Incorporating Sensors Into Medium Voltage Substation Applications

The energy sector is rapidly changing – presenting new challenges every day. In the past, the flow of energy from a single, large powerplant to the end user was unidirectional; today, the industry is seeing multiple energy producers – including small power plants, wind and solar farms – generating energy all over the grid and delivering it bidirectionally to the end user.

These changes have made it increasingly important for professionals in the industry – especially those looking toward more renewable practices – to monitor their energy production through online systems. While it’s true that the fragmentation of energy producers across the network makes monitoring necessary, there is a range of smart solutions available which professionals can utilize to manage their energy production, distribution and transmission more effectively.

Take sensor devices, for instance, which can be used to efficiently measure physical quantities – such as voltage, current, temperature, or humidity – and respond quickly with feedback. Once the physical device creates a signal, the data can be read on a multitude of software programs. Innovations in these types of products have, ultimately, been born out of the recent changes in energy production – providing the next generation of data-driven technology.

Changes to the substations themselves have also increased demand for new solutions. For years, substations depended on air insulation to reduce problems associated with flashover – relying on the distance between live and ground components being great enough to negate these issues. However, advancements in technology have enabled substations to become increasingly more compact. While reducing the size does make the substation safer and less affected by environmental influences, it also means that air insulation is no longer possible, as live and grounded parts are now closer together.

To solve this insulation challenge, utilities have turned to screened solutions to prevent live and ground parts from interacting and causing flashovers. This need for screened solutions has led manufacturers, including TE Connectivity (TE), to develop a range of separable connectors using different measurement technology like capacitive and resistive devices.

How can separable connectors and sensors work together?

Separable connectors are among the first products on the market to enable sensors to monitor substations. These medium voltage components have been engineered to optimize performance and solve switchgear and transformer connection challenges in IEC, IEEE and GB/T power grids.

In terms of electrical installation, separable connectors themselves are easy to install. The innovation lies in the modular design of the products, which consist of multiple, customizable pieces that can be adapted depending on the required application – even allowing for the simultaneous use of multiple separable connectors. This advanced design ensures the products can easily, safely and quickly be installed and connected to integrated devices above ground, while at the same time keeping the device separate from the application itself.

Watch: Separable Connector installation video

Furthermore, as sensors may require attention over their lifetime, it is optimal for all sensor components to be accessible for maintenance and recalibration to guarantee reliability. Separable connectors add an additional element of convenience because they are installed above ground, naturally allowing for easy access. The sensors incorporated into these products enable measurements to be automatized and reporting to be both immediate and consistent within substations.

Adapting designs to meet shifting requirements

From an application standpoint, TE RSTI separable connectors with a type C outer-cone bushing have become a common connection on distribution networks -, and already boast a reliable reputation. . The main application for these separable connectors with sensors is energy distribution for ring main units.

Over the years, energy density on these networks has required some modification to extend the range of this type of bushing from 630 A to 1250 A rated current. As a result, TE has adapted the separable connector design to cope with this requirement to enable the full current carrying capabilities of the connection between the cable, bushing and separable connector. In March 2018, TE launched the next generation of 250 A screened separable connector, designed to connect single-core polymeric cables to medium voltage gas insulated switchgears and other equipment using type “A” bushings.

Currently on the market are TE’s Raychem RSTI screened separable connectors, which have been designed to connect single and three-core polymeric cables to medium voltage gas insulated switchgears and other equipment using type C bushings. Made of a highly modified silicone rubber and protected by a thin-walled outer conductive screen connected to earth, TE’s connectors are equally suited for indoor and outdoor installation.

Technology is becoming a commodity in the current market

In the last 15 years, and particularly over the last five years, the market share of connectors has been growing successfully at a steady pace – a direct result of the substations becoming smaller and more compact. This indicates a rising trend worldwide, with both the mature markets such as Europe, and the emerging markets in the Middle East and Africa – where, up until recently, air-insulated terminations were used extensively – now being pushed towards solutions like separable connectors.

At the same time, the new trend of incorporating sensors with separable connectors is an exciting development – one which presents various opportunities for energy professionals and organizations alike. In the current market, technology is increasingly becoming a commodity – as proven by these growing trends.

To find out more about TE’s extensive range of customizable products and separable connectors, please visit: http://www.te.com/global-en/products/power-systems/power-cable-accessories/separable-connectors.html?source=header-match&tab=pgp-story