ALSTOM ALSPA series frequency converter

ALSPA Transmission Full Series: Industrial Drive Solutions from Low Voltage to 100MW

In the field of industrial transmission, the reliability, efficiency, and adaptability of the drive system directly determine the production capacity and energy consumption of the production line. ALSTOM (now under GE Power Conversion), with over 100 years of experience in transmission power devices, has been recognized as one of the industry leaders. Its ALSPA transmission product line covers from simple offline low-voltage inverters of 0.25kW to engineering customized drive systems of over 100MW. This article systematically reviews the product architecture, core controller technology, typical application scenarios, and global service system of the ALSPA transmission series from the perspective of a technical engineer, providing in-depth reference for professionals engaged in drive system selection, integration, and operation.

The history and technological accumulation of ALSTOM's transmission business

The foundation of ALSTOM in the field of transmission can be traced back to the early stages of electrification over a century ago. The company not only has advanced manufacturing factories in France, Germany, the United Kingdom, and the United States, but more importantly, ALSTOM integrates its own transmission products into other equipment and systems it manufactures (such as ship propulsion, traction power supply, and generator sets), thus accumulating decades of real user side operating experience. This dual mode of "self use+export" ensures that the product fully considers thermal stress, harmonics, impact loads, and maintenance convenience in actual working conditions during the design phase.

In recent years, ALSTOM has launched multiple innovative achievements in the field of driving solutions, including:

Marine pod type electric propulsion system (motor installed under the cabin)

19MVA, 4.2kV IGBT propulsion converter and motor for naval warships

100MVA inverter for pumped storage power station

15MVA, 50Hz three-phase to single-phase traction power converter equipped with active energy management

The technological accumulation of these high-end projects is directly fed back into the ALSPA standard products and engineering driver series, enabling industrial users to enjoy topology structures and control algorithms validated under extreme working conditions.

Overview of the full spectrum of ALSPA transmission product line

The ALSPA series is not a single product, but a complete family that covers voltage levels, power ranges, and motor types. According to the degree of standardization, it can be divided into two categories: standard equipment and engineering customized equipment.

2.1 Standard Equipment

Standard equipment refers to catalog selection products with short delivery cycles and mature spare parts support.

DC transmission: power range from 7.5kW to 25MW, customized solutions are available for 750kW and above. DC transmission is still suitable for applications that require high overload capacity and four quadrant operation, such as steel mills and mine hoists.

Low voltage AC drive (induction motor): 0.25kVA to 5MVA, suitable for common low voltage power grids such as 400V/690V. Typical applications include fans, pumps, compressors, extruders, and mixers.

Medium voltage AC drive (induction motor): 300kVA to 25MVA, output can directly reach 10kV without the need for a transformer. Suitable for medium voltage motors such as cement mills, crushers, large conveyors, and mining fans.

Synchronous motor or wound rotor motor drive: 0.25kW to 100MVA, supporting excitation control and slip ring control, used for high-power rolling mills, ship propulsion, wind tunnel drive, etc.

2.2 Engineering customized equipment

For special requirements beyond the standard product range, ALSTOM provides fully engineered drive systems, such as:

High power DC power supply and high current rectification system (used for electrolysis and arc furnaces), with a bridge arm of over 60000A per 12 pulses, based on direct water-cooled thyristor cabinets. A typical aluminum electrolysis factory configuration is 4 × 60kA or 5 × 70kA, 1000Vdc.

Static frequency converter (up to 100MVA), used for large magnet power supply (such as fusion research institutions) or AC/AC frequency conversion (three-phase/single-phase, 50Hz/16.7Hz, etc.), has provided a turnkey system for German railways from 110kV/50Hz to 25kV/16.7Hz.

Power Semiconductor and Control Platform: PEC Controller Family

In order to meet the control needs from simple single machine to complex multi transmission, ALSTOM has developed a new family of power electronic controllers (PEC). This platform covers from single card units (standard or advanced versions) to modular rack mounted systems, and can adapt to all ALSPA transmission products.

3.1 Advantages of Unified Architecture

The PEC family adopts a single architecture, and all core functions are implemented through common technologies:

Processor: Pentium class 32-bit floating-point arithmetic processor (optional DSP for some enhanced versions).

Operating System: A unified real-time operating system used for both transmission and automation control.