Abstract
The strong focus on global warming the recent years has
contributed to a change towards a more climate friendly
and energy efficient energy system. New energy efficient
electrical appliances have clearly shown to be a challenge
in the Norwegian distribution system and in the low voltage
network in particular. These types of electrical loads have
shown to increasingly often cause voltage disturbances
exceeding the quality limits in both the EN50160 [1] and
the Norwegian voltage quality regulations [2]. This have
shown to cause everything from only irritation among
customers based on poor lighting quality to malfunction
and trip of electrical equipment.
Estimates made by Norwegian network operators indicate
that the necessary network reinforcement investments in
Norway are in the range 2 to 12 billion Euros if all
customers are being allowed to install and use the most
challenging electrical appliances. These challenges will
probably be similar in other countries if not necessarily as
large as in Norway. Performed investigations indicate a
high percentage of low voltage networks in Norway with
relatively low short circuit capacity as between 40 and 50
% of the low voltage networks seem to have a higher
impedance than the European reference impedance.
Norwegian Distribution System Operators (DSOs) are
raising the question whether all electric appliances should
be treated as "normal" equipment that can be used
unconditionally or whether there is a need for changes in
the rules for what equipment the DSOs must be notified
about before the load is connected and used.
contributed to a change towards a more climate friendly
and energy efficient energy system. New energy efficient
electrical appliances have clearly shown to be a challenge
in the Norwegian distribution system and in the low voltage
network in particular. These types of electrical loads have
shown to increasingly often cause voltage disturbances
exceeding the quality limits in both the EN50160 [1] and
the Norwegian voltage quality regulations [2]. This have
shown to cause everything from only irritation among
customers based on poor lighting quality to malfunction
and trip of electrical equipment.
Estimates made by Norwegian network operators indicate
that the necessary network reinforcement investments in
Norway are in the range 2 to 12 billion Euros if all
customers are being allowed to install and use the most
challenging electrical appliances. These challenges will
probably be similar in other countries if not necessarily as
large as in Norway. Performed investigations indicate a
high percentage of low voltage networks in Norway with
relatively low short circuit capacity as between 40 and 50
% of the low voltage networks seem to have a higher
impedance than the European reference impedance.
Norwegian Distribution System Operators (DSOs) are
raising the question whether all electric appliances should
be treated as "normal" equipment that can be used
unconditionally or whether there is a need for changes in
the rules for what equipment the DSOs must be notified
about before the load is connected and used.