Transient Over Voltages Analysis In Power System Engineering Essay

Transient Over Voltages Analysis In Power System Engineering Essay Transient over-voltage is one of main causes for unscheduled interruption in power transmission and distribution systems including a smart grid. A surge over-voltage due to lightning and switching operation results in damages in an electrical power system and often leads to power outages. Predictive calculations of over-voltages generated by the lightning and the switching operation in the transmission and distribution systems are most essential for an economical insulation design and a reliable operation of the transmission and distribution systems. The transient over-voltage can be high frequency, medium frequency or low frequency. The transient over-voltage is dangerous to both lines as well as the connected equipment and may cause damage to the equipment. This project analyzes the transient at the load after switching. This project will discuss about analyzing a transient over-voltages which is the cause and the effect of the transient over-voltages. The method to solve this tran sient over-voltages also been discussed in this project. The PSCAD simulation is used for the transient analysis in this project to design the power system circuits. Problem Statement Voltage transient in Electric Power System appear several disturbances, sometimes very dangerous for the electrical equipment life, for the environment and for the human life. Switching transient phenomena produce in Power Systems over-voltages, over-currents and electrical fields, which havent to neglect. Thus was modeling and simulated the switching transient phenomena, consequently the electric fields and the possible negative influence about electrical equipment, environment and human life. Voltage transient in power system are cause by switching operation, lightning and faults in the system. The over-voltages can be dangerous to both the lines as well as the connected equipment and may cause damage to the equipment. Purpose of this project is to analyze the transient over-voltages at the load and to identify the method to reduce the effect of transient over-voltages. 1.2 Project Objective The objective of this project is as follows: Identify the effect and the cause of transient over-voltages and also the method to solving transient over-voltages. Simulate the transient over-voltages at the load after switching and design the power system circuits by using PSCAD simulation. Analyze the result after switching and after use pre-insertion resistor. 1.3 Project Scope In order to achieve the objective of this project, there are several scopes had been outlined as follows: Analysis on the distribution system. Generating the transient over-voltages waveform by using PSCAD simulation. The analysis is just focusing into transient over-voltages that occur because of the switching capacitor. Chapter 2 2.0 Literature Review 2.1 Introduction Voltage transients in power systems are caused by switching actions, lightning and faults in the system. Different phenomena create different types of transients. Oscillatory transients are caused mainly by switching phenomena in the network. The most common switching action is capacitor bank switching. The most severe transients are caused by capacitor energizing while capacitor de-energizing only causes a minor transient. Oscillatory transients are characterized by duration, magnitude and spectral content. There are subclasses of oscillatory transients depending on the dominant frequency. In this project it will more focus on switching devices. 2.2 Power System Electric power system is a very important part of the infrastructure of modern society. The power system today is very complex interconnected network. Electric power system is the system that can transform and change the form of the energy into electrical energy and transmit it to consumer. Technology today still cannot store the electricity that has been produced. The electrical energy only produce when needed or it will use after it is produced. As the effect, the management on the electricity becomes hard and difficult. The power system may be subdivided into the four major subsystems which are Generation subsystem, Transmission subsystem, Distribution subsystem and utilize subsystem. Figure 2.1 shows the power system that divided into generation, transmission and distribution. Figure 2.1: The Electric Power System 2.2.1 Generation Subsystem There are two major components in the generation system which is generators and transformers. For generators, an essential component of power systems is the three phase alternating current, ac, generator known as synchronous generator or alternator [1]. The source of the mechanical power, commonly known as the prime mover, may be hydraulic turbines, steam turbines whose energy comes from the burning of coal, gas and nuclear fuel, gas turbines, or occasionally internal combustion engines burning oil [1]. Some alternate sources used are solar power, geothermal power, wind power, tidal power and biomass. The power transformer transfer power with very high efficiency from one level of voltage to another level [1]. The transformer is been used to step up or step down the voltage. Insulation requirements and other practical design problems limit the generated voltage to low value, usually 30 kV. The step up is used for transmission of power. At the receiving end of the transmission lines, step down transformers are used to reduce the voltage to suitable values for distribution or utilization. The electricity in an electric power system may undergo four or five transformations between generator and consumers [1]. 