Botswana Power Corporation
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Electric utilities must reduce costs while ensuring operational excellence, rapidly digitise end-to-end processes and improve performance. They also face the risks of balancing demand peaks with low intermittent production. This is where automation and technical applications play a critical role in advancing the energy network’s resilience.

The use of technical solutions improves automation and promotes intelligent networks within the utility business, which allows for new business models and new customer services to advance the utility beyond its reliance on electricity sales.

Each component of the power network can be optimised for a modern, automated network and Schneider Electric has designed its products and services to assist utilities down this path.

This article first appeared in ESI Africa Edition 4, 2018. You can read the full digital magazine here or subscribe here to receive a print copy.

According to Taru Madangombe, vice president of energy in southern Africa for Schneider Electric, the energy supply industry in South Africa is experiencing a new dawn, where conversations on relevant topics such as digitalisation, decentralisation, grid maintenance and management, energy efficiency and industrial applications, renewable energy systems, energy storage, demand management, communications and automation for infrastructure are taking place.

As such, Schneider Electric strives to ensure that ‘Life is On’ for the rural and urban infrastructures of the continent through the application of its specialised product knowledge and the Industrial Internet of Things (IIoT), explains Madangombe.

A solution to advance network capability

Schneider Electric’s E-Series solid dielectric Automatic Circuit Recloser (ACR) represents the company’s commitment to invest in product development. It provides the benefit of upto-date design optimised for automation, remote control and monitoring, now or in the future. After careful evaluation of customers’ needs, the E-Series was developed to achieve performance using technology in solid dielectrics, vacuum interruption and microelectronics.

The E-Series circuit breaker is controlled and monitored by the advanced monitoring and control (ADVC) module. ADVC is enclosed in a 316-grade stainless steel enclosure, which provides an electronic controller with Operator Interface (O.I.) that monitors the circuit breaker and performs protection, measurement, control, and communication functions. The switchgear circuit breaker and ADVC are connected via a control cable and they form a remotely controlled and monitored ACR.

The switchgear is operated by a magnetic actuator, which produces an opening and closing action. Switching occurs when a controlled pulse is sent through the open/close actuator from storage capacitors in the ADVC. When closed, the switch is latched magnetically. Spring loaded push-rods provide contact loading on the interrupters.

Current transformers and resistive voltage dividers are moulded into the epoxy-housing. These are monitored by the ADVC for protection, remote monitoring, and network status display. An auxiliary voltage supply of 115/230V AC is required to power ADVC. Where this is inconvenient, an additional voltage transformer can be provided. Mounting brackets for lightning arresters are optionally available. The switchgear contact position is shown by a large, clearly visible On/Off indicator.

The ACR is fitted with a mechanical trip ring, which allows for normal operation, manual tripping and locking the recloser in open position.

The E Series ACR is type tested in accordance with IEC standards for the following characteristics:

  • Rated maximum voltage 38kV
  • Rated continuous current 800A
  • Short time withstand current 16kA
  • Rated lightning impulse withstand voltage 170kV
  • Circuit breaker class M2 & E2

A tool with a list of credits 

The E-series recloser brings various benefits to the electrical distribution networks in South Africa and even beyond its borders. These include:

Reduced purchase costs

  • No requirement for additional Remote Terminal Unit (RTU), power supplies, batteries, or enclosures. The RTU and a range of communication ports are included in the standard equipment.
  • Schneider Electric ACRs are suitable for feeder circuit breakers in outdoor primary substations.

Reduced installation costs

  • Simple commissioning: Configuration of the unit can be done via Windows Switchgear Operating Software or O.I.
  • Optimal design for pole mounting brackets and an optional voltage transformer for auxiliary supply Reduced operating costs
  • Reduced equipment damage and low maintenance equipment reduces operating cost.
  • ACR is integrated with current and voltage sensors without the need for additional measurement devices.

Smart grid ready

  • With the increasing push for advanced monitoring, reduction of outages and the need to facilitate two-way communications between supply and the distribution network, the E-Series solid dielectric recloser is ready to be integrated into your Smart Grid solution.
  • When used with a compatible Advanced Distribution Management System (ADMS or DMS), Schneider Electric ACRs support seamlessly remote control and monitoring.

Take the next step with an innovative partner

“Digital and automation solutions – such as Schneider Electric’s Advanced Distribution Management Systems (ADMS), which combines the Distribution Management System (DMS), Outage Management System (OMS) and Supervisory Control and Data Acquisition (SCADA) system into one comprehensive network management solution – are used globally by electrical utility providers and municipalities to give them more visibility to be able to better manage their revenue and network performance,” says Madangombe.

Highlighting innovative technological advances, another Schneider Electric solution was recently installed at the Stubb Street Substation in Makhado (Louis Trichardt), Limpopo Province, South Africa with the first of the newgeneration Schneider Premset SSIS (Shielded, Solid Insulation System) modular switchgears.

“This represents the future of medium voltage distribution, embracing intelligent connectivity to bring a new level of efficiency to help meet the growing demand for power, especially for critical power industries in need such as data centres, utilities and healthcare,” he concludes. ESI

This article first appeared in ESI Africa Edition 4, 2018. You can read the full digital magazine here or subscribe here to receive a print copy.


About the company

Schneider Electric is leading the digital transformation of energy management and automation in homes, buildings, data centres, infrastructure and industries. With global presence in over 100 countries, Schneider is the undisputable leader in power management – medium voltage, low voltage and secure power, and in automation systems. www.se.com