A driving pulse edge modulation technique and its complex programming logic devices implementation

With the continual increase in switching speed and rating of power semiconductors, the switching voltage spike becomes a serious problem. This paper describes a new technique of driving pulse edge modulation for insulated gate bipolar transistors(IGBTs). By modulating the density and width of the pulse trains, without regulating the hardware circuit, the slope of the gate driving voltage is controlled to change the switching speed. This technique is used in the driving circuit based on complex programmable logic devices(CPLDs), and the switching voltage spike of IGBTs can be restrained through software, which is easier and more flexible to adjust. Experimental results demonstrate the effectiveness and practicability of the proposed method.

Electromagnetic Compatibility Analysis of High-Power Pulse Drive Source

Due to the widespread application in recent years, high-power pulse sources have received special attention from large companies and R & D institutions around the world. Compared with foreign mid-range and high-end products, China’s development in this field is relatively lagging behind and lacks mature mid-range and high-end products. The reason is not only because of lack of theoretical support, but more importantly, in the pursuit of indicators and design, the electromagnetic compatibility of the equipment has not been studied thoroughly, resulting in a large degree of distortion in the output waveform, resulting in a reduction in actual value. This paper introduces the sources of high-power pulsed electromagnetic interference of the main driving source, conducts a reasonable high-power electromagnetic compatibility driving source dynamic analysis, and proposes measures to improve electromagnetic compatibility.

A novel 300 kW arc plasma inverter system based on hierarchical controlled building block structure

To date, the high power arc plasma technology is widely used. A next generation high power arc plasma system based on building block structure is presented. The whole arc plasma inverter system is composed of 12 paralleled units to increase the system output capability. The hierarchical control system is adopted to improve the reliability and flexibility of the high power arc plasma inverter. To ensure the reliable turn on and off of the IGBT module in each building block unit, a special pulse drive circuit is designed by using pulse transformer. The experimental result indicates that the high power arc plasma inverter system can transfer 300 kW arc plasma energy reliably with high efficiency.

Synchronization of Digital Chaos in Secure Communication Systems

The theories of synchronization based on secure communications using digital chaos are presented. A new synchronous method-cycles-interval Pulse drive is developed and realized. Experimental results show it is available, and in order to reduce synchronous noise, a method using model references solves the ratio of signal power to noise power, so the secure communication system can be realized.

Dynamics of cavity soliton driven by chirped optical pulses in Kerr resonators

Recent researches have demonstrated that pulsed driving is an effective method to increase the temporal overlap between cavity soliton(CS)and pump field,thereby increasing the pump-to-comb conversion efficiency.The amplitude-modulated inhomogeneity of the background wave causes the solitons to drift toward edges of the driving pulse.To eliminate the mul-tiple temporal trapping positions,induced by the spontaneous symmetry breaking,we propose the chirped pulse driving for deterministic single soliton generation.We theoretically explain the physical mechanism of the chirp pulse driving,as the combination of amplitude and phase modulation.Our numerical simulations demonstrate the chirp is responsible for the single soliton generation.A detailed investigation for dynamics of CSs sustained by chirped pulses,shows the recovery of spontaneous symmetry breaking.In addition,the desynchronized chirped pulse driving is also considered here.Considering a weak chirp parameter,the desynchronization-dependent trapping position diagram is divided into multiple areas including two CSs,a single CS,two oscillating CSs,and no CS.With a sufficient chirp parameter considered,the trapping position curve becomes a monotonous function of the desynchronized drift velocity,which indicates deterministic single soliton generation.