Microgrid harmonic detection

Which method is best for islanding detection of microgrid?

Load parameters play a great role to the effectiveness of the method. If the load is not resistance, the detection time and the NDZ will increase with higher value of Q. Therefore, AFD is the best for the islanding detection of microgrid which is just made up of resistive loads and without multiple inverters. 3.2.2. Frequency jump (FJ)

Does microgrid operate in grid-connected or islanding mode?

Microgrid may operate in grid-connected or islanding mode, running on quite different strategies. Effective islanding detection methods are indispensable to realize optimal operation of microgrid. In this paper, performance indices and critical technique problems are discussed. Islanding detection methods are also classified.

What happens if a microgrid is running on islanding condition?

When a microgrid is running on islanding condition, the current harmonics produced by the inverter are transmitted to the load and hysteresis effect of transformer will further aggravate harmonic distortion at PCC, which is able to detect islanding , , .

What is detecting time in a microgrid?

Detection time is the duration from the beginning of microgrid disconnecting from main grid to the end of detecting islanding by IDMs, which is defined as (4) Δ T = T I D M − T t r i p where Δ T is the run-on time, T I D M is the moment to detect islanding, and T t r i p is the moment microgrid disconnects from the grid. 2.3. Error detection ratio

What is the difference between passive and fast microgrid detection?

Detection time Fast detection is a premise for microgrid to have enough time to operate islanding strategy, assuring security and reliability. Passive methods are based on monitoring transient response of parameters including voltage and frequency. Their detection speed is faster than most active methods generally.

What is voltage and current Harmonics Detection (HD)?

Voltage and current harmonics detection (HD) This method is based on the measurement of total harmonic distortion (THD) at PCC to detect islanding when THD exceeds the threshold. Under normal conditions, when the microgrid is connected to main grid, PCC voltage is a standard sine wave, and thus load-generated harmonics are negligible.