A technology company developing the SMART Power Flow Controller - a functional requirements-based, cost-effective solution.
SMART Power Flow Controller is a breakthrough in bulk power system technology, hosting a range of benefits over traditional power flow solutions. SMART Power Flow Controller, a patented technology, acts as an Impedance Regulating Transformer and offers a plethora of power flow control features independent active and reactive power flows, voltage, phase angle, Impedance (XL or XC and R or –R, all independently variable) in one, multi-use unit to provide a reliable, cost‐effective, and portable solution to meet today's needs to modernize the grid.
We strive to serve society by delivering advanced power‑flow control technology. Through publications, tutorials, seminars, and webinars, we educate customers, enabling them to define functional requirements and obtain cost‑effective solutions.
The SMART Power Flow Controller (SPFC) redefines how electricity moves through the grid - offering precise, independent control over active and reactive power. By intelligently managing energy flow, it maximizes efficiency, enhances reliability, and minimizes losses across the transmission network.
Unlike traditional solutions built around a single technology, the SPFC unites the best features of all power-flow concepts developed until now into one, functional-requirements-based system that's simple, scalable, and cost-effective.
The SPFC acts as an impedance-regulating transformer, dynamically adjusting both resistance and reactance in a transmission line. This allows it to control power flows independently, maximizing useful active power and minimizing unwanted reactive power.
While power-electronics-based systems can react in milliseconds, most utility applications only require response times measured in seconds or longer. The SPFC's design meets those real-world functional requirements delivering high performance at a fraction of the cost of power electronics solutions.
How the SPFC compares with the other ways to control power flow on a transmission line.
| Capability | SMART Power Flow Controller | UPFC (Westinghouse) | Phase angle regulator |
|---|---|---|---|
| Independent active power control | Yes: Independent | Yes: Independent | Partly: Tied to reactive power |
| Independent reactive power control | Yes: Independent | Yes: Independent | No: Not controllable |
| Voltage regulation | Yes: Yes | Yes: Yes | No: Phase angle only |
| Impedance regulation (XL or XC, R or -R) | Yes: All independently variable | Yes: Through converter control | No: Fixed |
| Built from proven transformer and tap-changer parts | Yes: Yes | No: Voltage-sourced converters | Yes: Yes |
| Response time | Partly: Seconds, enough for most utility needs | Yes: Milliseconds | Partly: Seconds |
| Cost | Yes: A fraction of power electronics | No: Highest of the three | Yes: Lower |
| Portable and redeployable | Yes: Yes | Partly: Typically fixed | Partly: Typically fixed |
| Component availability over the years | Yes: Long-lived components | Partly: Electronics age faster | Yes: Long-lived components |
Qualitative comparison. See the IEEE papers on the Sen Transformer vs the UPFC and the Sen Transformer vs the phase angle regulator.
A more intelligent, reliable, and sustainable power grid - built around functional principles rather than rigid technologies. The SPFC enables utilities to do more with existing infrastructure, ensuring a smarter, cleaner, and future-ready energy system.
Books, papers, and articles on power flow control by K. K. Sen and M. L. Sen.
By K. K. Sen and M. L. Sen, published by Wiley. ISBN 9780470478752
A comprehensive resource introducing Flexible AC Transmission System (FACTS) controllers, their modeling techniques, and real-world applications. Suitable for students, engineers, and professionals in the power sector.
View on Wiley
By K. K. Sen and M. L. Sen, published by Wiley. ISBN 9781119824381
This book presents proven methods for improving grid reliability and efficiency using SMART Power Flow Controllers. It's ideal for grid planners, operators, engineers, and students in modern power systems.
View on WileyDesigned with Ampcontrol, built at 33 kV, and tested to show that active and reactive power flows can be regulated independently in both directions.
Sen Transformer
Impedance regulating transformer
Ampcontrol is excited to announce that in collaboration with Sen Engineering Solutions, Inc., we have designed, manufactured and extensively tested the world's first commercial-grade Sen Transformer, a patented technology, that acts as an Impedance Regulating Transformer. Sometimes, there comes a technical advancement that is simple, elegant and effective.
Sen Transformer marks the first breakthrough in bulk power system design in more than a century, hosting a range of benefits over traditional power flow solutions. Sen Transformer, which offers a plethora of power flow control features, such as independent active and reactive power flows, voltage, phase angle, impedance (XL or XC and R or –R, all independently variable), all in one unit, uses time‐tested components, such as transformer and load tap changers that are proven to be reliable, cost‐effective, and portable to meet today's needs to modernize the grid.
A commercial-grade Sen Transformer was designed to operate at 33 kV with a throughput rating of ±6.5 MVA. The unit was manufactured and tested to demonstrate the proof of concept. The test results show that the bidirectional active and reactive power flows can be regulated independently, proving that the Sen Transformer is a practical solution to meet utilities' needs in terms of reliability, cost-effectiveness, component non-obsolescence, efficiency, portability and interoperability.
The Sen Transformer is being further tested in a 33 kV radial line at the EPRI lab in the USA.
The engineers behind the Sen Transformer and the SMART Power Flow Controller.
PhD-EE, PE, MBA, IEEE Fellow
President & Chief Technology Officer
Directs all aspects of the company, including R&D/Engineering, Sales and Marketing, Manufacturing, Quality Assurance, and Finance.
MEE, IEEE Member
Chief Operating Officer
Responsible for performing the everyday operations of the company, ensuring efficiency and project execution.
Questions about the SMART Power Flow Controller, a project, or a talk? Send a message and we’ll reply by email.
Kalyan K. Sen
senkk@sentransformer.comMey Ling Sen
senml@sentransformer.com