Description:FIELD OF THE INVENTION
This invention relates to Solid-State Transformer with Integrated Energy Management System for Optimized PV-Battery Microgrid Operation
BACKGROUND OF THE INVENTION
The rapid growth of PV-battery-based microgrids has introduced challenges in power management, grid stability, and operational reliability. Conventional microgrid systems rely on low-frequency transformers and static power distribution strategies, resulting in lower efficiency, voltage fluctuations, and increased power losses. Moreover, existing microgrid solutions often lack adaptive fault-tolerant control mechanisms and dynamic energy distribution strategies, making them vulnerable to grid disturbances.
Solid-state transformers (SSTs) offer compact size, high-frequency switching, and improved power quality, making them an ideal solution for modern microgrids. However, current SST-based systems lack integrated energy management and fault-tolerant mechanisms, limiting their reliability and scalability. The present invention addresses these limitations by introducing an SST-based microgrid with integrated EMS, bidirectional power flow, and fault-tolerant control to enhance energy efficiency, reliability, and grid interaction.
Current PV-battery microgrids face several challenges:
• Limited Efficiency: Traditional microgrids use bulky transformers with lower conversion efficiency and higher power losses.
• Grid Instability: Existing microgrid systems lack advanced control strategies, resulting in voltage fluctuations, load imbalances, and harmonics.
• Fault Sensitivity: Current SST designs lack fault-tolerant mechanisms, making them prone to downtime during module failures.
• Static Energy Management: Conventional systems lack adaptive energy management, making them inefficient in balancing power from PV, battery, and the grid.
Aspect Previous Problem / Challenge Proposed Solution
Efficiency High-frequency operation leads to thermal losses and electromagnetic interference (EMI), reducing overall efficiency (US9490720B1) Use wide-bandgap semiconductors (SiC/GaN) to minimize switching losses; improve thermal design and EMI filtering
Fault Tolerance Limited autonomous fault response; lacks integrated self-healing or predictive diagnostic mechanisms (US11515795B2) Integrate AI-based fault prediction; use modular fault-isolation circuits with real-time system health monitoring
Energy Management Focus is on auxiliary and backup supply rather than active energy optimization between PV, battery, and load (EP4407856A1) Implement adaptive EMS algorithms using real-time data and load forecasting; include flexible dispatch strategies for PV-battery coordination
Power Flow Complex bidirectional converter control and synchronization challenges with varying grid and battery states (US11088655B2) Introduce intelligent power flow management using decentralized controllers and synchronized communication protocols
Grid Stability High-frequency AC-DC transitions can induce harmonics and cause voltage instability at the point of common coupling (PCC) (US9490720B1) Apply active damping techniques and harmonic mitigation filters; implement soft-start and voltage ride-through mechanisms
Size and Weight System rigidity and traditional layout lead to bulkier components not optimized for compact microgrid installations (US11515795B2) Redesign using solid-state transformers with high-frequency isolation and compact magnetic materials; modularize for scalable deployment

