1、 xx 大学学士学位论文 - - - I - 新型复合开关及动态无功补偿系统的研究 摘要 电力系统运行的经济性和电能质量与无功功率有重大的关系。无功功率是电力系统一种不可缺少的功率。大量的感性负荷和电网中的无功功率损耗，要求系统提供足够的无功功率，否则电网电压将下降，电能质量得不到保证。因此，无功补偿是电力系统的重要组成部分，它是保证电能质量和实现电力系统经济运行的基本手段。 本文针对电磁开关和电力电子开关投切电容器的无功补偿装置应用中存在的问题，开发、研制了一种基于复合开关投切电容器的无功补偿装置。本装置采用过零投切的复合开关模块投切电容器，其内部集 成的单片机、过零检测及触发电路能根据需要
2、确保晶闸管在电压过零时导通，稍后继电器短接 ；外部控制信号消失后，继电器断开，稍后晶闸管关断，避免了投切时产生的大冲击电流，从而在硬件电路上实现电容器组的无过渡过程的快速投切，且硬件设计简单可靠。 另外，本文详细分析了补偿装置及复合开关控制器的软硬件结构。控制系统采用性价比高的 ATmegas 单片机作为主控制系统主体。试验和现场运行情况表明 :该装置能够实现无功功率的快速、准确补偿且成本较低，在低压网中具有较好的实用价值及广阔的应用前景。 关键词 无功补偿；复合开关；单 片机 xx 大学学士学位论文 - - - II - Studies on the New Complex Switch a
3、nd Dynamic Reactive Power Compensation System Abstract Power system operation efficiency and power quality have significant relationship with reactive power. Reactive power is an indispensable electric power system of power.The loss of perceptual load and reactive power， the system must provide suff
4、icient reactive power and voltage， otherwise will fall, the power quality not guarantee. Therefore, the reactive power compensation is an important part of power system, it is the basic means to guarantee the quality of electric power system and realize the economic operation. Aiming at the disadvan
5、tages in the application of reaetivepower compensation device with electromagnetic or power electronic switches for Pulling in or out the capacitor， a reactive power compensation device based on the complex switch，which can realize grading and fast compensation for each phase using both collective c
6、ompensation and separate compensation， is developed to switch capacitor.Interior single-chip and zero-cross detection&triggering circuit of it insure that thyristor is triggered in the zero-voltage condition， then relay is shorted， relay is switched off when outer control singal is disappeared， and
7、after a while so does thyristor in the zero-current， thus greatly reduced surge current. This sort of switch circuit achieved switching of capacitors without tnaansition course and was simple and reliable. The thesis also analyzed the hardware and software of controller about complex switch and compensation deviced in detail.ATmega8 was a sort of cheapSingle Chip computer and was applied to control system.The test shows that this device can fleetly and truly compensate reactive power and be used in low network. Keywords Reactive Power Compensation； Complex Switch； Single-chip Computer