2.2.2 Transmission Subsystem An overhead transmission network transfer electric power from generating units to the distribution system which ultimately supplies the load. It also interconnects neighboring utilities which allow the economic dispatch of power within regions during normal conditions, and the transfer of power between regions during emergencies. The network that interconnected between the utilities and load is called system grid [2]. The transmission line can be categorized into two categories which are high voltage transmission line and sub transmission line system. The difference between these two systems is in the voltage where for the high voltage, the level for transmission line voltage can reach 500kV and for sub transmission are in between 69kV to 138kV. All the transmission will be terminated at the substation [1]. 2.2.3 Distribution Subsystem The distribution system connects the distribution substations to the consumers service-entrance equipment. The voltage for this type of system has been reduced by using step down transformer from 66 kV to 22 kV and below. The secondary distribution network reduces the voltages for utilization by commercial and residential consumers. Lines and cables not exceeding a few hundred feet in length then deliver power to the individual consumers. The secondary distribution serves most of the customers at levels of 240 V for single phase and 415 V for three phases. Distribution systems are both overhead and underground. The growth of underground distribution has been extremely rapid and as much as 70 percent of new residential construction is via underground systems [1]. 2.2.4 Utilization Subsystem The utilities system or power system loads are divided into three main categories which are industrial, commercial and residential. Industrial loads are composite loads and induction motors form a high proportion of these loads [1]. These composite loads are functions of voltage and frequency and form a major part of the system load [1]. On the other hand, commercial and residential loads consist largely of lighting, heating, air conditioning and cooking [1]. These loads are independent of frequency and consume negligibly small reactive power [1]. The load varies throughout the day and power must be available to consumers on demand. The daily-load curve of a utility is a composite of demand made by various classes of users. The greatest value of load during 24 hour period is called the peak or maximum demand [1]. 2.3 Transient Over-voltages Transient is a sudden increase in current or voltage in a circuit that can damage sensitive components and instruments. Transient overvoltages are a voltage peak with a maximum duration of less than one millisecond. It can be high, medium, or low frequency. Transient overvoltages on power system are due to various causes and can be classified into two main categories, external and internal overvoltages [3]. Natural overvoltages on low voltage networks are caused by direct lightning strikes. Lightning is an external overvoltage. The high level of energy contained in a direct lightning strike on a lightning conductor or an overhead low voltage line leads to considerable damage of the installation. The overvoltages can be over 20 times the nominal voltage. Operating or switching overvoltages linked to a networks equipment create overvoltages of a lower level 3 to 5 times the nominal voltage but occur much more frequently, thus causing premature ageing of the equipment. Switching overvol tages is an internal overvoltage. Transient overvoltages are generally oscillatory and take the form of a damped sinusoid. The frequency of these overvoltages may vary from a few hundred Hz to a few kHz and it is governed by the inherent capacitances and inductances of the circuit. 2.2 Switching Capacitor Equipment containing electronic switching components is also likely to generate electrical disturbances comparable to over-voltages. The consequences of which on sensitive equipment, albeit not visible, are no less detrimental: premature ageing and unpredictable or fleeting breakdowns. Operating over-voltages are produced when reactive or capacitive equipment is switched on and off. Furthermore, interrupting factory production, lighting or transformers can generate over-voltages which will themselves cause greater damage to nearby electrical equipment. In general, these over-voltages are caused by transient phenomena which appear when the state of the network is changed by switching operation or fault condition. Example of these over-voltages is switching on and off equipment, such as switching of high voltage reactors and switching of a transformer at no