Photovoltaic system is becoming more and more popular as a renewable energy, but it also brings more and more power quality problems. This artical will introduce a case of photovoltaic power quality in a machinery factory. Analyze the reasons why he faced a penalty of $20000 after installing the photovoltaic system and put forward solutions.
The background of the power distribution system of the machinery manufacturer is introduced as follows: he installed a 2500kVA transformer with a load power of about 1200~1500kw, and he installed a 1200kvar capacitor compensation cabinet with a target power factor of 0.95. Before installing the photovoltaic system, his monthly average power factor was basically greater than 0.95, and the system operated normally.
Phenomenon And Reason
After the machinery manufacturer installed the 2100kw photovoltaic system, the monthly average power factor fell to 0.53 and suffered a penalty of US $20000. Let’s analyze the reasons for being fined:
The old reactive power compensation controller samples only phase a current and phase BC voltage, and its default is that the load consumes positive active power. When the photovoltaic power is greater than the load power, the active power consumed by the system is negative, and the reactive power compensation controller cannot work normally, resulting in the normal compensation of 1200kvar reactive power compensation cabinet.
The photovoltaic system generates a lot of power, and the active power consumed from the grid is only 30% of the previous one. Moreover, because the reactive power compensation system cannot work normally, the reactive power consumed from the power grid has also increased, resulting in a sharp drop in the power factor to 0.53.
How to solve the power quality problem caused by this photovoltaic system?
- Increase SVG to ensure that the capacity and compensation accuracy of reactive power compensation cabinet can meet the reactive power compensation requirements of the whole system.
- SVG is used to control the original capacitance compensation cabinet to form a hybrid compensation scheme, and the target power factor is set to 1, so that the whole reactive power compensation system can compensate reactive power as much as possible.
- If the access point of the photovoltaic system can be selected, try to install it in front of the reactive power compensation cabinet, such as this point, to maximize the use of the original reactive power compensation system.
The machinery manufacturer added two 100kvar SVGs of enjoypowers and formed a hybrid compensation system with the original capacitor. The customer’s monthly average power factor was restored to more than 0.95.
Enjoypowers has a lot of experience and application cases in solving the power quality problems of photovoltaic systems. If you encounter power quality problems in the feasibility planning of photovoltaic systems, please contact me.