Switching surges, also known as transient overvoltages or switching transients, are sudden voltage spikes that occur in electrical systems when switching operations are performed. These surges can have damaging effects on sensitive equipment and can lead to insulation breakdown if not properly managed. Here are some remedial measures to mitigate switching surges:
Surge Arresters (Metal Oxide Surge Arresters):
- Surge arresters are devices installed at strategic points in the electrical system to divert and dissipate transient overvoltages.
- Metal oxide surge arresters are commonly used due to their high energy absorption capability and fast response time.
- Surge arresters provide a low-resistance path to the ground for transient surges, protecting the connected equipment.
Shunt reactors
- Shunt reactors are used to compensate for capacitive currents during switching operations, reducing the magnitude of transient overvoltages.
- They are particularly effective in high-voltage systems and can help control voltage levels during switching events.
Series capacitor
- Series capacitors can be installed in the system to control the rate of rise of transient voltages during switching.
- They are especially useful in reducing the effects of very fast transient overvoltages
Modern circuit breakers and disconnect switches
- Modern circuit breakers and disconnect switches are designed to have fast switching times, reducing the duration of transient overvoltages.
- High-speed circuit breakers can interrupt the current quickly, minimizing the impact of surges.
Grounding and bonding
- Proper grounding and bonding of electrical systems are essential to ensure that transient surges have a low-resistance path to dissipate.
- Effective grounding and bonding practices reduce the risk of equipment damage and electrical hazards.
Switching Schedules and Sequences:
- Careful planning of switching operations, including the sequence and timing of switching events, can help minimize the impact of transient surges.
- Proper coordination of switching operations with protective devices is crucial.
Training and Maintenance:
- Ensuring that personnel are trained in safe switching practices and regularly inspecting and maintaining equipment can prevent surges caused by equipment malfunctions or human error.
Summary
It’s important to note that the choice of remedial measures depends on the specific characteristics of the electrical system, including its voltage level, configuration, and the nature of the switching operations. Consulting with electrical engineers and specialists in power system protection is advisable to develop an effective switching surge mitigation strategy tailored to the system’s requirements.
