Flexible Power Electronics Configuration for Coupling RES and Storage

Introduction

Nowadays, power electronics are applied in many applications, playing a critical role on the transformation of the current electric grid into the next-generation grid.

The use of rapid prototyping tools provides the designer with a powerful platform to test and develop new ideas and concepts. These rapid prototyping approaches greatly reduce the time and effort required for the overall design process. Traditionally modeling/simulation and implementation have been two distinct tasks. Rapid prototyping tools aim to bridge the gap between simulation and implementation and make the power electronic circuit design as simple as possible.

At Smart RUE lab the simulation of distribution network under future scenarios is thoroughly analyzed. An integral part of this process are the Triphase’s Distributed Power Modules that realize a scalable, flexible and open platform for rapid prototyping of power conversion and power system applications.

The setup

The figure below shows an outline of the SmartRue’s power electronic test bed architecture. The setup consists of a 15 kVA bidirectional active frontend (DC/AC), and a 15 kW bidirectional DC/DC converter consisting of 3 channels.

The Power Modules are fully reconfigurable and open. Researchers have access to all data and can change all the software from the highest level (e.g. coordination and control of power flows between the storage and the grid) down to the lowest level (e.g. PWM control). Currently the module is operated as a 3ph inverter to interface a battery storage system or as a 1ph-3-leg back to back converter (AC/DC/AC) for power amplification.

Image
All converters are connected to a single DC bus which is accessible to external DC sources (e.g. Dc simulator). The open, reconfigurable and fully reprogrammable structure of the Power Modules can readily be adapted to new research areas.

Highlights: Key specification and capabilities of the setup
  • Active front-end through a bidirectional 3ph AC/DC power converter rated at 15kVA, allowing for active and reactive power flows control and provision of ancillary services (e.g. frequency and voltage support, power quality improvement etc.).
  • Controllable DC bus carrying a number of DC/DC converters able to interface and fully control voltages and currents of up to 3 different distributed generators and storage (e.g. Photovoltaics , Batteries, Super Capacitors)
  • DC/DC converters provide a range of voltages  up to 650V at 5kW each. All power converters are built around a re-programmable hardware platform.
  • Software design is open, flexible and based on Matlab/Simulink® software libraries for high-end, real-time control. Users can easily create and test the performance of newly designed control methodologies.
  • Communication interfaces based on open standards (Modbus TCP/IP) allowing interfacing with any 3rd party system (e.g. Smart Home Intelligence Controllers (SHIC), Smart Energy Management Systems (SEMS)).
Performance The Triphase Power Modules are designed to meet AC source requirements for use in compliance testing such as IEC 61000, 3-2, 3-3, 3-11 and 3-12.