Method and device for a state-dependent control of the transient behavior of semiconductor power switches

摘要

The invention relates to a comprehensive control method for switch on and off processes of power semiconductor switches (S₁–S₄). In a switching phase A the collector current transient di_c/dt is controlled in order to safeguard a controlled clear-off of the edge zones of a serial freewheeling diode (D_s). In a switching phase B the collector voltage gradient dv_CE/dt is controlled in order to specifically switch the power semiconductor switch (S₁–S₄), thereby establishing a closed control loop by returning primary and optionally secondary condition variables (v_c, dv_c/dt, i_c, di_c/dt, i_G, v_G, di_G/dt, dv_G/dt) of the power semiconductor switch (S₁–S₄). The embodiments relate inter alia to prephases A0, B0 for achieving the controllability of the power semiconductor switch (S₁–S₄), a v_CE control by defining a collector voltage set-point function v_CE^ref (t), detection of a transfer time (t₁, t₂) of switching phases A and B, a variable controller amplification (k_p(t)), an upper and lower limit (S_M, S_m) in accordance with an ideal gate current gradient (i_G(t)) and a tolerance band control for the collector voltage (v_CE). The invention further relates to a gate driver (GT), preferably with partitioned amplifier stages (7a, 7b) for carrying out the inventive method, and to a power semiconductor switch (S₁–S₄) and a series connection of power semiconductor switches (S₁–S₄) that are provided with such a gate driver (GT).