Power System Reliability

Power, Steam & Gas System Dynamic Study

Client

Tata Steel Kalinganagar

Location

Kalinganagar Industrial Complex, Odisha, India

Project Overview

Tata Steel Kalinganagar (TSK) has set an integrated steel plant with an ultimate capacity of 6MTPA, with captive generation at Kalinga Nagar Industrial Complex in Odisha. The project is carried out in two phases, and phase 1 was completed around 2015. The estimated load demand of the steel plant after phase 1 is about 244 MW.

Plant Configuration

The power sources to the steel plant in Phase-1 are 2X67.5 MW gas based captive power plant (CPP1), 1X22 MW Top gas recovery turbine (TRT) and 1X12MW coke dry quenching (CDQ), 5X8MW DG sets and grid.

TSK Power system is tightly coupled & highly interdependent with respect to Gas, Steam & Power system. A single weak link can trigger a complete system breakdown.

Purpose

Frequent tripping's leading to complete blackouts, due to cascade effect, mostly during transition to island operation, resulting in major downtime. Solvina was asked to illustrate various dynamic issues & design gaps in the power system that may cause plant outages, and to verify suggested remedies to improve the overall plant reliability and stability.

Scope of Work

The study considered the following aspects:

Power System Studies: Disturbance and Island operations study; Transient stability studies; Short-circuit studies; Conclusion and Recommendations
Steam and Gas network: Basic Control strategy; Design Gaps and Recommendations; Suggestions for efficient operations of CDQ-turbine

Method and Results

The holistic approach was applied with a focus on electrical study and power generation response.

The recommendations for power system reliability are as follows:

Create redundancy and margin in the integrated plant.
Improve the boiler and steam net control to improve the stability of CPP.
Implement new criteria for active grid islanding when grid properties are outside boundaries.
Focus on running the complete large island only.
Run both CPP turbines in frequency control.
Start and synchronize DGs in island operation.
Allow restart of electric load in island mode that has tripped.
Consider not to initiate shutdown of BF when islanding occurs.

Conclusion

Recommendations were found very thoughtful & deep diving. Improved the performance of existing system w.r.t both reliability & availability.