Sohar Aluminium Company, Oman

One of the largest aluminum smelter facilities in the world, Sohar Aluminium produces more than 360,000 tons of aluminum annually and is also one of the biggest power consumers in Oman. The smelting process was creating high levels of harmonics and it was imperative to keep these under control to adhere to the grid codes and be connected to the Oman power grid without any compliance issues.

Harmonics are akin to electrical pollution created by non-linear loads. If harmonics in a network are too high, it can result in forced aging as well as overload and tripping of electrical equipment. High harmonics also interfere with the smooth operation of electronic equipment like computers and UPS systems and create an increase in network losses. Many utilities impose penalties for non-compliance with harmonic regulations and grid codes.

Hitachi Energy delivered a turnkey solution to Sohar Aluminium, including a study of the harmonics in the plant as well as the design, supply, installation, testing and commissioning of a harmonic filter system. The power quality solution comprises four harmonic filter banks at 55 Mvar and high-voltage switchgear.

The filter system has solved power quality issues with regard to harmonics and reactive power and allows Sohar Aluminum to connect to the Oman grid without any compliance issues. The system has also improved power quality in the smelter facility and reduced electrical losses.