SUMMARY OF THE INVENTION
This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention.
This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.
To further clarify advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.
The primary objective of this invention is to develop a Solid-State Transformer (SST)-based microgrid system with an integrated energy management system (EMS) to enhance PV-battery microgrid operations. The invention aims to achieve high efficiency, fault tolerance, and grid stability through dynamic energy distribution and advanced fault recovery mechanisms. It supports bidirectional power flow, enabling seamless grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations. The system incorporates soft-switching techniques (ZVS/ZCS) to reduce losses and improve power quality. Additionally, the redundant SST modules and self-healing algorithms ensure continuous operation, making the system reliable and scalable for large-scale microgrid deployments.
The proposed invention introduces a Solid-State Transformer (SST) with an Integrated Energy Management System (EMS) designed for optimized PV-battery microgrid operations. This system significantly enhances efficiency, reliability, and grid stability through the integration of multi-level SST architecture, bidirectional power flow, and fault-tolerant control mechanisms. The SST utilizes high-frequency switching and soft-switching techniques (ZVS/ZCS) to minimize power losses, reduce harmonics, and improve power quality. The adaptive EMS dynamically manages power distribution between PV panels, battery storage, and the grid, ensuring optimal energy utilization based on real-time demand. Additionally, the system incorporates a fault-tolerant control module with self-healing algorithms, enabling automatic fault detection, isolation, and recovery to ensure continuous operation. The bidirectional power flow capability supports both Grid-to-Microgrid (G2M) and Microgrid-to-Grid (M2G) operations, enhancing grid stability by enabling the microgrid to inject power into the grid during low demand. This invention offers scalable, reliable, and efficient microgrid infrastructure, making it ideal for large-scale PV-battery microgrid applications with enhanced energy management and fault resilience.
BRIEF DESCRIPTION OF THE DRAWINGS
The illustrated embodiments of the subject matter will be understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and methods that are consistent with the subject matter as claimed herein, wherein:
FIGURE 1: SYSTEM ARCHITECTURE
The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.
DETAILED DESCRIPTION OF THE INVENTION
The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
In addition, the descriptions of "first", "second", “third”, and the like in the present invention are used for the purpose of description only, and are not to be construed as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" and "second" may include at least one of the features, either explicitly or implicitly.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
The present invention relates to a Solid-State Transformer (SST)-based microgrid system with an integrated energy management system (EMS) designed to enhance PV-battery microgrid operations. Unlike conventional systems, the proposed invention features a multi-level SST architecture that converts medium-voltage AC to DC and low-voltage AC, enabling bidirectional power flow for seamless grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations. The system incorporates dynamic energy distribution through an adaptive EMS, optimizing power flow from PV panels, battery storage, and the grid. To ensure fault tolerance and reliability, the design integrates redundant SST modules with self-healing capabilities, minimizing downtime during failures. Additionally, soft-switching techniques (ZVS/ZCS) reduce switching losses, improving efficiency and power quality. This scalable and compact system enhances grid stability, reduces harmonic distortion, and supports large-scale microgrid deployments with improved reliability and energy efficiency.
The figure illustrates the SST with Integrated Energy Management System (EMS) for PV-battery microgrid operation. It showcases the system architecture comprising key components such as the PV panel array, battery storage unit, and the modular SST responsible for bidirectional power flow. The energy management system dynamically regulates power distribution between the PV source, battery, and the grid, optimizing energy utilization.
The operational workflow diagram depicts the entire process flow, starting from power generation and grid input to SST-based power conversion, followed by EMS-driven energy distribution. It highlights the fault-tolerant control mechanism with redundant SST modules, ensuring continuous operation during component failures. The bidirectional power flow enables both grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations, enhancing grid stability and reliability.

The proposed system consists of the following key components:
a) Modular Solid-State Transformer (SST):
• Converts medium-voltage AC to DC and then to low-voltage AC for microgrid operations.
• Utilizes a distributed power stage topology to enhance scalability and reliability.
• Incorporates high-frequency switching to reduce size, weight, and power losses.
b) Integrated Energy Management System (EMS):
• Balances power distribution between PV, battery, and the grid.
• Includes real-time load forecasting algorithms and dynamic energy pricing optimization.
• Dynamically allocates power based on grid conditions and generation demand.
c) Fault-Tolerant Control Mechanism:
• Uses distributed redundancy with self-healing SST modules.
• Integrates predictive fault detection algorithms for early diagnosis.
• Ensures seamless switchover to backup modules during failures.
d) Bidirectional Power Flow Control:
• Supports both grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations.
• Enhances grid stability by dynamically regulating power flow.
e) Soft-Switching and Power Quality Enhancements:
• Implements ZVS and ZCS techniques to reduce switching losses.
• Improves power quality by minimizing harmonic distortion.
2. Operational Workflow:
The flowchart visually illustrates the operational workflow of the Solid-State Transformer (SST) with Integrated Energy Management System for PV-Battery Microgrid Operation.
a) Input Stage:
o The system begins by receiving power inputs from three primary sources: the PV array, battery storage, and the grid.
o Each source undergoes individual power regulation through DC-DC or AC-DC conversion.
b) Energy Management System (EMS) Control:
o The EMS dynamically manages and optimizes power flow by analyzing the state of charge (SoC) of the battery, PV generation capacity, and grid stability conditions.
o It prioritizes renewable energy utilization to reduce grid dependence.
c) Power Conversion via SST:
o The SST handles the multi-level power conversion, transforming medium-voltage AC into DC and then back to low-voltage AC.
o It applies soft-switching techniques (ZVS/ZCS) to minimize switching losses and improve efficiency.

