The Study On The Digital Control Of Communication Power Supply

With the development of information society,electro-equipments have more requirements for high quality power. Due to its special advantages, digital control becomes a new research direction in power supply. In this paper, some reasearch on the digital control in power electronics are accomplished.In this paper, the digital control's characteristics, advantages and the current market situation are introduced at first, including the challenges of the digital control faced in use. some research on the digital control in power supply are accomplished, such as the influence of sampling holding and delay, digital control strategy, how to improve the accuracy of communication power supply and other main questions which existed in digital controlled system.In this paper, the digital control of communication power supply is studied. Firstly, the DC/DC converter mathematics model is discussed and the proposed methods of the digital controller design are frequency response method, digital PID control algorithm and fuzzy adaptive PID control algorithm. The effects of zero-order holding, sampling and computation delay are consider in frequency response method, the designed digital controller is very accurate, but the dynamic performance is poor when the load changed in a wide range. Digital PID algorithm is relatively simple and it still plays an important role in digital control of the converter. The fuzzy adaptive PID control algorithm is flexible. According to the changes of the output voltage, automatically adjusts PID parameters can greatly improve the converter's dynamic performance. In the light-load or unload, it is feasible to reduce the switching frequency, which can prevent system oscillating, reducing the output voltage ripple.In order to achieve such control strategy, a set of HOW communication power supply is designed. The control chip is based on TI's TMS320F2801, the half-bridge converter as experimental platform, the digital control and digital management is implemented on the communication power supply.The experimental result showed that the control scheme has good control performance and simple control arithmetic. The strategy is a simple and practical digital control method.