Research On Digitalized High Power Integrated Power Electronics Modules With High Reliability

With the development and maturity of the power electronic technology in high power applications, there is a higher demand for reliable high power universal power semiconductor module unit. At present, insulated gate bipolar translators (IGBTs) are widely used in medium-and low-voltage high power electronic equipment. This dissertation was focused on some key technologies on reliable digitalized high power integrated power electronic modules based on multi-IGBT paralleling.Based on some basic characteristic of IGBT, drive and protection technologies for high power modules using IGBT paralleling technology were classified and compared. And then, aiming at achieving dynamic and steady state current sharing and over voltage and short current protection, digitalized drive and protection strategies for paralleled IGBTs were designed. Turn off peak voltage is usually very high which may threatens safe operation of semiconductor devices. A turn off peak voltage suppression technology on the basis of digital control was proposed after analyzing the causes of the problem. Experimental results verified the validity of the designing method and the peak voltage suppression technology.In traditional converter applications, signal conductor quantities increases basically proportionally to that of power modules, which not only brings more difficulties in assembling, but also reduces the reliability of the whole system. Therefore, ring network communication strategy was introduced. Main circuit topology suitable for high speed ring network communication with single fiber loop was designed. Then the communication protocol was developed. Moreover, its normal communication mode and fault handling strategy are provided. Considering time delay introduced by this communication method, a time delay correction approach through software implementation was given to guarantee that the time delays of all nodes in the loop were same with each other. Through above all sorts of means, a high speed ring network communication strategy with high reliability and large potential application value were established. Experimental results shows its feasibility and practicability.Reliable service has the direct bearing on that high power converter equipment can be successfully applied in high power occasions and reliability is research key point and difficulty in industry for a long time. This dissertation analyzed the Electro Magnetic Compatibility (EMC) of the converter modules in power electronic equipment. The interfering sources, conducted paths and the incidences of both common and differential mode interferences were studied. And then interference rejection technologies were discussed in order to effectively suppress the interferences and improve the reliability with small cost. Simulation and experiment results verified the correctness of the analysis. Successfully resolving interfering problem in engineering practice declared the validity of the suppression technologies.Finally, power electronic building block (PEBB) with high power was developed and applied in high power electronic equipment. With a long time full power operation, its reliability was guaranteed. For higher power applications, converter paralleling is a common choice. On the basis of the parallel system model, this dissertation studied on the output current consistency and its relative factors. Methods for increasing the consistency and reducing circular current were further obtained. Experimental results verified the rationality of the power module design and the effectiveness of output current consistency enhance means.