#
Optimization of a 660 MW_{e} Supercritical Power Plant Performance—A Case of Industry 4.0 in the Data-Driven Operational Management. Part 2. Power Generation

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## Abstract

**:**

_{e}supercritical coal combustion power plant. Based on the external validation test conducted by the unseen operation data, LSSVM has outperformed the MLR and ANN models to predict the power plant’s generator power. Later, the LSSVM model is used for the failure mode recovery and a very successful operation control excellence tool. Moreover, by adjusting the thermo-electric operating parameters, the generator power on an average is increased by 1.74%, 1.80%, and 1.0 at 50% generation capacity, 75% generation capacity, and 100% generation capacity of the power plant, respectively. The process modeling based on process data and data-driven process optimization strategy building for improved process control is an actual realization of industry 4.0 in the industrial applications.

## 1. Introduction

_{e}supercritical coal power plant. Considering 330 MW

_{e}and 660 MW

_{e}as 50% and 100% unit load (that is essentially the resistive power, and power factor between 0.85 to 1.00), the generator power (that accounts for both resistive and reactive power production from the power plant), is varied from 355 MVA to 715 MVA (50% generation capacity to nearly 100% generation capacity). The power plant’s characteristics operation data under the various power generation scenarios are taken from the Supervisory Information System (SIS). After machine learning techniques perform the data visualization test, i.e., self-organizing feature map (SOFM), MLR, ANN, and LSSVM, are employed to predict the generator’s power. The best performing and reliable process model is utilized for two principal objectives, i.e., (1) to plot the characteristics response of the generator power under the failure mode of the power plant; and (2) to optimize the generator power of the supercritical power plant for effective control of thermo-electric operating parameters.

## 2. Schematic of Power Plant

_{x}in the flue gases. After that, clean flue gas is discharged to the atmosphere via stack.

## 3. Training Data and Data Visualization

#### 3.1. Training Data for Process Modeling

#### 3.2. Self-Organizing Feature Map (SOFM)

## 4. The Theoretical Background of Modeling Techniques

#### 4.1. Multiple Linear Regression

_{1}, x

_{2}, …, x

_{i}are independent variables, then the basic MLR model will be given in the following equation,

_{0}, b

_{1}, b

_{2},…, b

_{i}are the regression coefficients, and “e” accounts for the error in fitting the regression line across the observed data [41].

#### 4.2. Artificial Neural Network

_{1}and W

_{2}are the weights at the input and hidden layer, b

_{1}and b

_{2}are the biases at different layers and f

_{1}and f

_{2}are the transfer functions in the hidden and output layer, respectively.

#### 4.3. Least Square Support Vector Machine

**w**is a weight vector, $\gamma $ is a penalty parameter, $\xi $ is the ith error variable, $\phi $ is a nonlinear function mapping inputs from the data to a higher feature space, and b is a bias.

## 5. Development of Process Models

#### 5.1. Errors and Evaluation Criteria

^{2}), root-mean-square error (RMSE), normalized RMSE (NRMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) of the models’ prediction are calculated to evaluate the robustness and effectiveness of the process models. The definition of the evaluation criteria is given below,

#### 5.2. Validation Case against Unseen Data

^{2}, RMSE, NRMSE, MAE and MAPE for MLR model are 0.99958, 2.674 MVA 0.834%, 1.940 MVA, and 0.007%, respectively.

^{2}, RMSE, NRMSE, MAE and MAPE for ANN [24-12-1] are 0.999707, 2.093 MVA, 0.653%, 1.447 MVA and 0.006% respectively.

^{2}, RMSE, NRMSE. MAE and MAPE for the LSSVM model are 0.999878, 1.521MVA. 0.474%, 1.069 MVA, and 0.004%, respectively. The comparative performance analysis of MLR, ANN [24-12-1], and LSSVM model performance against the evaluation criteria are presented in Figure 5 and Table 5.

