Lead-lag compensation of a control system PDF

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Compensation techniques of a control system. Lead network and lag network....

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Topic:Lead, Lag, Lag-lead compensator Effect on addition of Poles and zeros on Root locus Effect of Addition of Poles on Root Locus

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Effect on addition of Poles and zeros on Root locus Effect of Addition of Poles on Root Locus

Effect of Addition of Poles on Root Locus • The addition of a pole to the open-loop transfer function has the effect of pulling the root locus to the right, tending to lower the system’s relative stability and to slow down the settling of the response. 2/27/2021

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Effect on addition of Poles and zeros on Root locus Effect of Addition of zeros on Root Locus

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Effect on addition of Poles and zeros on Root locus Effect of Addition of zeros on Root Locus

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Effect on addition of Poles and zeros on Root locus Effect of Addition of zeros on Root Locus

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The addition of a zero to the open-loop transfer function has the effect of pulling the root locus to the left, tending to make the system more stable and to speed up the settling of the response.

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Physically, the addition of a zero in the feed forward transfer function means the addition of derivative control to the system.

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The effect of such control is to introduce a degree of anticipation into the system and speed up the transient response.

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator – lead compensators • If a sinusoidal input is applied to the input of a network, and the steady-state output (which is also sinusoidal) has a phase lead, then the network is called a lead network. – lag compensators • If the steady-state output has a phase lag, then the network is called a lag network. – lag–lead compensators • In a lag–lead network, both phase lag and phase lead occur in the output but in different frequency regions. • Phase lag occurs in the low-frequency region and phase lead occurs in the high-frequency region.

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator

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Lead, Lag, Lag-lead compensator

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