Self-Powered Synchronized Switching Interface Circuit for Piezoelectric Footstep Energy Harvesting

Abstract

Piezoelectric Vibration converters are nowadays gaining importance for supplying low-powered sensor nodes and wearable electronic devices. Energy management interfaces are thereby needed to ensure voltage compatibility between the harvester element and the electric load. To improve power extraction ability, resonant interfaces such as Parallel Synchronized Switch Harvesting on Inductor (P-SSHI) have been proposed. The main challenges for designing this type of energy management circuits are to realise self-powered solutions and increase the energy efficiency and adaptability of the interface for low-power operation modes corresponding to low frequencies and irregular vibration mechanical energy sources. In this work, a novel Self-Powered (SP P-SSHI) energy management circuit is proposed which is able to harvest energy from piezoelectric converters at low frequencies and irregular chock like footstep input excitations. It has a good power extraction ability and is adaptable for different storage capacitors and loads. As a proof of concept, a piezoelectric shoe insole with six integrated parallel piezoelectric sensors (PEts) was designed and implemented to validate the performance of the energy management interface circuit. Under a vibration excitation of 1 Hz corresponding to a (moderate walking speed), the maximum reached efficiency and power of the proposed interface is 83.02% and 3.6 mW respectively for the designed insole, a 10 kΩ resistive load and a 10 μF storage capacitor. The enhanced SP-PSSHI circuit was validated to charge a 10 μF capacitor to 6 V in 3.94 s and a 1 mF capacitor to 3.2 V in 27.64 s. The proposed energy management interface has a cold start-up ability and was also validated to charge a (65 mAh, 3.1 V) maganese dioxide coin cell Lithium battery (ML 2032), demonstrating the ability of the proposed wearable piezoelectric energy harvesting system to provide an autonomous power supply for wearable wireless sensors.

A High-Reliability Piezoelectric Tile Transducer for Converting Bridge Vibration to Electrical Energy for Smart Transportation

“…Two components were connected in parallel; meanwhile, in each component, a pair of sensors was connected in series. Here, we have not utilized many sensors due to the problems of parasitic capacitance and device–device capacitance occurring during the device’s operation, which cause low responsivity [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ]. A rectifier circuit using a four-diode bridge device (MB6S, Fairchild, WI, USA) was attached to convert AC values to DC values.…”

“…Among them, mechanical energy harvesting based on the piezoelectric effect is an important method since electrical energy can be directly obtained from transportation operations. Using the vibrational forces from cars moving on a bridge or road or by harnessing human footsteps on the street, a piezoelectric transducer produces an electric charge, which can provide a power source for traffic control, structural health monitoring, internet-of-things devices, electric vehicles, or lighting on the street [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 ].…”

“…Lead zirconate titanate (PZT) nanofibers are widely used in the active layer because they exhibit a strong piezoelectric response and mechanical flexibility [ 2 ], which are conducive to the creation of a high-performance device. So far, most studies on piezoelectric harvesting transducers using PZT nanofibers for transportation have focused on enhancing power levels [ 5 , 6 , 7 , 8 , 9 , 10 ]. Reliability is an important factor of an electronic system that must be investigated.…”

“…Reliability is an important factor of an electronic system that must be investigated. Recently, several groups have mentioned this factor [ 5 , 6 , 7 , 10 ]. For example, Ammar et al [ 5 ] used a piezoelectric sensor composed of PZT in an energy-harvesting shoe.…”

A compact self-powered inductor-less piezoelectric energy harvesting circuit using gyrator

“…In our present digital economy, the exponential growth of information technology such as intelligent sensing, wearable electronic devices [1], Micro Electromechanical Systems, Internet of vehicles, and Internet of Things (IoT) [2] have been extensively used in transportation, smart city, and modern biomedicine, etc. Nevertheless, the issue of power supply to mobile or static wireless sensor nodes (WSNs), as a core of hardware is inadequate by space or time scale.…”