University of South Wales Master of Sciences Thesis
Series-Parallel Hybrid Power System
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- Điều hướng trang này:
- Series hybrid power systems
- Fig. 2.40 shows a typical series configuration of HPSs.
| 2.7.7. Series-Parallel Hybrid Power System
Based on how the load is supplied from the RESs and the Genset, a hybrid power system whose power is to be supplied from wind turbine, PV-system, a diesel generator and a battery bank, two broad classes of configurations are explained in [5, 28]. These are • Series hybrid systems • Parallel hybrid systems Series hybrid power systems In the series HPSs scheme, all the DC power is fed into the battery. Thus, the power generated by diesel generator, wind generator and solar PV-array are used to charge a battery bank before supplied Standalone hybrid generation system for the remote area of Thar, Pakistan to the load. Therefore, each component has to be equipped with an individual charge controller and in the case of diesel generator with a rectifier. Then, the inverter will convert the DC power stored in the battery bank to AC at standard level of voltage and frequency and then supplies to the AC load. The charge regulators used can prevent overcharging of the battery bank from the wind/PV generators when the renewable power exceeds the load demand and the batteries are fully charged. In a similar fashion, they will protect the battery bank from deep discharge when demand exceeds the supply, if it happens. Fig. 2.40 shows a typical series configuration of HPSs. This type of configuration is also termed as Centralized DC-bus topology in the sense that all the energy generators and the battery are connected at the DC-bus and the AC load is supplied via a single point. Here, it has to be noted that the AC powers from the wind turbine and the diesel generator must be converted into DC by utilizing AC/DC converters or rectifiers before power is delivered to the DC bus where the BB is connected. This configuration type results in relatively simple implementation. There are drawbacks, however, with this configuration. - As most of the energy passes through the battery, it results in increased cycling of the battery bank and reduces system efficiency [27, 28]. - There is a need for large size of battery bank to limit the depth of discharge and there is limited control of the diesel generator as the system is based on level of charge in the battery rather than the site load [28, 29]. - Most of the existing systems operate at battery voltages between 24 V and 120 V. In this scheme, the use of standardized components becomes impossible and every solution has to be engineered individually increasing the cost of the system [28, 29]. tải về 6.62 Mb. Chia sẻ với bạn bè của bạn:
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