徐隆亚教授报告下载

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Transcript 徐隆亚教授报告下载

Dr. Longya Xu
Center for High Performance Power Electronics
The Ohio State University
一、引言
二、SiC和GaN功率器件特点
三、SiC和GaN功率器件技术发展现状
四、 基于SiC和GaN功率器件的最优拓扑
五、研究内容及未来电网应用
第一代半导体功率器件
以Si双极型(BJT)功率晶体管为代表
向大功
率、和
高效,高
第二代半导体功率器件
以Si场效应晶体管和IGBT为代表
频方向
发展
第三代半导体功率器件
以SiC场效应功率晶体管和
GaN高电子迁移功率晶体管
为代表
人们寄希望于
宽禁带半导体
功率器件来解
决第一代、第
二代功率器件
的输出功率低、
效率较低和工
作频率有限等
方面的问题
SiC 和 GaN 由 于 独 特 晶 体 结 构 , 其 禁 带 宽 度 达 到
2.2eV(3C-SiC),3.3eV(4H-SiC)和3.4eV(GaN),远高于
GaAs(1.4eV)和Si(1.1eV),它们具备以下特点:
• 工作温度很高,理论值结温可达600℃,从而器件的冷却系
统可大为简化。
• 热导率高, SiC达4.9W/cm℃, (Si为1.4),优势明显;SiC热
导率远远高于大多数半导体,室温时几乎高于所有金属.
• 硬度高于GaAs和Si,SiC达到9级,仅次于金刚石;便于器
件实施高密度、大功率集成。
• 电 子 饱 和 漂 移 速 度 高 , 达 到 2x107cm/s(SiC) 和
2.5x107cm/s(GaN),适于高频工作。
• 击穿电场高达2x106V/cm(4H-SiC) 和3.3x106V/cm(GaN)为
Si的8倍和10倍,能够实现高工作电压。
• AlGaN/GaN异质结二维电子气浓度高(2X1013/cm2),
SiC的掺杂浓度可达1019/cm3,能够实现高电流密度。
• 本征载流子浓度低,(4H-SiC为8.2x10-9cm-3 ,GaN为
1.9X10-10cm-3),便于管芯隔离。
• 抗辐照能力比GaAs和Si强~2个数量级,另外开关损耗
低1~2个数量级。
SiC and GaN BASED POWER ELECTRONICS
• + 50 to 75 0 C operating temperature
• 2-4X in power density
• 1-5% increase in conversion efficiency
从20世纪90年代起,美国国防部就开始支持
(>$300M) SiC功率器件研究。
21世纪初,美国国防先进研究计划局(DARPA)启动的
宽禁带半导体技术计划(WBGSTI - widebandgap
semiconductor technology initiative ),成为加速
和改善SiC和GaN等宽禁带材料和器件特性的重要“催
化剂” 。
• Significant Government investment has yielded near defect-free wafers
• Defects (limits yields/performance) now at acceptable levels from multiple suppliers
Median Micropipe Density, cm-2
• Evolution to 4” wafers significantly impacts $/amp cost (77% more die/wafer)
200
100
100 mm
3-inch
50
20
10
5
2
1
2001
2002
2003
2004
Year
2003
2006
2007
• SiC diodes available since 2001. Price, performance/demand have improved metrics.
• 2009 commercialization of switches - dramatic increase in potential SiC applications.
Cree SiC JBS Diode Mega-Amps Shipped Per Quarter
> 2x Reduction in Price of SiC Diode
– Higher Quality Wafers
– Larger Production Volumes
– Increase Wafer Size
10.0
Q3-FY08 11.3 Mega-Amps Shipped
8.0
6.0
JBS = Junction Barrier Schottke
4.0
0.45
2.0
0.4
0.35
0.3
Q
1F
Y0
5
2F
Y0
5
Q
3F
Y0
5
Q
4F
Y0
5
Q
1F
Y0
6
Q
2F
Y0
6
Q
3F
Y0
6
Q
4F
Y0
6
Q
1F
Y0
7
Q
2F
Y0
7
Q
3F
Y0
7
Q
4F
Y0
7
Q
1F
Y0
8
Q
2
FY
08
Q
3
FY
08
-
0.25
$/Amp
Quarter (Fiscal Year)
0.2
08
3Q
08
1Q
07
3Q
07
1Q
06
3Q
06
0
1Q
5A, 10A & 20A
0.05
05
1200V
0.1
3Q
1A, 2A, 4A, 6A, 8A,
10A, 20A
0.15
05
600V
1Q
Q
SiC JBS Diode Mega-Amps
Shipped/Quarter
12.0
• SiC diodes and switches are highly potential in many applications;
• SiC based power electronics is an enabling technology for electrifications
• Majority of power applications require
switch + diode.
