Assessing the reliability of the distribution network connected to wind dispersed production by investigating the effect of weather

Dissertation

Master's degree

Field: Power Electrical Engineering

Abstract

Due to the extent and complexity of distribution networks, the probability of an accident occurring in them is very high, and the occurrence of an accident can affect many subscribers. Therefore, reliability is one of the key parameters determining the success rate of the system in providing electricity to consumers. Therefore, the investigation and analysis of the reliability of the distribution network is of particular importance.

This work aims to evaluate the reliability of the distribution network located in the southern region of Mashhad city called Binaloud city with the presence of the Binaloud wind power plant and taking into account the weather conditions with the Monte Carlo simulation method and using the MATLAB software.

Keywords: Reliability - Unloaded wind power plant - Atmospheric conditions - Monte Carlo simulation

Foreword

At the end of the 18th century, with man's access to coal resources and exploitation of mines, which was a prelude to the beginning of the industrial revolution, new technologies emerged and man was able to use fossil energies to create the necessary conditions for development. Industry and better utilization of energy will get and achieve significant success. For the past few decades, a major part of the power required by the world is supplied from fossil sources such as oil and gas and nuclear energy, and after the oil embargo in 1973, renewable energy sources were widely discussed as sources of energy supply for societies[1].

In addition, the problems of using fossil energies are their damage to the environment and the limited and finite nature of fossil resources. Renewable energy sources such as solar and wind energy are clean, renewable and environmentally friendly. Dispersed production is an excellent choice for power supply of small separate system as well as remote villages and areas that cannot technically and economically provide electricity to that area according to the grid rule. But the amount of energy available from these sources depends on the following factors:

Geographical location

Land type

Altitude

Weather conditions

Therefore, the supply of electrical energy by these types of sources will be associated with fluctuations. The history of using wind as a source of energy reaches about a thousand years ago in Iran. The first horizontal axis wind turbine was used in Iran in 645 AD and it is considered a complete example of wind energy conversion device and it continued to work without change until the 12th century, that is, until the advent of windmills in Holland, France and England [2]. Environmental pollution, it is cheaper than nuclear and diesel power plants and it is free of risk can be mentioned [3].

In this thesis, with Monte Carlo sequential simulation method and using MATLAB software, the reliability of the distribution network of the city of Binaloud is presented in five chapters as follows:

The first chapter examines distributed generation and the reliability of the power system, and for this purpose, firstly, the characteristics of distributed generation, then the definition of reliability, and then the methods Its evaluation is stated.

The second chapter explains the structure of wind turbines and firstly it describes the general concepts and concepts of wind energy and then it discusses the components of wind turbines, the standards and approvals related to the turbines.

The third chapter examines the effect of weather conditions on reliability, and for this purpose it first deals with how the wind turbine works and then examines the effects of weather on the failure rate and repair time of parts. and shows the changes of wind speed in the form of a table in different seasons of the year.

In the fourth chapter, the studied system is evaluated and the reliability indicators are studied and evaluated in three cases: 1- Absence of DG [1] and no influence of atmospheric conditions 2- With the presence of DG and no influence of weather conditions 3- With the presence of DG and with the influence of atmospheric conditions.

The fifth chapter includes conclusions and suggestions.  

    Distributed production usually refers to production units that are out of dispatching command and receive money for energy production. They usually have low capacities, but this is not necessarily the case. Various technologies such as solar cells, wind turbines, fuel cells, small gas turbines, etc. It is used in scattered production units, being renewable is not its essence. For example, factories that have a source of diesel energy production, but because they have a one-way meter and do not receive money for transferring electricity to the grid, are not scattered production. Due to competition and restructuring in power systems, it is expected that small production units (distributed production) will play an increasing role in the future of these systems [5]. Many driving factors have increased the tendency to use distributed production systems. In general, these factors can be divided into five groups as follows [6].

Remarkable industrial advances in the construction and use of related technologies

Limitations in the construction of power transmission lines

Introduction of the electricity market and related issues in the power system

Increasing customer demand for high reliability service

High sensitivity regarding environmental pollution

1-1 main features of distributed resources

Distributed production has features that are discussed below [7].

1-1-1 Characteristics of distributed resources

1- Low capacity

2- Geographical dispersion

3- Renewableness of the main source

4- Decentralization of exploitation Among them

2-1-1 Advantages of using distributed resources

1-Helping the main generators during peak load

2-Reducing the need for reserve generators

3-Increasing network capacity in a shorter period of time at a lower cost

6-Increasing reliability

7-Reducing power outages for sensitive consumers

8-Improving the quality of electricity for sensitive consumers

9-More useful use of fuel

10-Reducing the cost of transmission service

11-Proposing the concept of microgrid

All the mentioned benefits are potential benefits. To achieve the actual benefits of DG, it should be:

Reliable

Dispatching ability[2]

Installed in the right place

3-1-1 Problems of using distributed sources

1-Voltage flicker (voltage changes in the range of 2 to 25 Hz and the worst case is at 18 Hz)

2-Step changes in DG output

3-Severe changes in sunlight or wind

4-Dynamic behavior of machines and their interaction with the voltage regulator

5- Harmonic production 6- Short circuit current change Load and security are the ability of the system to deal with accidents. In the traditional view, sufficiency is a possible check of the production ability and security is a definite list of inconsistent events that are considered as design criteria. In the restructured environment, there must be sufficient production taking into account the output rate of units and the reserve capacity to respond to the load, but sufficiency cannot take into account the fact that a certain production is assigned to a certain load. It is related to the transmission system.

Distributed production units can have significant positive effects on distribution networks according to the specifications and operating conditions. One of the most important effects that motivates distribution companies more than others to install and operate these units is the improvement of system reliability. So far, several studies have been presented and proposed in the field of reliability evaluation of electrical energy distribution networks, and in all of those studies, solutions have been presented to calculate the reliability indicators in the network [8].