5. Characteristics of the studied PV system

#### 5.1 Backup PV systems

To overcome the problem of power cuts, 20 backup systems have been installed in 20 cities in Cameroon at the end of 2006. These systems are essentially made up of monocrystalline solar modules (Hélios, 80Wc), batteries (Midac, 400 Ah) to backup during power cuts, and charge controllers (Steca, 20A) which regulates the energy flux and protects the batteries from overloading and deep discharge. There are generally three types of controllers [31, 32]: shunt controllers, series controllers, and maximum power point tracking (MPPT) system. The inverter called "inverter-chargers" can be connected to the

maintenance is scheduled at regular time intervals, independent of component wear, or if it still executes its function satisfactorily [26]. Preventive maintenance scheduling could be done using several strategies; the most common are usually with a minimal cost target that are based on the budget allocation for maintenance in accordance with the system priorities [27, 28]. The objective of this type of maintenance is to ensure the reliability of the system and to maintain the system in

It consists of the setup of a breakdown system. It is usually done in two stages: palliative corrective maintenance (fixing) which involves the start off of a system which is partially or totally broken up while waiting for a permanent repair of this system. In this case, the speed with which interventions are done is considered, and the action must take place as fast as possible for quicker start off of this system [20]. The goal of this action is not to repair the breakdown but to permit the system to fulfill part or the totality of it function [20]. Curative corrective maintenance (repairing) is a final setup of all the worn out elements of the system. Contrary to the fixing action, the repairing action is a planned one. In this case, the quality of the intervention is more important than speed. In the case of corrective maintenance on photovoltaic systems, diagnosis diagrams are first done in order to ease and help workers to determine the worn out elements knowing the causes of the breakdown. The essence of the approach "run-to-failure" or corrective maintenance is to replace the component with a new one when it is not able to perform its function [26].

There are several techniques for the detection of faults in PV systems; these techniques are summarized in Figure 2. These techniques have helped in improving the system reliability and lifetime of PV systems. The classification of different fault

its state of initial efficiency [29].

4.3 PV systems fault detection techniques

Fault detection techniques in DC and AC side of PV system [27, 29].

Figure 2.

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4.2 Corrective maintenance

Maintenance Management

Figure 4. (a) Shading and (b) vegetation and building.

Figure 5. (a) Soiling and dust accumulation and (b) vegetation.

5.2 Photovoltaic water pumping system

(a) Circuit breaker fault and (b) inverter fault.

Figure 7.

Figure 8.

Figure 9.

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(a) Wiring system fault and (b) poor tightening of connections fault.

On-Field Operation and Maintenance of Photovoltaic Systems in Cameroon

DOI: http://dx.doi.org/10.5772/intechopen.83730

Two water pumping systems are installed to provide water to the population of

an isolated site located at 10°23 N and 14°26 E. Each system has 13 kWp of PV generator associated to an automatic inverter. The pumping takes place over the

(a) Deep discharge of batteries and (b) sulfation of batteries due to lack of maintenance.

Figure 6. (a) PV junction box and (b) delamination and discoloration.

electricity network in the purpose of supplying the energy of the network, two types of inverters are used C1600-12 and C2600-24 (Studer compact) (Figures 4–9).

On-Field Operation and Maintenance of Photovoltaic Systems in Cameroon DOI: http://dx.doi.org/10.5772/intechopen.83730

Figure 7. (a) Wiring system fault and (b) poor tightening of connections fault.

Figure 8. (a) Circuit breaker fault and (b) inverter fault.

Figure 9. (a) Deep discharge of batteries and (b) sulfation of batteries due to lack of maintenance.
