Engineering topics

Jaldanki, Sreenivasa

Publications and source records attributed to Jaldanki, Sreenivasa.

4 records

DOE OSTI2026

Generalized Power Flow Model of an Extra High-Power Multi-Terminal HVdc Transmission Grid with Parallel-Connected and Voltage-Stacked Converters

To increase power transfer capacity of high-voltage direct current (HVdc) transmission, a new extra high-power HVdc architecture with multiple standard modular multilevel converters (MMCs) per substation has recently been introduced. This paper proposes a power flow model for a multi-terminal HVdc (MTdc) grid with this innovative substation architecture. The proposed MTdc model can be integrated seamlessly with existing ac-dc power flow algorithms with minimal modifications. The model is applicable to various MTdc grid types and topologies, different numbers of dc buses, dc lines, and MMCs per substation, along with diverse control parameters. In addition, it accurately captures both balanced and unbalanced operations of the MTdc grid. The proposed model is verified using a 5-terminal bipole MTdc grid that spans 4 areas in the Eastern Interconnection system of the USA. The numerical solutions obtained from unified and sequential ac-dc power flow algorithms under different operating conditions closely match the time-domain simulation results in PSCAD, validating the accuracy and versatility of the proposed MTdc power flow model.

Nguyen, Quan H.↗

DOE OSTI2024

A new HVdc Substation Architecture with Higher Power Transfer Capability

The power transferred through high voltage direct current transmission (HVdc) systems is increasing with increased resilience and reliability needs as well as large scale deployment of renewable energy systems. In this paper, a new HVdc substation (SS) architecture with higher power transfer capability is proposed. The HVdc converters or valve groups (VG) are connected in series and parallel fashion such that the total power rating of the SS is increased. The control challenges associated with such SS architecture are identified and appropriate control modifications are proposed. The same is verified through PSCAD based simulations.

Jaldanki, Sreenivasa↗

DOE OSTI2024

Multiterminal High-Voltage dc Systems with Series-Parallel Valve Group-Based High-Voltage dc Substations

To transfer large amount of power over long distances, multiterminal direct current (MTdc) system based on bipole high-voltage direct current (HVdc) technology is a viable option. However, such system results in large dc transmission loss. The same can be reduced by increasing the dc voltage level. This paper introduces a new MTdc system architecture comprising of series (for increasing dc voltage level) and parallel (for increasing dc current capability) connected HVdc converters. The new architecture is compared with the bipole MTdc architecture in terms of equipment needed and dc transmission loss. The control modifications needed for the MTdc system are identified and the performance of the developed control is verified through electromagnetic transient (EMT) simulations.

Jaldanki, Sreenivasa↗

DOE OSTI2024

Study on Conversion from an Existing Alternating Current Medium-Voltage Line to a Direct Current Line: A Case of Load or Source Expansion

Simultaneous increase of power generation through renewable systems and load due owing to the rapid growth in electrified road transportation systems, leads to new challenges in the design, operation, and protection of distribution-level electrical power systems. This paper addresses challenges related to the integration of new sources or loads to a distribution grid through long alternating current lines. The International Council on Large Electric Systems medium-voltage benchmark model developed for North America was used for simulation studies. Use cases were developed to illuminate the issues related to long alternating current lines and the usefulness of medium-voltage direct current lines in a distribution network.

Jaldanki, Sreenivasa↗