Solar-Powered VFD Control System for HVAC Compressor with Battery Charging (PLC-Based)

Job ID: 40127334

Budget: ₹37,500 – ₹75,000 INR

Title
Solar-Powered VFD Control System for HVAC Compressor with Battery Charging (PLC-Based)

This project focuses on control system design and power management logic, not physical solar panel installation.

Project Description

We are seeking an expert-level electrical systems engineer / controls engineer to design a solar-powered Variable Frequency Drive (VFD) system that operates an AC HVAC compressor while simultaneously managing battery charging and power flow.

This is not a theoretical or academic exercise. The outcome must be an industrial-grade, implementation-ready control architecture suitable for real-world HVAC deployment.

The system will intelligently coordinate:

Variable solar input

Battery charging and protection

VFD-driven compressor operation

Load prioritization and fault handling

The core control platform will be PLC-based, with ladder logic preferred, and Modbus communication to the VFD. The design must prioritize reliability, efficiency, and system protection under fluctuating solar and load conditions.

This is a one-time, fixed-price engagement with a fast-moving timeline. An NDA is mandatory prior to sharing detailed system parameters.

Required Skills & Experience

Only apply if you have direct, hands-on experience in the following areas:

PLC Programming

Ladder logic (required)

Industrial control standards

State-based logic and fault handling

VFD Systems

Configuration and commissioning

Modbus RTU/TCP control and monitoring

Compressor motor control (torque, ramping, protection)

HVAC & AC Compressors

Compressor operating characteristics

Start/stop logic, safety interlocks, and efficiency considerations

Solar Power & Energy Storage

PV power utilization strategies

Battery charging algorithms

DC/AC power flow management and prioritization

System Engineering

Electrical architecture design

Protection strategies (over/under-voltage, current, thermal, fault states)

Clear technical documentation suitable for build and testing

⚠️ This project is not suitable for entry-level PLC programmers or generalist freelancers. Demonstrated experience with similar systems is essential.

Deliverables

The selected freelancer will deliver complete, implementation-ready documentation, including:

Overall system architecture and power flow design

Control strategy detailing operating modes and transitions

PLC ladder logic (or fully documented equivalent)

VFD configuration parameters and Modbus register mapping

Battery charging and solar prioritization logic

Fault handling, protections, and efficiency considerations

Clear documentation sufficient for integration, testing, and commissioning

Budget & Timeline

Budget: Fixed price (to be agreed based on qualifications and scope clarity)

Timeline: ASAP
Preference given to freelancers who can start immediately and deliver efficiently without compromising quality.

NDA Requirement

A Non-Disclosure Agreement is mandatory.
You must be willing to sign the NDA before receiving detailed system specifications.

How to Apply

To be considered, please include:

A brief summary of your relevant experience with:

PLC + VFD systems

HVAC or compressor-based applications

Solar or battery-integrated power systems

Specific examples of similar projects you have completed
(descriptions are acceptable if documentation cannot be shared)

Your availability and estimated turnaround time

Generic proposals will be ignored.
We are looking for a senior-level engineer who can design this system correctly the first time.