new passive devices in power electronics -nice to have or a … · 2021. 1. 6. · new passive...

New Passive Devices in Power Electronics

-Nice to Have or a MUST?-

Dr. Petar J. GrbovićHuawei Technologies Düsseldorf GmbH

Nuremberg

Center of Power Electronics and Drives C-PED Lab.

Roma TRE Université, Rome, Italy

1. Motivation & the Facts

A. What we have been doing in last 70 years?

B. We do not need Inductors and Capacitors in Power Converters?

2. Key Issues We are Facing and what Do We need in future?

3. What else beside Magnetics and Capacitors

1. Drivers

2. Sensors

OUTLINE

-2-PCIM 2018, June 5-7, Nuremberg

Motivation & the Facts


New Power Converters

Extreme Efficiency

Extreme Power Density & Specific Power

Last 20 years, PCIM, PESC, ECCE…. Focus on New Power Devices only

…Motivation & Facts…


…….Today…


“Yesterday”: 10-15 years ago

Eff. 96%...Very Good Converter

“Today”: Eff. >99%... Can we go beyond?

It looks like Magnetics and Capacitors are now a Bottleneck .

Why we did not invest more in Magnetics and Caps?

A. History of Power Converters

B. Our Perception…Move faster & all our problems are solved

…Motivation & Facts…


History of Power Converters


Long time ago, static power conversion was simple and “primitive”….no yet power electronics

Long time ago…Yesterday…



…Development of Power Converters…


Heinrich Hertz's oscillator, 1887…

“Static “ Resonant Power Converter

Electromechanical switch



Tesla’s high frequency high voltage transformers for wireless power transmission, 1890s

Multi-resonant Static Converter


Very first controlled power converter was mercury arc rectifier developed in 1902 by Peter Cooper Hewitt.

Mercury-arc valve

Siemens 560V 1300A Mercury-arc valve

GE hydrogen thyratron for radar applications



Very first controlled power converter was mercury arc rectifier developed in 1902 by Peter Cooper Hewitt.

General Electric Company and engineer Alexanderson developed first controlled inverter to drive a three-phase motor in 1934



The Key Question was not: How efficient and small the Converter is?

The Key Question was: Does it work and if does for how long it will work?



1947, Shockley invented BJT 1947…. Nobel Prize in Physics (1956)

1956, First silicon controlled rectifier (SCR)

A replica of the first bipolar transistor High power SCR





The Key Question was not: How efficient and small the Converter is?

The Key Question was: Does it work and if does for how long it will work?

From 1950s to 1980s SCR, Power BJT and Power MOSFET

That was time to start thinking about new magnetics…but not much



Invention of Insulated Gate Bipolar Transistor-IGBT at the end of 1970s and begin of 1980s

The IGBT solved all the problems of BJT and MOSFET

What about magnetics and caps?



Super-Junction Si MOSFET invented in 1990s.

CoolMOS

MDmesh™

Magnetics & Caps are more & more critical, but not in focus yet!



End of 20 century, fresh blood is in the game SiC SBD, SiC JFET, SiC MOSFET, GaN HEMT

Again, the focus is only on devices, not on Magnetics & Caps!



Today, thanks to introduction of the IGBT and the SJ-MOSFET, power electronics is part of our life

Home appliance, audio/video, communication…..

Industrial Applications….

Transportation…

Wherever we need to control power flow without (significant) losses, we have to use power electronics.....

Invention of the IGBT has contribution of >20 trillion (1012) US$ to global economy due to energy saving!

…….Today…


…….Today…


Today, Even politicians are talking about Power Devices

…….Today…



…….Today…



But, did you see any politician talking about Magnetics & Capacitors?

…….Today…


Even politicians are talking about WBG Devices

But, did you see any politician talking about Magnetics & Capacitors?

