Alternating Current (AC) motors play important roles across various fields. Traditional processors utilizing Sine Pulse Width Modulation (SPWM) to control the speed of AC motors face challenges such as high computational complexity and limited flexibility. To address these problems in the variable frequency speed control process of AC motors, this paper proposes the design of a System-on-Chip (SoC) capable of generating SPWM waves. Our proposal is based on an open-source Reduced Instruction Set Computer fifth-generation (RISC-V) processor. The proposal is verified on the Field Programmable Gate Array (FPGA) platform. The results demonstrate that, with the sine wave frequency set to 3200 Hz and the triangular wave frequency set to 15 KHz, our proposal achieves a 413× acceleration compared to the traditional software method. Compared to the previous accelerator, our design reduces (Look-Up-Table) LUT consumption by 41.10% and (Total Harmonic Distortion) THD by 17.79%.