Date of Award


Document Type

Campus Access Dissertation


Electrical Engineering

First Advisor

Antonello Monti


Virtual prototyping is the act of configuring and using a software-based model of a product, system, or components to explore, test, demonstrate and validate its design and design alternatives. Virtual prototyping is increasingly used to develop and test new products. It minimizes the failure risk and shortens product evolution cycles. HIL (Hardware in the Loop) is one of the most widely used methods for virtual prototyping. But this technology is limited to signal coupling and it is based on proprietary solutions or dedicated hardware. A novel technology, Power Hardware in the Loop (PHIL), extends the capability and improves the methodology of HIL by allowing natural coupling between the connections of the simulation and the hardware. The key elements of the PHIL technology is the simulation/hardware interface. A very high-bandwidth is required by the simulation/hardware interface in order to minimize problems related to the stability of a hybrid system. The main problem is that very high speed switches are usually not available for the power converter which is the core component of the simulation/hardware interface; consequently it is difficult to achieve wide bandwidth for the whole power interface. This dissertation describes a suitable high-speed power switch for the PHIL application.

The rapidly developing research on wide-band III-Nitride semiconductor materials (such as GaN) has been driven by the unique properties of these materials, such as high electron mobility, high saturation velocity, high sheet-carrier concentration at hetero-junction interfaces, high breakdown voltages, etc. These properties make the use of III-Nitride technology a promising approach for high-power, high-temperature and high-speed applications in power electronics, and make GaN power devices a very good choice for the wide-bandwidth power converter application in PHIL technology.

Unfortunately, the use of wide-band III-Nitride (GaN) devices is currently limited mainly to telecom and low-power applications. The lack of high-frequency drivers is one of the factors preventing their application to power converters. In order to make GaN devices applicable in power electronics and best exploit the capabilities and advantages of these devices, this dissertation presents a design for a new wide bandwidth GaN based Power Electronic Building Block (PEBB). The key point of this activity is the design of a gate drive circuit for GaN power HFET devices. This dissertation introduces the design of a high-speed, highly-efficient gate drive circuit for GaN power HFETs. After this topology was verified to be feasible, an integrated circuit (IC) for the drive circuit was designed and fabricated. This driver IC facilitates the application of the GaN devices in power electronics, improves the property of the drive circuit, and makes it possible to achieve miniaturization, high efficiency, reliability, and low cost for power systems. This dissertation introduces the design of the driver IC, and the experimental results verify the feasibility of GaN HFET as a high speed power switch in power electronics.

This dissertation also introduces the design of a high speed power converter (an H-bridge) which is composed of the new driver ICs and GaN power HFETs. The design of the H-bridge make a wide bandwidth power converter available for the simulation/hardware interface in PHIL and hence provides frequency-agile wide-bandwidth power interface to support incremental virtual prototyping. An example of this high-speed H-Bridge in DC/AC power inverter application is presented in this dissertation, which further verifies the feasibilities and advantages of this wide bandwidth PEBB.


© 2009, Bo Wang