load. The time duration of the switching over-voltages is longer than lightning. This overvoltage is most disastrous to the power system equipments because it happen many time than lightning. Closing, opening, disconnection and re-striking in a power system circuit result in over-voltages six times than the normal voltage. Shunt capacitors banks are common devices used in power system for reactive power compensation, voltage regulation and power factor correction. These capacitors are implemented in the system in order to control system voltage, increase power transfer capability, reduce equipment loading, and reduce energy costs by improving power factor of the system. However, energizing these shunt capacitors produces a transient oscillation in the power systems. Due to the fact that the operation of switching shunt capacitors happens frequently, shunt capacitor switching is regarded as the main source of generating transient voltages on many utility systems. These transients can cause damages on both utility systems and customer systems, depending on the system parameters such as switched shunt capacitor size, transformer size, and the type of customer loads connected to the system. Transient frequencies due to utility distribution capacitor switching usually fall in the range 300 Hz to 1000 Hz. Transient over-voltages which result are usually not of concern to the utility, since peak magnitudes are just below the level in which utility surge protection, such as arresters, begins to operate. However, because of the relatively low frequency, these transients will pass through step-down transformers to customer loads. Secondary over-voltages can c ause voltage magnification or nuisance tripping of adjustable-speed drives. Figure 2.2 show the example of single line diagram of the power system using shunt capacitor. Figure 2.3 show the transient voltage at the switched shunt capacitor. This is the example of the transient in the voltage waveform. Figure 2.4 show the transient voltage at the low voltage capacitor that has been magnetized. Figure 2.2: Example of Single Line Diagram of the Power System Using Shunt Capacitor Figure 2.3: Transient Voltages at the Switched Shunt Capacitor Figure 2.4: Magnified Transient Voltage at the Low Voltage Capacitor 2.3 Pre-Insertion Resistor There are several techniques to mitigation the switching transient in the distribution circuit and one of the techniques that use in this project is pre-insertion resistor. A pre-insertion resistor provides a means for reducing the transient voltages associated with the energization of a shunt capacitor bank. The resistors were connected in series with the controlled capacitor bank to damp the transient inrush current. The resistor is bypassed shortly after the initial transient dissipates, thereby producing second transient event. An additional switch is use to bypass this resistor. The performance of pre-insertion resistor is evaluated using both the insertion and bypass transient magnitudes, as well as the capability to dissipate the energy associated with the event and repeat the event on a regular basis. The size for this resistor was calculated from equation 2.1 and 2.2. The optimum resistor value for controlling capacitor energizing transients depends primarily on the capacito r size and the source strength. The value of the resistor is approximately equal to the surge impedance, Zo, from equation 2.3. R = (2.1) Z = (2.2) Roptimum ≈ Z (2.3) Chapter 3 3.0 Methodology 3.1 Introduction This chapter describes about the step that needed in this project. Figure 3.1 show the block diagram of analysis and figure 3.2 show the flowchart of the process analysis. This block diagram shows the step from the first step of the project which is design the circuit to the final step which is result and analysis. Design Circuit Placing Input and Output Devices Running Simulation Result and Analysis Figure 3.1: The Block Diagram of Analysis In order to get the result from the Power System Computer Aided Design (PSCAD), the user should follow the step as follow in the Figure 3.2. Figure 3.2: Flowchart of Process Analysis 3.2 Design Circuit This is the process to build up the diagram of the circuit for the analysis. The user need to choose and selecting component from master library and put it in the main page where the user will construct the circuit. There are many components with a different type of setting. The user only need to double click on the component to edit or changes the setting and parameter. Project development consists of two parts electronic and software designs. Figure 3.2 show the three phase source that use in this project. This source impedance is type R because resistor connected series with the source. The source in this project is being controlled through fixed parameter. Figure 3.2: Three Phase Source Figure 3.3 show the three phase transformer that use in this project. The type of the transformer is a three phase and two winding transformer. The transformer is connected in star delta connection. Other characteristic for the transformer in this project is the transformer use to step up the voltage. Figure 3.3: Three Phase Transformer 3.3 Placing