To analyze the strengths and weaknesses of existing data silos for the financial and regulatory factors for data unification across generation, transmission, distribution and trading
To identify the financial and regulatory factors affecting the operational analysis of the power sector and constraints impeding the development and implementation of a unified data platform
Abstract
In the last few decades there has been an organic growth of power sector in India. This growth inherently bought with it, problems related to humonguous enhancement of systems, restructuring of the sector, modification of the policies and develop frameworks to handle the scale of future capacities. The integration and interconnections of different stakeholders in the power sector has increased the quantum of software, hardware, tools and data volume manifold.
Data from generation, transmission, distribution and trading was already available in silos and we added to it the complexity of interoperability between stakeholders like organization, application, information systems, social, economic, regulatory and technical infrastructure. It is important that these silos interoperate with each other for attaining operational excellence in a competitive environment.
This paper tries to identify the various factors that need to be analysed to implement a Unified Data Platform (UDP) for the power sector and its interconnections.
Introduction
In India, due to the large geographic spread and the scattered availability of natural resources the load centers are distributed across regions making east and northeast power surplus and northwest and south being power deficient. Monitoring the grid on real-time is vital for optimal operation, to minimize blackouts and grid tripping and to manage the huge and hierarchical network of load despatch centers and facilities across the country.
The structure of the Power Sector
Main segments of the power sector are
The legacy power sector structure in India
The Vertically Integrated State Electricity Boards (SEBs)
Restructured Power Sector – Pre Electricity Act 2003
Restructured Power Sector – Emerging Scenario (Post Electricity Act 2003)
To operate smoothly across this large geography and periodic restructuring, the power grid is controlled at three levels namely National Load Despatch Center (NLDC), Regional Load Despatch Center (RLDC) and State Load Despatch Center (SLDC) levels. Major effort for unification of operation and control was started in early 1990’s and the protocol Unified Load Despatch and Communication (ULDC) was conceived to monitor, operate and control the power grid in a unified and coordinated manner. The ULDC scheme, its objectives, hardware and software architecture, and the benefits of the unified approach are defined in [5].
Despite the ULDC structure, hinderances arise due to the fact that utilities across the sector are using heterogeneous infrastructure, vendor specific hardware with proprietary software, modified Inter Control Center Protocol (ICCP), and lack of common standards which make it difficult for seamless and unified data exchange resulting in inefficient operation of the grid.
These barriers can be removed by designing a Unified Data Platform (UDP) to manage the huge interconnection of data, application, protocols and infrastructure across the intra-regional power network. The UDP needs to be designed to fascilitates semantic interface between the systems available in silos by standardizing data and information exchange. The UDP should define methods and protocols for better interface between applications, robust interconnectivity and to reduce the number of data adapters for speed and reliability.
In the interoperability framework was prepared by GridWise Architecture Council [3, 4], interoperability is classified into hierarchical levels. This paper identifies application and information interactions between organizationsas a necessity for business procedures to interoperate as defined by GridWise.
Considerations for Unified Data Platform
For a Unified Data Platform we have to interface and manage information from various data sources like economic, social, regulation, policies, market, consumers, competition, organization, application, information system and technical infrastructure to name a few that needs to be interfaced to communicate and share data for analysis. An organization has numerous applications and their interactions should be ensured by an inter application protocol. Similarly, the technical interactions need to be ensured by device level protocols. The data from social, economic and policies guidelines have their own roles in interactions which regulate the sector. We must ensure that interactions between the various levels are also achieved independently. Therefore the system should allow the developer to choose standards and levels based on priorities, policies and regulations.
The emergence of Retail Competition specially after Electricity Amendment Bill 2014 which separates the carriage and content and raise fundamental questions like “Can competition for Bulk Power be replicated at retail level?”. With each Electricity Act amendment new set of data gets introduced for example Negotiated PPA Contracts in Power Markets directly between generator and distribution utilities and Short-term contracts brokered by registered traders. While the ownership of policy and regulation lies with the government, the role was mostly ignored.
