Engineering topics

Kandula, Prasad [ORNL] (ORCID:0000000174017284)

Publications and source records attributed to Kandula, Prasad [ORNL] (ORCID:0000000174017284).

4 records

DOE OSTI2025

10 kV Class 14 MHz Isolated Power Supply

This paper presents a single-switch based isolated power supply, utilizing a PCB based core-less transformer to achieve high inter-winding isolation and low common-mode capacitance. Detailed design procedure, considering the transformer to achieve full range ZVS, minimize voltage stress and minimize RMS currents is presented. The proposed methodology is experimentally validated at 14 MHz, with a load variation of 10:1 in output power and a maximum output power of 4 W. The proposed power supply is useful in applications such as MV gate drives and sensors.

Tessaro Andrade, Elvey [ORNL] (ORCID:0009000225919↗

DOE OSTI2025

A study on dc fault handling of dc-dc converter based on series and parallel connected DABs in MVdc applications

With the increase of direct current (dc) based power generating stations and loads, multi-terminal medium voltage dc (MT-MVdc) systems are gaining popularity. The dc sources and loads are interfaced with the MT-MVdc systems using series and parallel connected dual-active-bridge (SP-DAB). In this paper, the dc fault ride through procedure of SP-DAB meant for MT-MVdc application is analyzed. The need for dc breaker (DCB) under the requirements of MT-MVdc is established through EMT simulation studies. It is shown that an additional dc filter capacitor is essential at the output terminals of the SP-DAB to ride through the dc faults.

Jaldanki, Sreenivasa [ORNL] (ORCID:000000028122322↗

DOE OSTI2025

SCR-based Medium Voltage DC Solid-State Circuit Breaker

This paper describes a medium voltage solid-state circuit breaker (SSCB) based on SCR technology, featuring short fault-interruption time and a minimal turn-off auxiliary circuit. The SSCB design incorporates a specialized SCR and a commutation circuit designed with an objective to reduce the required SCR hold-off/turn-off time, tq, which primarily determines the fault interruption duration. To validate the design, simulation analysis is presented, and a 1.5 kV 300 A SSCB prototype has been built and tested. The results confirm the effectiveness of the proposed design philosophy demonstrating the SSCB's ability to interrupt a 200 A load current in less than 50 μs. The proposed SCR-based SSCB has been developed for DC applications but is equally applicable to AC applications.

Kandula, Prasad [ORNL] (ORCID:0000000174017284)↗

DOE OSTI2025

A Simulation Framework to Support the Deployment of Vanadium Redox Flow Batteries

This work presents a simulation framework to support Vanadium Redox Flow Batteries deployment. First, an electrical equivalent model of a commercial three-stack, 20 kW VRFB is implemented to capture the battery dynamics. Next, a topology of a power electronics-based solution to integrate a VRFB is introduced, and the effectiveness of the control system is evaluated through battery charging and discharging operation under varying conditions. The results provide insights into power and voltage levels, demonstrating that the series-connected architecture can alleviate the voltage boost on the interface power electronics converter. Additionally, efficiency and temperature-critical factors for VRFB system deployment-are also analyzed.

Rezende Da Costa Reis Kimpara, Renata [ORNL] (ORCI↗