-1 5 0
1 .0 0 .8
❖ 3 phase short-circuit duration
0 .6
0 .4 0 .2
100ms
1 .0
0 .5
0 .0
-0 .5
-1 .0
1 .0 8 1 .0 6 1 .0 4 1 .0 2 1 .0 0 0 .9 8
0
1
2
3
4
5
6
7
8
t/s
动态电压崩溃
Dynamic Voltage Callapse
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
The wind penetration is high
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 worldwideWhy do we need LVRT?
迟永宁 CHI Yongning 并网技术室 2009.01.06
中国电力科学研究院新能源研究所
大纲 Outline
1. 低电压穿越（LVRT）的概念
must be tripped in case of voltage dips during the grid fault.
风
桨叶
齿轮箱
异步发电机
低速轴 高速轴
升压变
电网
并联电容器组
1. 低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
P/M W
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。
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.
➢ LVRT is necessary.
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。
Voltage dips will be more severe during high wind penetration
4. 风电机组低电压穿越的实现方案
Realization of wind turbine LVRT
1、 低电压穿越（LVRT）的概念
Concept of Low Voltage Ride Through
1. 低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
➢ 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.
U
β
P M
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：
➢ 可以允许风电场在电网发生故障及扰动时切除，不会引起严 重后果。
The wind penetration is low
➢ The trip of wind farm (wind trubine) during power grid disturbances can be acceptable. It‘s not a big problem to the power system.
E
ω Q /M V a r r
200
100 0
❖ 150MW风电场，基于普通
-1 0 0
异步发电机的恒速风 .1
❖ 三 相短路故障持续 0.1s
1 .0
150 75
❖ Wind farm capacity 150MW.
0 -7 5
IG based wind turbines.
➢ 也有故障穿越的提法。FRT：Fault Ride Through
1. 低电压穿越（LVRT）的概念 Concept of Low Voltage Ride Through
由于风电机组一般采用异步发电机技术（丹麦概念），电网发 生故障时机端电压难以建立，若风电机组继续挂网运行，将会 影响到电网电压无法恢复，因此，电网发生故障出现电压跌落 时，一般都是采取切除风电机组的方法来处理。
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
1. Concept of Low Voltage Ride Through
2. 风电机组低电压穿越的必要性
2. The necessity of wind turbine’s LVRT
3. 各国风电标准对低电压穿越的要求
2. The requirement on LVRT in grid code worldwide