Seminar Details
2009-03-24 (14.00) : LMI formulation for Optimal Control of coal fired Power Plants
At Euler building
Organized by Mathematical Engineering
Speaker :
Emile SIMON (CESAME)
Abstract :
Thermal power plants are usually controlled by classical regulations
(mostly PIDs), developed with a decentralised model, splitting the system
in many different SISO loops. However, multiple providers and distributed
generation are more likely to cause sudden and large changes of the load
demand. Improving the performance is thus a commercial commodity of great
importance in the current markets state of privatised power industry.
Therefore, we consider the solution of an optimal multivariable control.
The objective pursued here was already studied in a previous work
["Performance Limitations arising in the Control of Power Plants"
presented the 16/12/08 by Vincent Wertz], a key feature was the relation
between the value of the tracking cost and the delay structure of the
plant.
Here a new method is chosen, the problem is cast into an LMI formulation.
At first we develop the same trade-off results as previously found. But
now the new formulation allows one to add constraints with other LMI's.
Since in this paper the control energy is taken into account, a new LMI
reducing the control input is developed.
Without constraint, the coal flow input was too large. So a new LMI is
introduced, allowing to reduce the norm of the optimal controller and thus
the size of the input produced. This is shown to have a limited effect on
the original objective, meaning a slight impact on the performance.
We conclude from the results that the control is significantly improved,
while having control inputs within their limits.