电流环软启动通过输出电流指令递增实现，电压环软启动则比较了直流侧电压指令逐步升高法、恒定电流充电法、变PI参数调节法三种策略。
Three soft start-up technique for voltage loop are compared with each other, which are the reference of DC bus voltage gradually increasing, constant charging current and different PI modulation.
“可调节参数的修正迭代法”求解非线性代数方程组。
The value of linear solutions is treated as initial value of the nonlinear solutions for iteration.
稳定化双共轭梯度法用于求解稀疏线性方程组，可调节参数的修正迭代法用于求解非线性代数方程组。
Linear equations of sparse matrix are solved by Biconjugate Gradients Stabilized Method and nonlinear algebraic equations are solved by parameter-regulated iterative procedures.
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