## 6. Results and Discussion

#### 6.1. The Combined Effect of Excitation Voltage and Excitation Current on the Generator Power

_{e}), the excitation voltage and excitation current are systematically increased from the minimum to maximum values, whereas the remaining thermo-electric operating parameters are maintained at the average values as mentioned in Table 6. Keeping the remaining thermo-electric operating parameters at the average values is essential to sustain the 50% and 100% unit load from the generator.

#### 6.2. Generator Power Control during Coal Mill Trip Accident (Failure Mode Recovery and Mitigation of Cost of Failure)

#### 6.3. Effect of Adjustment in Thermo-Electric Operating Parameters for Optimal Generator Power (A Case of AI for Operation Control Excellence Tool)

## 7. Conclusions

_{e}supercritical coal power plant.

## Author Contributions

## Funding

## Acknowledgments

## Conflicts of Interest

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**Figure 5.**External validation data graphs of MLR, ANN [24-12-1] and LSSVM models. (

**a**) MLR (

**b**) ANN (

**c**) LSSVM.

**Figure 6.**Effect of the combined effect of excitation voltage and current on reactive generator power (

**a**) 50% unit load; (

**b**) 100% unit load.

**Figure 8.**Comparison of actual and optimal generator power (

**a**) at 50% generation capacity (

**b**) 75% generation capacity (

**c**) 100% generation capacity.

Sensor | Make | Model | |
---|---|---|---|

1 | Coal flow rate (M_{c}) | Vishay Precision Group (USA) | 3410 |

2 | Air flow rate (M_{a}) | Siemens (Germany) | 7MF4433-1BA22-2AB6-Z |

3 | Water/Coal ratio (w/c) | Soft sensor | Soft sensor |

4 | Middle temp. (T_{mid}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

5 | LT Eco water outlet temp. (T_{LT.ECO}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

6 | APH air outlet temp. (T_{a})_{APH} | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

7 | % O_{2} in flue gas at APH outlet (% O_{2}) | Walsn (Canada) | 0AM-800-R |

8 | Flue gas temp. after APH ((T_{fg})_{APH}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

9 | Ambient temp. (T_{amb}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

10 | Feed water pressure (FWP) | Siemens (Germany) | 7MF4033-1GA50-2AB6-Z |

11 | Feed water temp. (FWT) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

12 | Feed water flow (FWF) | Siemens (Germany) | 7MF4533-1FA32-2AB6-Z |

13 | Main steam pressure (MSP) | Siemens (Germany) | 7MF4033-1GA50-2AB6-Z |

14 | Main steam temp. (MST) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

15 | Reheat pressure (RHP) | Siemens (Germany) | 7MF4033-1GA50-2AB6-Z |

16 | Reheat temp. (RHT) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

17 | Absolute condenser vacuum (P_{vac}) | Siemens STTRANS D PS III | 7MF4233-1GA50-2AB6-Z |

18 | Deaerator temp. (T_{d}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

19 | Attemperation water flow rate(AWF) | Siemens (Germany) | 7MF4533-1FA32-2AB6-Z |

20 | Condensate temp. (T_{C}) | Anhui Tiankang China Thermocouple | WRNR2(K TYPE) |

21 | Auxiliary power (P_{aux}) | Nanjing Suatak Measurement and Control System | STM3-WT-3-155A4BN |

22 | Turbine speed (N) | Braun (Germany) | A5S |

23 | Excitation voltage (Exc. V) | Siemens (Germany) | SPPA-E3000 SES 530 |

24 | Excitation current (Exc. I) | Siemens (Germany) | SPPA-E3000 SES 530 |

25 | Generator power (G.P) | Nanjing Suatak Measurement and Control System | STM3-WT-3-555A4BY |

