Profit Optimizer

Profit Optimizer

Salient features of this correction are:

1. The new correction works independently of RGMO. RGMO correction is implemented as per grid code and no changes are done to this. It will be visible more during FAST frequency changes. It is possible that frequency very slowly drifts away from 50.00 Hz but RGMO correction is not at all giving significant correction. During such times profit optimisation correction will help in earning UI.

2. Profit correction overall limits are settable between 10 to 25 MW. Correction droop is settable between 4 to 10% (default 4%). Breakeven frequency is settable (presently 50.00 Hz). Correction will be be subject to all directional blocks/limits as applicable normally in CMC.

3. Profit correction is based on selected frequency, which may be instanteneous, block average or weighted average - selection will be decided dynamically based on breakeven and asking frequencies, as well as block elapsed time. Note: asking frequency is the calculated frequency value which is required to be exactly maintained for blokc remaining time to bring block average to exactly breakeven. weighted average frequency is calculated taking block average frequency for block elapsed time and assuming instantaneous frequency for block remaining time.

4. To determine selection strategy, one block is divided into 5 segments of 3 minutes each.

i) First segment will always be giving correction as per instantaneous frequency.

ii) Second segment will give correction as per inst.freq. if inst.freq. and avg.freq. are on the same side of breakeven, and inst.freq. is more drifted. Inst.freq. can also be selected if it goes to other side of breakeven as compared to avg.freq.

Avg.freq. will be selected if inst.freq. and avg.freq. are on the same side of breakeven, and inst.freq. is between avg.freq. and breakeven.

iii)Third and fourth segments will also give correction as per inst.freq. if inst.freq. and avg.freq. are on the same side of breakeven, and inst.freq. is more drifted. Inst.freq. can also be selected if it goes to other side of breakeven as compared to avg.freq, and beyond asking freq. Avg.freq. will be selected if inst.freq. and avg.freq. are on the same side of breakeven, and inst.freq. is between avg.freq. and breakeven. Weighted avg.freq. will be selected if inst.freq. goes to other side of breakeven as compared to avg.freq, but within asking freq.

v) Fifth segment will behave similar to third and fourth till preset timer (60-120 sec), and then follow instantaneous frequency in order to be ready for next block start.

Correction is under implementation in Stage-II and III, and will be communicated in respective register accordingly. Performance in service may be kept under observation and feedback may be given to C&I.

It is once again brought to notice that the correction will have its desired effect of load change only if ALL mills are in auto, otherwise it will just result in throttle pressure larger variations (and then pressure correction will nullify it leading to little effective load change). Hence it is required that ALL mills be kept in auto for maximum possible duration (except for short periods during mill changeovers) to get maximum benefit out of this scheme.