As the solar photovoltaic industry continues to become an increasingly important share of the energy mix, the balance of system component technology is continuously evolving to help lower the cost of energy production. In the past few years, the industry has seen a tremendous jump from 600 V DC inputs to 1000 V DC inputs, which represent the majority of utility-scale solar PV installations. The next step in this trend, that is already undergoing, consists of systems with 1500 V DC inputs, which, by increasing the voltage level, enable higher power output capability by up to 50 percent, thus decreasing system losses and balance-of-plant costs.
Major challenges of this trend are:
- the issue of higher voltage requirements affecting the design of the system and insulation requirements;
- temperature, because PV plants often operate at high temperatures reaching 70° C;
- components for the 1500 V DC PV utility-scale installations may have to be designed for bidirectional current flow;
- components must ensure safe processing of 1500 V DC power, as well as reduced power losses, reduced number of poles, integrated heat dissipating and advanced arc extinguishing technologies;
- components must also handle more current, that could be up to 6000 A depending on the device.
This trend allows utility-scale PV combiner boxes and inverters to handle more power and some of the new products can handle two 1500 V DC inputs simultaneously.
ABB has developed 1500 V DC low-voltage components in order to process higher power. They include switches, molded-case circuit breakers, contactors, surge protection devices and voltage/current sensors. Some components are rated up to 3000 A / 1500 V DC and carry various certifications, UL and IEC included.