Theoretical and Experimental Study of Nonlinear and Electro-Magneto-Mechanical-Based Piezoelectric Vibration Energy Harvester

Figure 8

Voltage in time history and the phase portrait for the linear EMM system: (a) voltage-time@23 Hz; (b) phase portrait@23 Hz; (c) voltage-time@28 Hz; (d) phase portrait@28 Hz; (e) voltage-time@33 Hz; (f) phase portrait@33 Hz.

(a)

(b)

(c)

(d)

(e)

(f)