Petrochemical & Refining Power Solutions
Rectifier & Phase-Shifting Transformers, Flameproof Distribution
Overview
QDTB® provides specialized power equipment for petrochemical plants and refineries, where power quality and process safety are non-negotiable. Our rectifier transformers (12/18/24-pulse) feed electrolysis, electroplating and DC process loads while phase-shifting windings cancel harmonic currents at source; our isolation and control transformers, together with flameproof and corrosion-resistant switchgear, deliver safe, stable power distribution for hazardous areas. Every package is engineered for continuous 24/7 process duty, with the harmonic mitigation and fault isolation that keep refining and chemical processes running safely.
Multi-Pulse Rectifier Transformers
12/18/24-pulse phase-shifting rectifier transformers cancel 5th/7th/11th/13th harmonics at source for clean DC process power.
Explosion-Proof & Corrosion-Resistant
Flameproof transformers and anti-corrosion cabinets for Zone 1/Zone 2 hazardous areas and corrosive refinery atmospheres.
Precision Isolation & Control
Isolation and control transformers provide galvanic separation and clean control power for DCS, PLC and instrumentation systems.
Process-Duty Reliability
Continuous-duty thermal ratings, high short-circuit withstand and harmonic-tolerant winding design for 24/7 petrochemical operation.
Petrochemical Power System Calculator
Size and configure a high-reliability dual-source power distribution system for continuous petrochemical processes - redundancy level, explosion-proof equipment, BOM and single-line diagram.
Industry Context & Operational Characteristics
Petrochemical and refining processes rely on high-power DC loads (electrolysis, electroplating) and dense motor-driven process trains, making harmonic distortion and hazardous-area safety the two dominant electrical challenges. Rectifier transformers with phase-shifting windings are the standard solution because they cancel harmonic currents at source, while flameproof and corrosion-resistant equipment is required wherever flammable gases, vapors or corrosive atmospheres are present. Power continuity is critical: any outage can halt a continuous process with severe cost, so reliability and fault isolation are the top selection criteria.
Key Operational Challenges
Power Distribution Architecture
Plant Substation → Rectifier/Phase-Shifting Transformer → Converter/Electrolyzer → DC Process Load; with Isolation/Control Transformers feeding DCS/PLC and Hazardous-Area LV Distribution
Core Equipment Selection
Rectifier & Phase-Shifting Transformers
Recommended Model: SFFZ rectifier transformers (12/18/24-pulse, special-isolation-control-transformers)
Core Configuration & Advantages
- Phase-shifting windings cancel 5th/7th/11th/13th harmonics at source
- High-current, low-voltage secondary design for electrolysis and plating duty
- Enhanced thermal and short-circuit withstand for continuous rectifier loading
- Custom pulse number and vector group to match converter topology
Applications: Electrolysis, chlor-alkali, electroplating and electro-winning DC processes.
Flameproof & Isolation Transformers
Recommended Model: KBSG Flameproof Transformers / ZGS Isolation Transformers
Core Configuration & Advantages
- Explosion-proof enclosures for Zone 1 / Zone 2 hazardous areas
- Galvanic isolation protects DCS, PLC and instrumentation circuits
- Corrosion-resistant coatings for refinery and coastal atmospheres
- Low leakage current and shielding for clean control power
Applications: Hazardous-area distribution and sensitive control/instrumentation power.
Harmonic & Current-Limiting Reactors
Recommended Model: Current Limiting Reactors / DC Smoothing Reactors (reactors)
Core Configuration & Advantages
- Limit short-circuit current to protect downstream switchgear and converters
- Smooth DC ripple for stable electrolysis and plating quality
- Damp harmonic resonance with capacitor banks, protecting the plant network
- Custom inductance and current rating per converter design
Applications: DC smoothing and network harmonic/SC mitigation in process plants.
Switchgear & Substation Selection
Medium-Voltage Process Switchgear
KYN28/KYN61 medium-voltage switchgear provide reliable switching, protection and metering for refinery substations, with arc-resistant options for critical process feeders.
Hazardous-Area LV Distribution
Functional LV switchgear and flameproof distribution panels feed process motors, heaters and instrumentation in classified areas with explosion-safe construction.
Harmonic Filter & Compensation
Reactor and capacitor banks damp harmonic resonance and correct power factor, keeping the plant network within IEEE 519 limits.
Petrochemical Scenario Customized Enhancement
Pulse-Number Selection
12/18/24-pulse winding design matched to converter and grid harmonic limits
Explosion-Proof Rating
Ex-rated flameproof enclosures per IEC 60079 for the plant hazardous-area class
Anti-Corrosion Treatment
Multi-layer coatings and stainless hardware for corrosive refinery atmospheres
Harmonic Study Support
Transformer/reactor parameters sized from plant harmonic and SC studies
Redundant / N+1 Configurations
Parallel and standby transformer arrangements for continuous process availability
Power Quality Optimization
Rectifier and converter loads in petrochemical plants generate high-magnitude harmonic currents that distort voltage and can excite resonance with capacitor banks. Multi-pulse phase-shifting rectifier transformers plus detuned reactors suppress harmonics at source, keeping the plant network within IEEE 519 limits and protecting process equipment.
Key Benefits
Harmonic Suppression at Source
Multi-pulse phase-shifting rectifier transformers cancel harmonics where they are generated
Hazardous-Area Safety
Flameproof and corrosion-resistant equipment for Zone 1/Zone 2 process areas
Clean Control Power
Isolation transformers protect DCS, PLC and instrumentation from disturbance
Continuous-Duty Reliability
Thermal and short-circuit ratings engineered for 24/7 process operation
Single-Source Integration
Transformers, reactors and switchgear sized together for a coherent plant network
Technical specifications
| Rectifier Pulse | 12 / 18 / 24-pulse phase-shifting |
| Capacity Range | Up to 20,000 kVA (rectifier duty) |
| Voltage Range | Up to 35 kV primary / DC output per process |
| Frequency | 50 Hz / 60 Hz |
| Protection | Flameproof (Ex) / corrosion-resistant enclosures |
| Harmonic Cancellation | 5th / 7th / 11th / 13th per pulse number |
| Insulation Class | F / H (155°C / 180°C) |
| Standards | IEC 60076 / IEC 61378 / GB 1094 |
Standards Compliance
Applications
Related Products
Explore QDTB® product lines available for this solution
Special/Isolation/Control Transformers
SFFZ rectifier and phase-shifting transformers plus flameproof KBSG units
Reactors
Current-limiting and DC smoothing reactors for harmonic and short-circuit control
High Voltage Switchgear
KYN28 / KYN61 medium-voltage switchgear for process plant distribution
Low Voltage Switchgear
Functional LV switchgear panels for motor and process control feeders
Why Choose QDTB® for Petrochemical & Refining Power Solutions
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