Generally , plants run synchronously with the grid because there is always some mismatch between power generation and demand . Also , if due to some reason , a power plant trips , it will require starting power that can be drawn from the grid . But usually , plants have their islanding mode enabled , which will automatically island or iso late the plant if there is some external disturbance in the grid , such as a voltage dip or erratic frequency change , thus , protecting the plant from external disturbance .
In the grid-connected mode , the host grid handles frequency and voltage regulation . However , in an islanded operation , a microgrid must regulate internal frequency and voltage with proper control . Droop control is the commonly accepted operation for power sharing among DERs ( distributed energy resources ) in a microgrid .
ACTOM offers a complete turnkey power island solution and is a leading supplier of premium specifications and standard lowvoltage motors , gearboxes , speed reducers and mo tor starters . The company custom designs and manufactures medium voltage motors for the mining , industrial , processing and utility markets in South Africa and globally .
Naidoo says , “ We can deliver every element of a power island . We manufacture the boiler , the turbine , the generator , and the associated switchgear and control .” Here , the 12 company divisions combine and deliver an integrated solution within an efficient value chain .
John Thompson , a division of ACTOM ( Pty ) Ltd , having had a long history and many a success story involving their unique boiler design and manufacturing , is a global leader in energy and environmental solutions through value engineering and innovation .
The division focuses on serving their global customers with tailormade boilers , environmental solutions ( including Air Pollution Control ), engineering , energy management , manufacturing , spares , maintenance and training , and they specialise in generating power for sugar mills . Their engineering teams can accurately simulate virtually any scenario using the latest computational fluid dynamics technology .
When maintenance is needed , ACTOM ’ s electro-mechanical maintenance , service and repairs specialist , Marthinusen & Coutts , include the maintenance and servicing of machin ery and equipment for the mining , rail transportation , utilities , marine , and oil and gas industries .
The company is a specialist repairer of power generation equipment , medium and low voltage AC and DC motors , transformers and coil manufacture , and the full range of engineering , testing , diagnostics , balancing and maintenance services .
A power island would not be complete without an IoT solution . ACTOM uses loT devices and artificial intelligence to provide tailormade solutions to their customers through visibility in the process .
The company digitises factories , and equipment and design programs which include applications in protection and control and static power . Incorporating smart intelligence so that equipment enables an increase in productivity and factory efficiency and a reduction in downtime and wastage .
Static Power specialises in the design and manufacture of AC and DC standby equipment for the industrial , telecommunications , rail and renewable energy markets , including thyristor type chargers ( micro process controlled options ), industrial batteries , power supplies , industrial UPS , furnace control panels , AC / DC distribution boards and battery tripping units . Static Power has embarked on turnkey solutions for renewable energy and battery energy storage solutions – all designed and engineered to suit their purpose for local and export markets .
The company ’ s success stories are evident in completed projects and efforts to keep the lights on .
Biomass fuel plants The Ngodwana Biomass Fuel Plant biomass power plant installation , established under South Africa ’ s Independent Power Producer Programme , was completed as a joint venture between John Thompson ’ s Industrial Watertube Boilers , an ACTOM division – and Lesedi Nuclear Services . The 25MW power plant is adjacent to Mpumalanga ’ s Sappi Ngodwana pulp mill . According to Russel Warren , general manager of John Thomson , the installation took 20 months . John Thomson will operate and maintain the entire plant , comprising the boiler , turbine , and balance of the plant , over a fiveyear contract period .
Wind farms ACTOM Power Transformers hasdesigned several low-cost transform ers for wind farms , including 157 x 2 700kVA padmounted , oil-natural , and air-natural transformers . Consolidated Power Projects , the electrical BOP contractor for the wind farms , Noupoort , Khobab and Loeriesfontein , ordered their transformers from ACTOM . The company had previously also supplied the Kouga Wind farm project . Newer transformers also accommodate the load-break switch and current limiting fuses inside the transformer tank by mounting them under oil instead of the usual external arrangement applied to package transformers . This reduces the cost . The company supplies electrical equipment , services and ‘ balance of plant ’ to any renewable energy projects .
The Nordex Kouga Wind Farm in the Eastern Cape is a renewable energy project which makes the most of the fresh onshore breezes that sweep the Eastern Cape coastline of South Africa . Nordex engaged South African contractors Power Construction and ACTOM to undertake the civil and electrical work .
Hydropower plants Marthinusen & Coutts is Africa ’ s largest after-market service provider of electrical and mechanical rotating machines . The division works extensively on hydropower plants and has recently been contracted to refurbish a synchronous condenser at the Inga River hydro project in the DRC .
Naidoo adds , “ ACTOM is involved in many power projects in the African market , including pump storage schemes like Ingula and the Drakensberg Pump Storage scheme . This reaffirms ACTOM ’ s position in the whole power island supply chain .”
“ ACTOM offers the complete engineering , procurement and construction value chain to the installation of the plant , and then beyond that , the actual operation and maintenance of the plant . We take the subcomponents from the cradle to the grave , where we have the after-market services and repairs capability . The company can manufacture all these products and support them through their full life-cycle and ultimately facilitate the customer in receiving an optimised plant performance ,” Naidoo concludes .
Local manufacturers offer a unique value chain of services when it comes to renewable power generation and solutions . •
1 . Source : ACTOM
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