2.45 GHz Microplasma Technology at the FH Aachen · Holger Heuermann FH Aachen University of Applied Sciences Institute of Microwave and Plasma Technology 2.45 GHz Microplasma Technology

Holger Heuermann FH Aachen University of Applied Sciences Institute of Microwave and Plasma Technology

2.45 GHz Microplasma Technology at the FH Aachen

© FH AACHEN UNIVERSITY OF APPLIED SCIENCES 14. November 2016 | 2

Contents:

- Comparison: Laser / MW-Plasma

- Introduction Microplasma

- Technology to Generate Microplasmas

- Other Applications - Lamps - Jets and more

- 2.45GHz Spark Plugs

Overview

08.2006:

First microplasma spark plug

from the FH Aachen driven

with a magnetron with 600W


- First laser from 1960

- First hardware was very expensive

- 1980: Breakthrough with cheap semiconductor lasers

- Meanwhile in a lot of applications: e.g. DVD, laser printers,

pointer, cutting, welding, eye and shin treatment, spectroscopy

- In Europe: Maybe 5 lasers per household

Status Laser


- Arc discharge (or Corona discharge)

- Very long history and the first hardware was cheap

- Meanwhile very much applications: e.g. lamps, spark plugs,

plasma TV, welding, melting, jets for activation, coating and other industry processes

- In Europe: Maybe 30 plasma sources per household

Status Atmospheric Plasma


- Microplasma: Microwave driven plasma

- FH Aachen: large plasmas at 2.45 GHz driven with cheap

semiconductor technology

- In contrast to an arc plasma: Microplasmas does not need a ground electrode

- The plasma temperature is higher than the electrode temperature

- At higher pressure, plasma volume reduces as energy density increases

Introduction Microplasma

2010:

First microplasma jet from the

FH Aachen driven with a

transistor-circuit at 100W


Technology to Generate Microplasmas: Theory of High Voltage Generation

Simplified

electrical circuit

of the three stage

impedance transformer

Realization of the

impedance

transformation using

distributed elements

in coaxial technique


Technology to Generate Microplasmas Theory of High Voltage Generation

Input impedance Z0 = 50 Ω

Output impedance Zout ≈ 0.5 MΩ

This concept is based on a three stage transformation network. The

first and third transformation are realized by a gamma-transformer and

the second stage by an autotransformer.

The full mathematical derivation is

presented in other papers. The

results to calculate the elements are

given in the following equations:



All mechanical

components of

our first

microplasma

spark plug

Impedance

transformer

(in simple

form)



Reflection coefficient of the impedance transformator for ignition

Matching for ignition

Matching = 6 dB

(25% of the energy

is reflected)



Voltage = 10,000V

Calculated ignition voltage

Output voltage of the realized impedance transformator for ignition


Technology to Generate Microplasmas Theory of High Voltage Generation and Operation

Bi-static matching

Optimization for both states:

- Ignition (matching and high voltage)

- Operation of a microwave plasma (matching)

Frequency shift between the two stages:

- 40 MHz in the 2.45 GHz ISM-Band

40 MHz jump is only possible with semiconductors


Technology to Generate Microplasmas Microwave Generator and Control Loop

Block diagram

VCO

Low pass filter

Coupler 1 Coupler 2 Plasma

Detector 1 Detector 2

Difference

(~ S11)

Variable

DämpfungPA

Amplifier

external

Amplitude-

discriminator

MVG-IC

Inner circuit to control the bi-static matching in a control loop



RBW 1 MHz

VBW 1 MHz

SWT 5 ms

*

*

1 AP

CLRWR

A

Ref -10 dBm Att 0 dB*

Start 2.2 GHz Stop 2.7 GHz50 MHz/

SGL

PRN

-110

-100

-90

-80

-70

-60

-50

-40

-30

-20

-10

1

Marker 1 [T1 ]

-48.18 dBm

2.458000000 GHz

Date: 25.OCT.2010 09:29:22

SMD-realization to control our generators including automatical locked loop for bi-static matching (replaced by MVG-IC)

2.3 2.4 2.5 2.62.2 2.7

-8

-6

-4

-2

0

-10

2

freq, GHz

dB

(S(1

,1))

