Electrical Engineer

  Transformer on No Load Condition When the transformer is operating at no load, the secondary winding is open-circuited, which means there is no load on the secondary side of the transformer and, therefore, current in the secondary will be zero. While primary winding carries a small current I 0  called no-load current which is  2 to 10% of the rated current . This current is responsible for supplying the iron losses (hysteresis and eddy current losses) in the core and a very small amount of copper losses in the primary winding. The angle of lag depends upon the losses in the transformer. The power factor is very low and varies from  0.1 to 0.15 . The no-load current consists of two components: Reactive or magnetizing component I m (It is in quadrature with the applied voltage V 1 . It produces flux in the core and does not consume any power). Active or power component I w , also know as a working component (It is in phase with the applied voltage V 1 . It supplies t...

  Resistive Transducer Definition:   The  transducer  whose  resistance varies  because of the  environmental effects  such type of transducer is known as the resistive transducer. The  change in resistance  is  measured  by the  ac or dc measuring devices . The  resistive transducer  is used for measuring the  physical quantities like temperature, displacement, vibration etc  . The measurement of the physical quantity is quite difficult. The resistive  transducer  converts the physical quantities into variable  resistance  which is easily measured by the meters. The process of variation in resistance is widely used in the industrial applications. The resistive transducer can work both as the primary as well as the secondary transducer. The primary transducer changes the physical quantities into a mechanical signal, and secondary transducer directly transforms it into an electrical s...

  Pure inductive Circuit The circuit which contains only inductance (L) and not any other quantities like resistance and capacitance in the circuit is called a  Pure inductive circuit.  In this type of circuit, the current lags behind the voltage by an angle of 90 degrees. Contents: Explanation and Derivation of Inductive Circuit Phasor Diagram and Power Curve of Inductive Circuit Power in Pure Inductive Circuit The inductor is a type of coil which reserves electrical energy in the magnetic field when the current flow through it. The inductor is made up of wire which is wound in the form of a coil. When the current flowing through inductor changes then time-varying magnetic field causes emf which obstruct the flow of current.The inductance is measured in  Henry .The opposition of flow of current is known as the  inductive reactance . Explanation and Derivation of Inductive Circuit The circuit containing pure inductance is shown below: Circuit Diagram of pure Ind...

  Pure Resistive AC Circuit The circuit containing only a pure resistance of R ohms in the AC circuit is known as  Pure Resistive AC Circuit . The presence of inductance and capacitance does not exist in a purely resistive circuit. The alternating current and voltage both move forward as well as backwards in both the direction of the circuit. Hence, the alternating current and voltage follows a shape of the Sine wave or known as the sinusoidal waveform. Contents: Explanation of Resistive Circuit Phase Angle and Waveform of Resistive Circuit Power in Pure Resistive Circuit In the purely resistive circuit, the power is dissipated by the resistors and the phase of the voltage and current remains same i.e., both the voltage and current reach their maximum value at the same time. The resistor is the passive device which neither produce nor consume electric power. It converts the  electrical energy into heat . Explanation of Resistive Circuit In an AC circuit, the ratio of volt...

  Pure Capacitor Circuit The circuit containing only a pure capacitor of capacitance C farads is known as a  Pure Capacitor Circuit . The capacitors stores electrical power in the electric field, their effect is known as the capacitance. It is also called the  condenser . The capacitor consists of two conductive plates which are separated by the dielectric medium. The dielectric material is made up of glass, paper, mica, oxide layers, etc. In pure AC capacitor circuit, the current leads the voltage by an angle of 90 degrees. Contents: Explanation and derivation of Capacitor Circuit Phasor Diagram and Power Curve of Capacitor Circuit Power in Pure Capacitor Circuit When the voltage is applied across the capacitor, then the electric field is developed across the plates of the capacitor and no current flow between them. If the variable voltage source is applied across the capacitor plates then the ongoing current flows through the source due to the charging and discharging o...

Key Factors Affecting Transient Stability: 1. Generator Inertia: Higher inertia helps resist speed changes, improving stability. 2. Fault Clearing Time: Shorter times reduce disturbance impact, enhancing stability. 3. Excitation System: Fast-responding excitation stabilizes voltage after disturbances. 4. System Strength: High short-circuit capacity supports better stability. 5. Operating Conditions: Generators near max load are more prone to instability. 6. Transmission Reactance: Lower reactance lines improve power transfer and stability. 7. Disturbance Location/Type: Faults closer to generators are more destabilizing. 8. Network Topology: Well-connected systems with redundancy handle disturbances better. 9. Power System Stabilizers (PSS): These devices damp oscillations and improve stability. 10. Governor Response: Quick mechanical adjustments help maintain balance. 11. Renewable Integration: Low-inertia renewables reduce stability, mitigated by storage or synthetic inertia.

  DC systems also produce magnetic fields in components like inductors, motors, and electromagnets. However, reactive power is a concept specific to AC (alternating current) systems , and here's why DC systems don't have reactive power in the same sense: 1. DC vs. AC Behavior : In AC systems , the current and voltage alternate sinusoidally. As the current and voltage continuously change, inductors and capacitors store and release energy, creating a constant exchange of energy between the source and the reactive components. This exchange is what defines reactive power (Q) in an AC system. In DC systems , the current is constant (steady-state), meaning it doesn't alternate. Once a magnetic field is established in an inductor (like in a DC motor or electromagnet), the field remains constant, and there is no continuous exchange of energy between the source and the inductor, as there is in AC. Therefore, reactive power does not exist in DC . 2. Energy Storage in DC : Wh...