Hybrid converter and wind power generating system

A wind power generating system, comprising a common AC bus (14), a first step-up transformer (18), a second step-up transformer (20), a third transformer (12), a fourth transformer (13), a hybrid converter (1), and an AC filter (15), and a reactive power compensator (16) respectively connected to said common AC bus (14);

• wherein an input port of said first AC transformer (18) is connected to a wind turbine generator set (17), an output port of said first step-up transformer (18) is connected to an input port of said second step-up transformer (20) via an AC transmission line (19), and an output port of said second step-up transformer (20) is connected to said common AC bus (14) via said AC transmission line (21);
• wherein
• said hybrid converter (1) comprises a voltage source converter (2), a first line commutated converter (3a), and a second line commutated converter (3b);
• a positive DC terminal of said voltage source converter (2) is connected to a negative DC terminal of said first line commutated converter (3a), a positive DC terminal of said first line commutated converter is connected to a positive DC transmission line (8) via a first inductor (10), a negative DC terminal of said voltage source converter (2) is connected to a positive DC terminal of said second line commutated converter (3b), and a negative DC terminal of said second line commutated converter (3b) is connected to a negative DC transmission line (9) via a second inductor (11);
• and
• an AC terminal of said second voltage source converter (2) is connected to said common AC bus (14) via said fourth transformer (13), and an AC terminal of said first line commutated converter (3a) and an AC terminal of said second line commutated converter (3b) are respectively connected to said common AC bus (14) via said third transformer (12).