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@article{186257,
        author = {YALLA RAVI KUMAR and Dr. B. Amarendra Reddy},
        title = {MODELING OF MULTI DC INPUT - AC, 30, 400HZ OUTPUT HYBRID CONVERTER FOR UNDER WATER MARINE PLATFORM CONTROLS},
        journal = {International Journal of Innovative Research in Technology},
        year = {2025},
        volume = {12},
        number = {6},
        pages = {385-407},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=186257},
        abstract = {Marine platforms rely on advanced Control systems to manage and monitor essential operations such as Power Generation & Distribution, Propulsion Control, General Ship system and Central coordination of functions. These systems typically operate at 400Hz to ensure reliable, stable, & fault-tolerant power delivery for subsea equipment incl. sensors, actuators & communication devices. A 3-Tier reliability architecture - comprising Main, Reserve & Emergency mode to ensure power supply availability in all regime’s operation.
This project analyzes the behaviour and common defects of existing Russian-made DC-AC Rotary frequency converter fitted onboard underwater platform, offering both short- and long-term solutions. The cost and availability of spares, largely imported, are significant concerns.
The converter under study (I/P: 175–320V DC, O/P: 3Ph, 230V, 400Hz, 50KW) uses a DC Compound Motor and AC Generator mounted on a common shaft. Its heavy rotary armature makes unit bulky, difficult to handle, and alignment onboard. This system produces significant noise and requires frequent maintenance due to issues such as Excitation circuit repairs and cleaning of commutator, slip-rings, and carbon brushes. Additionally, Compatibility issues with onboard AC-AC rotary frequency converters (50–400Hz, 50KW, two units) complicate repairs at sea using cannibalized parts, affecting operational reliability. 
To mitigate these issues, all three onboard frequency converters (two AC-AC and one DC-AC) have undergone component homogenization through local Indigenization, reducing reliance on imports and improving part compatibility. Integration of modern Static power electronic devices enhances control over non-linear loads, while optimizing the DC-DC conversion stage prior to inversion provides a more stable, regulated DC link voltage, lessening strain on the final conversion process and boosting power quality at the distribution level. Additionally, employing permanent magnet rotor-based motor-generator sets as rotary converters further simplifies mechanical construction and logistics, making installation and maintenance more efficient for marine applications},
        keywords = {},
        month = {November},
        }