GB/T 47378-2026High voltage safety design criteria for space stations (English PDF)

5.1 Components and Sub-assemblies

5.1.1 Selection and Use The selection and usage requirements are as follows:

a) J599 round large contact electrical connectors should be preferred. If other types of electrical connectors are used, they should meet the requirements for low-pressure media. The withstand voltage should not be less than

2.5 times the operating voltage;

b) For multiple high-voltage electrical connectors on the same equipment, different models of electrical connectors should be selected or a misoperation prevention design should be adopted;

c) All electrical connectors for power transmission should be pin-type connectors with a socket for power supply and a pin for power receiving.

d) When using power MOSFETs, consider the effects of lead inductance, load parasitic inductance, or unrepressed circuitry when the load releases its stored energy. Avalanche breakdown caused by small inductance;

e) When selecting the power rating of a DC/DC converter, the principle of backward compatibility should be met, and derating requirements should be satisfied as much as possible. Choose products whose actual power consumption is close to their rated power;

f) DC/DC converters used in parallel should be from the same manufacturer and of the same specifications, and should be used in accordance with product requirements;

g) The DC/DC converter should have the function of protecting the input power bus.

5.1.2 Safety Distances and Isolation The safety distance and isolation requirements are as follows:

a) High-voltage power connectors should not be used interchangeably with other low-voltage connectors. If it is necessary to use different connectors, the arrangement of the connector contacts should be considered. Designed in zones to meet spacing requirements;

b) The positive and negative power supply lines of the same electrical connector should be designed in separate areas for contact allocation, and the positive and negative power supply lines should be... Maintain at least one contact interval;

c) The control signals of the solid-state power controller should be electrically isolated from the main power circuit;

d) When high-voltage and low-voltage lines are on the same printed circuit board, the high-voltage and low-voltage lines should be separated by area, and the number of lines should be reduced as much as possible. The length of the boundary between adjacent high-voltage and low-voltage lines;

5.2 Power supply and distribution equipment

5.2.1 Solar Cell fins The requirements for solar cell wings are as follows:

a) The power supply cables on the solar cell fins should use double-insulated wires;

b) The potential difference between adjacent battery strings should be less than 50V;

c) The current limit for each isolated solar cell string circuit should be less than 1.6A;

d) The insulation resistance between the solar cell substrate and the solar cell circuit should be greater than 10MOmega (DC250V), and the insulation resistance between the solar cell fins and the hull should also be greater than 10MOmega (DC250V). The connection should be grounded with high resistance, with a grounding resistance of 10kOmega to 100kOmega.

e) Isolated metal conductors with an area greater than 1 cm^2 in the solar cell array should be grounded;

f) The output terminal of the solar array circuit corresponding to each shunt regulation circuit should be isolated from the bus by a diode connected in series, and an open-circuit protection mechanism should be adopted. Effective measures;

g) The spacing between solar cell strings shall not be less than

5.2.2 Drive Mechanism The drive mechanism is required to transfer power from the external battery wings to the cabin, with the following requirements.

a) High-resistance grounding measures should be taken for areas where slip rings are not used;

b) The insulation layer thickness between adjacent power slip rings of the same voltage should not be less than

0.7 mm, and the creepage distance between adjacent power slip rings is generally greater than [missing value]. 3.2mm;

c) The insulation layer thickness of adjacent power slip ring components with voltage differences should not be less than 1mm;

d) The spacing between positive and negative slip rings should be no less than twice the thickness of the insulation layer between adjacent slip rings with the same voltage.

5.3 High Voltage Interface and Transmission

5.3.1 High-voltage power supply and distribution interface The requirements for high-voltage power supply and distribution interfaces are as follows:

a) Electrical isolation design should be implemented between different high-voltage power supply busbars;

b) Voltage and current monitoring devices should be installed at the power supply and distribution interface to measure voltage and current parameters in a timely manner and report the measurement results. Transmitted to the relevant display system;

c) A capacitor array with sufficient capacity should be provided at the high-voltage power supply output terminal. The capacitors should be connected in series or parallel, or connected in series with fuses, to ensure safety. Complete, to prevent short circuits in the capacitor from causing short circuits in the power supply;

d) Voltage measurement points for bus voltage acquisition and closed-loop voltage control should be located nearby, and protective resistors should be installed at the acquisition points;

e) The power supply contacts at the interface should be configured with separate positive and negative contacts, and the distance between the positive and negative contacts of the connector should not be less than 2.5mm;

f) The dynamic range of load changes at the power supply and distribution interface and the corresponding transient characteristics of the bus voltage, under normal and fault conditions. The voltage and current range values at the power supply and distribution interfaces should be clearly specified in the dedicated technical documents.

