This case note introduces how ABB's ACS 1000 variable speed drives helped Helsinki Energy improve the efficiency of its CHP power plant.
The document presents a case study of Helsinki Energy’s combined heat‑and‑power (CHP) plant, where four ABB ACS 1000 variable speed drives (each rated at 4500 kW) replaced wound‑rotor motors with slip‑recovery control. The upgrade aimed to lower maintenance costs and boost overall plant efficiency by allowing the feed‑water pumps to operate at variable speed.
Benefits highlighted include higher plant efficiency, reduced maintenance of throttling valves, and additional savings from softer start‑up behavior and lower fault currents. ABB supplied split‑cabinet drives that could be transported by the existing elevator, and the drives can connect via common field‑buses and support a power range of 315 kW to 2 MW with multiple output voltage options.
| Drive rating | 4500 kW |
|---|---|
| Power range | 315 kW – 2 MW |
| Output voltage | 2.3‑4.16 kV (optional 6.0‑6.6 kV) |
| Motor type | Induction motor |
| Inverter type | Three‑level Voltage Source Inverter (VSI) |
The drives increased plant efficiency, reduced maintenance costs of feed‑water throttling valves, and provided soft‑starter operation with lower fault currents.
ABB designed split‑cabinet units that could be lifted by the plant’s elevator, avoiding major building modifications.
The ACS 1000 can operate from 315 kW up to 2 MW.
It is intended for use with induction motors.