Table of Contents
Introduction:
Three trends have emerged in the sphere of power automation: distributed intelligent electronic devices (IEDs), open communication, and PC-assisted HMIs. Numerical relays and computerized substation control are now state-of-the-art. The multitude of conventional, individual devices prevalent in the past as well as comprehensive parallel wiring are being replaced by a small number of multifunctional devices with serial connections.
Electricity is an extremely handy and useful form of energy. It plays an ever-growing role in our modern industrialized society. The electrical power systems are highly non-linear, extremely huge, and complex networks. Such electric power systems are unified for economic benefits, increased reliability, and operational advantages. They are one of the most significant elements of both national and global infrastructure, and when these systems collapse it leads to major direct and indirect impacts on the economy and national security. A power system consists of components such as generators, lines, transformers, loads, switches, and compensators. However, widely dispersed power sources and loads are the general configurations of modern power systems.
Block diagram explanation
Power supply unit
This section needs two voltages viz., +12 V & +5 V, as working voltages. Hence specially designed power supply is constructed to get regulated power supplies.
Buffers:
Buffers do not affect the logical state of a digital signal (i.e. a logic 1 input results in a logic 1 output whereas logic 0 input results in a logic 0 output). Buffers are normally used to provide extra current drive at the output but can also be used to regularize the logic present at an interface.
Drivers:
This section is used to drive the relay where the output is the complement of input which is applied to the drive but the current will be amplified.
Relays:
It is an electromagnetic device that is used to drive the load connected across the relay and the o/p of the relay can be connected to the controller or load for further processing.
Indicator:
This stage provides a visual indication of which relay is actuated and deactivated, by glowing respective LED or Buzzer.
Methodology:
This whole system is used to monitor the Substations of Electricity and cuts off the load in case of Earth failure, phase failure, phase reversal, etc… the power line analyzer analyses the power line and cuts off the Load in case of Earth failure, phase failure, phase reversal, etc… via monostable multivibrator. The Over/Under voltage monitors the power line and cuts off the load in case of over or under voltage conditions.
Advantages:
- High-level security for his systems and operational rationalization possibilities
- Powerful system solutions with the most modern technology
- Compliance with international standards
- Space and cost savings
- Integration of many functions into one unit and compact equipment packaging
- Simple planning and safe operation
- Homogeneous design, matched interfaces
- Rationalized programming and handling.
- Compact design and lower cost due to the integration of many functions into one relay
- High availability even with less maintenance owing to integrated self-monitoring
Disadvantages:
- One-time investment cost.
- Failure of the power line analyzer will not protect the Load.
Applications:
- All devices and systems for protection, metering, and control mentioned herein are designed to be used in the arduous environment of electrical substations, power plants, and various industrial application areas.
