基于频率跟踪控制的串联谐振变换器研究

在石油钻井随钻仪器的供电系统中,常采用泥浆发电机供电。由于电机的转子和定子在结构上是分离的,所以转子侧的直流电不能直接给定子侧的随钻仪器供电,于是引入了一个具有可分离变压器的串联谐振全桥变换器来实现功率耦合。分析了串联谐振全桥变换器的特性,针对井下高温环境,谐振参数随温度变化较大,引入了谐振频率跟踪控制,使变换器始终工作于谐振频率处,保证电机转子与定子侧的最大功率耦合。给出了控制环路的设计,实验证明,频率跟踪控制能很好地跟踪谐振频率,实现最大功率耦合。

Study of Series Resonant Full-bridge Converter Based on Frequency Tracking Control

In the power supply system of petroleum drilling,a mud generator is often used to supply power for the instru-merits while drilling.Because the rotor and stator of mud generator are separated structurally,the DC power of rotor sidecan't dimcfly supply power for instruments while drilling in the stator side.So a series resonant full-bridge converter which has a separate transformer is introduced to couple power.This paper analyses the characteristics of series resonant full-bridge convener.Aiming at the underground high temperature environment.the resonant frequeney tracking control owing to the great variation of resonant parameters with temperature is introduced to ensure the convener always working at reso-nant frequency for the maximum coupled power from the rotor side to the stator side.Then the design of control loop is provided.Eventually,the experimental verifications are presented.The results show that resonant frequency tracking control can work very well and realize the maximum coupled power.