Watkins-Johnson Converter using MATLAB

Introduction

MATLABSolutions demonstrate In this particular task, step-by-step guide to The Watkins-Johnson (WJ) converter is a type of DC-DC converter that employs a tapped inductor, providing an extra degree of freedom compared to classical converters like the buck converter. Here’s a step-by-step explanation of how it works:

Basic Concept

The WJ converter is designed to step down (buck) or step up (boost) the input voltage using a tapped inductor. The tapped inductor allows for more flexibility in the voltage conversion process.

Components

The main components of the WJ converter include:

• Tapped Inductor: An inductor with a tap point that divides the inductor into two sections.
• Switch (Transistor):Controls the connection between the input voltage and the inductor.
• Diode: Allows current to flow in one direction, preventing backflow.
• Capacitor: Smooths out the output voltage.
• Load: The device or circuit that receives the output voltage.

Operation Modes

The WJ converter operates in two main modes: continuous conduction mode (CCM) and discontinuous conduction mode (DCM).

Continuous Conduction Mode (CCM)

In CCM, the current through the inductor never falls to zero. The operation can be divided into two phases:

1. Switch On: When the switch is closed, the input voltage is applied across the inductor, causing the current to increase. The inductor stores energy during this phase.
2. Speed Control Loop: The middle loop, which controls the motor’s speed.
3. Switch Off: When the switch is open, the inductor releases its stored energy through the diode to the load and the capacitor.

Discontinuous Conduction Mode (DCM)

In DCM, the current through the inductor falls to zero during part of the switching cycle. This mode typically occurs under light load conditions.