The Alfen Battery Energy Storage Systems (BESS) balances energy supply and demand and helps to avoid heavy infrastructure investments in the power grid. Self-generated energy can be sold at the most profitable moments, allowing the development of autonomous electricity networks based on solar or wind energy. We spoke with René van Wesenbeeck, Principal Architect at Alfen, about developing and testing such a system and the collaboration with CN Rood.
Two main components of a BESS
René van Wesenbeeck: "A BESS consists of batteries and DC-to-AC converter(s). The batteries are used for short-term energy storage and the converters provide a controllable interface with grids or electrical loads. At Alfen, we design and manufacture more sustainable energy storage solutions in which power electronic DC-to-AC converters play an important role in managing power and energy flows to grids and in stand-alone power supplies. High-quality mature conversion products are integrated together with batteries to form a Battery Energy Storage System."
Measuring performance during development
René: “During the development we have to address the power losses and the power capabilities of both the DC-to-AC conversion system as well as the performance of the batteries. For these measurements we make use of a set of Delta SM 15k bi-directional AC-DC power supplies. Especially the bi-directional power flow capability is appreciated by our team. In addition, the supported DC voltage range up to 1.5 kV allows the emulation of the latest generation of batteries. Besides the power supplies we make use of a Hioki PW8001 power analyzer for full voltage range power losses and converter performance measurements. A unique Hioki PW8001 feature is the possibility to measure DC voltage and power up to 1.5 kV.”
Test set-up for battey testing
Batteries make up a large part of the system cost, so good performance and characterization of the batteries are important. René: "Before a system is approved, it undergoes extensive testing. We carry out controlled energy cycle tests with the Delta SM 15k power supplies (up to 300 kW). At the same time, we measure relevant electrical quantities with the Hioki PW8001 power analyser. A Hioki 4560 battery tester is used for frequency domain-based battery cell characterisation."
Very good cooperation with CN Rood
CN Rood supplies both Delta Elektronika and Hioki equipment.
René: "We are very happy with the collaboration with CN Rood. The equipment is of high quality and we can rely on CN Rood's advice. The cooperation with CN Rood has turned out to be very good and the fast and adequate response in solving (minor) technical problems has been particularly appreciated. A reliable partner!"