PLIU

Objectives

The project concerns the development and qualification of two modules of the Payload Distribution and/or Interface Units. This development will increase the range of potential Platforms that can implement this unit and will avoid problems with export restrictions (ITAR free design).

The two modules are:

RT1553 module: This module forms the interface between the 1553 external bus and the internal OBDH bus.

CVIU module: This power supply module needs to be redeveloped in order to cover the full range of potential MAIN BUS voltages (28V, 50V, 100V) with ITAR free solution.

The objective of the project is to develop and qualify two RDIU/PLIU/PLDIU modules that allow covering a larger range of telecommunication platforms by increasing the range of Primary Power Bus voltages. In addition, export restrictions are avoided by implementing ITAR free solutions.

Two modules are concerned:

  • CVIU module: This module provides the internal supply voltages of the complete unit. It needs to be redeveloped in order to cover the full range of potential MAIN BUS voltages (28V non regulated, 50V, 100V) with ITAR free solution.
  • RT1553 module: This module forms the interface between the 1553 external bus and the internal OBDH bus. It needs evolution to become ITAR free and replace obsolete EEE parts.

Two RT1553 modules (Nominal and Redundant) together with two CVIU modules (Nominal and Redundant) constitute the centralized management core of Power Distribution and Interface Units for export telecommunication payloads.

The main activity consists in the design, development and qualification of these two modules.

RT1553 module
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CVIU module
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Challenges

The key issues in this project are:

  • Increase main power bus application range up to 100V,
  • Documentation including PLIU equipment documentation (for topics related to module), CVIU and RT1553 module documentation,
  • EM of CVIU (50V) and RT1553 module,
  • Testing and reporting at CVIU and RT1553 module level,
  • Qualification testing and reporting at unit level.

Benefits

Thanks to this new development, the next generation of Power Distribution and/or Interface Unit dedicated to export Payloads will allow to extend the customer range and selling of 3 to 4 PLIU/RDIU/PLDIU per year is expected.

This new generation allows to enlarge the product portfolio:

  • With capacity to cope with a large range of platforms, ideally all the platforms, whatever the Primary Power Bus,
  • With ITAR free solution as target,
  • With capacity to propose different types of Power Distribution and/or Interface Units reusing the same core (2 CVIU + 2 RT1553) completed by a large range of standard modules developed and qualified for Thales Alenia Space SB4000 satellites.

Features

The PLIU/RDIU/PLDIU is in charge, under control of the platform main computer, of one or several of the following functions:

  • Distributing commands and collecting telemetry to/from the Payload units,
  • Providing power distribution outputs to the Payload units and heaters,
  • Performing the acquisition of thermistors,
  • Controlling the motors dedicated to antenna pointing,
  • Providing commands to pyrotechnic devices.

The overall PLIU/RDIU/PLDIU architecture is based on the following concept:

  • Use of two interface functions with both the external 1553 communication and Primary Power Bus, in cold redundancy, generating one internal OBDH communication bus, and the protected power voltages dedicated to supply the several board of a RDIU/PLIU/PLDIU. These interface functions are located on the two boards CVIU for the power bus interface, and RT1553 for the 1553 bus, and constitute the centralised management core of the PLIU/RDIU/PLDIU.
  • Use of different standard modules to provide the different TM/TC and distribution functions with the Payload units, each board being able to interface with both centralised management cores.

The PLIU/RDIU/PLDIU must fulfil the following key parameters:

  • Compatibility with the complete range of customer platforms:
    • Power bus: Non regulated 26V to 42V; 50V or 100V,
    • Digital bus 1553 interface.
  • High degree of flexibility to answer to a large range of payload with minimum non recurring cost,
  • ITAR free allowing to answer to programs submitted to export control constraints.

The proposed architecture for the new CVIU module will allow to easily adapting to large Primary Power Bus range in order to be compliant to all platforms whatever the Main Power Bus voltage range. This module will reuse DCDC converter topology already developed and largely used for DCDC converter implemented in RF Payload units. The new module will use only ITAR free parts.

The RT1553 module performs the TM/TC interface with the redundant MIL1553 bus. It uses two main parts which are a microcontroller and a dedicated FPGA.

The current micro-controller being an ITAR part is proposed to be replaced by a non- ITAR one. Furthermore, it is envisaged to replace the current FPGA (no more used on other projects) by another one which is currently used on various projects at TAS in order to avoid obsolescence risk in short or mid-term.

RDIU Example


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Plan

The development activities are:

  • Design, development and documentation of the new CVIU and RT1553 boards including 50V and 100V version for CVIU.
     
  • CVIU (only 50V version) and RT1553 EM boards manufacturing and electrical validation testing including complete electrical tests at ambient, hot and cold temperatures and emission and susceptibility conducted EMC tests on Main Power Bus for CVIU.
     
  • Qualification of the new modules on a complete PLIU PFM.
    • This approach of qualification on the first PFM is acceptable due to the large reuse of existing modules for the other RDIU functions and because of the complete CVIU and RT1553 electrical validation on a representative EM.
    • The qualification test sequence that will be performed on this PFM includes vibrations, thermal vacuum tests and EMC emission and susceptibility tests on Main Bus.

Current status

CVIU Module:

  • Design and development of the module are completed,
  • Manufacturing files are completed,
  • EM board tests are completed,
  • FM board tests are completed.

RT1553 Module:

  • Design and development of the module are completed,
  • Manufacturing files are completed,
  • EM board tests are completed,
  • FM board tests are completed.

CVIU and RT1553 FM modules have been integrated in an equipment (PLIU) and successfully qualified in a PLIU PFM during the 1st quarter of 2011.

Contacts

Status date

Wednesday, July 31, 2013 - 10:43