The aim of this course is to introduce all of the basic principles associated with these complex systems.
The course will go into detail for the following key topics :-
By the end of the course the student will be able to identify all of the key components of a protection & control system shown above and understand how all of these components fit together to create a fully integrated system.
Electrical protection is a key element in all electrical systems, and ensures that the electrical network can operate safely and efficiently.
This second protection course will introduce you to some more protection systems, with a focus on breaker protections, transformer protection & SCADA systems.
Most substations use DC to supply the protection and control systems, so that when the main AC supply fails we can continue to monitor and control the electrical network.
In this section we will look at all of the DC systems that you will come across inside a typical transmission level substation.
By the end of the section you will know the basic architecture of a DC system, understand how the batteries are sized and operated and how the DC system is protected from earth faults.
Circuit breakers are a critical device in the electrical network as they switch power around the system, and operate quickly and securely to clear any faults on the system as they occur.
By the end of this section you will understand all about circuit breaker auxiliary switches and know what protection systems we use to ensure that the circuit breaker is operating as it should.
The circuit breaker is critical for clearing faults on the electrical system, but sometimes things go wrong and the circuit breaker fails to clear the fault.
In this section we will look at how we detect this critical situation and what actions we need to take to ensure that the electrical system is protected from collapse.
When a fault occurs on the system we trip the circuit breaker and clear it from the system. For certain types of faults and electrical systems we sometimes want to reclose the circuit breaker to get the customers connected again.
This principle is called auto-reclosure and in this section we will see how this can be achieved safely and in a controlled way
By the end of this section you will understand the sequence of events that occur during a fault, and see how timers are used to auto-reclose the circuit breaker to ensure that the customers are reconnected as quickly as possible.
When we close circuit breaker we have to ensure that the two systems we are connecting have similar parameters otherwise the circuit breaker may get damaged.
To do this we use synchronising equipment.
By the end of the this section you will understand all of the parameters that we check before closing the circuit breaker, and what equipment's and circuits we use to ensure that the circuit breaker is closed safely.
Transformers are the most expensive device that we use on the electrical network and looking after them is one of main goals when we design protection systems.
This is the first of five modules associated with transformers in this course, and we start by looking at some of the basic design features of transformers.
By the end of this section you will understand all about transformer winding types and vector groups
Transformer's are complex devices and in this section we will look in detail at how they are constructed, and what monitoring and control devices we use to ensure that they are operating correctly.
By the end of this module you will know what the inside of a transformer looks like, what effect the operation of the cooling system has on the transformer rating and what devices you will typically find on a transformer.
Transformer tapchanger's are used to alter the voltage on the network, in this section we will look at the main types of tapchanger's that we use and see how they are controlled.
By the end of this section you will understand the differences between no load and on load tapchanger's and appreciate the different control circuits that we use to operate them.
Biased Transformer differential protection is the main relay that we use to protect transformers.
By the end of this section you will understand how this relay operates and why the bias curve is so important in its operation.
In this final section on transformers we move from the theoretical side of transformer protection and start looking at how make the physical connections.
By the end of this section you will understand how we connect the current transformer when we are applying transformer differential protection relays on star and delta connected windings.
SCADA systems are used on most modern substations, to provide control and monitoring functions.
By the end of this section you will understand the architecture of the SCADA systems we use on transmission substations, see what signals are received from and are sent to the SCADA system, and understand how we connect the SCADA system to the primary plant and other substation equipment's.
Stephen Brooks is a Chartered Electrical Engineer with over 30 years experience working in the electrical utility industry, starting as an electrical design engineer before moving into the construction field as a senior project manager building high voltage substations for electrical utilities, consultants & large contractors all over the world.
I know want to use this knowledge to teach others about the lessons learned during my career and to pass on my experiences to encourage others to join the electrical power industry.