一种提高原边反馈AC/DC恒流精度的方法

摘要

针对传统原边反馈AC/DC由于峰值电流检测不准造成的输出恒流精度较低的问题，文中提出了一种应用于原边反馈的高精度恒流控制方法。该控制方法引入Ipk斜率检测来估计真正的原边峰值电流，以此提高输出恒流精度。通过LED驱动电路实验，验证结果表明，相比传统电路，此方法提高了恒流输出精度，在85～265 V输入电压范围下，恒流精度约为2％。%A high-precision control strategy for the primary-side regulated AC /DC is proposed to deal with thelow precision of constant current owing to the inaccurate peak current detection by the conventional primary -side regulatedAC/DC.The control strategy estimates the real primary peak current by use of the slope detection of Ipk to improveconstant output current precision .Experimental measurements of the LED driver circuits are presented to verifythe performance of the proposed control strategy .The strategy improves constant output current precision and can a -chieve about 2% output current tolerance for 85 ~265 V input voltage range.