a) Fault-Tolerant Control:
o During fault conditions, the predictive fault detection module identifies anomalies and triggers the self-healing mechanism.
o The system seamlessly switches to redundant SST modules, ensuring uninterrupted operation.
b) Bidirectional Power Flow:
o The system supports both grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations.
o During low grid demand, the microgrid exports surplus energy back to the grid (M2G mode).
o During peak grid demand, the system imports power to charge the battery or supply the microgrid (G2M mode).
c) Real-Time Monitoring and Feedback:
o Continuous monitoring of voltage, current, and power quality ensures real-time adjustments for optimal performance.
o The EMS maintains grid stability by mitigating voltage fluctuations and harmonic distortion.

E. NOVELTY:
The proposed Solid-State Transformer with Integrated Energy Management System for Optimized PV-Battery Microgrid Operation offers the following novel features that distinguish it from existing solutions:
1. Modular SST with Distributed Redundancy:
• Unlike conventional SST designs, this system uses a distributed modular SST architecture with self-healing capabilities.
• It ensures continuous operation by automatically switching to redundant SST modules during failures, enhancing reliability and minimizing downtime.
2. Integrated Adaptive EMS with Real-Time Optimization:
• The invention features a real-time adaptive energy management system (EMS) that dynamically balances power flow between PV, battery, and the grid.
• It incorporates load forecasting algorithms and dynamic energy pricing strategies to optimize microgrid performance.
3. Bidirectional Power Flow Control:
• The system supports grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations, enabling dynamic power exchange with the grid.
• This bidirectional flow enhances grid stability by injecting excess power during low demand and drawing energy during peak conditions.
4. Soft-Switching Techniques for Efficiency:
• The SST employs Zero-Voltage Switching (ZVS) and Zero-Current Switching (ZCS) techniques to reduce switching losses.
• This improves overall system efficiency and reduces power losses compared to conventional hard-switching designs.
5. Fault-Tolerant Control with Predictive Fault Detection:
• The system includes an advanced predictive fault detection algorithm that identifies potential failures before they occur.
• This proactive monitoring ensures early diagnosis, preventing major disruptions.
6. Compact and Scalable Design:
• The high-frequency switching architecture significantly reduces the size and weight of the transformer, making the system more compact and scalable for large-scale microgrid deployments.
• Its modular structure allows for easy expansion and improved adaptability to varying load conditions.
7. Grid Stability and Power Quality Improvements:
• The system actively regulates power flow, mitigating harmonic distortion, voltage fluctuations, and load imbalances.
• It enhances overall power quality and grid stability, making it suitable for large-scale renewable energy integration.
8. Dynamic Renewable Prioritization:
• The EMS prioritizes renewable energy utilization, reducing dependence on the grid.
• This feature optimizes energy efficiency and promotes sustainable microgrid operations.

 
, C , Claims:1. A Solid-State Transformer (SST)-based microgrid system, comprising: PV panel, energy management system, soft switching techniques and bidirectional power flow.
2. The system as claimed as claim 1, wherein the system aims to achieve high efficiency, fault tolerance, and grid stability through dynamic energy distribution and advanced fault recovery mechanisms.
3. The system as claimed as claim 1, wherein the system features a multi-level SST architecture that converts medium-voltage AC to DC and low-voltage AC, enabling bidirectional power flow for seamless grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations.
4. The system as claimed as claim 1, wherein the system enhances grid stability, reduces harmonic distortion, and supports large-scale microgrid deployments with improved reliability and energy efficiency.
5. The system as claimed as claim 1, wherein the system The bidirectional power flow enables both grid-to-microgrid (G2M) and microgrid-to-grid (M2G) operations, enhancing grid stability and reliability.
6. The system as claimed as claim 1, wherein the system including an advanced predictive fault detection algorithm that identifies potential failures before they occur.