tery can not be charged in time, and almost all the power of it is released. Because of
“memory” of the battery, the voltage can not reach the rated voltage after the battery
is charged. To prevent this from happening, there are two batteries in the system.
3   Software Design
When the certain intensity of light can not be detected by the photosensitive sensor,
the system can check the clock. If the time is more than 7 am, the system is set to
cloudy state. The system can calculate the azimuth angle and the height of sun at noon
by the time, the local latitude and longitude, etc., while the stepper motors will make
the solar panels turn to the location. Then the system continues to detect light inten-
sity. When the weather is sunny, the state of the system will be changed. The system
will not aimlessly search for sunlight. When the voltage of the main battery is below 10 volts, the battery will stop dis-
charging. At the same time, the spare battery will supply power. After the main battery
is charged by the solar panels, the main battery will supply power again. When the
system is in extreme circumstances and the voltage of the spare battery is below 10v,
the solar panels can not supply power for the main battery. The commercial electricity
will supply power for the device. The battery protection circuit is shown in Fig. 5.
The light intensity of four directions will be detected by four photosensitive sen-
sors in the sunny day. When the light intensity of the corresponding direction is
different, MCU will control device to turn to the suitable location where the light
intensity of the four directions is same. When the battery is over-discharging, the sys-
tem will automatically use a spare battery or the external power to supply power. The
battery can be protected, and the system can continuously run in this way. Program
flow chart is shown in Fig. 6.摘要：混合双轴太阳能跟踪系统的设计目的是为了提高太阳能电池板的发电效率。传感器信号之间的差别可以通过系统来判断，并且为驱动太阳能电池板跟踪太阳可以通过步进电机来控制。与此同时，系统可以计算太阳的仰角和方位角来驱动太阳能电池板在多云情况下，在给定信息条件下达到最佳位置。双重跟踪方法的优点是在不同的情况下相互互补，因此太阳能电池板发电的效率也被提高了。电池的保养是考虑到当太阳能电池板不能正常工作。该
系统的运动特性也被进行分析用来验证设计的可行性。
关键词：跟踪太阳，复合轨道控制系统，AVR MCU
1引言    因为太阳能是一种清洁的能源，所以许多的太阳能设备已被广泛的使用。然而，设备的低转换效率仍未被解决。就太阳能电池而言，它们可以被分为四类。即，单晶硅太阳能电池、多晶硅太阳能电池、无定形硅太阳能电池以及薄膜硅太阳能电池。单晶硅太阳能电池的光电转换率是最高的。理论转换效率为24％至26％。但目前工业规模化生产的转换效率是17％左右。然而，单晶硅太阳能电池成本高，生产过程复杂并且要去促进其使用也有难度。所以常用于商业的太阳能电池是薄膜硅太阳能电池和多晶硅太阳能电池。多晶硅电池的理论转换效率是20％左右，其实际的生产效率是12％〜14％[1]。由于薄膜硅太阳能电池的成本低，所以其在市场的的份额呈逐年上升的趋势。虽然在德国弗劳恩霍夫太阳能系统研究所所开发的薄膜太阳能电池的转换效率已经达到了24.2％，这也是欧洲该领域的是最高纪录[2]。然而商用的薄膜电池的转换效率仅约6％至8％[3]。可以看出，薄膜硅太阳能电池的实际转换效率是远低于其理论值的。因此，需要开发新方法来提高转换效率。大多数目前使用的太阳能装置是固定一个朝着天空的角度并且设计师计算出这个最佳角度可以最大限度地提高太阳能收集[4]。作为太阳位置随时间的变化，有必要采用的太阳能跟踪的移动设备以改善太阳能的利用率。以往的研究表明，由双轴太阳跟踪系统太阳能吸收是高于35％的固定的系统[5]。因此，太阳跟踪控制系统的研究是必要的。 太阳能跟踪系统英文献和中文翻译(3):http://www.youerw.com/fanyi/lunwen_5515.html