LHV MJ/kg | Properties of Coal/wt.% | ||||
---|---|---|---|---|---|

24.23 | Moisture | Volatile Mater | Ash | Sulfur | Fixed Carbon ^{by diff.} |

2.5 | 23.73 | 16.6 | 0.55 | 57.66 |

Parameters | Unit | Min | Max | St. Dev |
---|---|---|---|---|

Coal flow rate (M_{c}) | t/h | 129 | 252 | 86.76 |

Air flow rate (M_{a}) | t/h | 1469 | 2636 | 825 |

Water/Coal ratio (w/c) | - | 6.98 | 8.49 | 1.07 |

Middle temp. (T_{mid}) | °C | 343 | 425 | 57.78 |

LT Eco water outlet temp. (T_{LT.ECO}) | °C | 90 | 100 | 6.94 |

APH air outlet temp. (T_{a})_{APH} | °C | 311 | 352 | 29.43 |

% O_{2} in flue gas at APH outlet (% O_{2}) | % | 5.27 | 8.50 | 2.28 |

Flue gas temp. after APH (T_{fg})_{APH} | °C | 120 | 157 | 26.84 |

Ambient temp. (T_{amb}) | °C | 5.0 | 43.0 | 27.2 |

Feed water pressure (FWP) | MPa | 15.0 | 30.0 | 10.39 |

Feed water temp. (FWT) | °C | 260 | 299 | 27.67 |

Feed water flow (FWF) | t/h | 942 | 1987 | 738.98 |

Main steam pressure (MSP) | MPa | 13.0 | 24.4 | 8.05 |

Main steam temp. (MST) | °C | 550 | 569 | 13.97 |

Reheat pressure (RHP) | MPa | 2.6 | 5.0 | 1.69 |

Reheat temp. (RHT) | °C | 553 | 569 | 10.88 |

Absolute Condenser vacuum (P_{vac}) | kPa | 95.60 | 89.30 | 4.48 |

Deaerator temp. (T_{d}) | °C | 164 | 190 | 18.59 |

Attemperation water flow rate (AWF) | t/h | 4 | 97 | 65.94 |

Condensate temp. (T_{C}) | °C | 27 | 47 | 13.8 |

Auxiliary power (P_{aux}) | MW_{e} | 20.3 | 29.2 | 6.31 |

Turbine speed (N) | Rpm | 2986 | 3017 | 22.49 |

Excitation voltage (Exc. V) | V | 186 | 435 | 182.65 |

Excitation current (Exc. I) | A | 1940 | 4144 | 1629.85 |

Generator power (G.P) | MVA | 355.1 | 714.9 | 254.44 |

Hidden Layer Neurons | R^{2} | RMSE | NRMSE | MAE | MAPE |
---|---|---|---|---|---|

