OP­TIPUMP – En­er­gy-ef­fi­cient SiC pump dri­ves, FHNW School of Engineering and Environment

Technology

• Silicon carbide (SiC)

• Power electronics

• Frequency converters

• Electric drive systems

• Energy efficiency

Background

Electric drive systems are often operated at partial load, where their efficiency is relatively low. OPTIPUMP investigates the efficiency benefits of SiC-based drive systems, focusing on the application-relevant partial-load range.

A commercial pump drive using conventional IGBT technology serves as the reference system. It is compared with a SiC MOSFET-based drive system developed at FHNW.

1. Development of a 5.5 kW frequency converter using SiC MOSFETs with specifications comparable to the commercial IGBT reference system.

2. Comparison of both systems under realistic operating conditions in terms of efficiency and losses (measured from the grid connection to the motor shaft).

3. Investigation of how semiconductor technology, switching frequency and motor-side filters affect overall energy efficiency.

4. Estimation of the annual global energy-saving potential of SiC-based pump drives.

Results

The SiC frequency converter developed at FHNW was tested together with a custom-developed low-loss sine-wave filter on a dedicated test bench. Compared with the IGBT reference system, the SiC system improves efficiency by 1.3 percentage points at nominal load and up to 10 percentage points at partial load. The highest efficiency was achieved at a switching frequency of 8 kHz.

The global energy-saving potential of SiC pump drives is estimated at 17–25 TWh per year.

In addition, a freely available calculation tool was developed. Users can enter their own load profiles and efficiency data to compare the energy consumption, energy costs and potential savings of different drive systems. The source code is openly available.

Open the OPTIPUMP final report on ARAMIS

Schlussbericht OPTIPUMP auf ARAMIS öffnen