TIDUF55 November   2023

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Power Tree and Wakeup
      2. 2.2.2 Insulation Requirement for Isolated Interface
      3. 2.2.3 Robust Relay Driver
      4. 2.2.4 Stackable Daisy Chain Communication
    3. 2.3 Highlighted Products
      1. 2.3.1  TMDSCNCD263
      2. 2.3.2  LMR51440
      3. 2.3.3  TPS7A16
      4. 2.3.4  TPS7B81
      5. 2.3.5  TPS62913
      6. 2.3.6  TPS4H160-Q1
      7. 2.3.7  ULN2803C
      8. 2.3.8  ISO1042
      9. 2.3.9  UCC12050
      10. 2.3.10 ISO1410
      11. 2.3.11 SN6505B
      12. 2.3.12 BQ32002
      13. 2.3.13 HDC3020
      14. 2.3.14 TPS3823
      15. 2.3.15 DP83826E
      16. 2.3.16 TPS763
      17. 2.3.17 LM74701-Q1
  9. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware Requirements
    2. 3.2 Software Requirements
    3. 3.3 Test Setup
    4. 3.4 Test Results
      1. 3.4.1 Power Supply Testing
      2. 3.4.2 Daisy Chain Signal Quality
      3. 3.4.3 Relay Driving
      4. 3.4.4 Isolated CAN Transceiver Operation
  10. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Documentation Support
    4. 4.4 Support Resources
    5. 4.5 Trademarks
  11. 5About the Author

2.2.2 Insulation Requirement for Isolated Interface

Table 2-1 shows the insulation requirement in 1500-V BESS by the IEC 60664-1-2020.

Table 2-1 IEC 60664-1-2020 1500-V BESS Insulation Requirements
PARAMETER CLEARANCE CREEPAGE
Altitude Basic Reinforced Basic Reinforced
≤ 4000 m 7.1 mm 10.4 mm 8 mm 16 mm
5000 m 8.14 mm 11.84 mm 8 mm 16 mm

A basic insulation is required between the BCU and PCS or the BCU and BSMU. For an altitude of 4000 m, the minimum clearance is 7.1 mm and the creepage is 8 mm. For an altitude of 5000 m, the minimum clearance is 8.14 mm and the creepage is 8 mm. This design follows the requirement from an altitude of 4000 m. For CAN, UCC12050 and ISO1042DWV are used. For RS-485, transformer 750315371 and ISO1410DWR are used.

A reinforced insulation is required between the BCU and BMU. The minimum clearance is 10.4 mm and the creepage is 16 mm. To meet the minimum clearance and creepage requirements, a transformer for daisy chain or a digital isolator for CAN is necessary.

Consider using a more appropriate device or connecting the devices in series for altitudes above 4000 m.