TIDUEZ0A March   2021  – March 2022 TMS320F28P550SJ , TMS320F28P559SJ-Q1

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Three-Phase ANPC Inverter Architecture Overview
      2. 2.2.2 LCL Filter Design
      3. 2.2.3 Power Switching Devices Selection
      4. 2.2.4 GaN Power Stage
      5. 2.2.5 Voltage Sensing
      6. 2.2.6 Current Sensing
      7. 2.2.7 System Power Supplies
        1. 2.2.7.1 Isolated Bias Supplies
      8. 2.2.8 Si Gate Driver Circuit
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware and Software Requirements
      1. 3.1.1 Hardware
      2. 3.1.2 Software
    2. 3.2 Testing TIDA-010210 With AC Resistive Load
      1. 3.2.1 Test Setup
      2. 3.2.2 Experimental Results
    3. 3.3 Testing TIDA-010210 in PFC Operation
      1. 3.3.1 Test Setup
      2. 3.3.2 Experimental Results
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
      3. 4.1.3 Altium Project
      4. 4.1.4 Gerber Files
      5. 4.1.5 Assembly Drawings
    2. 4.2 Tools and Software
    3. 4.3 Support Resources
    4. 4.4 Trademarks
  10. 5About the Authors
  11. 6Revision History

3.3.2 Experimental Results

Close loop test output waveforms in Figure 3-6 show clean sinusoidal waveforms at the nominal load. During the experiments, no important zero crossing distortion was observed in the currents. Total harmonic distortion less than 4% was measured.



Figure 3-6 Currents and Voltage Working at 11-kVA PFC full

Table 3-1 and Table 3-2 collect the efficiencies of the PFC at 230 VRMS, respectively for two different DC bus voltages: 600 V and 800 V. The results obtained from the power analyzer are taken from 2 kW to 11 kW. In most of all the operating points, the power efficiency is higher than 98% by reaching a maximum of 98.62%.

Table 3-1 System Efficiency With GaN LMG3422R030 at 600-V DC
DC BUS VOLTAGE (V) AC GRID CURRENT (A) INPUT POWER (W) OUTPUT POWER (W) EFFICIENCY

605.3

3

2045.7

1980.2

96.8

605.34

5.22

3559.5

3506.1

98.5

605.38

7

4773.3

4707.4

98.62

605.2

8.9

6068.9

5978.5

98.51

605.28

10.9

7432.7

7309.3

98.34

605.34

13.05

8898.8

8731.5

98.12

605.5

15.2

10364.9

10148.3

97.91

605.8

16.5

11251.4

11006.1

97.82
Table 3-2 System Efficiency With GaN LMG3422R030 at 800-V DC
DC BUS VOLTAGE (V) AC GRID CURRENT (A) INPUT POWER (W) OUTPUT POWER (W) EFFICIENCY

803.4

3.02

2070

1976.8

95.5

801.4

5.24

3601.8

3511.8

97.5

802.4

7.01

4830

4747.9

98.3

803.4

8.95

6141

6042.7

98.4

803.5

10.93

7521

7408.2

98.5

802.8

12.98

8970

8826.5

98.4

803.8

15.21

10488

10304.5

98.25

803.1

16.52

11385

11180.1

98.2

All the data summarized in the tables have been collected and plotted as shown in Figure 3-7. At low power it is better to keep the PFC to work at lower DC bus voltage. Conversely, at a higher current keeping higher DC bus voltage leads an important efficiency improvement of 0.4%.

Figure 3-7 PFC Efficiency vs Input Power

The final design dimensions are outlined in Table 3-3 and show a total volume of 4.3 L. With a power rating of 11 kW, this results in a power density of 2.57 kW/L.

Table 3-3 TIDA-010210 Dimensions
AXIS DIMENSION
X 300 mm
Y 220 mm
Z 65 mm
Volume 4.29 liters