激励信号对山杨木材电阻测量的影响

木材电阻测量在含水率检测和立木腐朽检测等方面具有重要意义。为分析激励信号对木材电阻测量的影响,以含水山杨试件为研究对象,在实验室使用不同电流种类、电压、波形和频率的激励信号进行电阻测量试验,并对电阻测量值进行方差分析和回归处理。结果表明,电流种类对木材电阻测量有显著影响,木材的直流电阻比交流电阻高。直流信号的电压对电阻有影响,电阻随直流电压升高而减小。交流信号的电压和波形对木材电阻的影响都不显著,但频率的影响则是显著的,木材电阻随频率升高而下降。在实验室条件下,1 000 Hz左右的交流信号比较适合作为木材电阻测量的激励信号。
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