Through the analysis of three phase prepayment control box use condition in Xiangfan district, the problems which are possible appearing during its operating process were pointed out.
Under the proper simplified condition, the calculation formulas of rectification voltage and phase current were deduced out respectively and were testified by experiment.
在适当的简化条件下，推导出各自整流电压和相电流的计算公式，并通过了试验验证。
3
If we introduce the ladder-shaped circuit simple in good time, the oscillating frequency and oscillating conditionof rc phase shift oscillating can be worked out easily.