Input and Output Devices This process is used to get the measurement, signal and waveform of the graph in selecting part or component. The output device must be placed at the point of measurement before plotting can be done on the drawing space. Without this device, the PSCAD cannot create the plotting and the result cannot be obtained. After the circuit had already been executed and there is no error, the output from the circuit or diagram will be obtained. Figure 3.4 shows some of the output and input devices that used in this project. Figure 3.4: The input and output devices 3.4 Running Simulation After complete all the circuit design and placing input and output device, the user need to run the circuit to get the result. To run the simulation the user only need to click on the run button in the main toolbar. Figure 3.5 show the location of run button at the main toolbar. The run toolbar have a green color. When this button is pressed, PSCAD will go through several stages of processing the circuit before starting the EMTDC simulation. Figure 3.5: The run button at main toolbar During the run time, the work will be compiling by the PSCAD. The result or output only will produce if there is no error in the setting of the circuit in the drawing or all connection is connected. If there is an error, the warning will appear at output space. Once the program is no error and running, the graph and also the measurement will be produce depending on the selected node. The user also able to pause and zoomed the graph. 3.5 Graph Calculation The graph give the certain value to calculated the overshoot, resonant frequency and also the curve can be identified as an overdamped, underdamped or critical damped. Equation 3.1 is use to calculate the overshoot. Equation 3.2 is uses to calculate the resonant frequency, ωo. % OS = -100 (3.1) ωo = (3.2) The curve is overdamped if ÃŽ ± is bigger than ωo, underdamped if ÃŽ ± is smaller than ωo and critically damped if ÃŽ ± is equal to ωo. Equation 3.3 to 3.8 shows the step to get a value of ÃŽ ±. Figure 3.6 shows the example of the series RLC circuit. Figure 3.6: The Series RLC Circuit Equation 3.3 is equation for series RLC circuit. Equation 3.4 and 3.5 is a root for quadratic equation for 3.3. ( 3.3) (3.4) (3.5) The root for equation 3.4 and 3.5 can be express to equation 3.6 and 3.7. (3.6) (3.7) From equation 3.4 and 3.6, the value for damping factor, ÃŽ ±, calculated as equation 3.8. (3.8) Chapter 4 4.0 Expected Result The transient over-voltages that occur at the load during capacitor switching will be discuss base on result at all buses in the circuit that will be design before doing the simulations. The discussion is about the voltage waveform when transient over-voltages occur and voltage waveform when the simulations using pre-insertion resistors to reduce transient over-voltages. The results of waveform at all buses that will be obtain from PSCAD simulation will be discuss in term of peak voltage, overshoot and weather that waveform is overdamped, underdamped or critically damped. Figure 4.1 show the voltage waveform that will get during capacitor switching at all buses. Figure 4.2 show the voltage waveform that will get at all buses after simulate it using pre-insertion resistor. The transient will be reduce after doing the simulation using pre-insertion resistor. Figure 4.1: Transient Over-voltage Waveform at Buses. Figure 4.2: Voltage Waveform at Buses after Pre-Insertion Resistor. Chapter 5 5.0 Conclusion In PSM 1 all the literature review regarding this project are been studied so at the end of PSM 1 it can be summarized that the objectives of the project will be fulfilled in the next PSM 2, which is to design the circuit, running the PSCAD simulations and analyze the result that obtain from the PSCAD simulations in term of peak voltage, overshoot and weather that waveform is overdamped, underdamped or critically damped. This progress will need more commitment and efforts. In conjunction to achieve that, scope and objectives of this project will be the guideline.

Disabled By Wilfred Owen Essay example -- English Literature

Disabled By Wilfred Owen In my essay,"Disabled" by Wilfred Owen. I am going to describe how successfully he uses poetic techniques to present the true effects of war in his poem. The main technique used in the poem is contrast, as well as other techniques. Which makes the fate of the young man more pitiful. The use of irony, word choice, and powerful images, all create the sense of atmosphere in each stanza. The contrast of mood and tone is used in the first and second stanza, which creates a change of mood. In the first stanza words like "ghastly" and phrases like, "saddening like a hymn", are used by Owen to create a dull and depressing mood. Which represents the mans present life in which he is stuck in. Then in the second stanza words like "gay" are used to create a mood that is very happy and joyful. Which represented the mans past life, before the injury. Contrast is also related to the irony in the poem. Firstly, before his injury all the girls loved him and were fighting to get their hands on him. One of the main reasons he went to war was to "please his...

