The Effect of Switch Triggering Offset and Switch on-time Duration on Harvested Power in Synchronized Switch Harvesting on Inductor

Through SPICE simulation, different piezoelectric harvester interface circuits are demonstrated and compared. In synchronized switch harvesting on inductor interface, the inductor’s quality factors are very important on calculating the harvested power so that the power from SSHIs depending on the inductor’s Q is calculated. Especially, parallel SSHI shows the optimal output voltage to harvest the maximum power varies according to the Q severely. Switch triggering offset and switch on time duration are very interest in calculating the power in SSHI. So, the simulations of the effect of these factors on SSHI’s power are performed. It is conformed that switch triggering offset has more impact on the s-SSHI than p-SSHI. The switch on-time duration is more important in case of the p-SSHI. p-SSHI shows when the on-time duration becomes more than 1.3 times or less than 0.7 times of exact duration time, the harvested power gets zero. s-SSHI reveals the characteristics that when less than 1.5 times exact on-time duration, the harvested power varies significantly with the on-time duration, however larger than 1.5 times exact on-time duration has scarcely influenced on the harvested power.