Optimizing the Allocation of the Relay Setting Related to Power Grid and over Frequency Generator Tripping Scheme

Through the summary of typical accident, the problem between the over speed protection device of thermal power unit steam turbine and over frequency generator tripping measure is analyzed in island operation of sending ends of regional grid. The optimizing allocation principle between over frequency generator tripping measure and over speed protection equipment is put forward. By a variety of program analysis and comparison, the optimizing scheme is given. Finally, the typical models of thermal power unit steam turbine over speed protection are established in software. Based on a practical power system as an example, the whole process of islanding is simulated. Checking the coordination with existing over frequency generator tripping measure and the relay setting related to power network in the islanding operation, the validity and practicability of the optimal scheme and principle are analyzed. With the method, the regional grid will remain safe and stable.

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Analysis of Influence of FCB Test on 1000MW Steam Turbine Safety

Volume 14: Emerging Technologies; Engineering Management, Safety, Ethics, Society, and Education; Materials: Genetics to Structures ◽

10.1115/imece2014-36988 ◽

2014 ◽

Author(s):

Dan-mei Xie ◽

Yi Yang ◽

Chang Chen ◽

Peng-fei Hu ◽

Jie Guo ◽

...

Keyword(s):

Power System ◽

Water Level ◽

Steam Turbine ◽

Test Data ◽

Power Grid ◽

Thermal Power ◽

Maximum Speed ◽

Steam Temperature ◽

Dc System ◽

Thermal Equipment

The capacity of power grid in China increases rapidly. Because of the reliability of multi-infeed DC system in the grid, power system damping is relatively weak. Realizing isolated island operation of thermal power units with FCB (fast cut back) ability is considered to be the best solution of quick restoration of power grid. Taking a 1000MW USC (Ultra-supercritical) unit as an example, based on the data of the unit’s load refection tests, this paper conducts a look at several aspects of research: (1) predicting the maximum speed rise of rotor during FCB process with different loads by using Simulink; (2) predicting the water level of deaerator and condenser during FCB process with different loads by same method; (3) predicting the highest exhausted steam temperature of HP cylinder during FCB process with different loads by using FEM; (4) comparing these key parameters with FCB test data, it shows that the predicted results agree with test data very well. (5) analyzing the influence of FCB test on the safety and life loss of the thermal equipment.

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Multi-Time Scale Rolling Economic Dispatch for Wind/Storage Power System Based on Forecast Error Feature Extraction

Energies ◽

10.3390/en11082124 ◽

2018 ◽

Vol 11 (8) ◽

pp. 2124 ◽

Cited By ~ 6

Author(s):

Li Han ◽

Rongchang Zhang ◽

Xuesong Wang ◽

Yu Dong

Keyword(s):

Power System ◽

Real Time ◽

Wind Power ◽

Power Unit ◽

Time Scale ◽

Forecast Error ◽

Thermal Power ◽

Time Error ◽

The Real ◽

The Impact

This paper looks at the ability to cope with the uncertainty of wind power and reduce the impact of wind power forecast error (WPFE) on the operation and dispatch of power system. Therefore, several factors which are related to WPFE will be studied. By statistical analysis of the historical data, an indicator of real-time error based on these factors is obtained to estimate WPFE. Based on the real-time estimation of WPFE, a multi-time scale rolling dispatch model for wind/storage power system is established. In the real-time error compensation section of this model, the previous dispatch plan of thermal power unit is revised according to the estimation of WPFE. As the regulating capacity of thermal power unit within a short time period is limited, the estimation of WPFE is further compensated by using battery energy storage system. This can not only decrease the risk caused by the wind power uncertainty and lessen wind spillage, but also reduce the total cost. Thereby providing a new method to describe and model wind power uncertainty, and providing economic, safe and energy-saving dispatch plan for power system. The analysis in case study verifies the effectiveness of the proposed model.

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Study on Peaking Ability and Operation Safety of Thermal Power Unit in Peak Load Regulation of Power System

2018 2nd IEEE Conference on Energy Internet and Energy System Integration (EI2) ◽

10.1109/ei2.2018.8581889 ◽

2018 ◽

Cited By ~ 1

Author(s):

Xuhui Zhang ◽

Xingsen Yang ◽

Haichao Wang ◽

Ke Liu ◽

Fuxing Cui ◽

...

Keyword(s):

Power System ◽

Power Unit ◽

Thermal Power ◽

Peak Load ◽

Load Regulation

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Optimal Scheduling of Power System Incorporating the Flexibility of Thermal Units

Energies ◽

10.3390/en11092195 ◽

2018 ◽

Vol 11 (9) ◽

pp. 2195 ◽

Cited By ~ 1

Author(s):

Tong Guo ◽

Yajing Gao ◽

Xiaojie Zhou ◽

Yonggang Li ◽

Jiaomin Liu

Keyword(s):

Power Systems ◽

Power System ◽

Wind Power ◽

Power Unit ◽

Large Scale ◽

Thermal Power ◽

Entropy Method ◽

Optimal Scheduling ◽

Evaluation Index System ◽

Total Power

Due to the randomness, volatility and intermittent nature of wind power, power systems with significant wind penetration face serious “curtailment” problems. The flexibility of a power system is an important factor that affects the large-scale consumption of wind power. Based on this fact, this paper takes into account the economics and flexibility of the system, and proposes an optimal scheduling method that takes the flexibility of each thermal power unit into account. Firstly, a comprehensive evaluation index system of thermal power unit flexibility is designed by an analytic hierarchy process and entropy method. The system covers the technical indexes and economic characteristics of thermal power units and is able to quantitatively evaluate the different types of thermal power units in the system. Secondly, a multi-objective optimization scheduling model involving the overall flexibility of the unit and the total power generation cost is established. Finally, the correctness and effectiveness of the proposed indicators and models are verified by a case study.

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