My Home Town

Belgrade is my hometown which is the largest city in Serbia and the capital. There are several tourists attraction in my hometown, such as Skadarlija, the National Museum, and across from these attractions you can find the National Theatre, Students Square, the Old Palace and several monuments, parks and other museums. The city’s nightlife is wild and exciting for those who enjoy that type of lifestyle. Many young tourists enter the city for the purpose of enjoying the grand nightlife that Belgrade offers.Very often clubs are still operating until dawn in the city and some of the most popular places of interest is the barges that is spread out by the banks of the Sava and Danube Rivers. Belgrade, Serbia is the home of the main head quarters of the national broadcaster Radio-Television Serbia-RTS. They are currently trying to convert this to a public service broadcaster. You can also find the RTS music publishing operation in my hometown. You can find incredible architectural d esigns in Belgrade. There are still Oriental buildings standing in the city spread out over the city.You can also find more modern styles of designs for buildings and homes, which are just as spectacular. Belgrade has a transport system that consists of trams, trolleybuses and regular buses that carry people across the city. Belgrade, Serbia is the twin city to Chicago, Illinois and I guess you can guess that these two cities have much in common. Both cities are extremely busy and offer the residents and visitors many places to visit. Sports are very popular in my hometown. There are too many sports facilities to count and some have said that there is close to 1,000 facilities where sports are played.My city hosted many great sports events, such as the 2005 European Volleyball Championship, the 2005 Eurobasket and the 2006 European Water polo Championship. In the year 2007, Belgrade Serbia will host the European Youth Olympic Festival and in the year, 2009, they will host the Summer Universaide, which was a huge honor since it was selected over other countries, like Poznan and Monterrey. We have two great football clubs which are Red Star Brigade and FK Partisan, along with other first league clubs. Belgrade houses the Marakana, or the Red Star Stadium, which is a major stadium in the city and we also have the Partizan Stadium.Belgrade is the home of the Belgrade Arena where basketball matches are held. You can also find the Pionir Hall and the Tasmajdan Sports Center, where water polo matches are played. We have two state universities in Belgrade and many private schools throughout our city. One of the oldest educational institutions in our city of Belgrade is the Teacher’s College which dates back to the year, 1689. The economy in Belgrade, Serbia has been getting better since the year, 2000. The internationally imposed Trade Embargo caused the economy to decline for a long period of time, in the 1990s.In Belgrade, you will discover many Serbs, Croats , Muslims, Roma, Yugoslavs and Montenegrins. Many of the residents of Belgrade, came from other countries who were seeking a better way of life for themselves and their families. Some of these people ran from their countries as refugees from war and ethnic cleansing. Belgrade is divided into subdivisions. There are 17 municipalities, 10 that have urban status and seven that have suburban status. You can find that most of the municipalities are located on the southern area of the rivers, which are the Danube and the Sava, located in the Sumadija area of Belgrade, Serbia.Most of these municipalities can be found on the south side of the Danube and Sava Rivers. There are three municipalities, which are the Novi Beograd, the Zemun and the Surcin which can be found on the north side of the Sava River, in the Syrmia area of Belgrade. The municipality of Palilula is located on both banks of the Danube River, which is located in the Sumadija and Banat areas, in Serbia. Belgrade has a modera te, continental climate. The hottest month in Belgrade is July and the second hottest month would be August.In these two months, the sun shines for an average of ten hours a day, unlike the months of December and January, which on receive two to three hours of sunshine per day. My hometown of Belgrade has received many prestigious honors, such as the French Legion of Honor, the Serbian Karadorde’s Star with Swords, the Czechoslovak War Cross and the former Yugoslavian Order of the National Hero. In the year, 2006, Belgrade was awarded the incredible title of â€Å"City of the Future of Southern Europe† by the Financial Times of London. This award was quite an honor for the entire city of Belgrade.

WW1 and WW2 Germany, Adolf Hitler, Nazi Archduke Franz Ferdinand - Free Essay Example

Sample details Pages: 7 Words: 2157 Downloads: 1 Date added: 2019/06/18 Category People Essay Level High school Tags: Adolf Hitler Essay World War 1 Essay World War 2 Essay Did you like this example? As for the Origin of this article, it doesnt state who created it, when was it created, or where did it come from but the Purpose of this article was to inform people who were curious as to how Adolf Hitler and the rise of his nazi party caused World War 2. This article describes how Hitler grew to be one of the most powerful and infamous dictators of the 20th century. Students would be the intended audience because its a simple article that doesnt use strong vocabulary and it gives you more than enough facts to understand how Hitler was one of the root causes to World War 2. Don’t waste time! Our writers will create an original "WW1 and WW2: Germany, Adolf Hitler, Nazi Archduke Franz Ferdinand" essay for you Create order The Content of this article establishes how Adolf Hitler, the leader of Germanys nazi party capitalized on economic woes, popular discontent, and political infighting to take full power in Germany in 1933 which helped Germanys invasion of Poland in 1939 and