Ground of photovoltaic power station ground fault series rapid determination methods?

On the ground common solar photovoltaic power station group of ground fault, a rapid and practical methods are put forward. Ground photovoltaic power station; Set series of ground fault; The ruling. The cause of ground photovoltaic power station group series of ground fault generally has three kinds: 1) Set in the string

for photovoltaic power station photovoltaic series common ground fault on the ground, this paper proposes a fast and practical judgment method. Ground photovoltaic power station; Group of ground fault; Judgment. Surface photovoltaic power station group of bunch of ground fault generally for three reasons: 1) Due to the damage of the insulation layer, group of connecting with a string of a component in the bracket connected; 2) Set of components in series connection special-purpose plug ( MC4) Sealed with stent after rain enters the connected; 3) Connected to the photovoltaic controller of buried cable insulation damage. Group of tandem ground fault phenomenon in the event of a group of bunch of ground fault photovoltaic controller immediately issued a fault alarm and stop running; Stop working at the same time, frequency converter and inverter DC power distribution cabinet of DC circuit breaker tripping. Judging a group of judge fault photovoltaic controller series method of ground fault in the irradiance is 1000 W/m2, the environment temperature is 25 ℃ condition, shut off the inverter DC power distribution are measured by multimeter ark each photovoltaic controller of positive and negative terminal voltage. Under normal circumstances, the positive and negative terminals of the absolute value of the voltage should be between 300 and 380 v, in the process of measurement, the voltage will gradually reduce. If the positive and negative terminals of the photovoltaic controller of voltage imbalance, a terminal to 0 V or close to 0 V, and the other terminal more than 600 V, and voltage remains the same, in the process of measuring the photovoltaic controller exists ground fault can be determined. Determine the failure group string disconnect the output of the main circuit breaker fault photovoltaic controller, photovoltaic power generation in input measurement in each group list of positive and negative voltage at the input. Use 3. Described in article 1, and a method for determining the fault photovoltaic controller can be determined in a set or more sets of strings exist the possibility of cable grounding fault. Determine the cause of the failure in the anode grounding fault, for example, when measuring grounding failure group list of the positive and negative terminals of the voltage, the anode voltage of 0 V or close to 0 V, the absolute value of the cathode voltage of 700 V or more. Is the equivalent circuit diagram of ground fault can be measured point a of voltage of 0 V, point b of the absolute value of voltage is 700 V or more, it can quickly and efficiently determine the ground fault. Most of failures are caused by photovoltaic controller connected to the cable damage. And vice versa. By measuring the inverter DC grounding voltage at the ends of the power distribution ark each photovoltaic controller plus or minus, can quickly determine the cause of the pv group string of earth fault and fault point location, and then quickly handle failure, eliminate the fault point, recovery failure pv group list of running, to reduce ground photovoltaic power generation capacity and the influence of safety equipment.