MICROGRID PROTECTIONCAPSTONE PROJECT DESIGN - DAVID LI

MICROGRID PROTECTION

DESIGN CRITERIA OF A DISTRIBUTION PROTECTION SYSTEM

▸ 3S

▸ Sensitivity: Identify an abnormal condition.

▸ Selectivity: Protection system should disconnect only the faulted part.

▸ Speed: Respond in the least possible time in order to avoid damage.

dependability security redundancy cost

MICROGRID PROTECTION

PROBLEMS IN MICROGRID

▸ Changes in the value and direction of short-circuit currents.

▸ Reduction of fault detection sensibility.

▸ Unnecessary tripping of utility breaker.

▸ Increased fault level may exceed the capacity.

▸ Conflict between feeder protection and utility requirements.

MICROGRID PROTECTION

MOST COMMON PROTECTION IN MICROGRIDS

MICROGRID PROTECTION

OVER-CURRENT PROTECTION

▸ANSI 51: Time-current discriminating capabilities.

▸ANSI 67: For the protection of ring and meshed grids.

MICROGRID PROTECTION

DISTANCE PROTECTION

▸ ANSI 21: The distance relay compares the fault current against the voltage at the relay location to calculate the impedance.

MICROGRID PROTECTION

DIFFERENTIAL PROTECTION

▸ ANSI 87: Mainly used to protect an important piece of equipment such as distributed generators and transformers.

MICROGRID PROTECTION

EXAMPLE

MICROGRID PROTECTION

ADAPTIVE PROTECTION BASED ON PRE-CALCULATED SETTINGS

MICROGRID PROTECTION

MICROGRID PROTECTION

MICROGRID PROTECTION

ADAPTIVE PROTECTION SYSTEM BASED ON REAL-TIME

MICROGRID PROTECTION

SEL - EQUIPMENTS FOR DISTRIBUTION

MICROGRID PROTECTION

SEL - EQUIPMENTS FOR SUBSTATIONS

MICROGRID PROTECTION

BIBLIOGRAPHY

▸ [1] Microgrids: Architectures and Control by Nikos Hatziargyriou

▸ [2] http://selinc.com