led to the outbreak of World War 2. It also establishes that by 1941 nazi forces took over most of Europe. The Value of this origin is that this article wasnt written during Hitler and his nazi party were taking over, this was written after. If this article was written during the time Hitler and his nazi party were taking over, it would be more convenient because there would be information from somebody who went through and experienced the rise of Hitler and his nazi party first hand. A positive value about this article is that whoever wrote it provided more information than needed. They talked about the actual rise of Adolf Hitler. The author talked about the day he was born, his service in World War 1 and how he later rose to be involved in World War 2. The Limitations of this article is that theres no author. The article didnt provide a date on when it was created, who created it, and where did the source come from. Also, another limitation is that the article wasnt written from first hand experience meaning that the author didnt get to experience first hand what was actually happening when Hitler and his nazi party rose to cause WW2. Causes of WW2 This article also doesnt provide any Origin. It doesnt say who created it, when was it created or where did the source come from. The Purpose of this article is to inform readers of the many causes of World War 2 and how Hitler and his nazi party were one of the main ones. This article contains how Hitler offered Germany hope thus becoming the leader and dictator of Germany. Adolf Hitler then allied Germany with Mussolini and Italy then he looked to restore Germany to power by increasing his domain by taking over Australia in 1938. The intended audience of this article would be anyone whos interested in the causes of WW2 because the article talks about many or all causes of WW2 in great detail thats not hard to understand. The Content of this article establishes how Adolf Hitler, Germany, and his Nazi party were in many of the causes to WW2. When Hitler took over Australia in 1938, the League of Nations did nothing to stop him therefore Hitler grew bolder and took over Czechoslovakia in 1939. This article also establishes appeasement. After WW1 the European nations didnt want another war while other countries such as Italy and Germany became hostile and started to take over many other countries and worked to build up their army, Britain and France hoped to keep peace through appeasement. Basically, they tried to make Hitler and Germany happy instead of trying to stop him. They hoped that he would be happy and that there wouldnt be a war but appeasement failed and it only made Hitler bolder. The Value of this article illustrates that this article wasnt written when any of the causes were taking place, if this article was written by someone who went through some of the causes, there would be more accurate information because it would be first hand by someone who actually went through it. A positive value is that the article has almost every single cause of WW2. Most of the causes have to deal with Hitler, Germany, and Hitlers nazi party. Which gives a better var iety of reasons as to why Hitler was one of the main causes for WW2. The Limitations of this article is also that it doesnt provide the reader with a author, a date on when it was created, or where the source came from. Also, it could have also been written or influenced by someone who went through the experiences first hand. Investigation To ask why Hitler and the Nazi party came in to power, one must first look back to the Great War or as we now know as the first world war. On June 28, 1914 Archduke Franz-Ferdinand was assassinated while visiting the Bosnian capital of Sarajevo. The first assassination attempt on his life had come hours earlier when the group of assassins missed Ferdinand s convoy but the explosive that went off injured many. When Ferdinand visited those injured in the hospital later that day, the motorcade took a wrong turn and Gavrilo Princip shot and killed Ferdinand. As Ferdinand was the heir to the Austrian-Hungarian Empire throne, there was a lot of violence following his murder. Most violence was Anti-Serb. In late June 1914, Austria-Hungary declared war on Serbia. Germany then occupied Luxembourg ,declared war on France and Invaded a neutral Belgium. This outraged Britain which then declared war on the aggressive Germans on August 4th, 1914. This pitted 6 of the worlds powers against each oth er as the allied powers were spearheaded by the British Empire, Russia, and France while the Ottoman Empire, Austria-Hungary, and the German Empire were their counterparts. As the war raged in Europe, many people lost their lives ranging anywhere from those in the trenches to innocent civilians. Once all was said and done, more than nine million people lost their lives. Countries were given reparations for their part in the war. Germany was instructed to pay $33 billion dollars. This led to much outrage from the public. In order to pay off the reparation cost, Germany had to receive loans from other countries. This buried the country under more debt. People felt as if they needed a voice and the man to provide it was no other than Adolf Hitler. By 1930, Adolf Hitler was a politician who was trying to have a bigger role in Germany. Once the Great Depression was in full swing, Hitler took advantage of the appalling situation and used it as a political opportunity to gain political power. He ran for president in 1932 but lost to Paul Von Hindenburg. Hitler did gather a large amount of votes but not to the level as Hindenburg. Franz Von Papen, Alfred Hugenberg and several more wealthy businessmen signed off their support of Hitler through letters to the president. They wanted Hitler to be appointed chancellor. Hindenburg later, reluctantly appointed him as chancellor of Germany. Hitler worked to subdue any leftist movement and sought a nationalist and