This guide applies to voltage and reactive power control in 1000 kV and above ac systems. It establishes criteria and requirements for electric power utilities in the planning, design, infrastructure, operation, and scientific research of voltage or reactive power in 1000 kV and above ac systems, which should guarantee the system stability and equipment safety.

This guide identifies basic principles for voltage regulation and reactive power compensation. This guide also provides acceptable voltage deviation limits range, as well as technical measures for voltage and reactive power adjustment and allocation in power systems at 1000 kV ac and above.

This guide identifies voltage regulation and reactive power compensation recommendations for users involved in the planning, design, construction, and operation of power systems at 1000 kV AC and above. This guide may also be used for the purpose of scientific research.