- | - | MVA | % | MVA | % |

10 | 0.999369 | 3.177 | 0.991 | 2.171 | 0.009 |

11 | 0.999685 | 2.344 | 0.731 | 1.597 | 0.006 |

12 | 0.999707 | 2.093 | 0.653 | 1.447 | 0.006 |

13 | 0.999218 | 3.391 | 1.057 | 2.173 | 0.009 |

14 | 0.999267 | 3.638 | 1.134 | 2.528 | 0.01 |

15 | 0.999612 | 2.609 | 0.813 | 1.903 | 0.007 |

16 | 0.999692 | 2.212 | 0.69 | 1.534 | 0.006 |

17 | 0.999468 | 3.095 | 0.965 | 2.177 | 0.008 |

18 | 0.999395 | 3.084 | 0.962 | 2.123 | 0.008 |

19 | 0.999536 | 2.401 | 0.749 | 1.672 | 0.007 |

20 | 0.999568 | 2.532 | 0.79 | 1.98 | 0.007 |

21 | 0.999684 | 2.218 | 0.692 | 1.627 | 0.006 |

22 | 0.999447 | 2.899 | 0.904 | 2.037 | 0.008 |

23 | 0.999491 | 2.742 | 0.855 | 2.055 | 0.008 |

24 | 0.999655 | 2.447 | 0.763 | 1.853 | 0.007 |

25 | 0.999244 | 3.281 | 1.023 | 2.228 | 0.009 |

26 | 0.999551 | 2.552 | 0.796 | 1.81 | 0.007 |

27 | 0.999656 | 2.608 | 0.813 | 1.931 | 0.007 |

28 | 0.999601 | 2.549 | 0.795 | 1.669 | 0.007 |

29 | 0.999337 | 3.595 | 1.121 | 2.677 | 0.01 |

30 | 0.999438 | 3.066 | 0.956 | 2.164 | 0.008 |

31 | 0.999698 | 2.328 | 0.726 | 1.831 | 0.006 |

32 | 0.999556 | 2.533 | 0.79 | 1.783 | 0.007 |

33 | 0.999495 | 2.931 | 0.914 | 2.132 | 0.008 |

34 | 0.99924 | 3.354 | 1.046 | 2.729 | 0.009 |

35 | 0.999483 | 2.817 | 0.878 | 2.065 | 0.008 |

36 | 0.999668 | 2.27 | 0.708 | 1.723 | 0.006 |

Models | R^{2} | RMSE | NRMSE | MAE | MAPE |
---|---|---|---|---|---|

- | MVA | % | MVA | % | |

MLR | 0.99958 | 2.674 | 0.834 | 1.940 | 0.007 |

ANN [24-12-1] | 0.999707 | 2.093 | 0.653 | 1.447 | 0.006 |

LSSVM | 0.999858 | 1.521 | 0.474 | 1.069 | 0.004 |

Operating Parameters | 50% Unit Load (MW _{e}) | 100% Unit Load (MW _{e}) | |||||
---|---|---|---|---|---|---|---|

Unit | Min | Avg | Max | Min | Avg | Max | |

Coal flow rate (M_{c}) | t/h | 129 | 137 | 156 | 210 | 238 | 252 |

Air flow rate (M_{a}) | t/h | 1469 | 1559 | 1703 | 2197 | 2472 | 2636 |

Water/Coal ratio (w/c) | - | 6.98 | 7.52 | 8.08 | 7.63 | 8.09 | 8.49 |

Middle temp. (T_{mid}) | °C | 343 | 356 | 377 | 410 | 417 | 425 |

LT Eco water outlet temp. (T_{LT.ECO}) | °C | 94 | 98 | 100 | 90 | 93 | 100 |

APH air outlet temp. (T_{a})_{APH} | °C | 311 | 318 | 334 | 332 | 343 | 352 |

% O_{2} in flue gas at APH outlet (% O_{2}) | % | 7.37 | 7.93 | 8.50 | 5.27 | 5.88 | 6.85 |

Flue gas temp. after APH (T_{fg})_{APH} | °C | 120 | 127 | 144 | 129 | 137 | 157 |

Ambient temp. (T_{amb}) | °C | 5.1 | 25.2 | 39.3 | 5.0 | 25.7 | 43.3 |

Feed water pressure (FWP) | MPa | 15.4 | 16.2 | 18.0 | 26.8 | 29.7 | 30.0 |

Feed water temp. (FWT) | °C | 260 | 263 | 268 | 291 | 298 | 299 |

Feed water flow (FWF) | t/h | 942 | 1032 | 1139 | 1676 | 1923 | 1987 |

Main steam pressure (MSP) | MPa | 13.0 | 13.7 | 15.3 | 22.1 | 24.1 | 24.4 |

Main steam temp. (MST) | °C | 550 | 567 | 569 | 552 | 567 | 569 |

Reheat pressure (RHP) | MPa | 2.6 | 2.8 | 3.5 | 3.4 | 4.8 | 5.0 |

Reheat temp. (RHT) | °C | 553 | 567 | 569 | 561 | 567 | 568 |

Absolute condenser vacuum (P_{vac}) | kPa | 95.60 | 94.10 | 91.90 | 95.50 | 93.60 | 89.40 |

