高功率因数无电解电容电机驱动系统电流控制策略

Current control strategy of high power factor electrolytic capacitor-less motor drive

因成本与使用寿命上的优势,无电解电容电机驱动技术正逐步得到应用。然而,由于仍存在相电流幅值过大与弱磁控制不稳定的问题,直接影响了该技术的推广。为此,提出一种单相输入高功率因数无电解电容电机驱动的电流控制策略。通过调整交轴电流指令的轨迹,使驱动器输入侧具有高功率因数,且电机相电流峰值比以往方法有明显削减;对弱磁失控现象,提出基于交轴电压修正的弱磁控制方法。在变频空调压缩机控制系统上的实验验证了该电流控制策略的有效性。实验结果表明,该控制策略能在输入电流满足IEC谐波标准的前提下,使电机相电流峰值降低,并确保弱磁控制环路的稳定性。

Because of tiie advantages in cost a n d life s p a n, single p h a s e input electrolytic capacitor-lessmotor drive is getting more and more c o n c e r n. H o w e v e r, this technique is not widely u s e d for the reasonsof several key problems, s u c h as larger p h a s e current m a g n i t u d e a n d instability of field w e a k e n i n g c o n-trol. To overcome these problems, a novel current control strategy for electrolytic capacitor-less m o t o rdrive was proposed. By adjusting the w a v e f o r m of quadrature-axis current c o m m a n d, the high p o w e r fac-tor was achieved and m o t o r p h a s e current m a g n i t u d e w a s obviously r e d u c e d. T o solve the field winstability problem, an enhanced field w e a k e n i n g control met!iod b a s e d o n quadrature-axis voltage modifi-cation was proposed. The experiments o n a variable s p e e d air-conditioner demonstrate effectiveness of the proposed method. The results s h o w that, b y using the p r o p o s e d m e t h o d, the input cmonics restrictions in IEC s t a n d a r d, a n d the m o t o r p h a s e current is considerably rstability of field weakening control c a n b e g u a r a n t e e d.