EMC techniques in Household Electric Appliances and Wide Use Electric Apparatus

重点研究和讨论了降低家用电器和广泛使用的电器中高次谐波的电磁兼容技术。通过本项目的研究，取得了以下成果。对其他研究人员开发的功率因数校正转换器的特点进行了研究和总结。因此，单级变流器是在两级变流器的基础上，通过将两个半导体开关组合成一个公共开关来减少电气部件而产生的。但是，由于电流应力的增大，PFC变流器中的功率损耗也随之增加。为了克服这一问题，提出了两种不同类型的PFC变流器并联的混合-并联PFC变流器。该变流器通过调节两个变流器之间的功率来实现高效率和高功率因数。通过控制占空比，可以得到较小的输出电压纹波。2.讨论了采用均流控制器的并联模块PFC变流器系统的特点。将在并联DC/DC变换系统中广泛应用的平均均流控制应用到PFC变换中。结果表明，在传统的程控电流型PFC变流器的电流基准上加入均流信号，实现了稳定的均流控制和快速响应。通过调节电压反馈回路的响应，不会引起功率因数的下降。

EMC techniques especially for decreasing higher harmonics in Household Electric Appliances and Wide Use Electric Apparatus are investigated and discussed. Following results are obtained by this project.1. Characteristics of PFC converter which have been developed by other researchers are investigated and summarized. As a result, one-stage converters are derived from two-stage converter by combining two semiconductor switches into one common switch to decrease electric parts. However, power losses in the PFC converter are increased due to the increase of current stress. In order to overcome this problem Hybrid-Parallel PFC converter where two different types of converters are connected in parallel is proposed. By using this converter, high-efficiency and high power-factor are achieved by adjusting the power between two converters. Small output voltage ripple can be derived by controlling the duty ratio.2.Characteristics of parallel-module PFC converter system with current-sharing controllers are discussed. Averaged current-sharing control which are widely used in a paralleled DC/DC converter system are applied to the PFC converter. As a result, stable current-sharing control and fast response are archived by adding the current-sharing signal to current reference in conventional current-programmed mode PFC converter. No degradation of power factor is occurred by adjusting the response of voltage feedback loop.