Hardware & Software Development of DC-to-DC Convertor for Solar Battery Charger for Electric Vehicles

Customer Profile:

A USA based Tier-I Automotive Supplier, our customer is a reputed brand name for power, sensors, charging and data connectivity products.

Business Challenge:

Our customer has conceptualized a Solar based battery charging product for Electric Vehicles. This product is a PoC to address end-user pain point of each time searching for a charging point/station for their Electric Vehicles.

With plans to initially launch this Photovoltaic (PV) battery charger for European market, our customer was on a look-out for an embedded product engineering services company. They wanted to partner with a services company that has automotive domain knowledge and embedded software and hardware development expertise

Embitel Solution:

After initial consulting workshops, the customer developed trust in the capabilities of our Automotive Product Development teams.

Our experience in Solar energy based products and more than 11 years of domain expertise in automotive ensured that this was a value-add partnership for our customer.
 

• We partnered with the customer for software and hardware development of PV DC-to-Dc convertor to charge both 48 V and 12 V batteries in an electric vehicle
• Hardware development using V-Shaped HDLC model:
  • HRS, Schematic Preparation and Analysis, Layout, E-BOM procurement, Fabrication, assembly, board bring up and Functional Testing
  • This automotive grade design was tested & verified using EM Analysis , Thermal Analysis, Signal Integrity and Power Integrity tests
  • Hardware design also included Reverse Polarity Protection and Isolation
• Design and development of Design two-stage MOSFET based H-Bridge converter. This two stage dc-dc conversion helped to achieve higher efficiency and support up to 200 W power transfer
• Layered software architecture developed using V-Shaped SDLC model:
  • MPPT (Max Power Point Transfer) based software code was designed to achieve 97-98% efficiency (converting 16 V solar power to output of 12 V or 48 V)
  • Designed and developed a software with intelligence to avoid draining of batteries. This is ensured by cutting off the supply when upper or lower power thresholds were crossed
  • LIN based communication interface to select output of either 12 V or 48 V based on the application

Embitel Impact:

• DC-to-DC convertors are generally bulky devices. However, our embedded hardware development team was able to achieve a challenging target of optimizing the form factor to less than 10 mm (including boxing)
• Such sophisticated automotive hardware design ensured cost savings for our customer
• This is also an one of its kind Solar Based Automotive product with dual power outputs to serve the various applications of electric vehicles:
  • 12 V output for Head lights, HVAC, Indicators, Music Systems and similar applications
  • 48 V output for braking systems, power steering, turbochargers, emission control, ant-lock brake systems and similar applications

Tools and Technologies:

• Texas Instrument C2000 Piccolo 32-bit Microcontroller
• Code Composer Studio
• ORCAD for Schematic Design
• Allegro for  Layout
• Hyperlynx 8.0 : EM and Thermal Analysis
• Simulation: TI WebBench, Matlab, LTSpice