Facilities and Equipment
Flexible Integration Laboratory for Distributed Energy Systems (FIELD) at the University of Alabama is equipped to test grid integrated power electronics research. There is >100 kW of three-phase grid connection and three single-phase 50A power outlets to perform power electronics grid integration and analysis tests on various testing power levels. Below is a summary of the important capabilities at FIELD.
1. EV grid integration equipment: FIELD has a Nichicon 4.5 kW vehicle-to-load (V2L) power supply called Power Mover that can be connected to a CHAdeMO compatible EV (shown below). This type of set-up can be used to power loads during emergency conditions. We also have a 25 kW eMotorWerks charger and CHAdeMO DC connector. This test setup can be used for any CHAdeMO compatible EV fast charging tests. Finally, FIELD has two units of 40 A Level 2 eMotorWerks JuiceBox EVSEs.
2. Power grid simulation and testing equipment: A real-time hardware-in-the-loop (HIL) test set-up is available for grid simulation and analysis. Below figures show the critical components of this test system. A digital real-time simulator (OPAL-RT OP5600) is used for real-time modeling and simulation of power grid. It is a multi-core target platform that consists of 12 INTEL processor cores at 3.0~GHz including a SPARTAN-3 FPGA card as the I/O interface with 256 analog and digital I/O lines. There are three racks of this unit to be utilized for testing to implement the large scale power electronics integration testing. Further, FIELD has an Ametek 22.5 kVA single-/three-phase four-quadrant AC/DC power supply a.k.a. grid simulator that can work in conjunction with OP5600. Last, a Yokogawa DL850E is used for signal measurement and recording purposes when doing experiments for extended durations. A connection of those units are shown in the below-right figure.
3. Power electronics simulation and testing equipment: FIELD has all the capabilities of an advanced power electronics laboratory. Power electronics design and operation within the grid integrated systems are the main research themes in FIELD. The below picture shows a custom designed 10 kW three-phase back-to-back voltage source inverter system called DEMT. The back-to-back inverter system is composed of a dual three-phase inverter ready to be interfaced with dSPACE MicroLabBox development system. This system is rated with the maximum switching frequency of 20 kHz and a maximum input/output voltage of 750 VDC. For the three-phase modules, APTGT50A120T1G IGBTs from Microsemi with SP1 package is used. The system can also be readily used with the same-package SiC devices. This custom designed system (DEMT) matches one-to-one with rapid prototype environment provided by dSPACE MicroLabBox also shown below. We also have a Typhoon 402 HIL simulator with an interface for TI C2000 DSPs. This set-up helps us to fast develop power electronic circuitry and develop controllers. Finally, we have different Cree SiC device and gate drive evaluation boards for ready to use testing.
4. Other lab equipment: Other related power electronics testing and measurement equipment are listed as follows.
5. Field testing equipment: We collect real household power consumption data using eGauge core as shown below. This data collection provides us end-node voltage, current, phase angle, active/reactive power consumption of different residential houses. The device allows the storage of the data and syncs to the cloud with one-second granularity and up to two weeks of duration.