fascist government. Hitler withdrew from the League of Nations. Along with this, Hitlers actions would break several treaties signed at the end of World War 1. Hitler then executed a foreign policy act that prepared the country for war. By this time Germany had signed an axis wit h Italy and a pact with Japan. These 3 would form what we now call the Axis Powers during the second world war. Afterwards, he would unite Austria and Germany. Then on September 1, 1939, Germany invaded Western Poland to kick start the war. The second world war is a direct consequence of the first world war due to unsettled tensions and anger from that dispute. Adolf Hitler rose to power during World War 1. On June 28th, 1919 the Treaty of Versailles was signed at the end of World War 1 which ended the war between Germany and the allied powers. The Treaty of Versailles required Germany to admit all the guilt for the war and also required Germany to pay for the damage the war had cost to the allies. Germany had to accept the fact that they had to take full responsibility that they started World War 1. When Hitlers Nazi Party got into power, he believed that Germany shouldve won the first world war. He also believed that Germany gave in too easily, this caused his desire for revenge on the allied powers. World War 2 started September 1, 1937 and ended September 2, 1945. Hitler and his nazi party played a major role into beginning the war. In January 1933, Adolf Hitler came to power in Germany and began to challenge the Treaty of Versailles. Which he adapted an aggressive foreign policy that later led to the war. Germanys invasion of Poland also led to the outbreak of World War 2. Hitler believed the German race needed more room to live because of their growing population. Because Hitler believed the Germans as the superior race, Hitler claimed that they were eligible to take the land of Eastern Europe. The Treaty of Versailles prohibited rearmament. When Hitler came to power in 1933 he began rearming between 1932 and 1939 which increased his army. Hitlers move was to put his German troops back Western Germany which broke the Treaty of Versailles and might have provoked war with Britain and France. Hitler knew his army wasnt strong enough but he also knew Britain and France were preoccupied with another crucial issue. Mussolini had invaded Abyssinia and the British and French were busy trying to avoid war. On March 7, 1936 a weak German army marched into Western Germany (the Rhineland) to see if th e French and British would do anything but they didnt. In March 1939 Germany invaded the Czechoslovakia and took over the capital Prague. Britain saw this as an act of aggression and decided that Hitlers expansion had to stop. On September 1st 1939, Germany invaded Poland which began the war between Germany and Poland. Between 1933 and 1945 Nazi Germany began the persecution and obliteration of Jews in in Europe also known as the Holocaust. Germans saw Jews as a threat to their own. Nazi Germany murdered 6 million Jews and over 1 million homosexuals, jehovah witness, and anyone below the German race. This also sparked a war between Germany and Europe. In conclusion, to talk about the causes that Hitler and his Nazi Party did to lead up to World War 2 couldnt of have been brought up or talked about without bringing up World War 1 and Hitlers taste for revenge. Out of anger caused by the allied powers, he retaliated causing the second World War. This investigation talks about in detail, Hitler and Hitlers Nazi Partys involvement and cause of World War This investigation has allowed me to learn some of the methods used by historians, as well as the challenges they face. A historians job is to study and interpret the past. They use tools that could be primary or secondary. Historians use evidence from primary and secondary sources to answer their questions and they have to choose which information is more trustworthy and important as evidence.The methods used by historians that I used in my investigation was using primary and secondary sources to find out which information was important and trustworthy. I had to find information that went specifically with my investigation so I could persuade and inform the reader and also stick to my topic. A challenge that historians face are the sources. Historians have to determine the credibility of sources and the information they give. Historians also deal with the problem of finding enough information in a source to use for their investigation. The challenges for a historian differs from a scientist or a mathematician because if a scientist or a mathematician messes up somewhere along the problem, that simple mistake could destroy the whole problem itself. So a challenge scientist and mathematicians have to face a lot is doubt while historians face determining whether or not the source is reliable so they wont put out false information. My investigation highlighted out many limitations to these methods. A limitation to one of these methods is the difficulty in being unbiased when providing information in choosing different historical events and in determining their importance. History itself is 100% accurate, the historical source has a limitation on its ability to convey accurate knowledge and an understanding of history. A historical source only provides a very small portion of what actually occurred in history so my knowledge and understanding of history would be limited. Another limitation is the bias of the historian. If a historian isnt bias when writing about a subject, he is still prone to accidental errors and it doesnt mean that his sources were wrote unbiased. This is a limitation my investigation highlighted out of me because even though I mightve rose above my biases while writing about my investigation, that doesnt mean the sources I chose were unbiased. Also, if my sources happened to be unbiased, the y could still be open to accidental errors.