Deaerator temp. (T_{d}) | °C | 164 | 166 | 170 | 181 | 187 | 190 |

Attemperation water flow rate (AWF) | t/h | 5 | 39 | 81 | 6 | 58 | 97 |

Condensate temp. (T_{C}) | °C | 27 | 33 | 40 | 31 | 35 | 47 |

Auxiliary power (P_{aux}) | MW_{e} | 20.3 | 22.2 | 24.0 | 25.4 | 27.8 | 29.2 |

Turbine speed (N) | Rpm | 2986 | 3003 | 3017 | 2986 | 3002 | 3017 |

Excitation voltage (Exc. V) | V | 186 | 218 | 277 | 297 | 359 | 431 |

Excitation current (Exc. I) | A | 1940 | 2259 | 2845 | 3022 | 3556 | 4124 |

**Table 7.**Summary of actual and adjusted thermo-electric operating parameters at 50% generation capacity.

Thermo-Electric Operating Parameters | Unit | 50% Generation Capacity (MVA) | |||||
---|---|---|---|---|---|---|---|

Actual | Adjusted | Actual | Adjusted | Actual | Adjusted | ||

Coal flow rate (M_{c}) | t/h | 134 | 134 | 135 | 138 | 137 | 137 |

Air flow rate (M_{a}) | t/h | 1519 | 1500 | 1508 | 1497 | 1531 | 1519 |

Water/Coal ratio (w/c) | - | 7.46 | 7.43 | 8.05 | 7.8 | 7.69 | 7.43 |

Middle temp. (T_{mid}) | °C | 354 | 357 | 366 | 368 | 353 | 356 |

LT Eco water outlet temp. (T_{LT.ECO}) | °C | 98 | 99 | 98 | 99 | 96 | 97 |

APH air outlet temp. (T_{a})_{APH} | °C | 315 | 318 | 334 | 336 | 323 | 325 |

% O_{2} in flue gas at APH outlet (% O_{2}) | % | 7.98 | 7.90 | 7.60 | 7.55 | 7.63 | 7.59 |

Flue gas temp. after APH (T_{fg})_{APH} | °C | 127 | 121 | 133 | 127 | 129 | 121 |

Ambient temp. (T_{amb}) | °C | 15.0 | 15.0 | 12.0 | 12.0 | 27.0 | 27.0 |

Feed water pressure (FWP) | MPa | 15.9 | 15.9 | 17.3 | 17.3 | 16.4 | 16.4 |

Feed water temp. (FWT) | °C | 263 | 265 | 267 | 269 | 263 | 265 |

Feed water flow (FWF) | t/h | 1004 | 996 | 1088 | 1076 | 1056 | 1043 |

Main steam pressure (MSP) | MPa | 13.5 | 13.5 | 14.8 | 14.8 | 13.6 | 13.6 |

Main steam temp. (MST) | °C | 550 | 566 | 551 | 566 | 551 | 566 |

Reheat pressure (RHP) | MPa | 2.7 | 2.7 | 3.3 | 3.3 | 2.7 | 2.7 |

Reheat temp. (RHT) | °C | 559 | 567 | 560 | 567 | 561 | 567 |

Absolute condenser vacuum (P_{vac}) | kPa | 93.84 | 93.92 | 94.35 | 94.4 | 93.55 | 93.62 |

Deaerator temp. (T_{d}) | °C | 165 | 167 | 168 | 169 | 167 | 169 |

Attemperation water flow rate (AWF) | t/h | 56 | 35 | 27 | 19 | 14 | 9 |

Condensate temp. (T_{C}) | °C | 34 | 34 | 32 | 32 | 36 | 36 |

Auxiliary power (P_{aux}) | MW_{e} | 20.5 | 20.3 | 22.4 | 22.2 | 20.8 | 20.5 |

Turbine speed (N) | Rpm | 3002 | 3002 | 3009 | 3009 | 3006 | 3006 |

Excitation voltage (Exc. V) | V | 223 | 223 | 210 | 210 | 272 | 272 |

Excitation current (Exc. I) | A | 2323 | 2323 | 2188 | 2188 | 2776 | 2776 |

**Table 8.**Summary of actual and adjusted thermo-electric operating parameters at 75% generation capacity.

Thermo-Electric Operating Parameters | Unit | 75% Generation Capacity (MVA) | |||||
---|---|---|---|---|---|---|---|

