Transformer Turns Ratio Calculator
Calculate transformer turns ratio, secondary current, apparent power, and real power delivered. Accounts for transformer efficiency.
Formula
N = \frac{N_p}{N_s} = \frac{V_p}{V_s},\quad I_s = I_p \cdot N \cdot \eta
Reference: Faraday's Law of Electromagnetic Induction
How It Works
A transformer turns ratio describes the relationship between primary and secondary windings in an electrical transformer, determining voltage, current, and impedance transformations. The turns ratio is defined as the number of primary turns divided by the number of secondary turns, which directly influences the voltage and current scaling between transformer stages. This fundamental parameter is critical in power transmission, electrical isolation, and impedance matching applications.
Worked Example
Problem: A transformer has 500 primary turns and 100 secondary turns. Calculate the turns ratio and voltage transformation if 220V is applied to the primary winding. Solution: 1. Calculate turns ratio: Np/Ns = 500/100 = 5 2. Calculate secondary voltage: Vs = Vp × (Ns/Np) = 220V × (100/500) = 44V 3. Verify: 220V × 5 = 44V × 1 (confirms power conservation)
Practical Tips
- ✓Always verify turns ratio before designing power conversion circuits
- ✓Consider core material and winding resistance for accurate transformer modeling
- ✓Use high-quality magnetic core materials to minimize hysteresis and eddy current losses
Common Mistakes
- ✗Forgetting that turns ratio affects both voltage and current inversely
- ✗Not accounting for transformer core losses in efficiency calculations
- ✗Assuming 100% energy transfer without considering real-world inefficiencies
Frequently Asked Questions
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