• Power supplies
• Motor drives
• Inverters
• Switches are now available
• Continued “electrification” + renewed
focus on energy independence + conservation will accelerate demand for SiC
Source: Yole’ Development Market Research Report
Power Supply Benefits
HEV Electrical Subsystems
Large SiC Emerging Market:
- Diodes reduces motor losses up to 30%
• Area reduced 38%
• Weight reduced 44%
• Power density up 61%
- Diodes + MOSFETs reduce losses >50%
- Liquid cooling system eliminated;
dropping wt & system cost
- Projected fuel efficiency gain - 5-15%
Honda – 680V, 200A SiC MOSFET inverters-> 46% loss reduction
Nissan – SiC hetero-junction diode inverter-> 50% loss reduction
现有的SiC 功率器件技术数据
传统的电力电子拓扑
输入端口
集中的
多电力电
子器件
开关矩阵
集中的
大容量LC
储能元件
集中的
多电力电
子器件
开关矩阵
输出端口
适宜于SiC和GaN 器件的最优拓扑
一种可能的拓扑 – 开关电容元
例子: 电容开关子电路
- 模块性 分散性拓扑
LS1
LS2
S1
S3
C2
C1
S2
S4
LS3
LS4
S5
S7
C4
C3
DC
CIN
1
RLOAD
S8
S6
2
C6
LS6
LS5
S9
S11
C8
C7
S10
3
By utilizing the
new topology,
the power loss
on the
input capacitor is
reduced to 3.1%
of its original
value .
The output
voltage ripple is
reduced to 11%
of the
original value .
S12
Voltage Quadrupler DC/DC stage
1
2
LS1
C2
S7
LS2
S1
S4
S2
C1
S5
S9
VIN
S8
S3
-
S6
S10
VOUT +
L
RLOAD
Voltage doubler based dc/ac stage.
Experimental Development Results
Photovoltaic Micro-Inverter without Inductor
and Transformer
五、研究内容及未来电网应用
经过20多年的发展,在降低电力设备体积和
成本以及提高效率等方面,电力电子技术已经
成为主要手段。在电力输配电系统中,电力电
子技术在效率和成本方面能够完成传统技术所
不能提供的技术支持。在未来电网发展中电力
电子技术将发挥越来越重要的作用。
DC的产生形成了最初的电力系统,并且可以
认为是最自然的电力形态。AC系统出现是因为变
压器提供了一种相对简单的可在不同等级之间变
换电压的方法,以适应电力系统的要求。
基于碳化硅的HVDC和FACTS技术应用到输电
和配电系统后,将对电力系统智能化产生巨大的影
响。将以高智能方式, 在高性能, 低成本、高效率和
小体积等方面对传统的AC技术发起挑战。
适用于宽能带电力电子器件的新型拓扑
宽禁带电力电子器件驱动技术
宽禁带半导体器件环境适应性验证技术
宽禁带半导体器件在电力系统中的新应用
1。扣装式(clamp-on)微型传输线串联补偿器
微型传输线串联补偿器 – 原理图
微型传输线串联补偿器 – 效果
2 半导体固态电路变压器
2.1 传统式变压器
2.2 半导体固态电路变压器
Silicon Carbide (SiC) Power Semiconductors
Enabling The Future “More Electric” Economy
- DOE goal of 20% wind power
- NREL/SR-500-38515 2% eff
increase
$18B/yr US fuel cost savings
- Minimize active cooling
- Increase effective generator
rating to 1.0 from 0.5
High Temperature
High
Efficiency
- US Solar Connected ~24
GW by 2015
- All solar is connected to
grid via power electronics
High
Frequency
100-300 lb savings
- Replace 60Hz utility transformers
with high frequency
- 4X reduction in radar power
supply weight
- Minimize active cooling
- Enables single cooling loop
- Improves range by 3%
1.
DoE the first workshop of "Wide Bandgap Semiconductors in Clean Energy".
Workshop is in Chicago on July 25th
WBG semiconductors operate at temperatures above 150 oC without
external cooling, have longer lifetimes at higher operating voltages, and
switch at higher frequencies with fewer power. In the same way that the
invention of the silicon chip 50 years ago led to the development of the
modern computer and today’s electronics industry, WBG semiconductors
such as silicon carbide (SiC) and gallium nitride (GaN), as well as zinc oxide
(ZnO) and diamond (C), offer a similar opportunity to revolutionize the next
generation of microelectronics and clean energy innovations.
2.
IEEE Workshop on Applications of Wide-band-gap Power Devices
Topics include :
Material growth and device fabrication,
High power applications of SiC device
Approximate date of the workshop:
Middle October of 2013
WBD circuit topologies
Renewable energy and transportation
Location:
The Ohio State University