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Resistors
Published in Kevin Robinson, Practical Audio Electronics, 2020
As with all components, when current flows through a resistor it heats up. The power rating indicates how much heat it can dissipate before it runs the risk of being damaged. Standard resistors can usually handle between about 125mW and 0.6W of power safely. The power ratings of standard through hole resistors are relatively modest. The three components shown in Figure 12.3 have, going from top to bottom, power ratings of 600mW, 250mW, and 125mW. The smallest of the three, at barely 3.5mm long, is a slightly less common format, and the upper two exemplify by far the most usual range of through hole resistors encountered.
Principles of Energy Conversion
Published in Hamid A. Toliyat, Gerald B. Kliman, Handbook of Electric Motors, 2018
Hamid A. Toliyat, Gerald B. Kliman
Many people who are not familiar with power electrical equipment tend to believe that this equipment is designed for a specific power rating based on abstract principles of electromagnetism. In actuality, what defines the power rating of an electrical device is its ability to expel waste heat caused by electrical and mechanical losses and its ability to operate without damage at an elevated temperature due to limitations on the rate at which it can dispose of this waste heat.
Electric Circuits and Components
Published in Quamrul H. Mazumder, Introduction to Engineering, 2018
Most electronic devices mention power rating in their datasheets that must be taken into consideration when designing a circuit. You do not want to electrically overstress your part and cause a thermal event. The power rating of a resistor gives you an idea of how much power it can dissipate in the circuit before it overheats enough to cause permanent damage. It is calculated in units of watts (W). Power dissipation can be calculated using the following mathematical formula, where V is the potential difference across the resistor and I is the current through the resistor: P=V×I=I2×=V2R
High-Power Converters and Challenges in Electric Vehicle Wireless Charging – A Review
Published in IETE Journal of Research, 2023
S. Kodeeswaran, M. Nandhini Gayathri, P. Sanjeevikumar, Rafael Peña-Alzola
An electric vehicle (EV) is an unpolluted and globally responsive alternative to the conventional combustion vehicle, which uses one or more electric motors to propel wheels with a high or low speed depending upon the condition. The requirement for electric power rating commonly defers depending on the type of vehicle. Rotary motors are mostly used for the propulsion of wheels. In tracked vehicles, linear motors are used for rotating the wheels. The EVs are operated using Lithium-ion batteries with high ratings to store electric energy. The expense and bulkiness of batteries, coupled with their lower energy densities compared to fossil fuels, make them less desirable. Moreover, charging batteries to full capacity is a time-consuming process. Currently, as the number of electrical vehicle increases, charging an EV battery with conventional methods is quite a challenging task. Due to its time-consuming charging process, new charging methods have been recently developed to avoid unnecessary problems. The most commonly used method to charge the battery is Plug-in Charging. In the plug-in method, charging power is moved from the source side to the load side through connecting wires. The wired power transfer methods have some limitations due to the possibility of current leakages, mishandling of cables, manpower, etc. Wireless charging technology is an alternative method to transfer power without any risk factors as mentioned above.
Modelling and sizing techniques to mitigate the impacts of wind fluctuations on power networks: a review
Published in International Journal of Ambient Energy, 2022
M. V. Tejeswini, I. Jacob Raglend
The simulation results show the effects of wind on system frequency by considering the effects of inertia and without inertia (Chen et al. 2017). The wind with no inertia affects the system frequency and the rate of change of frequency. Hence to maintain the system frequency within the range ESE plays an important role. The ESEs convert one form of electrical energy to some form of energy that can be stored and released when required. The following are the different types of ESEs used in grid side converters. The ESEs are classified based on the following parameters, such as power rating (MW), life span (cycles), energy capacity (MWh), efficiency (percentage), operating temperature and ramp rate (MW/min). Types of ESEs are electro-chemical storage devices, electro-magnetic storage device, mechanical energy storage devices, electro-static storage devices and vehicle to grid (Liu, Du, et al. 2016). Battery Energy Storage Equipment (BESE) are widely used in transportation and grid storage (Kim et al. 2019). ESE is referred to as the virtual inertia devices which emulate the active power from the ESEs during the disturbance conditions such as transient condition, frequency instability condition, unavailability of renewables etc. The mathematical and dynamic model of BESE (Housseini, Okou, and Beguenane 2018), Fly Wheel Energy Storage equipment (FWESE) (Díaz-González et al. 2014) and Super Conducting Magnetic Energy Storage Equipment (SCMESE) are discussed in (Du et al. 2009). ESEs used in grid side storage are divided into 4 types based on their operating characteristics.
Bidirectional EV integration in home load energy management using swarm intelligence
Published in International Journal of Ambient Energy, 2022
Sagarika Rout, Gyan Ranjan Biswal
These are the manually operated devices that are non-schedulable and consume constant power. Regarding the comfort level of the end-user, theses cannot be delayed, for example, TV, lighting system, fridge, etc. The energy consumption model for regular fixed appliances is defines as where is the total bill of connected regular devices among total connected fixed devices defined in the time interval . is the operational status of the device. is the pricing signal. is the power rating of the appliance.