A dispatcher training simulator (DTS), also known as an operator training simulator (OTS), is a

computer-based training Educational technology (commonly abbreviated as edutech, or edtech) is the combined use of computer hardware, software, and educational theory and practice to facilitate learning. When referred to with its abbreviation, edtech, it often refer ...

system for operators (known as dispatchers) of electrical power grids. It performs this role by simulating the behaviour of the

electrical network An electrical network is an interconnection of electrical components (e.g., batteries, resistors, inductors, capacitors, switches, transistors) or a model of such an interconnection, consisting of electrical elements (e.g., voltage sources, c ...

forming the power system under various operating conditions, and its response to actions by the dispatchers. Student dispatchers may therefore develop their skills from exposure not only to routine operations but also to adverse operational situations without compromising the security of supply on a real transmission system.

Description

Early simulations modelled the transmission system with banks of

analog computer An analog computer or analogue computer is a type of computer that uses the continuous variation aspect of physical phenomena such as electrical, mechanical, or hydraulic quantities (''analog signals'') to model the problem being solved. In c ...

s linked by scaled-down representations of the interconnecting lines. The operator would simulate the operation of circuit breakers by physically operating their miniature replicas. As transmission systems grew in size and complexity, they could no longer be adequately represented in this manner, and computerised simulations came to the fore. A modern DTS combines or simulates the following elements: * An

energy management system An energy management system (EMS) is a system of computer-aided tools used by operators of electric utility grids to monitor, control, and optimize the performance of the generation or transmission system. Also, it can be used in small scale syste ...

(EMS): a computer system for controlling a

power grid An electrical grid is an interconnected network for electricity delivery from producers to consumers. Electrical grids vary in size and can cover whole countries or continents. It consists of:Kaplan, S. M. (2009). Smart Grid. Electrical Power ...

. The EMS enables remote operation of electrical equipment, such as

circuit breaker A circuit breaker is an electrical safety device designed to protect an electrical circuit from damage caused by an overcurrent or short circuit. Its basic function is to interrupt current flow to protect equipment and to prevent the risk ...

s or

transformer A transformer is a passive component that transfers electrical energy from one electrical circuit to another circuit, or multiple circuits. A varying current in any coil of the transformer produces a varying magnetic flux in the transformer' ...

s. It also receives information transmitted back to an electricity control centre, such as the status of equipment or notification of alarms. The

user interface In the industrial design field of human–computer interaction, a user interface (UI) is the space where interactions between humans and machines occur. The goal of this interaction is to allow effective operation and control of the machine f ...

typically displays the state of the transmission system on computerised

one-line diagram In power engineering, a single-line diagram (SLD), also sometimes called one-line diagram, is a simplest symbolic representation of an electric power system. A single line in the diagram typically corresponds to more than one physical conductor: ...

s with controllable points for simulated operation of plant such as

s or transformer tap-changers. * A

SCADA Supervisory control and data acquisition (SCADA) is a control system architecture comprising computers, networked data communications and graphical user interfaces for high-level supervision of machines and processes. It also covers sensors and ...

(Supervisory control and data acquisition) system, which provides collection and assimilation of data from substations and transmits operator instructions back to the same plant. * A load-flow study to calculate power flows and voltages on the transmission system and to model its responses to disturbances such as line trips,

relay A relay Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts An automotive-style miniature relay with the dust cover taken off A relay is an electrically operated switch ...

action, and

generator Generator may refer to: * Signal generator, electronic devices that generate repeating or non-repeating electronic signals * Electric generator, a device that converts mechanical energy to electrical energy. * Generator (circuit theory), an eleme ...

demand In economics, demand is the quantity of a good that consumers are willing and able to purchase at various prices during a given time. The relationship between price and quantity demand is also called the demand curve. Demand for a specific item ...

mismatch. The model will normally extend to the limits of the system operator's region of interest, and include representations of plant such as

lines Line most often refers to: * Line (geometry), object with zero thickness and curvature that stretches to infinity * Telephone line, a single-user circuit on a telephone communication system Line, lines, The Line, or LINE may also refer to: Arts ...

, generators,

s and

capacitor A capacitor is a device that stores electrical energy in an electric field by virtue of accumulating electric charges on two close surfaces insulated from each other. It is a passive electronic component with two terminals. The effect of ...

s. Optionally the subtransient behaviour of the system can also be modelled. * The system may additionally provide facilities for modelling and optimising the

economic dispatch The merit order is a way of ranking available sources of energy, especially electrical generation, based on ascending order of price (which may reflect the order of their short-run marginal costs of production) and sometimes pollution, together w ...

of generating units. Any generation's dynamic characteristics and limits, in particular its

voltage regulation In electrical engineering, particularly power engineering, voltage regulation is a measure of change in the voltage magnitude between the sending and receiving end of a component, such as a transmission or distribution line. Voltage regulation desc ...

, maximum generation, and rate of change of output are usually incorporated.

Operation

A DTS is frequently purchased by a customer (such as a

transmission system operator File:Electricity grid simple- North America.svg, 380px, Simplified diagram of AC electricity grid from generation stations to consumers rect 2 243 235 438 Power station rect 276 317 412 556 Transformer rect 412 121 781 400 Electric power transmis ...

) at the same time and from the same manufacturer as an

, and is usually designed to mimic it as closely as possible. Operational scenarios are created on the DTS to represent the operator's transmission system under a variety of conditions. These may represent normal operating conditions, or be specially designed to test the student's responses to adverse circumstances, such as frequent line trips during severe weather. The DTS is administered by a team of instructors, who select scenarios and simulate operational events, monitoring the trainee's actions in response. Scenarios may also represent circumstances that the system operator hopes never occur, such as complete system shut-down, and allow it to develop strategies for restoration of service (known as

black start A black start is the process of restoring an electric power station or a part of an electric grid to operation without relying on the external electric power transmission network to recover from a total or partial shutdown.Knight, U.G. ''Power ...

). Deficiencies in operator training were identified as a contributory cause of the

2003 North American blackout The Northeast blackout of 2003 was a widespread power outage throughout parts of the Northeastern and Midwestern United States, and most parts of the Canadian province of Ontario on Thursday, August 14, 2003, beginning just after 4:10 p.m. ...

, a factor similarly connected to earlier power failures. The joint US-Canadian task force investigating the incident recommended mandatory periods of simulation time for operators, and validation of the models against actual system characteristics. To enable the training simulator to respond as realistically as possible to the student's actions, the power flow study at its heart must run on a frequent time basis, such as every few seconds. The simulation may model electrical networks consisting of many thousands of nodes and containing several hundred generating units.

References

{{Reflist Electric power transmission Industrial computing