Description

1. Product Overview

Alstom EPIC Ⅲ EP3-E-4-A is a dedicated AVC automatic voltage controller for electrostatic precipitators (ESP) under the EPIC III (Electrostatic Precipitator Integrated Control) series. It serves as the core master control unit for transformer rectifier (TR) sets, specially designed to manage operating conditions of high-voltage ESP electric fields. Based on built-in SCR thyristor phase-shift voltage regulation algorithms, it dynamically adjusts secondary voltage and current of electric fields, adaptively captures spark flashovers and quickly restores power supply to electric fields, maximizing dust collection efficiency while reducing overall energy consumption.

Equipped with 4-channel analog signal acquisition inputs supporting standard 0~10V and 4~20mA industrial signals, it integrates a local keypad operation panel and LED status indicators. Compatible with dual communication links of RS485 and Ethernet, it can connect to upper-level ProMo/GE PRC centralized monitoring systems. Adopting an all-metal sealed enclosure and wide-temperature industrial hardware design, it features complete multi-level protection against electrical short circuit, overcurrent, overheating and high-voltage flashover. It is widely applied in flue gas dust removal projects of thermal power, steel, cement and waste incineration industries, commonly used for spare replacement of old ESP control cabinets, automation upgrading of dust removal systems and supporting capacity expansion of multi-electric-field dust removal devices.

2. Hardware Structure and Composition

2.1 4-Channel Analog Signal Acquisition & Processing Unit

It integrates 4 independent isolated analog input channels, corresponding to four key signals: primary current of rectifier transformer, secondary high voltage of electric field, secondary current and flue gas opacity feedback. Each channel adopts 16-bit high-precision analog-to-digital conversion, compatible with two signal formats: 0~10V voltage and 4~20mA current. Built-in independent signal filtering and isolation circuits for each channel filter harmonic interference from on-site frequency converters and high-voltage cables, and transmit collected data to the main control computing unit in real time to provide accurate raw data for spark identification and voltage regulation calculation. Terminals accept stranded wires (0.5~2.5mm²) and solid wires (0.5~4.0mm²) with vibration-resistant anti-loosening crimping, adapting to long-term vibration conditions in power plants and metallurgical plants.

2.2 Thyristor Phase-Shift Voltage Regulation Main Control Computing Unit

A high-speed microprocessor core is embedded with dedicated ESP spark identification control algorithms to real-time identify flashover and arc faults in electric fields, automatically adjust SCR thyristor firing angles, and dynamically balance corona power and flashover frequency. Large-capacity power-fail non-volatile memory stores more than 300 groups of spark records, voltage-current operating curves and fault alarm logs, with historical data and setting parameters permanently retained after power loss. Integrated hardware watchdog, over-temperature and over-current monitoring circuits immediately block thyristor output, latch fault codes and trigger local audible and visual alarms upon hardware abnormalities, while pushing fault messages to upper systems synchronously to prevent accidents such as high-voltage electric field breakdown and rectifier transformer burnout.

2.3 HMI & Multi-protocol Communication Unit

The front panel integrates digital keys and LED digital display windows, supporting on-site tuning of parameters such as spark recovery rate, upper voltage limit, current threshold and protection delay without upper software. Two independent communication ports are onboard: 10/100M adaptive RJ45 Ethernet and RS485 serial bus, supporting Modbus RTU/TCP industrial protocols. It can operate independently as a single unit or be daisy-chained with multiple EP3-E-4-A controllers to realize centralized remote monitoring, batch parameter distribution and proactive fault uploading of all factory ESP equipment.

2.4 Rack-mounted Metal Enclosure Mounting & Protection Unit

The integrated aluminum alloy sealed enclosure is equipped with strip convection heat dissipation grilles on both sides and standard rack mounting lugs for installation in 19-inch standard control cabinets. Integrated dedicated grounding contacts on the enclosure realize full-unit shield grounding when mounted on grounded cabinets to suppress common-mode electromagnetic interference from high-voltage electric fields. Strong and weak current wiring areas are physically separated. The EPIC III series maintains full backward compatibility in hardware and software, enabling direct on-site replacement of old EP3 series dust removal control modules without large-scale modification and reuse of original rectifier transformers and sensor wiring.

