PLC based Substation Automation and Control : development of plc based solution for measurement, control, alarm and monitoring in distribution substations
Vellore Farooq, Azeez Ahmed (2025)
2025
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2025121838251
https://urn.fi/URN:NBN:fi:amk-2025121838251
Tiivistelmä
The need for automation and control solutions for substation equipment is of utmost importance and it is a critical need in the utility sector. Predominantly, the substations are in remote locations and unmanned for most of the time during their lifetime in operational service. With the exponential growth in demand for electricity there is a need to modernize the existing electrical systems with automation and control systems for efficient and safe operation of the substation. The available solutions and products enabling these features are of complex design and requires huge initial investment. Hence, there is a need to explore other alternative low cost, simple and effective solutions which can deliver the task for Substation Automation and Control.
There are several systems and solutions available across the market to address this topic, however the selection of the suitable solution requires several factors to be considered, the key factors among them are the compatibility, cost and simplicity of the proposed automation solution. The use of Programmable Logic Con-troller (PLC) is one of the solutions which will be explored in this research task. PLC’s have excellent features and is proven for their ruggedness, scalability, flexibility and low cost. PLC’s have been employed in Industrial applications for many decades with proven reliability and are well proven across wide variety of applications.
The focus of the thesis work is to explore and develop PLC based application solutions and hardware selection for performing Measurement, Control and Monitoring functions in a distribution substation. The work in-volves selecting suitable analog modules for current and voltage measurements as well as monitoring digital signals for alarms, events and control functions for the substation equipment’s such as Circuit Breakers, Dis-connectors and Earth Switches. Although these features are already offered in protection IED’s by various well-known manufacturers for substation applications for advanced Monitoring and Control functions. How-ever, given the fact that these IED’s are costly solutions requiring huge investment, the PLC offer low-cost alternative to deliver the desired functions. The scope of the work is mainly focused on application of the proposed solution in existing and old medium voltage distribution substations where there is a need to modernize and upgrade the automation and control systems in place of manual operation control.
It is desired that the thesis outcome would be a proposed idea providing a basic design and solution for implementing PLC and compatible distributed I/O’s for monitoring and control functions for medium voltage substation feeders. The method and logic behind the selection of suitable PLC solutions will be generic and follows common practices and requirements applicable in a typical substation.
Note: The protection functions of the substation are not addressed in this research work and will not be a part of this thesis work, as this is taken care of by existing relays and other protection devices.
There are several systems and solutions available across the market to address this topic, however the selection of the suitable solution requires several factors to be considered, the key factors among them are the compatibility, cost and simplicity of the proposed automation solution. The use of Programmable Logic Con-troller (PLC) is one of the solutions which will be explored in this research task. PLC’s have excellent features and is proven for their ruggedness, scalability, flexibility and low cost. PLC’s have been employed in Industrial applications for many decades with proven reliability and are well proven across wide variety of applications.
The focus of the thesis work is to explore and develop PLC based application solutions and hardware selection for performing Measurement, Control and Monitoring functions in a distribution substation. The work in-volves selecting suitable analog modules for current and voltage measurements as well as monitoring digital signals for alarms, events and control functions for the substation equipment’s such as Circuit Breakers, Dis-connectors and Earth Switches. Although these features are already offered in protection IED’s by various well-known manufacturers for substation applications for advanced Monitoring and Control functions. How-ever, given the fact that these IED’s are costly solutions requiring huge investment, the PLC offer low-cost alternative to deliver the desired functions. The scope of the work is mainly focused on application of the proposed solution in existing and old medium voltage distribution substations where there is a need to modernize and upgrade the automation and control systems in place of manual operation control.
It is desired that the thesis outcome would be a proposed idea providing a basic design and solution for implementing PLC and compatible distributed I/O’s for monitoring and control functions for medium voltage substation feeders. The method and logic behind the selection of suitable PLC solutions will be generic and follows common practices and requirements applicable in a typical substation.
Note: The protection functions of the substation are not addressed in this research work and will not be a part of this thesis work, as this is taken care of by existing relays and other protection devices.