原边反馈方式的反激式变换器通过辅助绕组来间接采样输出电压的信息，从而省去了副边反馈方式必须用到的光耦和TL431，这使得它的待机功耗，成本和体积都大大降低。原边反馈的诸多优点使得它在更重视便携，低待机功耗和低成本的中小功率AC/DC市场得到了非常广泛的应用。.虽然原边反馈有诸多的优点，但是弊端也很多。首先，传统的原边反馈变换器只能工作于断续模式，这限制了它的功率密度的提升；其次，采样信息包含了二极管和寄生电阻的压降，使得输出电压精度差；最后，受采样速度的限制，其动态响应能力差。以上弊端都限制了原边反馈变换器的应用范围。本项目基于原边反馈方式的反激拓扑结构，针对于如何提升系统的功率密度和工作效率，降低系统的待机功耗；如何提升系统的恒流恒压输出精度；如何提升系统的动态响应速度等科学问题提出了完整的解决方案，包括：多模式大功率原边反馈变化器架构，高精度恒流恒压控制电路，以及动态响应加速电路等。

Primary–side feedback flyback converters sense the output information indirectly through the auxiliary winding which can obviate the need for the opto-coupler and TL431. The power loss of the feedback loop is decreased because of the elimination of these two devices. So, it is easy to achieve low standby power consumption, low cost and low volume. Due to these advantages, primary-side feedback flyback converters have been widely used in small to medium power AC/DC applications, which is more emphasis on portability, low standby power consumption and low cost..However, primary-side feedback solution also has many drawbacks. First, traditional primary-side regulation converters can only works in DCM (discontinuous conduction mode), so it is hard to improve the power density of them; second. Second, the auxiliary winding voltage contains not only the output voltage but also the voltage of the secondary-side rectifier diode and parasitic resistor making it very hard to precisely regulate the output voltage. Third, limited by the sampling velocity, primary-side regulation converters suffer from poor dynamic response. In this project, a complete system solution plan is proposed based on primary-side regulation control method aiming at how to improve the power density and system efficiency, how to decrease system standby power, how to improve system constant current and constant voltage accuracy, and how to speed up system dynamic response, including: multi-mode high power PSR converter structure, high precision CC/CV control circuit, and dynamic response accelerating circuit.