基于Labview的非NI采集设备频率测量法

Based on the Labview Non NI Acquisition Device Frequency Measurement

针对测试系统中使用非美国国家仪器公司(NI)生产的采集设备,因为其底层硬件系统与Labview兼容性较差,造成测量信号的频率等时间值不准确的情况。提出两种解决办法,过零点测试法和VI数据处理法,其中过零点检测是基于差值定理通过寻找零点来测量频率,VI数据处理法是通过对VI模块的研究来实现其测量频率的目的。不仅在Labview平台上实现了这两种方法,而且利用某公司生产的型号为USB7660BN的采集卡加以验证,分别对频率为1 KHz,3 KHz,5 KHz,6 KHz的信号进行测量。测量结果表明,这两种方法所测误差均在1 Hz以内,全部能够完成测试要求。

For the use of non National Instruments （NI） acquisition equipment in the test system, poor compatibility of its underlying hardware system and Labview causes measuring frequency and time value was not accurate. Two solutions are proposed including zero crossing test method and VI data processing method, and using zero crossing test method to measure the frequency was based on the Error Theorem by finding zero ,VI data processing method achieves the aim to measure the frequency by the research on VI model . Not only these two methods are implemented in the Labview platform, but also are confirmed for USB7660BN acquisition equipment by measure signals whose frequency is IKHz, 3KHz, 5KHz, 6KHz respectively. Results show that two methods measured the error of less than 1Hz and could complete all testing requirements.