Exploration of Multilevel Current Source Converters

电力电子转换是能量转换系统的核心要素，起着不同形式电能之间的接口作用，是实现低碳经济的一项使能技术。到2030年，预计高达80%的电力将在发电和消费之间的能源供应链中使用电力电子。多电平变流器是电力电子变流器的一种，与已有的两电平变流器相比具有很大的优势。这些特性包括减少谐波失真、降低电压/电流应力(dV/dt、di/dt)和减轻电磁干扰(EMI)。多电平变流器可分为多电平电压型变流器(MVSC)和多电平电流型变流器(MCSC)。MCSC表现出几个独特的优势特性，这些特性可能有利于其在飞机、混合动力/电动汽车和微型可再生能源发电中使用的低压变流器中采用。例如，在MVSC中，电感被用作主要的储能元件，它比电容更可靠。MCSC具有固有的限流能力，可用于限制故障电流，并为设备过流保护留出更多时间。它可以防止其他部件的进一步损坏或故障，并避免因过电流而起火。对MCSCs的研究还处于初级阶段。因此，该项目将从变流器拓扑推导、调制技术、电感电流平衡、损耗和效率评估等方面对MCSC进行探索。这些挑战的成功研究将揭示MCSC的好处，促进变流器的广泛应用。研究将通过建模、控制、仿真和实验验证来进行。功率变流器拓扑的研究对于电力电子系统的研究具有重要意义。MCSC的突破将使英国世界领先的航空航天行业和可再生能源原始设备制造商受益。MCSC的成功开发还将为元件或子系统供应链、开发新的功率半导体技术(反向阻挡IGBT、宽带隙器件)以及需要新的电源模块配置和新的缠绕元件提供支持。

Power electronic conversion is a central element of energy conversion systems, acting as the interface between different forms of electrical energy and is an enabling technology for low-carbon economy. By 2030, it is expected that as much as 80% of all electric power will use Power Electronics somewhere within the energy supply chain between generation and consumption. Multilevel converter is one type of power electronics converter and can offer substantial benefits over the established two-level converter counterparts. These include reduced harmonic distortion, less voltage/current stress (dv/dt, di/dt), and mitigated electro-magnetic interference (EMI). Multilevel converters can be classified into multilevel voltage source converters (MVSCs) and multilevel current source converters (MCSCs). The MCSC exhibits several unique advantageous characteristics that may favour its adoption in the low voltage converters used in aircraft, hybrid/electric vehicles and micro renewable power generation. For example, inductors are used as the main energy storage elements in MCSCs, which are more reliable than capacitors in MVSCs. The MCSC has intrinsic current limiting capability, which can be used to constrain fault currents as well as leaving more time for device over-current protection. It may prevent further damage or failure of other components and avoid fire due to over-current. The research into MCSCs is at its infancy. The project therefore will explore the MCSCs through converter topology derivation, modulation techniques, inductor current balancing, loss and efficiency evaluation, etc. The successful investigations of these challenges will reveal the benefits of the MCSCs and facilitate the wide application of the converter. The research will be carried out through modelling, control, simulation and experimental verification. The study of power converter topologies is valued as enabling research in power electronic systems. A breakthrough in MCSCs will benefit the UK world-leading aerospace industry and renewable energy OEMs. Successful development of MCSCs will also feed into the component or sub-system supply chain, in exploiting new power semiconductor technologies (reverse blocking IGBT, wide-bandgap devices) and in requiring new power module configurations and new wound components.