DC Current Source Design & Simulation
Budget: $750 – $1,500 AUD
Project Description:
I am seeking assistance with a project: designing and simulating a Switch Mode DC Current Source. The goal is to create a power supply suitable for electrolysis (rust removal), with the following key specifications:
* Output: Adjustable Constant Current, 0 - 10A DC
* Maximum Output Voltage: 30V DC
* Control: Closed-loop feedback control to maintain set current.
* Topology: Switch Mode (likely Buck converter based on initial work).
* Input Voltage: 48 volts
I have already started a basic open-loop buck converter simulation in LTSpice (schematic available) but need expert help to develop it into a functional, stable, closed-loop adjustable current source simulation. This project will eventually involve building a prototype (within a component budget of approx. $300 AUD as per original project spec), but this freelance task focuses primarily on the simulation and design choices first.
Scope of Work & Required Skills:
I am looking for a freelancer with proven expertise in:
* Power Electronics: Strong understanding of DC-DC converters, especially buck topology.
* LTSpice: Proficiency in simulating SMPS circuits, including control loops, component parasitics (ESR, DCR), and stability analysis.
* Control Systems: Experience designing/simulating stable closed-loop feedback systems (specifically current control is a plus). Understanding of Gain/Phase margins.
* Component Selection: Knowledge of selecting appropriate MOSFETs, diodes, inductors, capacitors, controller ICs, gate drivers, and sense resistors for power applications.
* (Optional for later milestones): PCB layout principles for SMPS, prototype testing.
Freelancer Tasks (Milestone Based):
* Milestone 1: LTSpice Simulation (Budget: 100 AUD)
* Review my existing LTSpice simulation file.
* Develop and deliver a functional, stable, closed-loop LTSpice simulation of the adjustable current source meeting the 0-10A / 30V max specs.
* Implement current sensing and a suitable control loop (e.g., using behavioral models or standard op-amps/comparators).
* Include realistic component models (e.g., MOSFET with correct parameters, diode, inductor with DCR, capacitor with ESR, gate driver if needed).
* Demonstrate basic stability (e.g., stable output current waveform in transient analysis, response to load/setpoint changes). Provide brief simulation plots/notes.
* Provide brief commentary on the chosen control strategy and key component values in the simulation.
* Milestone 2: Design Choices & Component Selection (Optional - Scope & Budget TBD)
* Provide recommendations for specific, readily available components (Controller IC, MOSFET, Diode, Inductor, Capacitors etc.) suitable for the prototype build, considering performance and budget ($300 AUD component limit).
* Assist with refining the schematic based on chosen components.
* Milestone 3: PCB Layout Guidance (Optional - Scope & Budget TBD)
* Provide guidance or review of PCB layout, focusing on best practices for SMPS (critical loops, grounding, thermal management).
* Milestone 4: Prototype Build/Test Support (Optional - Scope & Budget TBD)
* Provide advice on build sequence and testing procedures.
What I will provide:
* My current LTSpice simulation file.
* The original project proposal document (PDF).
* Prompt clarification on requirements.
Required Qualifications & Application:
* Please provide examples of previous work or experience specifically related to SMPS design and simulation, particularly buck converters or current sources.
* Strong communication skills are important.
* Please only apply if you have demonstrable expertise in power electronics simulation and design.
Deadline: Please propose a timeframe for completing Milestone 1.
I am seeking assistance with a project: designing and simulating a Switch Mode DC Current Source. The goal is to create a power supply suitable for electrolysis (rust removal), with the following key specifications:
* Output: Adjustable Constant Current, 0 - 10A DC
* Maximum Output Voltage: 30V DC
* Control: Closed-loop feedback control to maintain set current.
* Topology: Switch Mode (likely Buck converter based on initial work).
* Input Voltage: 48 volts
I have already started a basic open-loop buck converter simulation in LTSpice (schematic available) but need expert help to develop it into a functional, stable, closed-loop adjustable current source simulation. This project will eventually involve building a prototype (within a component budget of approx. $300 AUD as per original project spec), but this freelance task focuses primarily on the simulation and design choices first.
Scope of Work & Required Skills:
I am looking for a freelancer with proven expertise in:
* Power Electronics: Strong understanding of DC-DC converters, especially buck topology.
* LTSpice: Proficiency in simulating SMPS circuits, including control loops, component parasitics (ESR, DCR), and stability analysis.
* Control Systems: Experience designing/simulating stable closed-loop feedback systems (specifically current control is a plus). Understanding of Gain/Phase margins.
* Component Selection: Knowledge of selecting appropriate MOSFETs, diodes, inductors, capacitors, controller ICs, gate drivers, and sense resistors for power applications.
* (Optional for later milestones): PCB layout principles for SMPS, prototype testing.
Freelancer Tasks (Milestone Based):
* Milestone 1: LTSpice Simulation (Budget: 100 AUD)
* Review my existing LTSpice simulation file.
* Develop and deliver a functional, stable, closed-loop LTSpice simulation of the adjustable current source meeting the 0-10A / 30V max specs.
* Implement current sensing and a suitable control loop (e.g., using behavioral models or standard op-amps/comparators).
* Include realistic component models (e.g., MOSFET with correct parameters, diode, inductor with DCR, capacitor with ESR, gate driver if needed).
* Demonstrate basic stability (e.g., stable output current waveform in transient analysis, response to load/setpoint changes). Provide brief simulation plots/notes.
* Provide brief commentary on the chosen control strategy and key component values in the simulation.
* Milestone 2: Design Choices & Component Selection (Optional - Scope & Budget TBD)
* Provide recommendations for specific, readily available components (Controller IC, MOSFET, Diode, Inductor, Capacitors etc.) suitable for the prototype build, considering performance and budget ($300 AUD component limit).
* Assist with refining the schematic based on chosen components.
* Milestone 3: PCB Layout Guidance (Optional - Scope & Budget TBD)
* Provide guidance or review of PCB layout, focusing on best practices for SMPS (critical loops, grounding, thermal management).
* Milestone 4: Prototype Build/Test Support (Optional - Scope & Budget TBD)
* Provide advice on build sequence and testing procedures.
What I will provide:
* My current LTSpice simulation file.
* The original project proposal document (PDF).
* Prompt clarification on requirements.
Required Qualifications & Application:
* Please provide examples of previous work or experience specifically related to SMPS design and simulation, particularly buck converters or current sources.
* Strong communication skills are important.
* Please only apply if you have demonstrable expertise in power electronics simulation and design.
Deadline: Please propose a timeframe for completing Milestone 1.