摘要 |
The invention presents a structure for the conversion of direct current electric power into alternating current electric power, characterised in that it is simple, highly efficient and minimises the problem of electromagnetic compatibility. The circuit includes, in its first preferred embodiment, six switching elements governed by a command unit, four switches forming an H-bridge (T1, T2, T3, T4) and two auxiliary switches (T5D, T6D), and two auxiliary diodes (Daux1 and Daux2). The elements of the H-bridge switch at grid frequency, whereas T5D and T6D switch at high frequency by means of pulse width modulation (PWM), or other appropriate modulation techniques. The voltage of these auxiliary switching elements (T5D, T6D) is limited topologically to half the direct current input voltage (Vin), thereby reducing switching losses and resulting in a high performance converter. |