Readout

m2

2.462G-2.991

m3

2.453G-5.653

m4

m2freq=dB(S(1,1))=-2.973

2.440GHz

m3freq=dB(S(1,1))=-3.664

2.460GHz

m4freq=dB(S(1,1))=-5.959Min

2.450GHz



New circuit for 15W-application

Highly integrated generator electronic with LDMOS transistor for an

energy saver lamp, http://3ppbulb.com

MVG-IC

Pre-amplifier

Main-amplifier



Laboratory generator for ignition

Portable development environment to generator the microwave power

(up to 100W) and to monitor the matching during operation


Other Applications Lamps and more


Just presented on the Light and Building

Lamps for general lighting

First electrode-less low pressure discharge lamp called 3ppBulb

Mercury-

free!!


Just presented on the Light + Building: Beamer Lamp Future: low power

Actual research work at FH Aachen: 1.: 10W-lamps based on this beamer lamp for general lighting: 2016: lamps with best spectrum 2.: head lamps for car: Project with Osram, Hella, supported by NXP

Novel 120W single-sided beamer

lamp driven by an 2.45 GHz signal


Just presented on the Light + Building: Beamer Lamp Innerer Aufbau der ersten HF-Beamerlampe

Lg

Lt Ckoppel

50 - Zuleitung


Just presented on the Light + Building: Beamer Lamp Erster Aufbau HF-Beamerlampe (Diplomarbeit)


Just presented on the Light + Building: Beamer Lamp Ein Entwicklung der HF-Beamer-Lampe

9,9*1

19,1*1

45,3*2 48,9*257,2*2

0

10

20

30

40

50

60

70

80

2009 2010

lam

p e

ffic

acy

lm/W

50 W UHP

120 W PVIP

• Verbesserungen innerhalb des nur einjährigen Projektes

• Potential für 80 lm/W vorhanden

From Philips

From KIT

*1 Measured at Philips Research Aachen

*2 Measured at LTI Karlsruhe


Just presented on the Light + Building: Beamer Lamp Innerer Aufbau der ersten HF-Beamerlampe

Aktivitäten:

• Vertrieb dieser Beamer-HF-Lampen

• F+E-Projekt mit 2,5 Mitarbeitern über 3 Jahre:

Thema UHP-Lampen bis 35W

Eigenschaften Referenzlampe: Philips

TOP

120 W / 132 W 1.0

Mikroplasma-Lampe:

OSRAM PVIP

120 W / 132 W 1.0

modifiziert

Lichtstrom [lm] 7825 8521

Lampenleistung [W] 132 149

Lampeneffizienz [lm/W] 60,2 57,2

Leuchtdichte [Gcd/m2] 2,59 2,79

Farbwiedergabeindex Ra [%] 62,5 66,8

Anlaufzeit bei Kaltzündung

[s] 55 16

Wieder-Zündung nach

Betrieb [s] ca. 120 ca. 0 – 40


Future: Low Power High Pressure Lamps Arc attachments of microwave driven HID-lamps

• Diffuse MW-mode appears only in MW operation

• Low global tip temperature of the electrode

• Low electron emission of the electrode

Displacement current

• Spot-mode appears in MW and AC operation

• High local tip temperature of the electrode

• high electron emission of the electrode

Conduction current

MW @ 15W

MW @ 25W


Future: Low Power High Pressure Lamps „Electrode“ configurations for microwave operation

Capacitive coupling of the plasma arc:

Non-metal electrode/(-less)

High lifetime

Higher variety of the salts

Metal electrodes (tungsten)

Non-metal „electrodes“ (e.g. ceramic)

Electrode-less

Vessel (quartz or ceramic)

Plasma arc


Other Applications: Plasma Jets

FH Aachen research work microwave scalpel

Status > Patient on metall plane > Arc and current at 400W

Our project: > Jet similar to short range

laser > No current flow



Products of Heuermann HF-Technik GmbH:

Plasma jet with cannula for high power applications

Generator with 200W



Products of Heuermann HF-Technik GmbH:

Mini plasma jet with

10W for health

applications (in medical

qualification) and

activation


- Low emission heating (drives burner!)

