Remote Terminal Unit for Wireless SCADA Systems

When it comes to the management of energy systems, optimal design plays a key role. The project that’s going to be described in this post relies on the usage of Supervisory control and data acquisition (SCADA) systems along with remote terminal unit.

The design has a large scale development of remote terminal unity which is an important part of the SCADA system. The focus of the design can be varied using Programmable Logic Controller (PLC) or the Field Programmable Gate Array (FPGA).

The benefit of using FPGA based remote terminal units is that the designer gets better encryption, radio and memory support. The innovation achieved in this model is similar to the that of the Rogowski coil and other similar models.

The SCADA system requires field data interface devices which are referred to as the remote terminal unit or RTU. The RTU is able to transfer the data from the interface devices to control units. The interface is known as Tele control interface (TCI). The master terminal unit or MTU is a server collection that allows simulations to run.

The development of low cost RTU design would allow better management of electricity in energy deficit areas.

For optimizing the design, a FPGA development kit can be used. This design can be then be employed in wireless SCADA. The kit is derived from XILINX Spartan 3 Series FPGA which has 500000 logic gates. The imagery provided below would give the data about:

  • –  16 channels Digital Input
  • –  8 channels analog input
  • –  8 channels relay output RTU board


The 32 I/Os based configuration is used to make the optimized design. With regards to the performance, FPGA based RTUs are more power friendly. The mainstream features of this design are:

  • –  The FPGA design is more flexible in the case of I/Os and CPU related configurations. The expansion can be also accommodated if required.
  • –  This design is more intelligent and is highly relevant to applications in power management. So optimized alarms can allow the efficiency of the system to improve.
  • –  Another major benefit is that the industrial temperature range of this circuit is from -40 to 100 oC. This shows the ability to sustain harsh environment conditions.
  • –  With respect to the network, the optimized design can work with third generation SCADA which mostly relies on a network approach.
  • –  With reference to the RAM, it is 72 KB/648 KB better than the 32KB/256KB of PLC based RTU.
  • –  Remote system diagnostics can also be run which was not available before. In the same way, digital clock managers can also be employed.

As far as the data communication is concerned, it would be achieved through the TDMA method. The principle is quite straightforward. The sensors would carry the data to FPGA (to its processing section) along with the RTU concept implementation. The second part of the management information system would be achieved through the TCI module. In this way, two types of communication modules can be generated:

  • –  Indoor communication system (among RTUs)
  • –  Outdoor communication system (among remote sites)

The proposed design in this project is an optimized solution for energy management. It also targets the shortcomings of the traditional PLC-RTUs. The design is reconfigurable, making it an easily adopted model.

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  1. Not able to connect to the concerned website for detail reading through READ

  2. If [read] refers to same article, then either article is full or look for related links inside post. Take a look at Tutorials section. Same here.

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