How do you design a protection scheme for a hybrid power system?

2 Protection coordination

The next step is to ensure the protection coordination among the different devices and sources in the hybrid system. Protection coordination means that the protection devices operate in a selective and timely manner, so that only the faulty part of the system is isolated and the rest remains in service. You need to consider the coordination between relays, circuit breakers, fuses, reclosers, and other devices, as well as the communication and control systems that enable the protection scheme. You also need to account for the possible changes in the system configuration, such as islanding, switching, or load shedding.

3 Protection challenges

Identifying and addressing the protection challenges that may arise in a hybrid system is the third step. These challenges include the variability and uncertainty of renewable sources, bidirectional power flow and reverse fault currents, harmonics and transients, and cyber security and resilience. To overcome these challenges, you need to use techniques and technologies such as adaptive protection, artificial intelligence, smart sensors, and cyber-physical systems.

4 Protection testing

The fourth step is to test and validate the protection scheme for the hybrid system. You need to verify that the protection devices and settings are correct and consistent, and that they perform as expected under different scenarios and conditions. You also need to evaluate the protection performance and reliability, and identify any potential issues or improvements. You can use various methods and tools for protection testing, such as simulation, laboratory testing, field testing, and online monitoring.

5 Protection standards

The fifth step is to follow the relevant protection standards and regulations for the hybrid system. You need to comply with the technical requirements and specifications that apply to your system, such as voltage, frequency, power quality, fault clearance, and interconnection. You also need to adhere to the safety and environmental standards and codes that govern your system, such as grounding, insulation, fire protection, and emission control. You can consult the national and international standards and organizations that provide guidance and best practices for protection schemes.

6 Protection benefits

The final step is to recognize the benefits of a well-designed protection scheme for the hybrid system. Such a scheme can enhance the reliability and security of the power system, improve its efficiency and economy, support the integration of renewable sources, and promote sustainability and resilience. It can do this by preventing or minimizing the impact of faults and disturbances, reducing losses and costs associated with faults and outages, facilitating connection and coordination with the grid, and enabling optimal use of diverse and clean energy sources.