Abstract: For welding of the straight weld pipe,most commonly-used power source type is the electronic tube power supply featuring such disadvantages as high energy consumption,high voltage and short service life of the electronic tube. Along with development of electric power-service electronic technology,solid high frequency(HF) power sources have been developed both at home and abroad. A new type solid HF power supply for steel tube-welding has been developed by Baoding Hongxing High Frequency Equipment Co.,Ltd. Described in the paper are the performances and features of the said power supply,and the analysis of the switching loss of the electric power-service components under high frequency condition. The difference between the output ripple waves of the electronic power source and the above mentioned solid power supply is identified by comparing the wave forms of the two.