Example #6 Buck Converter with Simplorer Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish.

Buck Converter Design Process 1) Manually select the topology 2) Use Simplorer to simulate the SMPS model 3) Use PExprt to design inductor 4) Use PEmag to generate detailed netlist model 5) Import PEmag model into Simplorer 6) Use Simplorer to simulate the PEmag model 7) Use Simplorer (transient) for load step test 8) Use Simplorer (AC) to design feedback loop 9) Use Simplorer (transient) to do feedback loop test and verify performance SimplorerPExprt PEmag Simplorer

Step 1: Select the topology Buck Converter Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Decide to use either average or switch level Buck Converter

Step 2: Simulate in Simplorer with SMPS library Use switch level Buck Converter from SMPS library Change duty cycle and inductor value to achieve desired output voltage Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Open e06a_Buck.SSH

Step 3: Design Inductor with PExprt Easy transition from Simplorer to PExprt Build a waveform based inductor or buck converter in PExprt Open e06b_Buck.cia Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish.

Step 3 (cont): Design Inductor with PExprt Run the PExprt model and select the design you prefer Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. PExprt design results, including constructive data

Step 4: Generate Model with PExprt Modeler [PEmag] Generate a 1D Analytical or a 2D FEA based model Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Can include core non-linear effects using Jiles-Atherton model if the core is operating in the nonlinear range (usually this is a bad design) Open e06c_Buck.pmg

Step 5: Import PExprt Model into Simplorer Use Simplorer PExprt link to substitute ideal inductor with PExprt model Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish.

Step 6: Simplorer Simulation With PExprt Model PExprt Model and Symbol Simulate the PExprt model in Simplorer Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Open e06d_Buck.SSH

Step 7: Load Step Test: Feedback loop is needed reduces current and device moves to discontinuous mode Non-Regulated Output Voltage Spike occurs since no control loop is used Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Open e06e_Buck.SSH

Step 8: Design Feedback Loop in frequency domain This controls duty cycle of switch to maintain constant output voltage Add PID controller from the SMPS library Design of the control loop with AC analysis of the Converter Specifically, select R and C in the PID controller Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Open e06f_Buck.SSH

Step 9: Feedback Loop Test: Simplorer Time Domain Finally, return to the time domain analysis to see how the buck converter performs PID regulator from the SMPS library Load Step Regulated Output Voltage Designing a new 42-volt automotive power system requires knowledge of components, electronics and controls. It has become a truly multi-disciplinary engineering task. Ansoft's Electromechanical System Design Suite is a powerful combination of software simulation technology including electromagnetics, circuits, block diagrams, state machines, and specialized design programs which allow an engineer to successfully design and analyze a complete 42V system from start to finish. Open e06g_Buck.SSH