通常情况下，电源设备的内阻抗可以起到缓冲变频器直流滤波电容的无功功率的作用。这种内阻抗就是变压器的短路阻抗。电源容量相对变频器容量越小，内阻抗值相对越大，谐波含量越小；电源容量相对变频器容量越大，则内阻抗值相对越小，谐波含量越大。所以选择变频器供电电源变压器时，*选择短路阻抗大的变压器。
National Instruments GPIB-1014 VME Board 180155-01 SGI
National Instruments PXI-6031E 64-Ch Multifunction DAQ
National Instruments SCXI-1302 50-Pin Terminal Block
NATIONAL INSTRUMENTS SCXI-2000 MAINFRAME
National Instruments TB-2605 Terminal Block PXI
Set of National Instruments GPIB 488.2 User Manuals
Sealed National Instruments HIQ for Macintosh/Power Mac
NEW NATIONAL INSTRUMENTS 777080-01 ELECTRO RELAY 8 SPDT
National Instruments CB-100 I/O Connector Block Kit
NATIONAL INSTRUMENTS PCI-6033E I/O BOARD DAQ
