‘ Energi ‘ Metal-enclosed medium voltage capacitor systems and harmonic filters are designed for indoor and outdoor applications in commercial, industrial, and utility power systems requiring power factor correction, motor start support, harmonic filtering, as per IEC compliance, can increase systems capacity. A “ capacitor bank “ generally consists of several single-phase or three-phase capacitor units assembled and interconnected to produce very powerful system.
Various configurations are possible based on the application as listed below:
- Fixed Bank
Qc/Sn < 15% the reactive power of the capacitor banks is constant and they are started up or shut down when a predetermined KVAr value is reached. It is an “ on/off ” type of operation.
- Automatic Bank
Qc/Sn > 15% the customer specifies automatic startup or shutdown for the capacitor bank (controlled by relay). The reactive power of the capacitor bank is split into “ steps ” with the possibility of starting or stopping more or fewer steps. The reactive power corresponds to the change in load requirements.
- Harmonic Filtering Bank
Harmonics are an important aspect when considering power factor correction. The range includes a number of options to overcome these harmonics.
Modern electrical equipment consists of nonlinear devices which generate harmonics. Examples of these devices include the following:
- Equipment containing electronics that control other apparatus. Eg. variable speed drives, soft starters, static compensators, rectifiers, etc.
- Arc furnaces
- In certain cases, transformers, reactors and rotating machines
- Domestic appliances
Harmonics are not only found in industrial networks, they can also spread into the distribution network and cause problems for other power users. Common problems that harmonics can produce include:
- Overloading of capacitors, leading to malfunctioning and premature aging
- Increased losses, eg. machines will operate at increased temperatures
- Resonance problems between the inductive and capacitive parts of the network
- Malfunctioning of control systems
- Interference with telecommunication and computer equipment
- Disturbances in ripple control systems
- High currents in neutral conductors
Different Configurations for Metal Enclosed Capacitor Banks