Customer: EUROCOOP INSPEKTA Inc.
Site: Dubňany – Jarohněvice (South-Moravian region)
Description of the technology:
Total number of panels: 15,368 (240Wp/panel)
Total installed capacity in the DC PV panels: 3.6883MWp
Total installed capacity on the AC side: 3.5MW
Maximum power which can be supplied to the DN: 3.15MW
Facilities used:
Panels: JC240S-24/Bb, 1640mmx990mm size
String boxes: ZPA Industry Inc.
Inverters: Siemens SINVERT 1000MS TL
Satcon Power Gate Plus 500kW
Design:
The whole PVPP is divided into 5 sections: A - 1.0137 MWp, B - 1.0137 MWp, C – 0.5376MWp, D - 0.5856MWp, E - 0.5376MWp. The PV panels are connected in series and form a string. One string consists of 20 (22) panels. Power from the whole string is fed to an SB connection cabinet. Here the strings are connected to form 2 parallel groups which form a larger unit, bay, marked with respect to the connected SB distribution board 1000mm x 800mm x 300mm. The SB distribution board contains GE EP104UC circuit breakers for the strings, UPFI 10-8 inverters for measuring currents from the strings, PLC GE VersaMax Mikro 40 point, 110/24VDC/3,5A Phoenix power supply, UPTF temperature converters (one Pt100 thermometer is located inside the cabinet, one is located on a panel), converter for optical communication, and Cu buses for output. There are 2 Cu buses, each for a group of 8 string groups. Either bus has its own output cable. The outputs from the SB cabinets are brought in 2 groups (A and B) are brought to an RSS_C combining switchgear 2000mm x 600mm x 600m size. The output from this cabinet is brought to the inverter.
Each PVPP section is an autonomous unit with central inverters and unit transformers. The transformers and inverters are accommodated in technological containers (Siemens inverters). Satcon inverters (outdoor design) are located near the containers. The outputs from the sections are brought to the R1 substation, located on the PVPP premises. This substation comprises 2 technological containers. The substation accommodates HV switchgears, internal consumption transformers, as well as LV and I&C switchgears (in a separate room).
Monitoring system
This system serves to monitor the whole PVPP, including the HV substation, Furthermore, this system controls the inverter output from each section so that the limiting level of 3.15MW for power supplied to the grid is not exceeded. The control system also provides P/Q regulation in accordance with requirements from the Eon load-dispatching centre.
The proposed monitoring system technology is based on a concept where a large part of the logic and complete visualisation are provided by the Cimplicity SCADA system (GE IP). This is real time software running under Microsoft Windows XP, where this software has a higher priority than the other applications. The control system PC is the hardware part of the system.
The monitoring system in the R1 substation includes a computer (control system PC), PLC GE IP 90-30 (PLC), network components, and two GSM/GPRS modems. The computer without the rotary components labelled UNO3072L is built on a motherboard with an Intel 945GM+ICH7M chipset. Processor: Intel Celeron 1,3GHz, operational memory 1GB DDR2, Windows XP operating system. Monitoring is provided through safe remote access and locally through a 17” LCD. The PC collects data from connected loops in the substation, from fire detectors and from room temperature measuring instrumentation. To the PLC is connected a group of genius blocks to monitor and control the HV switchgears. By communication, the PC also collects instantaneous data of electric currents flowing in the SB switchgears and is able, based on comparison and measurement, to identify individual failed strings and panel groups. The SB switchgears are also monitored by the control system constantly, and appropriate alarms are generated if any failure is detected (e.g. disconnected circuit breakers, communication failure).
Remote access can be implemented in two ways: either through
a GSM/GPRS modem or through WiFi. The modem is primarily used for sending SMS if a failure occurs and/or alarm is generated.
The other modem is a standby facility in case of problems with the PC.
It is capable of providing for restart of the PC.
The control system PC is connected to the Internet through a public static IP address at a sufficient speed. This makes it possible, through
a remote desktop or the web interface to connect to the control system PC and monitor (and/or directly control) the current status of the technology.
Communication
The entire system is interconnected through a communication network which interconnects the sections with the control system. Communication interconnection of the sections within the control system between:
- the control system and the PLC in the HV substations and the PLC in the interconnecting SB cabinets within a PV array is implemented by means of the Modbus RTU protocol for the RS232/RS485 bus, which is converted to optics by optics/metallics communication converters which are interconnected by a communication bus in the circular topology;
- the control system, inverters and measuring modules is implemented by means of the Modbus TCP/IP protocol on the Ethernet bus, which is converted from metallics to optics by means of an Ethernet media converter;
- the control system, protections, and current supplies is implemented by means of the Modbus RTU protocol on an RS485 metallic bus;
- the control system and the GENIUS units is implemented by means of the GENIUS protocol on
a GENIUS metallic bus;
- the control system and the GSM Modems is implemented through communication on an RS232 metallic bus.
Scope of work and supplies:
· Cost about CZK 44.5m
· Project Power evacuation from the photovoltaic panels to the R1 substation; a HV substation and power evacuation to the 22kV grid; monitoring system; communication network; internal consumption
· Manufacture of switchgears 46 string boxes, 5x RSS combining cabinets, 6x RNN internal consumption, AT standby supply switchgear, RA monitoring system switchgear, SM2 measurement switchgear, AXY interface switchgear
· Cables: 102,500m of cabling for the photovoltaic systems;
10,100m NYY for DC power transmission;
1,800m HV (22kV) cables for power evacuation;
4,150m optical cables (communication);
5,000m metallic cables (sensors, internal consumption)
· Electrical installation: Complete installation and commissioning of the above electrical equipment accommodated in 5 containers on the PVPP premises
· Commissioning and start-up: Complete PVPP (including tests of the panels)
Contract signature 27 October 2010
Commissioning/start-up: 19 December 2010
ZPA Industry Inc. is an Invensys Wonderware Registered System Integrator