About Multilevel Inverters
There are many industrial uses of inverters. Many industrial applications require high power for operation of equipment. However, some equipment in industrial applications requires power in the range of low to medium power. The need of power for suchequipment changes according to requirement. The use of high power load is beneficial for the operations of some motors but detrimental to the operation of others. For instance, some medium voltage motor drivers and utility applications need medium power for their operation which will get severely damaged if they are connected to high power sources. Even the best luminous inverter has options to find a solution to this problem. The solution entails the use of multilevel inverters, which switch between medium power and high-power situations. It works like a normal inverter but provides an alternative to medium and high voltage situations.
Types of multilevel inverters-
- Diode clamped multilevel inverter-
- There are capacitor banks which are placed in series which are used to provide the multiple voltage levels along with diodes.
- The diodes are the show stoppers of this device because they transfer a limited amount of voltage, which essentially reduces the stress on other electrical devices.
- However, the main drawback of this type of multilevel inverter is that the maximum output voltage produced is only half the input DC voltage. The solution to this problem consists of increasing the number of switches, diodes, and capacitors. These are limited to the 3 existing levels because of capacitor balancing issues.
- While buying luminous inverter online, a consumer can see the different varieties presented to them. They also sell multilevel inverters, which has a big advantage of back to back power systems.
- It is used for applications such as static variable compensation, variable speed motor drivers, high voltage system interconnections, and high voltage DC and AC transmission lines.
- Flying Capacitor Multilevel Inverters-
- A series of capacitor clamped switching cells constitute the circuit of these multilevel inverters.
- The limited amount of voltage is transferred by the capacitors to electrical devices. The switching states are like the diode clamped inverters, but clamping diodes are not required.
- Active and reactive power flow can be controlled with this type of multilevel inverter.
- The initial drawback persists. The output is half of the input DC voltage, but there is a switching redundancy within phase to balance the flying capacitors. Switching losses occur due to high frequency switching.
- It is used in induction motor control using direct to rquecontrol (DTC) circuit, Static variable generation, both AC-DC and DC-AC conversion applications, converters and harmonic distortion capabilities, and sinusoidal current rectifiers.
- Cascaded H-Bridge Multilevel Inverter-
- It is a combination of capacitors and switches and each level requires less number of components. Easily scalable power supplies are provided to a topology that consists of a series of power conversion cells.
- This combination has been named H-bridge and a separate DC voltage is applied to each H-bridge. The H-bridge cells can provide 0 voltage, positive, and negative voltage.
- It is used in electric vehicles, active filters, power factor compensators, and back to back frequency link systems.