Information and Regimes Diagnostics System "MENTOR"

1. Introduction:

   The assuring of safety and reliability of turbine units at Power Stations remains to be the leading target of power Industry, alongside with the problems of efficiency, availability and operational life extension.
   One of the leading factors here is maintaining of optimal conditions for turbine operation on transient regimes. For such regimes the manufacturer's instructions are existing but they are rather rigid and one-sided, not accounting for different initial thermal state, so that eventual deviation of at least one parameter makes proper use of the starting up instructions almost impossible. The drawing of right decision here is a matter of operator qualification and not always optimal.

2. Purpose:

   The IDS "Mentor" is designed as a real-time help for turbine operator both for starting regimes (including performing, running up, loading and for starting as well as transient regimes, from any initial thermal state.
The way of delivering the help is to display on computer's monitor the optimal graphs for prognosed and recommended changing of main steam parameters together with special criteria determining the reliability of the turbine.
   The prognosis is done taking into consideration the actual initial thermal state of aggregate providing acceptable stresses level, optimal thermal damage and fulfillment of all reliability requirements.
   The IDS "Mentor" provides the automatical control of operational parameters comparing them to acceptable values and as well as to reliability criteria. In cases of eventual deviations exceeding the normed values the IDS warns the operational personnel and gives instructions for corresponding correction of the parameters indicating the concrete measures to be taken.

3. IDS "Mentor" 's Software:

   The algorithm of the software is worked out on the basis of theoretical and physical experimental researches. It is also based on rich experience of LMZ and CKTI turbine specialists.
   The complete set of "Mentor" software includes the following:

1. The determination of the diagrams for the changings of steam parameters, speed of rotation and load from any initial thermal state providing optimal saving of turbine operational life.
2. The same for the unloading of the turbine.
3. The unloading and shutting down of the turbine with accelerated cooling down.
4. Correction of starting-up diagrams in case of eventual deviations of parameters from prognosed values.
5. Diagnostical assessment of steam parameters, load, speed of rotation, relative expansions of rotors, etc:
5.1 The qualitative estimation of turbine thermal expansions state detecting probability of axial rubbing along the steam path;
5.2 The estimation of probability of radial rubbing in HP and MP steam path;
5.3 Determinations of the causes for vacuum drop in the condenser;
5.4 The same for abnormal functioning of labyrinth end seals;
5.5 Estimation of the danger of water penetration in the turbine;
5.6 Assessment of the thermal state of horizontal flanges of HP and MP cylinders.
6. Calculation of the thermal state in critical sections of the turbine, diagnosis of damage, determination of operational life lost for every start-up.
7. Prognosis for relative thermal expansions values for HP and MP rotors on transient regimes.
8. Displaying of actual and prognoses parameters in the form of diagrams, tables and schemes.
9. Archiving of the data received for all operational period with availability of subsequent reviewing and analysis.
10. Information files for turbine operators.

4. Potentialities of the IDS "Mentor"

   Introduction of the "Mentor" system presents the following opportunities:

• to make prognosis and to display all diagrams for steam parameters (flow, rate, pressure, temperature) on all transient regimes for carrying out of starting-up and loading of the turbine in the optimal way. The parameters are calculated accounting for temperatures of stop-valves, HP governing stage (MP 1st stage), pipe-line temperatures, etc:
• to make prognosis and to display the diagrams for the boil parameters;
• to make prognosis for rotors relative thermal damage. All necessary aspects are taken always in consideration: public network requirements for starting-up and loading, reliability, permissible values of worming up for boiler headers, pipe-lines, valve boxes, turbine cylinders and rotors;
• the important feature of the system is the providing of recommended parameters in their mutual dependencies (of load and steam parameters) with the aim to avoid the water condensation befor or inside the turbine;
• to prevent the development of accidental situations, timely warning the operator in case of undesirable deviations of regime parameters;
• to provide real-time data on thermally stressed state of rotors in the process of starting-up, giving recommendations to operator in case of undesirable deviations of parameters;
• to extend the operation life of the rotors;
• to reduce starting-up period of the power generating unit;
• to save fuel while starting and loading;
• to estimate the state of the turbine on the basis of archive data;
• to print out all necessary protocols, diagrams, graphs, measurements;

5. Composition of IDS Mentor hardware.

5.1. Initial measurements.
For pick-ups (sensors) to estimate regime parameters and thermal state are mostly used those witch are already installed on turbine for standard measurements: pressure, temperature, expansion values, etc. The scope and number of measurements is a matter of agreement with the customer. The recommended minimum score of measurements is given is table 1.
5.2. Collection and acquisition of measured values.
5.3. Personal computer.

Initial measurement way be taken from the Control Room instruments on from existing (if any) information system or computer network.

Structure plan of IDS "Mentor"

Table 1

PARAMETER	PARAMETER
Life steam tem-re	MPC flange tem-re, external, right
Reheat steam tem-re	MPC flange tem-re, external, left
Life steam pressure	MPC flange tem-re, internal, right
Reheat steam tem-re	MPC flange tem-re, internal, left
Electrical (Heat) Load	Relative HP rotor expansion
Speed of rotation	Relative MP rotor expansion
HPC metal tem-re, top	Relative MP rotor expansion
HPC metal tem-re, bottom	Relative MP rotor expansion
MPC metal tem-re, top	Axial displacement
MPC metal tem-re, bottom	Rotor eccentricity
HP Stop value box tem-re	HP governing stage tem-re
MP Stop value box tem-re	HP governing stage pressure
HPC flange tem-re, external, right	1st MP stage tem-re
HPC flange tem-re, external, left	1st MP stage pressure
HPC flange tem-re, internal, right	Steam flow rate
HPC flange tem-re, internal, left	Steam flow rate

Note: HPC-high pressure cylinder, MPC-medium pressure cylinder

6. Guaranties obligations:

   The supplier guarantees the proper functioning of the system correcting on its own account all possible miss functions during one year of operation. Also the supplier may conclude a contract for after-sell servicing and up-dating.