Actual | Adjusted | Actual | Adjusted | Actual | Adjusted | ||

Coal flow rate (M_{c}) | t/h | 184 | 184 | 201 | 201 | 193 | 193 |

Air flow rate (M_{a}) | t/h | 1983 | 1965 | 2142 | 2129 | 2064 | 2034 |

Water/Coal ratio (w/c) | - | 7.73 | 7.61 | 8.04 | 7.95 | 7.7 | 7.58 |

Middle temp. (T_{mid}) | °C | 383 | 385 | 401 | 405 | 378 | 382 |

LT Eco water outlet temp. (T_{LT.ECO}) | °C | 97 | 98 | 92 | 93 | 95 | 96 |

APH air outlet temp. (T_{a})_{APH} | °C | 322 | 325 | 333 | 338 | 325 | 328 |

% O_{2} in flue gas at APH outlet (% O_{2}) | % | 6.76 | 6.70 | 6.25 | 6.21 | 6.67 | 6.53 |

Flue gas temp. after APH (T_{fg})_{APH} | °C | 127 | 122 | 131 | 126 | 137 | 131 |

Ambient temp. (T_{amb}) | °C | 8.0 | 8.0 | 10.0 | 10.0 | 27.0 | 27.0 |

Feed water pressure (FWP) | MPa | 21.7 | 21.7 | 24.8 | 24.8 | 22.2 | 22.2 |

Feed water temp. (FWT) | °C | 278 | 280 | 287 | 289 | 279 | 281 |

Feed water flow (FWF) | t/h | 1424 | 1400 | 1613 | 1598 | 1487 | 1463 |

Main steam pressure (MSP) | MPa | 17.7 | 17.7 | 20.4 | 20.4 | 18.2 | 18.2 |

Main steam temp. (MST) | °C | 554 | 567 | 554 | 566 | 554 | 568 |

Reheat pressure (RHP) | MPa | 3.4 | 3.4 | 4.06 | 4.06 | 3.7 | 3.7 |

Reheat temp. (RHT) | °C | 560 | 567 | 560 | 567 | 563 | 567 |

Absolute condenser vacuum (P_{vac}) | kPa | 95.24 | 95.32 | 94.51 | 94.6 | 92.74 | 92.82 |

Deaerator temp. (T_{d}) | °C | 174 | 175 | 180 | 181 | 174 | 176 |

Attemperation water flow rate (AWF) | t/h | 33 | 12 | 39 | 25 | 19 | 12 |

Condensate temp. (T_{C}) | °C | 30 | 30 | 32 | 32 | 38 | 38 |

Auxiliary power (P_{aux}) | MW_{e} | 25.1 | 24.9 | 25.7 | 25.4 | 25 | 24.7 |

Turbine speed (N) | Rpm | 3001 | 3001 | 3001 | 3001 | 3003 | 3003 |

Excitation voltage (Exc. V) | V | 269 | 269 | 285 | 285 | 296 | 296 |

Excitation current (Exc. I) | A | 2757 | 2757 | 2904 | 2904 | 3012 | 3012 |

**Table 9.**Summary of actual and adjusted thermo-electric operating parameters at 100% generation capacity.

Thermo-Electric Operating Parameters | Unit | 100% Generation Capacity (MVA) | |||||
---|---|---|---|---|---|---|---|

Actual | Adjusted | Actual | Adjusted | Actual | Adjusted | ||

Coal flow rate (M_{c}) | t/h | 243 | 243 | 239 | 239 | 248 | 248 |

Air flow rate (M_{a}) | t/h | 2453 | 2418 | 2399 | 2399 | 2507 | 2470 |

Water/Coal ratio (w/c) | - | 7.98 | 7.96 | 8.15 | 8.12 | 7.85 | 7.79 |

Middle temperature (T_{mid}) | °C | 415 | 417 | 413 | 415 | 417 | 419 |

LT Eco water outlet temperature (T_{LT.ECO}) | °C | 92 | 93 | 91 | 92 | 95 | 96 |

APH air outlet temperature (T_{a})_{APH} | °C | 340 | 346 | 336 | 343 | 338 | 346 |

