1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
镇赉风电场一期（49.5MW） 洮北风电场（98.6MW） 宝山风电场（49.5MW） 洮南风电场(99MW) 富裕风电场(15MW) 镇赉变 大安变 查干浩特风电场 (24MW) 新立风电场 (49.5MW) 白城变 大安风电场(99MW)
2004-12-14
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
1
各国风电并网导则对低电压穿越的要求
－为什么需要低电压穿越
Comparison of LVRT requirements worldwide-
Why do we need LVRT?
Voltage dips will be more severe during high wind penetration
风电机组达到切入风速时 Low Wind
风电机组额定运行时 High Wind
10
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE

The impact on wind turbine of voltage dips

Unbanlance torque may influnce the stable operation of wind turbine Overcurrent of generator in transient may damage the Electronics components. Additional torque or forces may damage the mechanical components.
11
1.15
0.92
0.69
0.46
0.23
0.00 0.0
0.2
长 220: 电 (pu) 岭 压 洮 \220: 电 (pu) 南 压 前 \220: 电 (pu) 郭 压 松 \220: 电 (pu) 原 压 长 厂 山 \220: 电 (pu) 压
0.4
0.6
0.8
[s]
1.0
• 电网故障电压跌落曲线 • Voltage dips under power system disturbances
12
2004-12-14
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
DIgSILENT
12
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
系统中某节点电压跌落的严重程度与


此节点距离故障点的电气距离远近
此节点固有的无功电压支撑能力 风电功率的高低
密切相关

The voltage dip extent of specific busbar have closely related with

Electrical distance to the fault location Voltage support capability of the specific busbar Wind Power output
Concept of Low Voltage Ride Through
2. 风电机组低电压穿越的必要性
The necessity of wind turbine’s LVRT
3. 各国风电标准对低电压穿越的要求
The requirement on LVRT in grid code worldwide
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
4
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through

什么是低电压穿越？

LVRT：Low Voltage Ride Through 当电网故障或扰动引起风电场并网点的电压跌落时，在一定 电压跌落的范围内，风电机组能够不间断并网运行。
例
500kV线路 220kV线路 66kV线路
西郊 龙源长岭双龙风电场（49.5MW） 长岭风电场（99MW） 至双辽电厂
至正阳
至巨丰
至三家子
至梨树
2008 BaiCheng Power Grid Single Line Diagram
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
Induction machine is usally used in Denmark Concept Wind Turbines, the active exciting can not be provided by. The voltage can not be recovered if the wind turbine still keep operating so the wind turbine must be tripped in case of voltage dips during the grid fault.
Q/MVar

β
U
t/s
动态电压崩溃 Dynamic Voltage Callapse
7
PM
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
风电装机比例较低时：
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
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1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through


不同电网中对风电机组低电压穿越能力要求的高低也 不太一样。 The Low Voltage Ride Through Requirements to the wind turbines may different in different power grid.

The wind penetration is high


中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
9
1.

低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
高风电穿透功率情况下，故障导致的电压跌落更为严重。
Large scale wind farm ( wind turbine ) tripping will cause load flow changing violently even power system blackout. The frequecy stability issue is the most concern because the power losses could lead to instability. LVRT is necessary.
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
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2. 风电机组低电压穿越的必要性
The necessity of wind turbine’s LVRT
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
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2.
风电机组低电压穿越的必要性 The necessity of wind turbine’s LVRT
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
13
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
电网发生电压跌落对风电机组的影响


机械、电气功率的不平衡影响机组稳定运行 暂态过程导致发电机中出现过流，可能损坏器件 附加的转矩、应力可能损坏机械部分
0 1 2 3 4 5 6 7 8
150MW风电场，基于普通 异步发电机的恒速风电机组。 三 相短路故障持续 0.1s Wind farm capacity 150MW. IG based wind turbines. 3 phase short-circuit duration 100ms
ωr


The wind penetration is low

中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
8
1.
低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
风电装机比例较高时：



高风速期间，由于输电网故障引起的大量风电切除会导致系 统潮流的大幅变化甚至可能引起大面积的停电，而带来频率 的稳定问题。 低电压穿越能力是必需的
迟永宁 CHI Yongning chiyn@ 并网技术室
2009.01.06 中国电力科学研究院新能源研究所
2004-12-14
中国电力科学研究院
CHINA ELECTRIC POWER RESEARCH INSTITUTE
2
大纲 Outline
1. 低电压穿越（LVRT）的概念
Wind turbines should stay connected to the network and keep operation following voltage dips caused by short-circuit on any or all phases, where the voltage measured at the HV terminals of the grid connected transformer remains above the predefined voltage profile.