一种旋转变压器双采样差分位置解码方法  

A Dual-Sampling Differential Position Decoding Method for Resolvers

作　　者：吴春 应王瑞 郑露华 成凤敏 支恩 Wu Chun;Ying Wangrui;Zheng Luhua;Cheng Fengmin;Zhi En(College of Information Engineering Zhejiang University of Technology,Hangzhou 310023 China)

机构地区：[1]浙江工业大学信息工程学院,杭州310023

出　　处：《电工技术学报》2024年第15期4896-4908,共13页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(52007169);浙江省自然科学基金(LY23E070004)资助项目。

摘　　要：针对旋转变压器解码芯片价格高及常规软件解码方法精度不足等问题,提出一种旋转变压器双采样差分位置解码方法。该方法通过主控芯片产生一路方波信号,并对方波信号进行滤波、放大后产生同频率正弦信号作为旋转变压器激励信号。同时,主控芯片在一个激励周期内触发两次模数转换器(ADC)采样,即对旋转变压器输出的正、余弦信号实施双采样。并计算两次采样值的差分,得到与位置相关的正、余弦包络线信号。最后通过锁相环估计转子位置和速度。所提双采样差分位置解码方法可消除正、余弦信号偏置波动对位置估计的影响,且解调信号幅值增大一倍,可提高位置解码精度。实验结果表明,所提双采样差分位置解码方法,相比常规软件解码方法,位置估计精度更高,电机稳态和动态性能更好。Resolver decoding chips are usually used to obtain the rotor position in high-reliable applications,such as electric vehicles,robots,aerospace,etc.Nevertheless,there are some defects of high cost and complex peripheral circuits,which restrict wide applications in compact and low-cost driver systems.In recent years,some software decoding methods of resolvers have been proposed,but most of them suffered from extra components and low precision due to bias drift of sineand cosine signals.To address these issues,this paper proposes a dual-sampling differential position decoding method for resolvers.By sampling peaks and bottoms of the output signals of resolvers twice in one excitation period,the influence of bias drift of sine and cosine signals on the sampling accuracy is eliminated and the position decoding accuracy canbe improved.Firstly,the main control chip generates a fixed PWM signals,such as 8 kHz in the paper,which are amplified to excite the primary windings of resolvers.Secondly,after processing the sine and cosine signals generated by the secondary windings of resolvers through the signal processing circuits,the sine and cosine envelope signals required by the software decoding are prepared.Thirdly,a differential dual sampling of the peaks and bottoms of the signal envelopes can increase the amplitude of the signals by onetime and eliminate the influence of the bias voltage of sineand cosine signals.Finally,a second-order PLL is adopted to track the rotor position of the resolvers in comparison with a third-order PLL and arctan function.The results of dual-sampling position decoding and single-sampling position decoding methods are compared with the actual position measured by a 2500-line photoelectric encoder.It is found that under the condition of 600 r/min,the position error of the dual-sampling method is within±1.5°and that of the single-sampling method is within±5.4°,which proves that the dual-sampling differential position decoding method has better steady-state performance.In the acceleration a

关 键 词：旋转变压器 软件解码 双采样 差分计算 

分 类 号：TM35[电气工程—电机]