In this paper we try to identify few of the data interfaces that we need to provide with the Unified Data Platform for increasing operational excellence, competition and reliability of the power sector as a whole. Some of them are listed below though this is just a indicative subset of the actual data that might go into the UDP system.
Technical Interfaces
The data from OEMs and utilities related to inputs required for production, the
Technical investments and returns
Assets not widely traded
Reduction of transaction costs
High sunk costs
Network externalities
Socio-economic and Organizational Interfaces
Necessity of centralized planning and coordination
Traditionally publicly owned but increasing private-public cooperation
Consideration of citizen right (State should assure a minimum supply)
Economic Regulation and Interfaces
Quality of services
Financial performance under public ownership
Financial performance under private ownership
Price of power generation and supply
Quantity – spectrum, banking of power
Entry & Exit policies
Investment – capacity expansion
Access to Resources – mining rights for power (coal)
Organizational Interfaces
Power sector is designed as a large network of generation, transmission and distribution units spread over huge geographical area.
Control platform for the operation of the network
Management of the distributed and areawise control centers
Comply Central Electricity and Regulatory Commission (CERC) mandate for reporting
Application Interoperability
Numerous Application interface from the control room of an utility
Interaction and storage of operating dataset
Management of applications like SCADA, Business Process and Energy Management System
Integration of data from different servers
Asset management of different hardware configurations
Software management developed by different vendors in different programming languages and different platforms
Application Interface for the unified data platform so that different applications communicate in a standard, seamless and platform independent way
Standardize services and applications using information exchange protocols
Achieve application interoperability
Manage Service Orientated Architecture and Event Driven Architecture
Design options to scale and integrate the UDP
Information Interoperability
Develop information models and protocols
Defined variable and naming schema for data storage and processing
Mapping of information exchange between devices and application
Manage multiple mapping due to different protocols, programs, platforms and systems [8].
Define standard information model to be followed by vendors
Represent all the system data like primitive data types, aggregated data types, naming schema and universally identifyable conventions
Technical Interoperability
Identify and map the physical medium of connectivity for data transfer between various devices and networks
Establish syntactic data interoperability
Manage hard wired communication networks on standard protocols for data transfer
Design scalability for future IP enabled Intelligent Electronic Device (IEDs)
Define unique identification for devices and interfaces
Regulatory
There is a need of unification of all these control centers which typically are heterogeneous in terms of hardware and software deployed. The Central Electricity and Regulatory Commission (CERC), has defined a reporting structure that mandates the utilities to coordinate and provide data from generation to transmission and finally distribution of the power.
The ULDC scheme defines a high level hierarchical organization structure which makes it easier to identify the scope of organization interoperability by considering compatibility of the equipment, standardization of hardware and software.
The Unified Data Platform (UDP) is one of the methods to achieve the above standardizations. UDP will be an information model for defining data exchange semantics between the applications of various power centers. UDP will help to achieve plug-and-play capability among the applications provided by different vendors. The vendors of various systems must comply and provide UDP adapters to make their proprietary information compatible and accessible.
In Indian power system, typically at physical level, fiber optic cables are used for inter control center communication, whereas microwave and Power Line Carrier Communication (PLCC) technologies are used for collection and transfer of data from substation RTU's to the nearest Control Center. The limitation of the micro wave and PLCC is the lower baud rate of data transfer. Above the physical medium the data transfer is achieved by the ICCP protocol [12] which is based on the 7-layer OSI communication stack. In the Indian context some efforts based on IPv6 are underway for interconnecting various networks following different proprietary SCADA protocols.
7. CONCLUSION
The role of interoperability in the Indian power system context was described with the help of a few case studies. It is pointed out that interoperability occurs at various levels. Interoperability among various systems of the power grid is crucial for achieving the benefits of standardization such as application evolution, open architecture and scalability, plug and play capability of components and services, reliability and service orientation.