5.3.2 High-voltage bus transmission The requirements for high-voltage bus transmission are as follows:

a) High-voltage cables should use double-insulated conductors;

b) High-voltage cables should be installed separately in locations inaccessible to personnel, and isolated from low-voltage cables as much as possible; if there are local... If the parts intersect, the intersecting parts should be tied separately;

c) To prevent the concentration of heat effects in the layout of high-voltage cables, heat-generating components (such as shunts, discharge regulators, battery packs, and high-current cables) should be protected. (etc.) should be distributed in a decentralized manner;

d) When laying high-voltage cables, secondary isolation measures should be adopted along the transmission path, especially at the direct contact points between the high-voltage cables and the metal structure of the cabin. When laying insulation material, the width of the insulation material should be no less than 2 to 3 times the diameter of the cable.

5.3.3 Security of power distribution and electrical equipment interfaces The security requirements for interfaces between power distribution and electrical equipment are as follows:

a) The voltage and current ranges at the interface between the power distribution and electrical equipment should be clearly defined under normal operating and fault conditions;

5.4 High-voltage safety design relevant to astronauts

5.4.1 High-voltage design for astronaut activity area The high-voltage design requirements for the astronaut activity area are as follows:

a) High-voltage equipment should be located away from astronaut activity areas;

b) High-voltage equipment located near the astronauts' activity area should have insulation measures to prevent astronauts from being electrocuted;

c) High-voltage cables in the astronaut activity area should be bundled with orange strapping.

5.4.2 High-voltage safety design for on-orbit maintenance operations In addition to meeting the requirements of Chapter 4(a), the on-orbit maintenance high-voltage safety design should also meet the following requirements.

a) When repairing equipment related to solar cell wings, the repair manual should include information on safety design and protective measures.

b) High-voltage wire plugs (sockets) and high-current wiring that need to be disconnected for maintenance should be designed with insulating and short-circuit-proof protective sleeves;

c) Equipment or capacitors with high-voltage circuits should have means of energy discharge, and the corresponding operating procedures should be clearly defined in the maintenance process design. Process and high-pressure prevention measures;

d) Energy storage battery modules that require on-orbit operation by astronauts should be equipped with disconnect switches to ensure that the voltage remains below 36V for safety during astronaut operation. Voltage;

e) When astronauts operate high-voltage equipment that cannot be powered off, they should wear insulating gloves.

5.4.3 High-voltage safety design for extravehicular activities Before astronauts conduct extravehicular activities (EVAs), the surface potential of the space station should be reduced to below 36V. Simultaneously, during the EVA, the surface of the space station should be monitored. The potential is continuously monitored.

5.4.4 Safety signs The design and use of space station safety-related signs shall be carried out in accordance with the provisions of the dedicated technical documents for manned spacecraft using a high-voltage power supply system. High voltage warning signs should be installed at the power supply and distribution interfaces of power supply and distribution equipment.

5.5 High-voltage safety design for test/experiment loads

5.5.1 Power supply bus isolation The isolation requirements for the power supply bus are as follows:

a) For the A bus and B bus that provide 100V power from the space station to the payload, the payload should ensure electrical isolation between the different power supply buses. The isolation resistance is generally not less than 10MOmega;

b) The load equipment should ensure that the power supply line of the platform used is electrically isolated from the power supply line after voltage transformation inside the equipment. The resistance is generally not less than 1MOmega;

c) Protective measures should be taken for the load equipment, and overcurrent faults in the load equipment should not affect the power distribution equipment on the upstream platform;

d) When connecting the power supply connector to the load equipment, the load should be in an unloaded state;

e) For loads supplied by external adapters, the power supply from the robotic arm to the load shall be electrically isolated from the power supply from the adapter to the load.

5.5.2 Power Supply Link Design The power supply link design requirements are as follows:

a) The power supply cable should use double-insulated wires;

b) Secondary insulation measures should be taken for any points along the power supply cable laying path that may come into contact with the power supply cable;

c) For power cables that may move during on-orbit use, secondary insulation measures should be taken to prevent the cables from being damaged by long-term use. Worn out;

d) The structure of the space station should not be used as a primary power return line for electrical equipment.

5.5.3 Requirements for Ensuring High Voltage Safety During Production The following are the requirements for ensuring high-voltage safety during the production process of this product.

a) The minimum distance between exposed parts of the power supply busbar routing path and the surrounding area should not be less than 2.5mm, or protective measures should be taken;

b) The minimum distance between metal-cased components and other components, metal structural parts, and fasteners should not be less than