Patent ID: 6127793
Filing Date: 2000-10-03
Classification: G05B,H02P

Abstract:
A method for detecting optimal parameters for speed control of an electric motor, the method comprising:determining controller parameters in branches with different control characteristics, which comprises a controller of a control circuit for the electric motor;exciting the control circuit by different test signals, wherein each of the different test signals is chosen to excite only a defined branch of the controller;changing the controller parameters until the control circuit shows a normal control behavior and that the controller parameters for one or several branches of the controller determined in this way are set in the appropriate branch of the controller;supplying a first test signal to the electric motor for setting an amplification in a proportional branch of the controller;determining a chronological progression of an actual rpm (ni) of the electric motor in a measuring interval and is evaluated by a first evaluation function,starting with a slight amplification in the proportional branch and an integral branch of the controller, increasing the amplification in the proportional branch of the controller until the start of oscillation of the control circuit is detected by the evaluation by the evaluation function;multiplying the amplification of the proportional branch of the controller at the start of the oscillation by a factor of less than 1 and is set in the proportional branch of the controller;supplying a second test signal to the control circuit as a command variable for setting the amplification in the integral branch of the controller;determining the chronological progression of the actual rpm (ni) of the electric motor in a measuring interval, is evaluated by a second evaluation function, and a deviation from a set point rpm (ns) is quantized in the measuring interval by an error function; andstarting from a strong amplification, wherein an oscillation occurs, reducing the amplification in the integral branch of the controller until a minimum of the error function is provided, and this amplification is set.