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Compensation in Power System
Published in Amitava Sil, Saikat Maity, Industrial Power Systems, 2022
Power quality is essential for efficient equipment operation, and power factor contributes to this. Power factor also indicates how efficiently incoming power is used in an electrical installation. The value to which power factor to be improved so as have net annual saving is known as the most economical power factor. Power factor can be improved by installation of capacitors
Alternating Current (AC) Fundamentals
Published in S. Bobby Rauf, Electrical Engineering for Non-Electrical Engineers, 2021
DC and AC currents can also be contrasted using graphical representations, in a manner similar to the DC and AC voltage comparison conducted above. The DC and AC current functions are depicted in Figure 3.2 in a form that is similar to their voltage counterparts. The horizontal flat line represents the DC current set up by virtue of the DC voltage of the DC power source; which can be a battery or a DC power supply. The Y-axis of this current vs. time plot represents the current magnitude, I, in Amps. The DC current, in this case, is assumed to be a constant 3A. The sine waveform, oscillating about the time axis, represents the AC current, I(t), varying as a function of time, t. The peak or maximum value of the AC current, in this case is assumed to be 10A. Note that in this illustration, the AC current appears to be surfacing into the positive current territory at time t1. If one were to assume that this current was produced or driven by the voltage depicted in Figure 3.1, where the voltage broaches through the x-axis at time t = 0, one could say that the current is lagging behind the voltage. As we will explore later, in greater depth, in the power factor section, such a situation where current lags behind the voltage is said to cause a lagging power factor.
Power Measurement Equipment
Published in Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo, Electrical Power Systems Technology, 2021
Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo
Power factor is the ratio of the true power of a system to the apparent power (volts × amperes). To determine power factor, we could use a relationship of pf = W/VA. However, it would be more convenient to use a power factor meter in situations where the power factor must be monitored.
Energy saving technique for natural stone cutting machine by constant speed control in stone industry
Published in Journal of the Chinese Institute of Engineers, 2018
Ho-Chiao Chuang, Chih-Chia Chan, Wei-Bin Weng, Chen-Ta Lee
Figure 2 shows the recorded power consumption every five seconds when the sawing machine was under normal operation. Due to the forward and backward movements of the blades in the stone cutting machine, Figure 2 indicates that the magnitude of the power consumption varies considerably during the cutting process. Figure 3 shows the real-time power factor of the sawing machine as a function of time. The power factor is defined as the ratio of the real power flowing to the load to the apparent power in the circuit. The obtained power factor value is between 0.4 and 0.5 under the variations of light and heavy load. For energy-consuming equipment, such as the sawing machine, the biggest problem is the low average operating efficiency. Hence, the generated reactive power is too high, resulting in most of the electric power being wasted. Therefore, this study investigates how to improve the operating efficiency of the sawing machine without changing the motor speed and affecting the overall processing time, in order to reduce the electricity costs and achieve improvement of the energy efficiency.
Passive Island Detection Method Based on Positive Sequence Components for Grid-Connected Solar–Wind Hybrid Distributed Generation System
Published in Electric Power Components and Systems, 2023
Ch. Rami Reddy, Obbu Chandra Sekhar, B. Pangedaiah, Khalid A. Khan, Muhammad Khalid
4.2.2. Switching of Capacitor. In order to improve the power factor, the capacitor banks are linked to the distribution system. The IS detection system may malfunction due to transients created during the switching process. To assess this scenario, the inception time is set to t = 2.0 sec and increased in 10% increments until a duration of 0.02 sec is reached for 100% capacitor switching. As a result, starting at 2.5 sec, the banks are gradually lowered from 100 to 10% for the same 0.02 sec time. The suggested approach produces the corresponding IDI, as seen in Figure 10(b). Therefore, it can be observed that the presented methodology is resistant to NIS occurrences.
Multi-objective optimization of the flat burnishing process for energy efficiency and surface characteristics
Published in Materials and Manufacturing Processes, 2019
Trung-Thanh Nguyen, Le-Hai Cao, Xuan-Phuong Dang, Truong-An Nguyen, Quang-Hung Trinh
where, AP, RP, and APP denote the active power consumption, the reactive power, and the apparent power, respectively. The apparent power is the vector sum of the active power and reactive power. The active power is a significant power, which is used to perform the useful load of the device. The reactive power is a useless power but it is necessary for energy conversion. A higher value of the power factor has a significant contribution to an improvement in active power; hence, the device will produce more useful power.