PNDC optimizes their Triphase power conversion system creating a game changer across their testing capabilities
The Power Networks Demonstration Centre (PNDC) is a unique facility playing a leading role in the transition to a smart grid and the acceleration of low carbon technologies. As a research, demonstration and deployment centre for emerging technologies, it offers a realistic and controllable testing environment helping to de-risk potential solutions before connecting to the grid and helping to develop the next generation of electrical power systems technologies. A broad-based test facility, PNDC wanted to expand their existing Power Hardware in the Loop (PHIL) test capability and reached out Triphase for guidance.
In the nine months since the installation, the initial project has organically expanded to encompass other test projects across a diverse range of applications. This would not have been possible without the flexibility of the Triphase platform and the ease of experiment setup that it provides.
It is a testament to the flexibility of the Triphase platform that we’ve been able to expand so far beyond our original test plans and without needing any hardware changes.
PNDC had a kick-off project planned, where they wanted to test a flywheel energy storage system for retrofitting into existing naval power systems. The test required generating a bidirectional DC voltage to supply the flywheel inverter as the device under test (DUT). The voltage supplied to the DUT had to be adjusted dynamically based on a closed loop RTDS simulation of the complete electrical naval grid.
Given PNDC is constantly looking to expand the capability and size of the centre, long term usage and the potential to expand the capability of the Triphase system in the future was one of the key criteria in the design specification of the system. Ideally, they wanted to produce a breadth of different voltage and current waveforms and have the versatility to configure the Triphase as AC/DC voltage/current source for active/passive loads and sources. Since commissioning, the Triphase system has been vigorously tested for projects and has demonstrated its flexibility for a variety of different project applications.
Triphase developed and built a multifunctional and flexible power conversion system suitable for a wide range of operation modes:
- 500 kVA bidirectional AC grid emulator
- 500 kW, -1300 to 1300V bidirectional DC supply (voltage and current source)
- 500 kVA soft open point
- 1 MVA active front end / filter
- 500 kW, 0 to 1300V bidirectional battery interface
The power conversion system is realized using Triphase’s modular power system (PMx) product line. The proposed system consists of 12 inverters, but can be expanded at any time to increase power or current ratings or provide additional functionality. As a result of the PMx approach, switching between the operation modes listed above does not require any hardware changes, PNDC only has to reconfigure the software and connections. All operation modes are controllable directly in Matlab/Simulink, via the provided user interface or through RTDS via a direct real-time optical fibre link. As the software is open, new applications and test scenarios can be added on the fly, either supplied by Triphase or programmed by PNDC personnel.
The PNDC centre is continuing to grow as is the range and breadth of research areas being undertaken at the facility with the Triphase system. The projects range from replacing ship to shore demonstrators, to technology for interfacing energy storage to ship power systems, and onto evaluating the impact of futuristic load requirements. The research areas are not only in the naval domain, their Triphase projects have expanded to cover land utility based systems including evaluating power quality in hybrid, solar and diesel power systems. PNDC uses the system on a daily basis to support projects, transitioning from a few applications to more than seven different types including:
- Naval Power System Power Hardware in the Loop studies
- Solar hybrid power system testing
- Phase balancing technologies
- Inverter penetration impact studies for the system operator
- Power quality, phase balancing and energy saving technology testing
- Studies for emulating a fixed impedance load
- Studies for creating loads with large harmonic content
- Support of the ERIGrid program: Users from research, academia and industry are invited to apply for free access to top European smart grids research laboratories of ERIGrid partners. (including the PNDC)
|PNDC uses the full spectrum of the Triphase system. The original scope of delivery was 3-phase 3-wire AC voltage operation. However, it evolved with additional software apps to one which allows 3-phase 4-wire operation (= 3-phase + actively controlled neutral), AC Current Source operation, and single and multi-channel DC voltage and current source operation.|
|The system had approximately 30-40% usage over the 9-month time frame since PNDC acquired the equipment. Considering not all tests use the Triphase system, that is considered a very heavily utilised component. Over that time, there had been at least one month where it was running every day for 8+ hours.|
Set-up time for a new experiment
|PNDC was supplied with training from Triphase and had an internal team of five researchers that were quick to ramp up utilisation of the system. However, they also had access to continuing support from Triphase subject matter experts. Given their high admission of new research, they estimate their new experiment set-up time to range from 1 hour to 1 week depending on the novelty and complexity of the study.|
|The PNDC system was developed to ensure ease of expanding the power from 1 MW to 2 MW. This can be accomplished simply by adding additional power module units and making minor adjustments to the software.|