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6 Power Technology of Lunar Lander
incident angle, while the solar incident angle was greater than 45°, the power output
of the solar array was worse with increasing of the solar incident angle.
6.4.3 Lightweight Design
The lunar lander had limited mass resources. In order to achieve lightweight, the
power system had been specifically designed from both system and instrument levels.
For example, such design of the Chang’E-3 lunar lander is given as follows.
1. System-Level Optimization Design
The Chang’E-3 the lunar lander consisted of the lunar lander and the lunar rover.
The interface between the lander and the rover was complex. The power supply
requirement was different during all flight phases. To improve the efficiency of power
supply and optimize the energy configuration of system, the system-level joint power
supply design was necessary, which will be introduced in the following sections.
2. High Specific Energy/Power Product Design
The major contents of optimization design of the power supply controller included
configuration, structural component optimization, and selection of components and
parts. In configuration design, the modular design could reduce internal cables
and volume. In structural optimization, the thermal characteristics of the separately
installed components were analyzed to optimize their structure, with aluminum alloy
for structure and titanium alloy for the rods with high strength and stiffness. In selection of component and part, lightweight and small units were selected for electrical
connectors, relays, and magnetic cores, and reduce the number of filter capacitor
arrays and the size of the filter inductor core by increasing the frequency of the
discharge circuit.
The wires, strips, silicone rubber, and fasteners in lithium-ion battery packs were
determined by electrical properties and mechanical properties, so it was not easy to
reduce weight. Therefore, the weight could only be realized by reduction of structural
parts such as lithium ion battery cells and its wall plates as follows.
(1) New material. The use of high-strength materials such as titanium alloys and
carbon fiber-reinforced composite materials instead of traditional structural
materials such as stainless steels and aluminum alloys could reduce the mass
while structural strength was ensured.
(2) Reduction of material. The mass of material could be reduced by reduction of
the thickness or shortening of the length to reduce the amount of the current
collector material while the material properties met the requirements of the
product performance.
(3) Reduction of redundant design. Because the lithium-ion battery technology was
matured and stable, the redundancy of single battery design could be reduced
appropriately.
6 Power Technology of Lunar Lander
incident angle, while the solar incident angle was greater than 45°, the power output
of the solar array was worse with increasing of the solar incident angle.
6.4.3 Lightweight Design
The lunar lander had limited mass resources. In order to achieve lightweight, the
power system had been specifically designed from both system and instrument levels.
For example, such design of the Chang’E-3 lunar lander is given as follows.
1. System-Level Optimization Design
The Chang’E-3 the lunar lander consisted of the lunar lander and the lunar rover.
The interface between the lander and the rover was complex. The power supply
requirement was different during all flight phases. To improve the efficiency of power
supply and optimize the energy configuration of system, the system-level joint power
supply design was necessary, which will be introduced in the following sections.
2. High Specific Energy/Power Product Design
The major contents of optimization design of the power supply controller included
configuration, structural component optimization, and selection of components and
parts. In configuration design, the modular design could reduce internal cables
and volume. In structural optimization, the thermal characteristics of the separately
installed components were analyzed to optimize their structure, with aluminum alloy
for structure and titanium alloy for the rods with high strength and stiffness. In selection of component and part, lightweight and small units were selected for electrical
connectors, relays, and magnetic cores, and reduce the number of filter capacitor
arrays and the size of the filter inductor core by increasing the frequency of the
discharge circuit.
The wires, strips, silicone rubber, and fasteners in lithium-ion battery packs were
determined by electrical properties and mechanical properties, so it was not easy to
reduce weight. Therefore, the weight could only be realized by reduction of structural
parts such as lithium ion battery cells and its wall plates as follows.
(1) New material. The use of high-strength materials such as titanium alloys and
carbon fiber-reinforced composite materials instead of traditional structural
materials such as stainless steels and aluminum alloys could reduce the mass
while structural strength was ensured.
(2) Reduction of material. The mass of material could be reduced by reduction of
the thickness or shortening of the length to reduce the amount of the current
collector material while the material properties met the requirements of the
product performance.
(3) Reduction of redundant design. Because the lithium-ion battery technology was
matured and stable, the redundancy of single battery design could be reduced
appropriately.