Areas of Research Expertise: Renewable and Distributed Power Systems
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Background: Engines & Energy Conversion Laboratory
The Engines & Energy Conversion Laboratory (EECL) is a unique research/education program housed in the Department of Mechanical Engineering. The laboratory was established in the Old Fort Collins Power Plant in June 1992. In the years since then the laboratory has grown to become one of the largest and most influential engines research programs in the United States. The EECL is widely recognized as an international leader in the fields of large gas engines for power generation and compression, small 2-stroke cycle engines for use in developing countries, alternative fuels for automobiles, computational fluid dynamic (CFD) modeling of engines, and optical combustion diagnostics. The Department has invested in the laboratory through the recent hires of two new faculty members who have established new EECL programs in diesel engines, laser diagnostics, and plasma applications in engines.


The InteGrid laboratory ranks among the world's most advanced centers for test and development related to renewable energy, distributed generation, and power system management. Contained within the laboratory are multiple generators (natural gas gensets, microturbines), load banks, frequency and voltage stabilizers, and switchgear - all connected to the grid with the ability to import and export power.

An InteGrid Overview

The InteGrid Test and Development Laboratory www.integridlab.com provides a test platform for experimentally verifying SmartGrid controls and control strategies. The laboratory contains hardware which emulates part of the distribution grid at a scale of roughly 40:1 - economically sized while capturing the key dynamics of the distribution environment. InteGrid is growing rapidly, with major new equipment slated for installation in early 2010.

Dynamic Wind Turbine Simulation

The Wind Turbine Simulator emulates wind resources through physical and dynamic simulation. A single machine simulates 4-8 induction-generator based wind turbines, up to a combined total of 100kW of scaled wind power. Each turbine can be assigned its own performance profile, allowing the impact of different types of turbines and varying profiles to be simulated. The supervisory control system sees eight individual turbines with different production characteristics and can send control signals to each individual turbine.

Transmission Connection and Substation Emulationn

The InteGrid Lab has an interconnect agreement, including parallel and export operation, with the local utility, Fort Collins Utility, through a 480V-13.2KV transformer. The 750 KVA service will be upgraded to 1500 KVA during early 2010.

Industrial switchgear emulates the disconnects and circuit breakers normally found in an electrical substation. All generator breakers are remotely controlled by through a hierarchical control system. A flexible, research-type interconnect agreement allows InteGrid to test strategies which include import/export control, intentional islanding, and resynchronization for hybrid power systems.

Conventional Natural Gas Reciprocating Generators

Two 100KW natural gas generator sets emulate combined heat-and-power plants, or similar distributed generation. The generators are equipped similarly to distributed generation systems, and can act individually or as dispatchable generation resources. The generators are capable multiple operating modes, such as baseload, droop, isochronous master, and isochronous load sharing. Additional generators, including a 500 KW Caterpillar diesel and a 300 KW Waukesha natural gas engine will be added during the 2010.

Utility Style SCADA Control Room and Communications

InteGrid implements a utility-style SCADA system, based upon a Control MicrosystemsTM platform. The SCADA system manages all major resources, and includes a management HMI as well as a development platform for controls development. The lab remains flexible: Additional SCADA systems can be supported as required.

Since the lab is set up to emulate a distribution network, individual assets communicate only through high level communications media to emulate distance communications in real distribution systems. Hardwired links common in small installations for multi-asset coordination are not utilized. The SCADA system communicates with individual assets using protocols appropriate to the asset, including MODBUS, MODBUS/TCP, TCP/IP and emerging protocols, such as IEC61850.

The laboratory also implements extensive data acquisition using system from National InstrumentTM and YokogawaTM.

Utility Load Simulator

A 400 KW/300KVAR LoadTecTM load bank emulates system loads. Variable system loads are managed through a Utility Load Simulator that can emulate 1-8 feeder lines. The simulator can utilize manual control or "read back" profiles collected in the field.


Two micro turbines add to the lab's diverse resource mix. The turbines, from BowmanTM and Ingersoll RandTM, operate at approximately 80 KW each. The Bowman operates as a combined heat and power plant for the Engines and Energy Conversion Lab. Both units represent significantly different operational characteristics than conventional generation, adding diversity to the lab's resources.

Secondary Load Controller and Synchronous Condenser

The Secondary Load Controller (SLC) provides fast, high-resolution resistive load up to 100 KW. A 125 KVAR KatoTM synchronous condenser (SC) provides high-speed reactive power control to provide voltage support. On a small system, such an islanded micro-grid, these systems act as "shock absorbers." The SLC reacts quickly to balance generation and load. Similarly, the SC's excitation control provides rapid adjustment reactive power. In island operation, the SLC can act as "frequency master," providing transient support to slower generators, while the SC can act as "voltage master," maintaining the system voltage.

InteGrid Future

InteGrid is growing... fast. In addition to the resources above, significant new equipment will be implemented during early 2010 with committed funding, including:

A 50 KW Photovoltaic System Simulator

The PV simulator will emulate the operation of utility-connected photovoltaic systems, as well as providing a testbed for inverters and other power electronics. The system will be driven by a 50KW high-speed, controllable DC power supply, capable of emulating most I-V curve dynamics from 2-50 KW. The system will split into two 25KW supplies, to emulate multiple systems, potentially connected on isolated bus bars.

Interconnect and Switch Gear Expansion

A major switchgear extension will triple the number of breakers and busses available for emulating distribution systems. Busses can be linked directly, or decoupled through paired transformers to emulate distribution impedances. The utility interconnect will be upgraded to two independent transformers, allowing independent power feed/export operation.

Plug-in Hybrid Electric Vehicle Connections

Connections for two or more PHEVs will feed into the lab, supporting work in controlled charging, vehicle-to-grid export and similar strategies.

Additional Conventional Generation Systems

Two additional generators - a 500 KW Caterpillar 3412 genset and a Waukesha 300 KW genset - will be implemented in early 2010, in parallel with the lab. Either unit could be routed into the lab to support testing.

Waste Heat Generation System

An organic Rankine cycle (ORC) research system will utilize waste heat from other laboratory engines to generate electricity. The ORC system will utilize an innovative turbine, induction generator and regenerative solid-state drive. The system will serve as a test bed for ORC cycle improvements, cost reductions and interconnect studies.

Fuel Cell Generation System

A fuel cell connection point will be implemented, allowing the testing of fuel cells and similar storage systems.

What's next? The sky's the limit!