The load-shedding solution ensures a swift disconnection of low-priority loads after detection of a power network disturbance. It is designed to utilize the full potential of the IEC 61850 standard for communication and interoperability of substation automation devices. It is based on full integration of ABB's Relion protection and control relays, Remote I/O unit RIO600 and Human Machine Interface (HMI)-based on COM600 or equivalent.
The functionality can be also extended from covering MV feeders to LV feeders by inclusion of IEC 61850 compliant devices such as Emax2 circuit breakers equipped with Ekip Up protection and IEC 61850 communication modules.
The fast IEC 61850 GOOSE communication between the ABB devices ensures that the load-shedding signals are exchanged and distributed within milliseconds to ensure a superior performance without signal latencies.
- Load-shedding controller, PML630 based solution to be used for configurations with 8 power sources, 6 bus bars and 19 load priorities
- For bigger configurations, AC800M to be used as load-shedding controller, in combination with other Power Management functionality, working together with Relion relays and RIO600 device
- Following load-shedding modes are supported:
- Contingency based fast mode
- Overload or demand control based slow mode
- Frequency based
- Manual (priority and power definition) based
- A dedicated low-voltage load-shedding solution based on Emax2 (& Ekip Control+), motor controllers and MCBs is also possible.
- Load-shedding is required to prevent blackouts that can be very costly
- Post-islanding event or in already islanded network, if in-plant power generation is insufficient to meet power demand
- Maintains power balance by shedding low-priority loads to match loss of power source(s)
- Within tens of milliseconds to ensure frequency stability
- Ensuring power to critical loads in plant
- Carried out at lowest possible voltage level (granularity)=> at lowest MV outgoing feeder level or LV outgoing feeder level
- Offers increased flexibility and scalability and improved system integration and customization, fulfilling a variety of requirements
- All load-shedding modes enabled and available for use with every device
- Easy system integration using IEC 61850; guaranteed load-shedding command generation time of up to 20 milliseconds from disturbance detection