A variable-frequency drive (VFD) (also termed adjustable-frequency drive, variable-speed drive, AC drive, micro drive or inverter drive) is a type of adjustable-speed drive used in electro-mechanical drive systems to control AC motor speed and torque by varying motor input frequency and voltage.ariable-frequency drives are also categorized by the following load torque and power characteristics: 1  Variable torque, such as in centrifugal fan, pump, and blower applications. 2  Constant torque, such as in conveyor and positive-displacement pump applications.
For example, the UK is a unitary state (for the most part) whereas the US is a federation. A parliamentary form of government simply means that the executive branch/ministers/cabinet are part of the legislative body. Both unitary and federal states can have parliaments. For example, India is a federation with a parliamentary system where as the UK is a unitary state with a parliamentary system. m200220232
bicameral system. bicameral system (bÄªkÄmËÉrÉl) [ key ], governmental system dividing the legislative function between two chambers, an upper, such as the U.S. Senate and the British House of Lords, and a lower, such as the U.S. House of Representatives and the British House of Commons.ore on bicameral system from Infoplease: 1  legislature: Types of Legislatures-Types of Legislatures Two common types of legislature are those in which the executive and the 2  ... Encyclopedia: Political Science: Terms and Concepts-Encyclopeadia articles concerning Political Science: Terms and Concepts.