Tag Archives | Power System

Voltage: Variation, Imbalance and Fluctuations | Electrical Engineering

In this article we will discuss about:- 1. Long Duration Voltage Variations in Power System 2. Short Duration Voltage Variations in Power System 3. Voltage Imbalance 4. Voltage Fluctuations. Long Duration Voltage Variations: It is defined as "Long-duration variations encompass root-mean-square (rms) deviations at power frequencies for longer than 1 min." ANSI C84.1 specifies the steady-state voltage tolerances expected on [...]

By |2017-12-28T10:24:59+05:30December 28, 2017|Voltage|Comments Off on Voltage: Variation, Imbalance and Fluctuations | Electrical Engineering

Transients and Its Classification | Power System | Electricity

A transient can be a unidirectional impulse of either polarity or a damped oscillatory wave with first peak occurring in either polarity. The term transients has been used in the analysis of power system variations to denote an event that is undesirable and momentary in nature. The notion of a damped oscillatory transient due to an RLC network is probably [...]

By |2017-12-28T10:24:59+05:30December 28, 2017|Transients|Comments Off on Transients and Its Classification | Power System | Electricity

Waveform Distortions in Voltage or Currents | Electrical Engineering

Waveform distortion is defined as a steady-state deviation from an ideal sine wave of power frequency principally characterized by the spectral content of the deviation. There are five primary types of waveform distortion: 1. DC Offset 2. Harmonics 3. Interharmonics 4. Notching 5. Noise. Type # 1. DC Offset: The presence of a dc voltage or current in an ac [...]

By |2017-12-28T10:24:59+05:30December 28, 2017|Distortions|Comments Off on Waveform Distortions in Voltage or Currents | Electrical Engineering

Computation of Voltage Sag Performance | Power System

There are two possible locations for faults on the distribution systems, i.e., on the same feeder and on parallel feeders. An area of vulnerability defining the total circuit miles of fault exposures that can cause voltage sags below equipment sag ride- through capability at a specific customer needs to be defined. The computation of the expected voltage sag performance can [...]

By |2017-12-28T10:24:58+05:30December 28, 2017|Voltage|Comments Off on Computation of Voltage Sag Performance | Power System

Voltage Sag: Sources and Interruptions | Electrical Engineering

In this article we will discuss about:- 1. Sources of Voltage Sags 2. Area of Vulnerability 3. Equipment Sensitivity 4. Interruptions 5. Performance Evaluation 6. Protection. Voltage sag is a short duration (typically 0.5 to 30 cycles) reduction in rms voltage caused by faults on the power system and by the starting of large loads, such as motors. Momentary interruptions [...]

By |2017-12-28T10:24:58+05:30December 28, 2017|Voltage|Comments Off on Voltage Sag: Sources and Interruptions | Electrical Engineering

Improving Voltage Sag Performance (Technologies) | Electrical Engineering

The following points highlight the major technologies available for improving voltage sag performance. The technologies are: 1. Ferroresonant Transformers 2. Magnetic Synthesizers 3. Active Series Compensators 4. On-Line UPS 5. Standby UPS 6. Hybrid UPS 7. Motor-Generator Sets 8. Flywheel Energy Storage Systems and a Few Others. 1. Ferroresonant Transformers: Ferroresonant transformers, also called constant voltage transformers (CVTs), can handle [...]

By |2017-12-28T10:24:57+05:30December 28, 2017|Voltage|Comments Off on Improving Voltage Sag Performance (Technologies) | Electrical Engineering

Harmonics: Phase Rotation and Phase Angle Relationship | Power System

In a three-phase power system, the harmonics of one phase have a rotational and phase angle relationship with the harmonics of the other phases. In power system studies involving harmonics, this relationship is important. In a balanced three-phase electrical system, the voltages and currents have a positional relationship as shown in Fig. 4.6. The three voltages are 120° apart and [...]

By |2017-12-28T10:24:55+05:30December 28, 2017|Harmonics|Comments Off on Harmonics: Phase Rotation and Phase Angle Relationship | Power System

Effect of Harmonics on Power System Devices | Electrical Engineering

The topic of harmonics is interesting because of the harmful effects they have on power system devices. What makes harmonics so insidious is that very often the effects of harmonics are not known until failure occurs. Insight into how harmonics can interact within a power system and how they can affect power system components is important for preventing failures. In [...]

By |2017-12-28T10:24:55+05:30December 28, 2017|Harmonics|Comments Off on Effect of Harmonics on Power System Devices | Electrical Engineering

Transient Waveforms of Voltage: Top 7 Examples | Electrical Engineering

The following points highlight the seven main examples of transient waveforms of voltage. The examples are: 1. Motor Start Transient 2. Power Factor Correction Capacitor Switching Transient 3. Medium Voltage Capacitor Bank Switching Transient 4. Voltage Notch due to Uninterruptible Power Source Unit 5. Neutral Voltage Swing 6. Sudden Application of Voltage 7. Self-Produced Transients. Example # 1. Motor Start [...]

By |2017-12-28T10:24:55+05:30December 28, 2017|Voltage|Comments Off on Transient Waveforms of Voltage: Top 7 Examples | Electrical Engineering

Over-Voltage: Sources and Protection | Electrical Engineering

In this article we will discuss about the sources of over-voltage and its protection. Sources of Over-Voltage: Transients are disturbances that occur for a very short duration (less than a cycle) and the electrical circuit is quickly restored to original operation provided no damage has occurred due to the transient. An electrical transient is a cause-and-effect phenomenon. For transients to [...]

By |2017-12-28T10:24:55+05:30December 28, 2017|Over-Voltage|Comments Off on Over-Voltage: Sources and Protection | Electrical Engineering
Go to Top