Applications of SCADA systems in Electrical


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SCADA systems can be made use to have Graphical user interface (GUI) system. GUI system can be used to have maps, graphical representation of the required area, and graphical representation of required data.

Using SCADA these maps can be layered, zoomed, scrolled and planned. The historical data of the machine can also be used.

Applications of SCADA systems in

The various application programs that can be implemented using SCADA systems are clearly explained here. The following are the applications that can be used for remote monitoring, control, safety, efficient utilization of resources etc.

Fault location, isolation and Service Restoration:

This function determines alternate paths for restoring service to the affected load points due to a fault on a section of the feeder considering current loading conditions.

Most of the rural feeders do not have an alternate supply for service restoration. In urban areas, many alternate paths are available to a feeder; therefore, this function will be more effective.

To implement this function, load switches or sectionalizer are needed at selected feeder locations. Earlier, sectionalizer were air-break switches without any remote-control features. All such switches should be replaced with remotely controllable switches.

Maintaining good voltage profile

This function controls the capacitor banks and voltage regulators to provide a good voltage profile in the distribution feeders.

An appropriate schedule for switching on/off of capacitor banks and raise/lower voltage regulator taps was based on the feeders’ reactive load curves in order to get good voltage profiles and reduce energy losses.

Load Balancing

This function distributes the system total load among the available transformers and the feeders in proportion to their capacities.

As explained above, there was a need to replace the existing switches with remotely controllable switches in order to reconfigure the network for load balancing.

Load Control

Load Management Function is divided into three categories:

(a) During summer there is usually a generation shortage. Therefore, loads need to be shed for long durations. A restriction and control schedule is worked out based on which of the loads at different substations are shed on a rotation basis. This function will automatically shed the loads according to the schedule. Provisions to change the schedule are also provided.

(b) Emergency Based Load Shedding: During emergencies, the utility needs to shed some load to keep up the balance between generation and demand. Instructions are sent to respective substations to shed load.

Based on the amount of relief requested, the operator would select some loads and shed them. This function will help to identify loads to be shed considering their priority, time when they were last shed and the duration of the last interruption to ensure that only the required amount of load shedding is done.

© Agricultural Pump Control -Agricultural loads are categorized into groups. This function controls the agricultural loads automatically, based on predefined schedule. Provision to change schedules is also provided.

(d) Frequency-Based Automatic Load Shedding:-In this implementation, frequency-based automatic load shedding is carried out by software using this function. Appropriate loads are shed by the RTU, based on priorities and actual amount of load whenever the system frequency crosses the pre-set values.

This is done as a closed loop function in the RTU. To sense system frequency, high-response-time (about 200 m.sec) frequency transducers are required. Presently it has been difficult to find such high-response-time frequency transducers.

Remote metering

The function of remote metering is to read data from the meters and to provide information to the operator of the consumption patterns of the high-value HV customers.

Its main feature is to provide a multiple tariff to the customers to encourage them to shift their loads from peak times to off-peak times. This function also provides meter-tampering detection

Fuse-off-call operations

This consumer-aid application function responds to complaints from consumers. It has the following features: Accepts interruption/restoration data from the operator. Accepts DT trip/close information from SCADA.

Identifies the interruption source whenever possible and gives information on the outage effects to the operator. Displays status of energized /de-energized status of the consumer. This function will improve the response time to the consumer complaints.

Energy accounting

This function helps in arriving at the system’s load patterns, which helps in planning expansion. It also helps in detecting abnormal energy consumption patterns of the consumers and identifying high-loss areas.

Processing the data obtained by the remote metering function and the data obtained from the substation does this.