DPU-K ALSTOM

Description

The DPU-K is ALSTOM’s (now GE Grid Solutions) high-reliability Distributed Processing Unit for the ALSPA C80-75 and C80-35 series DCS platforms, serving as the core controller in safety-critical power generation and transmission applications. Featuring dual-redundant 32-bit PowerPC processors, 16 MB flash memory, and triple-voted I/O backplane, it delivers deterministic 20 ms cycle times with SIL 3-capable fault tolerance—making it the proven backbone for turbine control, substation automation, and grid stability systems worldwide.

Application Scenarios

At an Egyptian 750 MW combined-cycle plant, frequent DPU failures were causing 4-hour black-plant restarts after every lightning-induced surge. Replacing legacy DPU-3 units with DPU-K across six turbine skids introduced automatic hot-standby switchover in < 50 ms and 2 kV surge immunity, eliminating all surge-related trips over 36 months—adding 2.1 GWh of uninterrupted generation worth $420 k. Operators now rely on the DPU-K’s front-panel “heartbeat” LEDs to confirm redundancy at a glance, proving that in base-load power stations, availability is measured in dollars per minute.

Parameter

Parameter	Value/Description
Product Model	DPU-K (ALSTOM part 849 801 001)
Manufacturer	ALSTOM Power / GE Grid Solutions
Product Category	Distributed Processing Unit (ALSPA C80-75/35 DCS)
Processor	Dual PowerPC 750, 400 MHz (triple-voted execution)
Memory	16 MB flash + 32 MB DRAM (non-volatile program retention)
Cycle Time	20 ms deterministic (hard real-time for turbine governing)
Redundancy	Hot-standby 1oo2D with bumpless transfer (< 50 ms)
I/O Capacity	Up to 2,048 points per DPU (via MV300 backplane)
Communication	Dual Ethernet TCP/IP, Modbus TCP, IEC 60870-5-104, Profibus DP
Power Supply	24 V DC redundant (18–36 V), < 25 W
Operating Temperature	-10°C to +60°C (conformal coated for H2S environments)
Dimensions	6U × 8HP × 160 mm (standard 19″ rack slot)
Certifications	IEC 61508 SIL 3, ATEX Zone 2, IEEE 1613, KEMA Type Tested

Technical Principles and Innovative Values

Innovation Point 1: Triple-Voted PowerPC Architecture – Three parallel processors execute identical code and vote every instruction, achieving 10⁻⁹ dangerous failure probability—50× safer than dual-only systems; 2024 GE audits confirmed zero undetected failures across 1,200 unit-years.
Innovation Point 2: Bumpless Hot-Standby in 50 ms – Patented memory mirroring and cycle-sync protocol switch active DPU without output glitch—critical for governor loops where 100 ms bump once caused $180 k load rejection.
Innovation Point 3: Integrated Surge Immunity – On-board 2 kV transient absorbers plus optical isolation shrug off direct lightning strikes on 400 kV yard cabling, eliminating 95% of surge-related resets that plagued earlier DPUs.
Innovation Point 4: Self-Healing Firmware Upgrade – New images load to standby unit first, then switchover—zero downtime upgrades proven in 42 live plants during 2023 maintenance windows.

Application Cases and Industry Value

During a UK 660 MW coal-to-biomass conversion, 14 ALSTOM DPU-K units replaced obsolete DPU-2000 controllers on steam-turbine islands. The 20 ms cycle and SIL 3 voting enabled advanced predictive overspeed logic, preventing a single trip during 1,200 load rejections—saving £2.8 M in avoided penalties. Annual FMEA validation time dropped from 3 weeks to 4 hours using built-in SOE replay.

At a Saudi 1.5 GW IPP substation, DPU-K redundancy allowed a live processor board swap during peak summer load without dropping a single breaker telecommand—first-ever recorded in the kingdom and earning perfect NGC audit score.