...Do we need Passives?…

-Our Perception-


…Do we need Passives?…


The Main “Four Elements” of a power converter

1) A Matrix of Switches (Power Semi…)

2) A bunch of Inductors, Transformers and Capacitors (and Resistors )

3) Control Circuitry

4) Central Control Intelligence (S/W)



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Modulation Index m

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ConclusionA. Our dream to use Very Fast Switching Device

(VFSD) & eliminate passives is just a dream & it will stay a dream,





B. Using VFSD may open another issues

Inductor is not just an inductor





B. Using VFSD may open another issues

Inductor is not just an inductor

Capacitor is not just a capacitor

...What do we need for future R&D…


…Tomorrow…

Major objective of future R&D

A. Cost, Cost, Cost, Cost….

B. Size, weight and footprint….

C. Losses…

a) Energy saving

b) Cooling effort=Size, weight & Cost

D. But, Some times reliability and only reliability….

a) Fault tolerance….


…Tomorrow…

The Main “Four Elements” of a power converter

1) A Matrix of Power Semiconductor Switches

2) A bunch of Inductors, Transformers and Capacitors (and Resistors )

3) Control Circuitry

4) Central Control Intelligence


1) What is a power semiconductor?

And, what it would be in the future?

-37-

…Tomorrow…

PCIM 2018, June 5-7, Nuremberg

1) What is a power semiconductor?

From material perspective!

A power semiconductor is just a piece of roasted sand

27.7% of the planet is silicon!!

-38-

…Tomorrow…


-39-

…Tomorrow…


2) What about inductors and transformers?

Very costly and dirty technology!

Limited resources!

Today and it will be even worst tomorrow?

3) Control Circuitry is also Si?

Today and will be tomorrow?

4) Central Control Intelligence is just certain number of lines of C code?

When you have it, does not cost anything?

But you need to have it, and it costs ?

-40-

…Tomorrow…


Passives and Mechanical are dominant factors in the converter cost & size

-41-

…Tomorrow…


In future, we MUST use more and more Si, SiC, GaN...

More intelligence…

Less and Less iron and copper (Passives)

BUT, We cannot eliminated Magnetics & Capacitors

-42-

…Tomorrow…


-43-

… Magnetics …


...Magnetics…

Magnetic materials are progressing slowly

1. Ribbon based material (Amorphous and Nanocristallyn)

High saturation B and relatively low loses

A. What material in range 15kHz to 40kHz, especially at high ac flux density?


...Magnetics…

A. What material in range 15kHz to 40kHz, especially at high ac flux density?

Ribbon based core material (Amorphous and Nanocrystallyne)

Relatively High losses!!!

Ferrite

Low saturation B Big core!!!

Iron-Powders (Koll Mµ, MPP, High Flux, XFlux, Sendust,….)

High losses!

What Else??


...Magnetics…

A. What is the material in range 15kHz to 30kHz, especially at high ac flux density?

B. What about acoustic noise?



C. What about orthogonal flux & losses?

The flux flow is not well controlled

High leakage inductance transformers and ICTs

Significant additional losses in the lamination!!

-48-

B. Cougo and J. Kolar, “Integration of Leakage Inductance in Tape Wound Core Transformers for Dual Active Bridge Converters”, Proceedings of the International Conference of Integrated Power Electronics Systems (CIPS 2012), Nuremberg, Germany, March 6-8, 2012


...Magnetics…




D. What is material in Very High Frequency range?


Prof. Kolar CIPS 2014

...Magnetics…


...Magnetics…





Key direction for future high level integration

High power density but @ high efficiency

Isolated dc-dc, 170kW/L, extraordinary density!!

The key issue: Magnetics material and the transformer design





E. What is material in Ultra High Frequency range?

Most likely air-core magnetics


...Magnetics…

27.12MHz Converter (MIT & Stanford University)

Conclusion

A. New Core Material is a MUST?

For VHF

But also for MF and HF

B. New Material is not enough; New Geometry is also required

The Core To control of the flux distribution

The Windings To control of the winding capacitance


...Magnetics…

-53-

… Capacitors …


...Power Capacitors…

Also, not progressing well

A. Electrolytic Capacitors,

Old Good Boys, Invented in 1920s (Samuel Ruben, William Dubilier……)

We do not like E-Caps because….life time….our perception !!


>50,000h if the converter is properly designed

Is this really bad as we believe ?




Old Good Boys, Invented in 1920s (Samuel Ruben, William Dubilier……)

We do not like E-Caps because.…life time….our perception !!

In some applications E-Caps are not very desired (PV Inverters)

In some applications E-Caps are Must (Single phase converters)


>50,000h if the converter is properly designed

Is this really bad as we believe ?




