Inductors Explained - The basics how inductors work working principle
Inductors: Understanding Their Function and Importance
What is an Inductor?
- An inductor is a component that stores energy in its magnetic field and can release it almost instantly, making it crucial for various circuits.
Analogy of Water Flow
- The operation of an inductor can be understood through the analogy of water flowing through pipes, where the pump represents a battery, and the pipes symbolize electrical wires.
- A reducer in one branch of the pipe signifies resistance, while a water wheel in another branch represents the inductor, which takes time to start moving due to its inertia.
Behavior During Circuit Operation
- Initially, when power is applied, water (or current) prefers to flow through paths with less resistance; thus, it bypasses the water wheel (inductor) until it gains speed.
- Once the water wheel reaches maximum speed, it offers little resistance allowing more flow through this path instead of the reducer. When power is turned off, inertia keeps the wheel spinning temporarily.
Inductor's Role with Resistive Loads
- In circuits where an inductor is connected parallel to a resistive load (like a lamp), initially very little current flows through the inductor due to high resistance. As time passes and resistance decreases, current shifts towards the inductor causing the lamp to turn off.
- After disconnecting power supply, inductors continue pushing electrons around until energy dissipates through resistance within the circuit components like lamps.
Magnetic Field Generation
- Passing electrical current through a wire generates a magnetic field observable by using compasses placed around it; reversing current direction also reverses this magnetic field alignment.
- Wrapping wire into coils enhances this effect as individual magnetic fields merge into one powerful field capable of storing energy when electricity flows through it. Upon cutting power supply, this stored energy converts back into electrical energy pushing electrons along again rapidly during collapse of magnetic field.
Inductance and Back EMF
Inductor Behavior and Characteristics
Understanding Inductor Functionality
- Current flowing through an inductor generates a magnetic field that gradually increases, allowing more current to flow as the back EMF fades away. Eventually, the magnetic field stabilizes, and the inductor behaves like a regular wire.
- When an easier path for electrons is available through the inductor compared to a lamp, the lamp will not shine as electrons preferentially flow through the inductor. The inductor attempts to maintain constant current when power is cut by pushing out electrons.
- The energy stored in the magnetic field from electron flow converts back into electrical energy to stabilize current flow. However, this magnetic field only exists while current flows; it collapses as resistance increases.
Visualizing Inductor Behavior
- Observing an oscilloscope connected to separate circuits with resistors and inductors reveals distinct behaviors: resistors show an instant vertical plot when current flows, while inductors display a gradual increase forming a curved profile before stabilizing.
- Stopping current through a resistor results in an immediate drop back to zero on the oscilloscope. In contrast, stopping current through an inductor leads to a gradual decrease represented by another curved profile down to zero.
Physical Characteristics of Inductors
- Inductors typically consist of copper wire coiled around a cylinder or ring. Some designs include casings that shield their magnetic fields from interfering with other components.
- Engineering drawings represent inductors with specific symbols. Any coiled wire can function as an inductor, including components like motors and transformers.
Applications of Inductors
- Inductors are utilized for various purposes: boosting DC output voltage while reducing current (boost converters), filtering AC signals (allowing only DC), and separating different frequencies. They are also essential for transformers, motors, and relays.
Measuring Inductance
- The unit of measurement for inductance is Henry (H); larger values indicate higher inductance capacity for energy storage and longer time required for magnetic field buildup.