% O_{2} in flue gas at APH outlet (% O_{2}) | % | 5.79 | 5.63 | 5.64 | 5.64 | 5.43 | 5.21 |

Flue gas temperature after APH (T_{fg})_{APH} | °C | 133 | 130 | 134 | 129 | 148 | 135 |

Ambient temperature (T_{amb}) | °C | 5.0 | 5.0 | 10.0 | 10.0 | 34.0 | 34.0 |

Feed water pressure (FWP) | MPa | 29.7 | 29.7 | 29.6 | 29.6 | 29.5 | 29.5 |

Feed water temperature (FWT) | °C | 297 | 299 | 297 | 299 | 297 | 300 |

Feed water flow (FWF) | t/h | 1950 | 1935 | 1951 | 1936 | 1947 | 1935 |

Main steam pressure (MSP) | MPa | 24.1 | 24.1 | 24 | 24 | 23.8 | 23.8 |

Main steam temperature (MST) | °C | 553 | 567 | 552 | 566 | 553 | 568 |

Reheat pressure (RHP) | MPa | 4.8 | 4.8 | 4.8 | 4.8 | 4.2 | 4.2 |

Reheat temperature (RHT) | °C | 564 | 566 | 565 | 569 | 563 | 568 |

Absolute condenser vacuum (P_{vac}) | kPa | 94.87 | 94.93 | 94.38 | 94.44 | 90.11 | 90.26 |

Deaerator temperature (T_{d}) | °C | 186 | 189 | 187 | 188 | 189 | 191 |

Attemperation water flow rate (AWF) | t/h | 50 | 20 | 47 | 18 | 58 | 19 |

Condensate temperature (T_{C}) | °C | 31 | 31 | 33 | 33 | 46 | 46 |

Auxiliary power (P_{aux}) | MW_{e} | 27.4 | 27.1 | 28.0 | 27.9 | 27.8 | 27.5 |

Turbine speed (N) | Rpm | 2996 | 2996 | 3012 | 3012 | 3004 | 3004 |

Excitation voltage (Exc. V) | V | 364 | 364 | 310 | 310 | 396 | 396 |

Excitation current (Exc. I) | A | 3598 | 3598 | 3131 | 3131 | 3865 | 3865 |

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## Share and Cite

**MDPI and ACS Style**

Muhammad Ashraf, W.; Moeen Uddin, G.; Hassan Kamal, A.; Haider Khan, M.; Khan, A.A.; Afroze Ahmad, H.; Ahmed, F.; Hafeez, N.; Muhammad Zawar Sami, R.; Muhammad Arafat, S.;
et al. Optimization of a 660 MW_{e} Supercritical Power Plant Performance—A Case of Industry 4.0 in the Data-Driven Operational Management. Part 2. Power Generation. *Energies* **2020**, *13*, 5619.
https://doi.org/10.3390/en13215619

**AMA Style**

Muhammad Ashraf W, Moeen Uddin G, Hassan Kamal A, Haider Khan M, Khan AA, Afroze Ahmad H, Ahmed F, Hafeez N, Muhammad Zawar Sami R, Muhammad Arafat S,
et al. Optimization of a 660 MW_{e} Supercritical Power Plant Performance—A Case of Industry 4.0 in the Data-Driven Operational Management. Part 2. Power Generation. *Energies*. 2020; 13(21):5619.
https://doi.org/10.3390/en13215619

**Chicago/Turabian Style**

Muhammad Ashraf, Waqar, Ghulam Moeen Uddin, Ahmad Hassan Kamal, Muhammad Haider Khan, Awais Ahmad Khan, Hassan Afroze Ahmad, Fahad Ahmed, Noman Hafeez, Rana Muhammad Zawar Sami, Syed Muhammad Arafat,
and et al. 2020. "Optimization of a 660 MW_{e} Supercritical Power Plant Performance—A Case of Industry 4.0 in the Data-Driven Operational Management. Part 2. Power Generation" *Energies* 13, no. 21: 5619.
https://doi.org/10.3390/en13215619