Description

Self-power techniques and ultra-low power consumption are two vital keys in wearable applications as well as stand-alone applications because of the size constraints for batteries. To slove the problem, energy extraction technique from the ambient temperature is one of the best solutions. So, we propose a highly efficient energy converter to harvest thermoelectric energy. To absorb thermoelectric energy, the proposed circuit uses maximum power point tracking (MPPT) and zero-current switching (ZCS) based on digital counters. The proposed technique is able to adapt to a wide range of temperature differences. The integrated ZCS module plays an essential role in reducing the loss induced by inaccurately controlling the high-side switch. Besides, the maximum power extracted from the thermal energy source is monitored with the MPPT module.  The circuit proposed consists of 3 blocks: DC-DC booster starter circuit, fully digital controller and the most important block – DC-DC booster main circuit.

Target

• Harvesting thermoelectric energy from a wide range of temperature differences between human and ambient environments.
• DC-DC boosting from thermoelectric voltage source up to 4.2V at output to charge & store energy in batteries or capacitors.
• High efficiency DC-DC converting and reducing energy losses.

Block Diagram

Schematics

The schematic of the proposed thermoelectric energy

The block diagram of the counter-based MPPT controller

The block diagram of the counter-based ZCS controller

Team Members

To Vu Thanh Nhan, Tong Ngoc Quyen: Student at Computer Engineering Technology, Faculty of Electrical and Electronics Engineering, HCMC University of Technology and Education, Vietnam.

Knowledge

Computer architecture and organization, Digital, Integrated system and microchip design, VLSI Integrated Circuit Design, Analog Circuit Design.