SLUAAS4 January   2024 LM5155-Q1 , LM51551-Q1 , LM5156-Q1 , LM51561-Q1 , LM51561H-Q1 , LM5156H-Q1 , LM5157-Q1 , LM51571-Q1 , LM5158-Q1 , LM51581-Q1 , UCC28700-Q1 , UCC28730-Q1 , UCC28740-Q1 , UCC28781-Q1 , UCC28C50-Q1 , UCC28C51-Q1 , UCC28C52-Q1 , UCC28C53-Q1 , UCC28C54-Q1 , UCC28C55-Q1 , UCC28C56H-Q1 , UCC28C56L-Q1 , UCC28C57H-Q1 , UCC28C57L-Q1 , UCC28C58-Q1 , UCC28C59-Q1

 

  1.   1
  2.   Abstract
  3. 1Introduction
    1. 1.1 Low-Voltage Isolated Bias Power Supply
    2. 1.2 High-Voltage Isolated Bias Power Supply
  4. 2Pre-Regulator Requirement
    1. 2.1 Pre-Regulator at Low-Voltage Battery
      1. 2.1.1 Single Pre-Regulators Architecture
      2. 2.1.2 Multiple Pre-Regulators Architecture
    2. 2.2 Pre-Regulator From High-Voltage Battery
  5. 3Fully-Distributed Architecture
  6. 4Semi-Distributed Architecture
  7. 5Centralized Architecture
  8. 6Redundancy in Isolated Bias Power Supply Architectures
    1. 6.1 No Redundancy
    2. 6.2 Redundancy to all Devices
    3. 6.3 Redundancy to Low Side Only
    4. 6.4 Redundancy to High Side Only
  9. 7Summary
  10. 8Terminology

3 Fully-Distributed Architecture

In a fully-distributed architecture of the traction inverter, each of the gate drivers is supplied by an individual isolated bias power supply device. That means for six gate drivers, six isolated bias supply devices are needed. Although this architecture is not necessarily a cost-effective option, using multiple power supply devices can help to increase the safety of the system.

GUID-20231228-SS0I-8NMM-LT94-MJL4DMVRNDR2-low.svgFigure 3-1 Fully-Distributed Architecture

Use of an integrated DC/DC transformer module can be the preferable choice for fully-distributed architecture. These integrated modules have an integrated transformer, which is switching at a very high frequency range of 11MHz to 15MHz. Using an integrated transformer module eliminates the need of external transformers, which results in a reduction in size and height of the overall system. Additionally, these integrated DC/DC modules need only few external discrete components, therefore this architecture is simpler from the design and layout perspective.

TI offers several variants of the integrated DC/DC modules. These variants give the flexibility to choose the appropriate device, based on the availability of the input voltage rail in the system and required output voltage. Figure 1-1 shows all variants and the technical specifications.

Table 3-1 Texas Instruments Integrated Transformer Designs
Part NumberIsolation StrengthVIN | VOUT NominalVIN RangeVOUT RangeTypical Power
UCC14240-Q1
UCC14241-Q1		Basic (3kVRMS)
Reinforced (5kVRMS)		24VIN | 25VOUT,21V–27V15V–25V2.0W
UCC14140-Q1
UCC14141-Q1		Basic (3kVRMS)
Reinforced (5kVRMS)		12VIN | 25VOUT10.8V–13.2V
8V–18V		15V–25V
15V–25V		1.5W
1.0W
UCC14340-Q1
UCC14341-Q1		Basic (3kVRMS)
Reinforced (5kVRMS)		15VIN | 25VOUT13.5V–16.5V15V–25V1.5W
UCC14130-Q1
UCC14131-Q1		Basic (3kVRMS)
Reinforced (5kVRMS)		12–15VIN |
12–15VOUT		12V–15V
10V–18V
15V–18V
14V–18V		12V–15V
10V–12V
15V–18V
10V - 18V		1.5W
1.0W
1.5W
1.0W
UCC15240-Q1
UCC15241-Q1		Basic (3kVRMS)
Reinforced (5kVRMS)		24VIN | 25VOUT21V–27V15V–25V2.5W

There are other topologies which can be used for a fully distributed type of architecture. Typical example of these topologies are LLC resonant, PSR-flyback (primary side regulated flyback) and push-pull. One of the advantages of these topologies is that have a capability to deliver more power compared to the integrated DC-DC modules. This is discussed in more detail in the next section.