It connects the 3,000 MW coal-based Rihand Thermal Power Station in Uttar Pradesh to the northern region of India.
On 24 June 1990, during the commissioning of the scheme, a complete quadrivalve of the Rihand converter station was destroyed, and the other two quadrivalves of the same pole badly damaged, by a fire which is believed to have started as a result of a loose connection on a grading capacitor.
The fire was so intense that the valve hall was structurally damaged, and the affected converter was out of action for 18 months.
Similar incidents on the Itaipu project in 1989 and the Sylmar Converter Station of the Pacific DC Intertie scheme in 1993 led to CIGRÉ publishing guidelines on the design of thyristor valves in order to reduce fire risks.
[1] In 1996 the National Fire Protection Association published NFPA 850{2} to further enhance fire prevention and protection guidelines base on input from the HVDC manufacturers and utility owners.