industrial flue gas treatment components. Targeting critical challenges in megawatt power delivery, ultra-high efficiency, precise spark control and extreme durability, the universal architecture adopts three-level three-phase APFC + full-bridge LLC resonant soft-switch inversion + fully digital intelligent flashover control, reinforced with full-condition adaptive tuning and three-proof environmental hardening. It overcomes traditional weaknesses including low efficiency, poor spark handling, weak working-condition adaptability and excessive energy consumption through eight standardized principles: 1.Megawatt-class high-efficiency topology optimized with three-level APFC and LLC resonance, achieving ≥95% conversion efficiency and scalable high-power output. 2.Ultra-fast nanosecond spark detection and adaptive arc suppression maintaining peak dust removal during frequent flashover events. 3.Full-flue-gas adaptive algorithm dynamically adjusting operational parameters to cope with variable temperature, humidity and dust characteristics. 4.Low-harmonic power quality design delivering power factor ≥0.99 and THD ≤3% for strict grid compliance. 5.Extreme component derating, redundant architecture and corrosion protection ensuring ≥15 years maintenance-free service life. 6.Full environmental hardening against high temperature, heavy dust and acidic corrosion at industrial flue gas sites. 7.End-to-end EMC optimization minimizing EMI interference with on-site automation and instrumentation systems. 8.Industry-standard intelligent communication and traceable data management fully aligned with national environmental supervision and ultra-low emission requirements.