Search

Power Processing Unit(PPU) is the central part of the xenon ion electric propulsion system, and its size, weight, and key technical difficulties usually exceed the thruster itself. The high-power and high-output-voltage power supplies, such as beam supply and anode supply, are the main parts of the electric propulsion power system. In this paper, a two power stage beam supply topology is proposed to meet the requirement of multi-mode electric propulsion system. The front stage is an interleaved boost converter, which is adopted to adjust the total output voltage. The second stage is based on a full-bridge resonant converter able to provide very high output voltage, which operates the fixed optimum switching frequency. The power converter control strategy and design principles of magnetic components are studied and finally the corresponding experimental results are given to validate feasibility of the proposed converter in this paper.

For DC off-grid photovoltaic power generation system, when the power demand of DC bus is large, Maximum Power Point Tracing(MPPT)is needed to keep the solar panels in the state of maximum power output for the output voltage and power are affected by temperature and illumination evidently. When the power demand is small, all converters working at the same time will lead to low efficiency of light load. The most simple and direct way to improve is to reduce the number of working modules, so as to ensure that the power system can achieve energy conversion efficiently within the full range. In order to solve the above problems, this paper proposes a control strategy for power generation system. This strategy makes full use of the solar array and adjusts the number of working modules dynamically according to the load demand. It provides a rationale for improving the operation efficiency of DC off-grid photovoltaic power generation system within the full load range. Finally, the effectiveness of the scheme is verified by simulations.

The space solar array simulator(SSAS) simulates the output characteristic curve of the solar panel under various load conditions, which is used to complete the performance test of the tested power system, and is widely used in the field test field of the spacecraft power system. However, in the actual test environment, the long test cable between the solar array simulator and the power supply of the spacecraft being tested seriously affects the simulation accuracy of the output curve of the solar array simulator. Therefore, the compensation connection line is generally used to remotely compensate the output voltage of the simulator. This paper proposes a simple method to detect the connection state of the remote voltage compensation terminal connection line, and gives a normalized fault state judgment standard. This method is not only suitable for solar array simulator equipment, but also for any high-power power supply where remote voltage compensation is required for the output voltage.

The solar array drive assembly (SADA) slip ring is a critical link that provides electrical power and electric signal transmission between solar arrays and satellite power systems, which is prone to arc faults in the space environment. If these arc faults cannot be detected and eliminated quickly enough, they will seriously threaten the safety of the satellite power system and the satellite. In this paper, a fast arc detection method based on fractal dimension is proposed that adapts to different operating modes of power systems. The detection method collects the current differential signal data flowing through the SADA slip ring, and, according to the trend of the fractal dimension change in this signal, the fault identification algorithm is designed for different operating modes of the power system to achieve real-time and rapid identification of arc faults. Finally, the effectiveness of the proposed method is demonstrated using test data under several different fault conditions. [ABSTRACT FROM AUTHOR]

For the high power solar array simulator, the requirements such as high power, miniaturization and modularization are higher. In this paper the total power of the simulator is 2.4 kW with the chassis height is no more than 2U. The forced air cooling is adopted. The modular structure is used in the forced cooling system according to the electrical connection requirement. The chassis is divided into three parts, the linear, the multilevel and the Vicor module. And the independent cooling air duct system is set up for each part. The contractile air duct of the multilevel and the Vicor part are optimized mainly. The forced air cooling system with the optimization design can satisfy the high power density requirements of the simulator. The maximum case temperature of the components can be controlled under 88 ℃, and all the devices in the simulator can work safely and reliably. The results are verified by both finite element simulation and thermal test.

Aiming at the limited fault diagnosis and performance monitoring capabilities problem of satellite power control unit (PCU), the testability design is done for the PCU and the on-orbit fault diagnosis and performance monitoring system based on BIT technology is built. The BIT module consists of three analog boards and one core board. The analog board can perform high-speed sampling of dozens of analog signals, while the core board can run fault diagnosis and performance monitoring algorithms, and other works such as data storage, data packaging, and communication. The result of fault diagnosis and performance monitoring is sent to the communication interface after packaging. The verification experiment shows that the system can accurately detect and locate the fault of the PCU fastly without affecting the normal operation of the PCU. Meanwhile the performance of the PCU, such as bus voltage ripple, can be monitored.

A family of interleaved boost converters and an original systematic derivation method based on the two-phase interleaved inverse-coupled inductor concept are proposed in this article for battery discharging in spacecraft applications. The family, including 14 converters, is generated by interconnecting multiple pulsating voltage cells through the energy storage cells. The basic pulsating voltage cells are derived from an inverse-coupled boost converter, and the energy storage cells include an inductor cell, tapped inductor cell, flyback cell, buck-current-fed cell, and partially current-fed cell. The proposed family of converters achieves high efficiency, step-up power conversion without the right-half-plane zero effect, continuous output current and low side switch driver. The operational principle and small-signal analysis of a representative topology in the proposed family of converters are discussed in detail. Moreover, experimental and simulation results are presented to verify the feasibility and effectiveness of the developed converter. Finally, the characteristics of the proposed family of converters are compared with other state-of-the-art converters. [ABSTRACT FROM AUTHOR]