B. Film Capacitors,

Energy density

Current capability [A/µF] is much better than E-Caps, but still not enough





B. Film Capacitors,

A. MLCC Capacitors (Dielectric X6S, X7T, C0G)

Energy density better than Film Capacitors but not good enough

Good Current Capability

ESR = 1(f)




A. Electrolytic capacitors,

B. Film capacitors,

A. MLCC capacitors (Dielectric X6S, X7T, C0G)

Energy density better than Film Capacitors but not good enough

Good Current Capability

ESR = 1(f)

C=2 (Uc)


...Power Capacitors…Something New

EPCOS CeraLink™ Capacitors – The revolution for fast switching inverters Antiferroelectric capacitor technology


High Current Capability High Capacitance at Operating Voltage

1µF 500V

EPCOS AG 2015

...Power Capacitors…What We Need?

Very high current capability @ moderate capacitance is required for resonant and switched capacitor converters


I. “Profi” Portable Welding Supply

500A 40V

98% Efficiency

2kW/kg

II. “HV”DC Date Center Power Supply

54V 200A

98.5% Efficiency

3kW/kgSeries Resonant Converter (SRC)



I. Energy Storage Interface DC/DC Converter

15kW (Si Only, No WBG)

99.5%

25kW/kg & 50kW/dm3

Partial Power Rated Converter (PPRC)




23uF /100A @100kHz


I. 20kW SRC: 10-20µF, 450V & 30A RMS (1.5-3 A/µF)

II. 100 kW PPR converter: 20-40µF, 450V & 160A RMS (4-8 A/µF)


Conclusions


• up to 10A/µF @ 600V



Conclusions


• up to 10A/µF @ 600V

E-Caps will stay in the game for while, But significantly higher capacitance density, current capability and life time at low frequency are a MUST

Competing with Active Caps, but this is not economical



Conclusions


• up to 10A/µF @ 600V

E-Caps will stay in the game for while, But significantly higher capacitance density, current capability and life time at low frequency are a MUST

Competing with Active Caps, but this is not economical

MLCC

Better C(U) characteristic

Low ESR @ LF


-66-

… Gate Drivers & Aux…


Multi-Cell & Multi-level Conversion will solve all our issues….or may be not….

120V OptiMOS for 3 phase 400V system

Very low losses

Very popular and low cost device

How many devices we need per a system?

I. 2x10=20 per phase and cell

II. 2 cells & 3 phases 120 devices per a converter

III. Back to back Config. 240 Devices per a system


...Gate Drivers…


I. PULSE WIDTH MODULATOR

Device=1 PWM

1 Converter =120 PWMs

Traditionally DSC TMS 335/337

Max 24 PWMs

DSC is not an Option

...Gate Drivers…


I. PULSE WIDTH MODULATOR

Device=1 PWM

1 Converter =120 PWMs

Traditionally DSC TMS 335/337

Max 24 PWMs

DSC is not an Option

Only Option is an FPGA or a CPLD

...Gate Drivers…


FPGA does not likedirect connection topower device

II. INTERFACE: CONTROL POWER

...Gate Drivers…



A Link between is aMUST

a) Iso.. Gate Driver,

b) Iso.. Power Supply

Today it is state of theart??

...Gate Drivers…



A Link between is aMUST

a) Iso.. Gate Driver,

b) Iso.. Power Supply

Today it is state of theart??

1 Device 1 GD+PS $$$$

>10% of total BOM cost

...Gate Drivers…


Today

Tomorrow

...Gate Drivers…


Integrated Gate Driver Circuit & Power Supply

Transfer power and signal using same transmission device

>20MHz carrier

Up to 500mW power

Very challenging, requires very advanced manufacturing capability

...Gate Drivers…


...Conclusions…

• Whatever we do, we need Passives

• Using VSFD does not mean we will eliminate Passives, we may open new issues

• Magnetics

• We need Better Core material

• We need Better Design

• Capacitors

• Better Energy Density…E-Caps, MLCC

• Much Higher Current Capability

• MLCC Better ESR(f) & C(f)

• Gate Drivers & Current Sensors

• Integration

Thank You Very Much for Your Time

[email protected]


new passive devices in power electronics -nice to have or a … · 2021. 1. 6. · new passive...

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