Preventing the establishment of invasive species
In the realm of environmental conservation, the battle against invasive species remains a significant challenge. In the context of the Great Lakes region, the invasion of species like Asian carp poses a severe threat to the ecological balance. For this reason, The Fish Barrier Project was started. This project is an initiative under the umbrella of the Great Lakes Restoration Initiative (GLRI) led by the U.S. Army Corps of Engineers (USACE).
Combating invasive species
The urgency of the project is underscored by concerning observations in key areas of concern. The presence of Asian carp spawning in the Marseilles pool, coupled with verified identification of Asian carp eggs and larvae near Henry, III (Peoria Pool), highlights the pressing need for proactive intervention. Despite efforts over the years, the leading edge of the Asian carp invasion has remained largely unchanged since 2006, underscoring the critical importance of robust measures to halt their advance.
Astrol’s contribution to the fish barrier project
The Fish Barrier Project embodies a “zero tolerance policy” towards new invasions. Recognizing the threat posed by invasive species to the delicate balance of ecosystems within the Great Lakes region. Astrol delivered crucial technology in the form of pulsed power switches to fortify the efforts of GLRI in the Fish Barrier Project.
Pulsed power switches
Our innovative technology is deployed at strategic locations along the waterways. The installation of barriers equipped with Astrol’s pulsed power switches represents a cutting-edge approach to invasive species management.
At the heart of these barriers are two different versions of pulsed power switches supplied by Astrol; a smaller switch boasting 2 kV DC and 10 kA, and a larger switch with 3.4 kV DC and 30 kA. These switches form an integral component of the barrier system. Ensuring swift and effective response to potential breaches.
Specification for 2.0kV / 10kA IGBT: SMALL Switch
- Charge Voltage: 2.0kV DC (max)
- Peak Current: 10kA
- Pulse Length: 1ms – 7ms typically
- Maximum power: 250kW (maximum power depends on water)
- Pulse Shape: LR shaped rectangular pulse form
- Current Rise Rate: Depends on inductance and resistance of water
- Pulse Rep. Rate: 100Hz (max)
- Switching Components: IGBT Vces = 3.3kV
- Cooling: Deionized water
- Auxiliary Supply: 120V AC
- Environmental: Indoor in cabinet
- Production Status: Qualified series production
Specification for 3.4kV / 30kA IGBT: BIG Switch
- Charge Voltage: 3.4 kV DC (max)
- Peak Current: 30 kA
- Pulse Length: 1ms – 7ms typically
- Maximum power: 1MW (maximum power depends on water)
- Pulse Shape: LR shaped rectangular pulse form
- Current Rise Rate: Depends on inductance and resistance of water
- Pulse Rep. Rate: 100Hz (max)
- Switching Components: IGBT Vces = 32 x 6.5 kV in parallel connection
- Cooling: Deionized water
- Auxiliary Supply: 120V AC
- Environmental: Indoor in cabinet
- Production Status: Qualified series production
The ‘Chopper’
The 3.4 kV / 30 kA chopper presented by Astrol has been successfully manufactured and tested both in-house and in real-world conditions. Astrol’s collaboration over several years has culminated in the realization of this product. Following rigorous experimentation, the systems have been qualified and are now poised for installation in various rivers and canals. The high reliability and extended lifespan of the chopper were pivotal factors driving its suitability for this application.
Mechanical construction
Operation voltage levels
- Barrier IIA: Operates at 2.3 volts/inch, 30Hz, 2.5 ms pulse width
- Barrier IIB: Operates at 2.3 volts/inch, 30Hz, 2.5 ms pulse width
A diverse set of components
The complexity of the switch system is evident in its intricate design, comprising a range of components meticulously assembled for optimal performance. From control boxes to power supplies, IGBT devices to crowbar diodes, Astrol’s switches are a testament to precision engineering and reliability. Moreover, comprehensive safety features such as MOV protection and water manifold systems ensure the durability and resilience of the barrier infrastructure even under challenging conditions.
Trigger generator
The pulsed power switch (big switch) has 32 IGBT devices in parallel connection. The gate units are all triggered at the same time. The trigger generator has 32 individual optical transmitters and receiver pairs. Each transmitter output has a controlled light output level as well as a defined transmit and receive delay time.
Power supply
The current source power supply produces a pulsating current to energize the inductive couplings of the gate units through a HV cable for isolation reasons.
Gate unit
- Fits on every standard High voltage IGBT (4.5 kV & 6.5 kV)
- Collector voltage sense (dv/dt control, active clamp)
- Glass- or plastic optical fiber
- Current loop power supply for easy powering
- Programmable Vgeon/Vgeoff voltage
- Programmable rise of rate of gate voltage
- Programmable error behavior
Collaboration, innovation and planning
Our collaboration with the Fish Barrier Project underscores our commitment to provide customized technology tailored to the specific needs of our customers. Astrol empowers initiatives like the Fish Barrier Project to contribute to the protection of native ecosystems and preserving the ecological integrity of the Great Lakes region. Furthermore, our involvement in the Fish Barrier Project showcased the potential for innovative solutions. The project demonstrates the power of collaboration, innovation, and strategic planning in addressing complex environmental challenges.
