Highly integrated GaN power converter to calm the interference

在支持人们生活条件、运动和通信的各种系统中，我们需要电力电子转换器来传输电能。例如，它们可以将太阳能电池板产生的几乎恒定的电压和电流传输到电网，在电网中电压和电流是交替的极性。它们还可以从家用电源插座传输交流电压，为电动汽车、智能手机和笔记本电脑充电，这些地方的电池电压几乎是恒定的。由于电力来自多种能源（化石燃料和可再生能源），电力电子转换器的效率对减少二氧化碳排放，实现净零排放和可持续发展起着至关重要的作用。电力电子变换器的工作依赖于半导体晶体管。电力电子转换器通常有6个或更多的晶体管。每个晶体管都像一个“开关”一样工作，按照一定的控制模式反复打开和关闭。当晶体管从一种状态切换到另一种状态时，电压和电流会在其上重叠，从而导致功率损失。如果电力电子变换器的效率需要提高，每个晶体管的转换应该减少。最近开发的一种基于新型氮化镓（GaN）材料的晶体管证明了在纳秒内传输千瓦功率的能力，与传统的硅晶体管相比，这将功率损耗降低了10倍以上。然而，快速功率转换带来了电磁噪声的挑战，电磁噪声将从一个晶体管传播到另一个晶体管，并从高功率电路传播到低功率控制电路以产生控制模式。因此，晶体管将承受降低其寿命的更高电压和电流尖峰，低功率电路将产生错误的控制模式并使整个转换器无法运行。在GaN的快速开关下，噪声干扰也达到了基于硅晶体管的传统方法无法工作的程度。该提案的一个雄心勃勃的目标是通过使用一种新的设计将多个GaN晶体管与其控制电路连接起来，并将它们组装在一个功率转换器中，从而减少噪声干扰。我们将首先识别每个晶体管产生的噪声干扰强度和极性，然后使用相同强度但不同极性的噪声干扰相互抵消。因此，在我们提出的设计中，总有效噪声干扰将减少到几乎为零，并且可以大大提高功率转换器的效率。为了实现这一雄心勃勃的设计，将通过知识转移和学习与法国安培实验室建立新的合作伙伴关系。法国安培实验室在3D高密度封装方面的独特和全球领先的专业知识对于设计的实施至关重要，它将补充诺丁汉大学团队在功率晶体管应用方面的专业知识。最终，它将使英国受益，并使英国在新兴的氮化镓电力电子技术方面处于世界领先地位，这将巩固净零和可持续发展。

In various systems that underpin people's living condition, movement and communication, we need power electronics converters to transfer electrical energy. For example, they can transfer almost constant voltage and current generated from a solar panel to the power grid, where the voltage and current are alternating polarities. They can also transfer alternating voltage from household power sockets to charge electric vehicles, smart phones and laptops, where the voltage of the batteries is almost constant. As the electricity is generated from a combination of sources (fossil fuel and renewable energy), the efficiency of the power electronics converters plays a vital role to reduce CO2 emission for Net Zero and sustainable development. The operation of the power electronics converters relies on the semiconductor transistors. A power electronics converter usually has 6 or more transistors. Each transistor works like a "switch" to turn on and off repeatedly following certain control patterns. When a transistor switches from one state to another, there is an overlap of voltage and current across it which causes power losses. If the efficiency of power electronics converters needs to be improved, each transistor's transition should be reduced. A recently developed transistor based on emerging gallium nitride (GaN) materials demonstrate the capability to transfer the kilowatt power during nanoseconds, which reduces the power losses more than 10 times in comparison to a traditional transistor based on silicon. However, the fast power transition comes with the challenge of the electromagnetic noise, which will propagate from one transistor to another, and from a high power circuit to a low power control circuit for control patterns generation. Consequently, the transistor will withstand higher voltage and current spikes that reduce their lifetime, and the low power circuit will generate wrong control patterns and make the whole converter fail to operate. Under the fast switching of GaN, the noise interference also reaches to a level that conventional approaches based on silicon transistors can no longer work. An ambitious target of the proposal is to reduce the noise interference by using a new design to connect multiple GaN transistors with their control circuits, and assemble them together in a power converter. We will first identify noise interference strength and polarity generated by each transistor, and then use the noise interference of the same strength but different polarities to cancel each other. Therefore, the total effective noise interference will reduce to almost zero in our proposed design, and power converter efficiency could be greatly improved. To achieve this ambitious design, a new partnership with French Ampere Lab will be developed and built via knowledge transfer and learning. The unique and global leading expertise of French Ampere Lab on 3D high-density packaging is crucial for the implementation of the design, and it will complement University of Nottingham team's expertise of power transistor application. Eventually, it will benefit UK and make UK a world leading role for emerging GaN power electronics technology that will underpin Net Zero and sustainable development.