EP3-E-4-A (2).jpg

EP3-E-4-A (1).jpg

EP3-E-4-A (3).jpg

3. Technical Specifications

3.1 Electrical Specifications

Operating Power Supply: 110/220VAC 50/60Hz, typical power consumption 18W
Analog Acquisition Channels: 4 isolated AI channels, 16-bit resolution, supports 0~10V / 4~20mA
Control Output: SCR thyristor phase-shift trigger output, voltage regulation response speed ≤10ms
Spark Detection: High-speed flashover identification, spark recovery rate adjustable from 0.1~10s
Communication Interfaces: 10/100M adaptive Ethernet, RS485 (Modbus RTU)
Compatible Cable Specifications: Solid wire 0.5~4.0mm², stranded wire 0.5~2.5mm²
Dielectric Withstand Test: 2000VAC for input loops

3.2 Environmental Specifications

Operating Temperature: -10℃ ~ +60℃; Storage & Transportation Temperature: -40℃ ~ +85℃
Relative Humidity: 5%~95% RH, non-condensing, free of corrosive dust and acid flue gas
EMC Compliance: EN 61000-6-2 Industrial Class A anti-interference standard, suitable for strong electromagnetic environments of high-voltage dust removal
Protection Class: IP20 for enclosure; only for installation inside enclosed ventilated industrial control cabinets

3.3 Mechanical Specifications

Mounting Method: Embedded mounting for 19-inch standard racks
Overall Dimensions: W 240mm × H 180mm × D 120mm
Net Weight: Approx. 1.45kg
Enclosure Material: Aluminum alloy sealed heat dissipation housing
Optional Accessories: High-voltage rectifier transformer, 4~20mA opacity transmitter, industrial shielded network cable, rack mounting rail, upper-level ProMo monitoring configuration software

4. Product Functions and Features

Adaptive Spark Closed-loop Voltage Regulation Algorithm Balances Dust Removal Efficiency and Equipment Safety

It real-time monitors spark and arc status of electric fields, automatically adjusts thyristor firing angles to maintain maximum corona power without continuous flashover, greatly improving dust capture efficiency. In case of severe arcing, power output is quickly reduced and locked to avoid insulation breakdown of high-voltage electrodes and rectifier transformers, adapting to complex flue gas conditions with high dust and high specific resistance.

4-channel Isolated High-precision Signal Acquisition Ensures Stable Measurement Under Distorted Grids

Four analog channels adopt independent electrical isolation to simultaneously collect primary and secondary electrical parameters and flue gas feedback signals, effectively isolating harmonic interference from high-voltage electric fields and frequency converters, delivering drift-free and jitter-free collected data to support accurate voltage regulation control.

Dual Operation Modes of Local Panel & Remote Access Balance Commissioning and Centralized Management

It supports on-site panel local parameter setting and fault viewing, as well as remote four-remote control, batch parameter modification and historical curve export via Ethernet/RS485 connected to factory-wide SCADA systems. A single upper computer can uniformly manage dozens of ESP controllers, significantly reducing on-site inspection workload.

Full-dimensional Multi-level Hardware Protection Prevents Major Equipment Failures of High-voltage Dust Removal

Integrated multi-layer software and hardware protection against overcurrent, overvoltage, overheating, continuous flashover, signal breakage and power phase loss locks voltage regulation output and stores fault records instantly upon faults. Maintenance personnel can quickly locate fault points of electric fields, sensors and rectifier transformers to shorten downtime maintenance duration.

Industrial Wide-temperature Sealed Metal Design Enables Long-term Stable Operation in Harsh Plant Conditions

The aluminum alloy heat dissipation housing with fully isolated signal circuits withstands high temperature, heavy dust and strong electromagnetic interference in power plant and metallurgical plant environments. The fanless natural convection heat dissipation structure eliminates consumable fan components, enabling long-term continuous maintenance-free operation for 24/7 dust removal in power plants.

Standardized Compatible Architecture Simplifies Spare Replacement and System Capacity Expansion

Fully compatible with all EPIC III series dust removal controllers, old modules of the same specification can be directly replaced on site without re-laying original sensors, rectifier transformers and communication lines. Multiple controllers support bus daisy-chaining for expansion, and newly added dust removal electric fields do not require reconstruction of the entire monitoring network, lowering renovation and expansion costs.

5. Applicable Working Conditions and Application Scenarios

Automatic voltage regulation and spark suppression control projects for high-voltage rectifier transformers in flue gas electrostatic dust removal systems of thermal power plants and waste incineration power plants.
Closed-loop regulation supporting systems linked with flue gas opacity for ESP devices in production lines of steel smelting and cement building materials.
Renovation projects of automatic high-voltage electric field voltage stabilization and remote fault monitoring for tail gas dust removal complete sets of chemical and petrochemical plants.
Intelligent remote monitoring and control scenarios for new construction and upgrading of municipal waste incineration and hazardous waste disposal plant dust removal systems.
Spare replacement of aging faulty Alstom EPIC series ESP controllers and intelligent remote monitoring transformation projects for dust removal systems.

Alstom EPIC Ⅲ EP3-E-4-A AVC Automatic Voltage Controller