Effects of excitation signal on electrical resistance of Populus davidiana wood
Bao Zheny · China Forestry Science and Technology · 2015
The test of wood electrical resistance is important for moisture content and decay detection. Different current types,voltages,waveforms and frequencies of excitation signal were applied to investigate the effects of excitation signal on electrical resistance of Populus davidiana. The results were analyzed by ANOVA and regression analysis,which showed that the effect of current type on wood electrical resistance was significant,the direct current(DC) resistance of wood was higher than that of the alternative current(AC) resistance. The voltage of DC signal affected the wood electrical resistance,which decreased with the increasing of voltage. Except the frequency,neither voltage nor waveform of AC signal significantly affected the resistance. The resistance decreased with the increasing of AC frequency. It was concluded that AC signal around 1 000 Hz was a suitable excitation signal for the test of wood electrical resistance.