Advances in FPGA Based PWM Generation for Power Electronics Applications: Literature Review Amean Al-Safi Electrical and Electronics Engineering Dapartment University of Thi-Qar Thi-Qar, Iraq ameen-sh@utq.edu.iq Ali Al-Khayyat Electrical and Electronics Engineering Department University of Thi-Qar Thi-Qar, Iraq ali-al-khayyat@utq.edu.iq Alyaa Muhsen Manati Electrical and Electronics Engineering Dapartment University of Thi-Qar Thi-Qar, Iraq alyaa-m@utq.edu.iq Liqaa Alhafadhi School of Electrical and Electronic Engineering Universiti Sains Malaysia Penang, Malaysia liqaa.alhafadhi@student.usm.my Abstract—The use of Field Programmable Gate Arrays (FPGAs) for implementing different types of Pulse Width Modulation (PWM) controllers has increased steadily in the last few years. They become dominant tools for implementing different types of PWM due to the flexibility they provide compared to other Digital Signal Processors (DSPs). Different types of PWM have been implemented for single and three phase circuits such as Digital PWM (DPWM), Sinusoidal PWM (SPWM), Space Vector (SVPWM), carrier phase shifted SPWM (CPS-SPWM), Third Harmonic Injection Sinusoidal Pulse Width Modulation (THISPWM) using different FPGA boards. This paper presents a systematic review for the implemented PWM controllers based on FPGA. It describes in detail their types, architectures, and intended application they used for. It also addresses the main contributions, advantages, and disadvantages of different research paper in this area. Current limitations and future development have been drawn based on highlighting the implemented and unimplemented PWM based on FPGA. Keywords—CPS-PWM, DPWM, FPGA, PWM, SPWM, SVPWM, THISPWM I. INTRODUCTION The use of Field Programmable Gate Array (FPGA) as Pulse Width Modulation (PWM) controller in power electronics applications has started in late 1990s. During these years, FPGAs have become a promising technique to solve different challenges that faces hardware engineers. In term of power electronics, [1] illustrated for the first time how to build an FPGA based PWM controller for single phase rectifier with high power factor in 1998. The obtained implementation results confirmed the high displacement power factor and low current distortion. No more studies have been conducted in this research area for almost five years, but the continuous research for a better controlling strategy in term of high switching frequency and low conduction losses as well as the flexibility of the controller’s implementation has drawn the attention of many scholars towards FPGA. That is the main reason that more research papers have started to be published after 2003. In which, [2] built a regular fully digital (symmetric, and asymmetric) sampled three-phase PWM controller using Xilinx FPGA board for three-phase PWM inverter, and [3] used Xilinx XC4005E FPGA to develop a synchronous PWM generator for three-phase flyback converter. Different types of inverters and converters have been controlled based on FPGAs due to the flexibility they provide in comparison with other Digital Signal Processors (DSPs) which clearly described in [4]. Reference[4] provided a comprehensive study between DSP and FPGA based PWM controllers in term of dynamic performance analysis, flexibility, and time to the market. The authors in [5] presented an FPGA-based Digital PWM (DPWM) for full and half bridge DC to AC inverter. Their control strategy consists of a versatile modulator capable of synthesizing triggering signals for various frequency based on digital implementation. While the ones in [6] used FPGA to evaluate the performance of several PWM deadbeat control methods in single and three phase inverters at low carrier frequency[7]. PWM generation methods have been changed continuously in order to achieve a better performance. Sometimes, the intended operation conditions can be achieved by using either different types or architecture, while in others alternative solutions must be obtained to reach this goal. The authors in [8] built a one-comparator counter-based PWM control scheme using an FP-GA board for controlling a phase-shift Zero Voltage Switching (ZVS) DC-DC full-bridge converter while the ones in [9] used a low-cost FPGA to generate space vector PWM (SVPWM) waveforms for three-phase voltage-sourced inverters (VSIs). In the suggested model, the off-line computations of the occupied times according to various modulation index and phase angle are stored in EPROM (erasable programmable read-only memory), which allows a microprocessor-free design. The main advantages of the presented model are; high-speed response, precise switching, and flexible adjustment of dead time and switching frequency which makes it suitable to drive various switching devices in practical applications. A combined PWM- PFM (Pulse Frequency Modulation) technique was presented in [10] to control the switching operation of DC-DC converters. The mode of operation changes from PWM to PFM and vice versa based on the variations in the load condition. The performance efficiency of the proposed method was evaluated by calculating the conduction losses, switching losses, and ripple voltages at different load values. A new random PWM technique for a full-bridge DC-DC converter was developed in [11]. It was compared to other PWM techniques with constant switching frequency and random PWM technique based on the efficiency and harmonic spreading factor. The proposed scheme spreads the harmonic clusters and gives constant average inductor current to reduce the output voltage ripple. FPGA based PWM controllers have been used not only in converters’ applications but also in induction and synchronous