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This paper provides an overview of probabilistic planning reserve margin studies at the California Independent System Operator. Currently, load serving entities in the State of California, with its retail load under the jurisdiction of the California Public Utility Commission, are required to procure reserve level at 15 - 17 percent. However, the requirement is deterministic in nature. The California...
In this paper, a new approach for the reliability modeling of large system which has multistate components is presented. The Monte Carlo simulation approach is introduced in this paper can facilitate a Markov process, and also provides frequency and duration of each state of the process. Large system with several components which have Markovian process can be analyzed using the proposed methodology...
This paper presents a flexible object-oriented computational model for composite systems reliability evaluation based on Sequential and Non-Sequential Monte Carlo Simulation. The main focus of the model is in the representation of time varying components, such as the wind generation and the load. The modeling flexibility enables the representation of complex network components and the comparison of...
This paper introduces “Copulas” analytical tool for multivariate modeling of stochastic harmonic generation mechanism. Additional stochastic harmonics can be modulated through the power inverters at the point of common coupling (PCC) under unbalanced non-linear loads. The proposed multivariate unbalance modeling via copulas is applied to evaluate aggregate harmonics injection at the PCC. Copulas have...
This paper presents a new comprehensive solution for maintenance scheduling of generating units in deregulated environments by applying an independent market, based on Genetic Algorithm (GA) and Monte-Carlo Simulation (MCS). In a deregulated environment each Generation Company (GENCO) desires to optimize the payoffs while independent system operator (ISO) has its reliability solicitudes. Mostly, these...
A revised generator random outage model is investigated in this paper which is used in risk-based monthly generator maintenance scheduling. First, the reason why the time-varying unit outage model should be used in monthly maintenance scheduling is presented. Second, the delayed renewal process was proposed to formulate the outage model for unscheduled units. This model can accommodate the impact...
The large growth in the wind power industry in the past years mainly focuses on a growing market and the development of large turbines and offshore farms. The high technical availability of wind turbines comes with a high need for frequent maintenance. Current maintenance planning is generally not optimized, and it is possible to make maintenance more efficient. Condition Monitoring Systems (CMS)...
The traditional reliability evaluation assesses the long-term performance of power system but its constant failure rate cannot reflect the time-varying performances in an operational time frame. This paper studies the operational reliability of power system in the real-time operating conditions based on online operation information obtained from the Energy Management System (EMS). A framework of operational...
In the literature many methods for overload relieving have been reported for determining a secure operating point. Most of these methods use conventional optimization techniques, which are generally time - consuming from a computation point of view, especially for large systems. Further the conventional optimization technique updates all the controllers for most of the operating conditions. Under...
The following topics are dealt with: smart grid; microgrids; renewable energy sources; power market; price forecasting; risk analysis; stochastic load; power system operation reliability analysis; power system control; power system protection; reliability centered maintenance; stochastic simulation; Monte Carlo techniques; probabilistic methods; power system planning; energy system planning; power...
Due to growing number of wind turbines (WT) within a wind farm (WF) scheduling of maintenance of turbines within the WF becomes challenging issue. Also, in instances when wind energy curtailments are required it can be difficult to decide which turbines should be shut down first. In this paper, a probabilistic methodology is presented to identify WT in the WF that face higher and lower wind speeds...
The paper proposed to use artificial neural networks (ANNs) to forecast electricity demand and to build the climate sensitive model. Digital simulation studies were conducted on the New Zealand electricity demand with temperature variations. The simulation study results have shown that the changes in temperature have a big impact on the expected total demand of electricity. As a result, it can be...
This paper presents the Automatic Generation Control (AGC) of an interconnected two-area multiple-units hydrothermal system in a competitive electricity market. In the present competitive electricity market, various kinds of apparatus with large capacity and fast power consumption may cause a serious problem of frequency oscillation. The oscillation of system frequency may sustain and grow to cause...
This paper studies linear systems under sustained random perturbations with the purpose of defining a stochastic stability reserve, i.e., of computing for a given size of the perturbation the values of the system parameters for which the system shows the best stability behavior. The stochastic perturbation model is given by a bounded Markov diffusion process. The Lyapunov exponent is used for computing...
Animals, such as squirrels, cause significant outages in overhead distribution systems. Models that would accurately estimate outages caused by animals would be very useful for utilities for year-end analysis of reliability performance of the distribution system. Large increase in outages caused by animals would require the utility to do further evaluation and take remedial actions. A two-layer Bayesian...
Wind is an important energy source and is regarded as a valuable alternative to more traditional electric power generating sources. Generating capacity from wind power behaves quite differently than that from more conventional sources as the wind is variable, intermittent and both terrain and site specific. The capacity credit that can be assigned to a particular wind power site is therefore highly...
Controllable electricity loads and storage devices have the potential to significantly and inexpensively increase the operating reliability of power systems, especially in systems with variable, unpredictable generation from renewable sources. However, in cases where a large number of small devices is used for operating reserves, it may be difficult to estimate the available reserve capacity, especially...
Original concept of tradeoff between risk and return in asset management is more challenging in electric distribution application. Complexities of distribution network challenge asset managers within decision makings. All asset management activities should be carried out in accordance with the whole distribution network. In other words, considering assets of distribution individually would be misleading...
This paper presents the results of probabilistic resource adequacy assessment of a large North American interconnected planning reserve sharing group-the Mid-Continent Area Power Pool (MAPP) for the 10-year planning horizon from 2009 - 2018. The objective of this study is to assess the collective resources of the MAPP participants to determine the minimum level of reserve requirements based upon reliability...
Many wavelet functions produce countless groups of wavelet bases. Every wavelet base has its time-frequency characteristics. There will bring about different results while analyzing the same problem with different wavelet bases. So selection of wavelet base will have influence on quality of fault diagnosis of motor. By analyzing and compare wavelet bases, author has selected the wavelet base which...
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