18 December 2017 Abstract- Thisstudy contribute to investigate a dynamic system of a DC motor using a tachometeras a speed sensor. The tachometer used in this study is integral to the DCmotor. A root locus is used to design feedback compensators to improvetransient response. Mostly the systems choose based on characteristics otherthan transient response. Instead of we change the original system; the systemcan be compensated with additional poles and zeros. Hence, a compensated systemprobably has a root locus that can goes through the required pole location withincertain value of gain.
Addition of compensating poles and zeros does not involvedwith the power output requirement of system but it is generated with a passive networkor an active network. Compensators can also been used to improve thesteady-state error. When a dynamic compensators are been used, it will allow usto meet transient and steady-state error specification at the same time. Thus, wecan improve the transient response by adding a differentiation while adding anintegration toimprove thesteady-stateerror. I.
INTRODUCTIONControl systems are an integral part of the overallsystem thus they must be considered from the very beginning of the designprocess. We must be able to influence the response of the system to make surewe can control the dynamic system. Both transient response and stability informationcan be displayed by root locus. In order to get the whole idea of the changesin transient response, we can sketch the locus. We can choose a desired loopgain to achieve a proper transient response specification.
A desired transientresponse is flexible and can be improved when we designed transient responsesthat are out of the root locus. One of the disadvantages of compensating systemwith additional zeros and poles are that the system order becomes larger. Increasingthe gain will reduce the steady-state error, but at the same time the percentof overshoot become larger. Meanwhile, when we reduce the gain to reduce thepercent overshoot we increased the steady-state error. Ideal compensators are compensatorsthat use original integration to improving steady-state error and originaldifferentiation to improve the transient response.
Electrochemical ideal compensatorsthat often been used to improve transient response is tachometers. For passiveelements, these compensators are implemented with resistors and capacitors arenot ideal compensators. Vary advantages of passive networks are including lessexpensive and it do not require any additional power sources for theiroperation. II. CONFIGURATIONSTwo configurations of compensatorsare cascade compensation and feedback compensation.
The techniques are modeledin Figure 1. For feedback compensation, H(s) is placed at the feedback path.Both compensation change the open-loop zeros and poles, then it creates a newroot locus that goes through the required closed-loop pole location.