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6 Power Technology of Lunar Lander
For the Chang’E-3 lunar lander, after the lunar lander was landed on lunar surface,
the lander rover was powered by the lunar lander through separation plug. Due to
limitations of temperature and TT&C conditions, the separation of the lander and the
rover should be accomplished as soon as possible. Before the separation, the camera
of the lunar rover would take photograph of lunar terrain near the landing site by
the navigation cameras and panorama cameras. The working time was long and the
load power was relatively high. The solar array of the lander would supply power to
the rover main bus and charges the battery packs of the lander and the rover. After
the battery pack of the rover was fully charged, the rover could be separated. It was
necessary to analyze of the power out of solar array of the lander accurately to ensure
the safety and reliability of separation.
The rover was on the top of the lander before separation, part of the solar array
of the lander was occluded by the rover before it was deployed. The power output of
the solar array of the lander was up to not only the solar incident angle but also the
occlusion before separation of the rover.
In order to accurately analyze the occlusion area of the solar array, the solar array
was divided into grids. Generally, the smaller the grid of the solar array was, the
higher the accuracy was in analysis of occlusion. But at the same time, the larger
the calculation burden was. Therefore, it should be traded off in actual occlusion
analysis. Due to the special configuration of the solar array of the lunar lander and
the size of the solar cells, when the occlusion analysis was conducted, the mesh was
divided as follows.
(1) For regular area of substrate structure of the solar array, the rectangle grid was
used.
(2) For irregular part of the solar array, because the irregular part of the solar array
was trapezoidal, it was divided into small trapezoids when the grid was divided
and the bottom side of upper trapezoid coincided with the top side of lower
trapezoid.
The grid of the solar array of the Chang’E-3 lunar lander is shown in Fig. 6.2.
Fig. 6.2 Grid of the solar array of the Chang’E-3 lunar lander
6 Power Technology of Lunar Lander
For the Chang’E-3 lunar lander, after the lunar lander was landed on lunar surface,
the lander rover was powered by the lunar lander through separation plug. Due to
limitations of temperature and TT&C conditions, the separation of the lander and the
rover should be accomplished as soon as possible. Before the separation, the camera
of the lunar rover would take photograph of lunar terrain near the landing site by
the navigation cameras and panorama cameras. The working time was long and the
load power was relatively high. The solar array of the lander would supply power to
the rover main bus and charges the battery packs of the lander and the rover. After
the battery pack of the rover was fully charged, the rover could be separated. It was
necessary to analyze of the power out of solar array of the lander accurately to ensure
the safety and reliability of separation.
The rover was on the top of the lander before separation, part of the solar array
of the lander was occluded by the rover before it was deployed. The power output of
the solar array of the lander was up to not only the solar incident angle but also the
occlusion before separation of the rover.
In order to accurately analyze the occlusion area of the solar array, the solar array
was divided into grids. Generally, the smaller the grid of the solar array was, the
higher the accuracy was in analysis of occlusion. But at the same time, the larger
the calculation burden was. Therefore, it should be traded off in actual occlusion
analysis. Due to the special configuration of the solar array of the lunar lander and
the size of the solar cells, when the occlusion analysis was conducted, the mesh was
divided as follows.
(1) For regular area of substrate structure of the solar array, the rectangle grid was
used.
(2) For irregular part of the solar array, because the irregular part of the solar array
was trapezoidal, it was divided into small trapezoids when the grid was divided
and the bottom side of upper trapezoid coincided with the top side of lower
trapezoid.
The grid of the solar array of the Chang’E-3 lunar lander is shown in Fig. 6.2.
Fig. 6.2 Grid of the solar array of the Chang’E-3 lunar lander