Development of a Utility Grade Controller for Remote Microgrids with High Penetration Renewable Generation

Lead Proponent:  Hatch Ltd.
Location:  Mississauga, ON
ecoEII Contribution:  $ 2,224,000
Project Total:  $ 3,483,000

Project background

Canada has over 300 remote communities, as well as a significant number of off-grid metal and mining companies.  The variable cost of diesel fuel, the challenges and cost of shipping fuel, the decreasing cost of renewable energy, and the desire to avoid the environmental and social costs of diesel power generation are all driving these communities and companies towards renewable generation, in order to offset their energy costs.  However the intermittent nature and power fluctuations of renewable power sources such as wind and solar power, combined with low inertia of small isolated power systems give rise to power quality and stability issues that require advanced dynamic load-generation balance control.  In addition, with multiple generation assets on a system, economic dispatch of assets becomes complicated.  In remote and isolated micro-grids, robust dynamic control and optimal economic dispatch utilizing load and renewable power forecasts require the deployment of a resilient real-time control system.  Recognizing the need, Hatch proposed the project “Development of a Utility Grade Controller for Remote Microgrids” for ecoEII funding.  The Project was awarded $2.224M to develop a commercially viable controller that facilitates the integration of renewable power and energy storage into remote microgrids while maximizing performance and maintaining system stability.

Results

Hatch, utilizing research performed in University of Waterloo, designed and developed the Hatch Microgrid (HμGrid) - a utility grade controller that handles the energy management and power-flow control of microgrids with renewable generation.   HμGrid incorporates modules for: power system measurement, dynamic power shaping, supervisory control, optimal economic dispatch, as well as, energy storage, generator limit, smart load and output management.  The controller software architecture is comprised of a fast measurement layer which performs phasor calculations using a ½ cycle window, and a real-time layer which implements control algorithms and performs prediction and optimization.  Testing of the controller, using a method called Hardware in the Loop (HIL), was done in collaboration with the University of Toronto.  HIL testing involves real time simulation of a power system which provides electrical measurements to and accepts set points from the controller.

As part of a separate project to assess the impact of flywheels on stabilizing isolated renewable microgrids, a version of HμGrid was installed at the Alaska Center for Energy and Power.  Its performance and ability to control a high speed composite flywheel was assessed.  The controller was able to improve power quality and operate the microgrid in “diesel-off” mode.  Moreover, in another isolated renewable microgrid project at Glencore’s Raglan mine in northern Quebec, HμGrid was installed to monitor the demand for wind power and variations in supply, and economically dispatch the charge and discharge of various types of energy storage units, to enable higher wind power penetration and displace diesel generation.

A desktop simulation was performed in order to assess the ability of the controller to optimize the economic performance of two interconnected (via 25kV tie-line) remote microgrids, without the addition of renewable power generation.  Through simulation, it was determined that the two communities could realize fuel savings of up to 5.3% while reducing total generator runtime by 15%, as well as reduce the number of generator starts by 70%.

Finally, a year-long measurement campaign was conducted in collaboration with the Kasabonika Lake First Nation (KLFN) community.  Several types of instruments were installed in the community to measure different aspects of power quality in the power system, including the diesel plant, the solar farm, the wind farm and various loads.  A report was prepared characterising the power quality of the KLFN system.

Benefits to Canada

The utility-grade controller for remote microgrids is an enabling technology; it maximizes the use of renewable power sources, minimizes the consumption of diesel fuel, and ensures the most efficient use of an energy storage system and power generation assets.  Affected communities and industries benefit from reduced emissions, improved power generation efficiency, and reduced energy costs.

Next Steps

Hatch intends continue to improve the HμGrid design, as well as efforts to commercialize and export the controller for remote microgrids.  Pilot projects at selected communities in Canada will be pursued.

Find out more

• Public Report:  Development of a Utility-Grade Controller for Remote Microgrids