A constant switching frequency with the sixth-order harmonic injection PWM concept is established, and a sixth-order harmonic injection technique is developed for the harmonic reduction of a single-switch three-phase boost rectifier. The approach employs a constant duty cycle with sixth-order harmonic injection to suppress the dominant (fifth-order) harmonic in the input currents. Hence, to meet the THD<10% requirement, the rectifier voltage gain can be designed down to 1.45; to meet the IEC 1000-3-2 (A) standard, the output power can be pushed up to 10 kW for the application with a 3X220 V input and a 800 V output. The results are verified on a 6-kW prototype. The injection principle is graphically explained in current waveforms and mathematically proved. Two injection methods are proposed to meet either the THD requirement or the IEC standard. The injection implementation and design guidelines are provided. The boost inductor design and EMI filter design are discussed. An average small- signal model based on the equivalent multi-module model is developed and experimentally verified. The variations of the small-signal model against load are demonstrated, and the compensator design is discussed. The results show that at no load, the dominant pole of the control-to-output transfer function approaches the origin and causes more phase delay, making the control design difficult. To avoid the no load case and to simplify the control design, a 50-W dummy load (1% of the full load) is added. Finally, a simple nonlinear gain control circuit is presented to mitigate the load effect and reduce the dummy load to 10 W. / Master of Science

Near-field wireless power transfer (WPT) technology facilitates the energy autonomy of heterogeneous systems, significantly augmenting complementary metal-oxide-semiconductor field-effect-transistor (CMOS) technology. In low-power wearable devices, existing power conditioning integrated circuits do not maximize the power factor (PF) for rectification and power conversion efficiency (PCE) due to multiple conversion. Additionally, there is no core power management for the entire power flow. The majority of the research focuses on active rectifiers, which reduce the turn-on voltage for rectification. Certain studies target the output voltage regulation via feedback to the transmitter or direct battery charging without power maximization. Firstly, this study investigates a high-power factor WPT front-end circuit that is namely the mono-periodic switching rectifier (MPSR) and implemented in a 0.18µm 1.8V/5V CMOS process. Integrated phase synchronizers are used to align the waveshape of a wirelessly-coupled sinusoidal voltage source in a receiving coil to the corresponding conducting current. Using this approach, the PF can be increased from roughly 0.6 to unity without requiring any wireless or wired feedback to the transmitter. The proposed MPSR can also provide AC-DC rectification, and step up and down the sinusoidal voltage source's peak amplitude using a pulse-width modulator. Measured voltage conversion ratios range between 0.73X and 2X, and the PF can be boosted up to unity. Secondly, the wireless power system-on-chip (WPower-SoC) is proposed and implemented in a 0.18µm 1.8V/3.3V CMOS process. The WPower-SoC integrating power management can provide rectification, output voltage regulation, and battery charging. Additionally, the implementation of feedforward envelope detection (FED) can reduce the variation in a wireless power link and improve load transient responses. Simulated results demonstrate that 5% of the output voltage regulation is improved when an output load changes. Moreover, the FED reduces approximately 40% of the transient response time. Overshoot and undershoot voltages are decreased by 23% and 26.5%, respectively. The measured output voltage regulates at 3.42V and can supply output power up to 342mW. A temperature sensor as part of the power management core remains active when the WPT receivers enter sleep mode to prolong the battery usage time. In the final part of this study, a nano-watt high-accuracy temperature sensing core is implemented in a 0.18µm 1.8V/3.3V CMOS process that can self-compensate the temperature shift without the need for additional compensating techniques that consume extra power.