Voltage Flicker Analysis and Solution
The voltage flicker is a phenomenon of unstable voltage
resulting in poor performance of the lighting and other voltage sensitive
loads. The voltage flicker occurs as result of randomly changing reactive power
demand of the random process loads. Examples of such loads are
- Electric arc furnace loads
- Rolling mill loads
- Large induction motor starting with long starting time
- Large synchronous motors started as induction motors
- Unbalanced and fluctuating loads
Typical solution involve providing necessary reactive power
support as close to the loads causing the flicker, and thus preventing the rest
of network experiencing from voltage flicker phenomenon. The reactive support system,
will need to measure the reactive power demand from the loads and initiate a
control to provide necessary reactive power support. Static Var Compensators , STATCOMs,
and even simple fixed capacitors [where fluctuation is temporary] are some of
the devices used to achieve desired reactive power support and mitigation of the
voltage flicker phenomenon.
We provide simulation based recommendation on the sizing and
type of reactive power compensation based on the load profile as function of
time. The simulation will use both static load flow solutions and dynamic time
domain simulations and capture the impact of the randomly varying loads on
other system loads, flows, voltages. The various options for the solution to
mitigate the flicker problem will be evaluated through simulation and
recommendations will be provided on sizing, location and type of reactive power
support needed to mitigate the voltage flicker problems.