- Clean air (hospitals, clean rooms)

- Ultrasonic up to the um-range for a lot of applications

- Welding, melting, ….

Other Applications: Many

The expensive part is

the power amplifier!


1. Generation Runs in a standard engine


Advantages of our spark plugs:

- Cheap and small electronic

- High voltage only in the spark plug

- Best plasma generation conditions by signal with a rise time of only 0.1 ns

- No electrode-material in the plasma – low wear

- Free in time of ignition

- Free in the number of ignitions

- Free in duration of ignition

1. Generation of 2.45GHz Spark Plugs

09.2006:

RF spark plug driven with 20W


Highest voltage only at the electrode


ca. 5,000,000 V/m

ca. 500 V/m


Test motor at the

Aachen University

of Applied

Sciences

This engine run

with our spark

plug!

1. Generation of 2.45GHz Spark Plugs Operation under atmosphere 2009

1. Generation of 2.45GHz Spark Plugs Operation under pressure

1bar 5bar 10bar

15bar 20bar 30bar (Filter)


2. Generation - Design Design of 2. Generation 2.45GHz Spark Plug


Novel inner construction

2. Generation of 2.45GHz Spark Plugs New design for higher pressure applications

Peek


Explosion view of the novel inner construction

2. Generation of 2.45GHz Spark Plugs Easy to manufacture

Peek


Cross section of the full spark plug

2. Generation of 2.45GHz Spark Plugs New design


Full finite element-model for simulation

2. Generation of 2.45GHz Spark Plugs Full finite element design: meshing


E Field

2. Generation of 2.45GHz Spark Plugs Electromagnetic results for the ignition

ca. 5,000,000 V/m


Matching S11

2. Generation of 2.45GHz Spark Plugs Results ignition

- 18 dB


E Field

2. Generation of 2.45GHz Spark Plugs Results operation

ca. 1,000,000 V/m


Matching S11


- 5 dB


2. Generation of 2.45GHz Spark Plugs Multi physic design: strength simulation

Numerical investigation of the spark plug ceramics with regard to strength at high-pressure conditions


Temperature simulation


294 °C







1830 °C




1830 °C


2. Generation – Hardware and first Tests 1. Tests of the New 2.45GHz Spark Plugs


2. Generation of 2.45GHz Spark Plugs First hardware of the second generation

Peak capacitor

Microwave spark plug out of 7 components

Measure-

ment

adaptor


Ground electrodes melted

2. Generation of 2.45GHz Spark Plugs First tests: 1. problem

Replaced by external electrodes


Series-C melted

2. Generation of 2.45GHz Spark Plugs First tests: 2. problem

Replacement is on-going: cost actual 50% performance in operation mode (reflected power is 50% of incident power)


2. Generation of 2.45GHz Spark Plugs First tests: under atmosphere

Sparks between center electrode and ground electrodes at ca. 50W-puls with <100mJ (target: 100W-puls with 400mJ)


2. Generation of 2.45GHz Spark Plugs First flow tube measurements at the IAV

IAV-flow tube for first charge motion test


2. Generation of 2.45GHz Spark Plugs First flow tube measurements at the IAV

Flow tube results for two views (pressure 1 bar)

Position 1

T = 1 ms / v = 0 m/s

T = 1 ms / v = 0 m/s

T = 1 ms / v = 25 m/s

T = 1 ms / v = 25 m/s

T = 5 ms / v = 25 m/s

T = 5 ms / v = 25 m/s

Position 2

Summary

- Introduction Microplasma

- Theory of High Voltage Generation

- Microwave Generator and Control Loop - Other Applications: Lamps, Jets und

much more

- 1. Spark Plug Generation with 2.45GHz Microplasma

- Design of 2. Spark Plug Generation with 2.45GHz Microplasma

- 1. Tests of 2. Spark Plug Generation

Thank you Have a good discussion

Documents

2.45 GHz Microplasma Technology at the FH Aachen · Holger Heuermann FH Aachen University of Applied Sciences Institute of Microwave and Plasma Technology 2.45 GHz Microplasma Technology