Current Mode Control Using IXC2. November 16, 2018

Transcription

1 Current Mode Control Using IXC2 November 16, 2018

2 High Growth Applications Applications in Data Center, Automotive, Automation, Renewables: 1. AC/DC - Power-Factor-Corrected- Bridgeless & Interleaved 2. DC/DC - LLC, Half-Bridge, Phase-Shifted Full-Bridge, etc. 3. Charging On-board (EV), Charge Stations, Off-grid 4. Inverters Bi-Directional, Automotive, UPS and Storage 5. Heavy Industrial Electrified Equipment, HVAC, Welding 2

3 Smart Power supply - 80 PLUS standards - ENERGY STAR - EN

4 D = V 0 V in

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6 L f ( 1/ fsw ) C f ( 1/ fsw ) L 2 N A l 0 C A d The need for high-voltage, high power density devices operating at high frequencies 6 and junction temperatures higher than 150 C is growing, especially for advanced power

7 Table 1. Physical properties for various semiconductors. Material E G, ev E C, MV/cm n i, cm -3 µ r, cm 2 /V/s v SAT, 10 7 cm/s σ T, W/m/K Si CTE, ppm/k GaAs x C-SiC H-SiC x H-SiC x GaN wurtzite x GaN zinc blende 3.2 Diamond x , r R SP ON BV n r E G R SP ON r 3 n BV 2 6 E G R SP ON BV r n E G 7

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12 ~22V ~340V PV Panel + 25 to 50V Buck Hysteritic Control 80 to 200 khz Solid State Transformer Unfolding Bridge + - 1:15 ~ - ~ + - Output Filter & Surge Protection Fixed Frequency 170kHz Figure 1 Block diagram of the 300 W low cost micro-inverter 12

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14 I REF max = 2 P out V Grid N T1 i REF (n) = I REF max sin 2πn 256 for n = I DAC_peak1 n = i REF n + I R n I DAC_trough n = i REF n I R n I R n = I RV Buck =0 + I Rmax I RV Buck =0 64 n 256f for n = 1 64 I R n = I Rmax + I Rmin I Rmax 64 n f for n = I R max, I Rmin, and I RV Buck =0 efficiency of the inverter. are tuned to obtain maximum

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17 Power supply The dement for PFC circuit is mainly driven by EN , ENERGY STAR and 80 PLUS standards. 17

18 PFC Definition of thee power factor, PF, of an AC electrical power system PF = P S real power apparent power PF = Displacement Factor Distortion Factor Displacement Factor = cosφ Distortion Factor = THD 2 THD = I 2 I I 3 I

19 Totem-pole bridgeless PFC converter. 19

20 PFC The positive half-line cycle equivalent boost circuit 20

21 PFC The negative half-line cycle equivalent boost circuit. 21

22 PFC Totem-pole bridgeless PFC converter. To improve the efficiency of the totem pole PFC synchronies rectification can be used. The converter operates as follow. Switch B 1 is ON, the current trough the inductor is rising. When the inductor current reaches peak value, the switch B 1 is turned OFF and after some delay, the switch B 2 is turned ON, the current trough the inductor is decreasing and when it reaches the trough value and after another delay, the switch B 1 is turned ON. During the two delays, the currents are passing through the switches intrinsic diodes and capacitors as it is explained above for no synchronous rectification. Dead time is necessary to avoid cross conduction! Using IXC2 event driven timers, the two delays can be changed dynamically during the operation and therefore the efficiency of the total pole PFC can be further improved

23 PFC 23

24 Agenda IXC2 HFCS2_LFCS2 and HFVS1 block diagrams 24

25 IXC2 Switching Engine 25

26 IXC2 Switching Engine configuration for Solantro Totem pole PFC 26

27 PFC Timing diagram of the Solantro Totem pole PFC Boost 1. 27

28 PFC 28

29 PFC Totem Pole PFC hardware and control loop for the low frequency switches t blmin = n min t n min THD, % V Grid > V bl and n n bl 29

30 contacting:

31 Thank you