DE1588810C - Building block for an electronic controller - Google Patents

Description

form

a = e -sin ωί

sin ωί

", where μ is a proportionality factor and e is the signal amplitude.

3. Controller module according to claim 1, characterized by the series connection of the integrating Transmission element (2) with a computing circuit (3), which converts the output signal of the filter into the third power raises, the further, differentiating transfer element (8) and finally the Computing amplifier (1), which is the cube root from the output signal of the differentiating transmission element (8) pulls (Fig. 3) so that the output of the circuit is in phase with the input signal (α) and with an input signal the form

α = e -sin ωί
the output signal die-form

λ-e

γ =

where λ is a proportionality factor and e is the signal amplitude.

4. Controller module according to claim 1, characterized in that the one computing amplifier (1) raises the input signal in die_Potenz l / p , that a transmission element (2) is provided and that the other computing amplifier (3) the output .signal of the transmission element in the power η Φ ρ raises.

The invention relates to a module for an electronic controller with non-linear transmission characteristics.

As is well known, linear controllers are subject to some restrictions caused by the relationships between Gain and phase are conditional according to Bode's law: In particular, the gain can only be changed depending on the frequency if the phase is changed at the same time will.

According to one-older suggestion, one is electronic Controller with non-linear transfer characteristics, in which the control deviation is fed to the parallel connection of two transmission elements, designed so that the one transmission element from the series connection of a first linear transmission element and an absolute value generator and the gain is assigned that the second transmission element also has linear transmission behavior and is assigned to the phase of the control deviation and that the output variables | j> | and ζ the transfer elements on a multiplier circuit

switched ', whose output variable | j> | · Ζ one Square root with the output signal

± y \ y \ · \ ζ \ · sign z

is supplied as a manipulated variable.

With this controller, the phase rotation is avoided, but there is the disadvantage that Certain non-linearities of the output signal occur, which are caused by a series of harmonics to express.

The object of the invention is; to create a controller module of the type mentioned above, with which Help the gain of a signal as a function of the frequency can be changed without

the phase position is changed, whereby the many harmonics are avoided.

According to the invention, this object is achieved by a controller module which has a linear frequency-dependent has transmission element that is reciprocal between two exponentiating computing circuits with each other Exponents of the same order are connected in series, one of which with the control deviation signal is applied and the other delivers the desired output variable.

The module according to the invention can be used to build regulators whose output signal is in phase with the input signal, while the ampli-. tude of the output signal is a function of the signal frequency.

One embodiment of the invention is characterized by the series connection of the one potentiating Arithmetic circuit that supplies a signal whose amount is equal to the square root of the amount of the input signal and whose sign is equal to the sign ' of the input signal is; with the integrating transmission link, the further exponentiating arithmetic circuit, which supplies a signal, the amount of which is equal to the Square of the amount of the output signal of the transmission element and "its sign is equal to the Is the sign of this output signal, and finally with the differentiating transmission element, so that, ■ the output signal of the circuit is in phase with the input signal and, for an input signal, the shape

a = e · sin ωί the form

7 =

where μ is a proportionality factor and e is the signal amplitude.

Another development of the invention is characterized by the series connection of the integrating Transmission element with a computing circuit that converts the output signal of the filter to the third power raises, the further, differentiating transmission link and finally the processing amplifier, the "the The cube root is drawn from the output signal of the differentiating transmission element, so that the output signal of the circuit is in phase with the input signal and, for an input signal, the shape

sincjf

α = e

the output signal the shape

le .
γ = - g / T ' ^{sm lot}

15th

20th

owns ", where λ is a proportionality factor and e is the * signal amplitude.

According to a further embodiment of the invention it is provided that one computing amplifier raises the input signal to the power l / p, that a transmission element is provided and the other computing amplifier raises the output signal of the transmission element to the power η 7t p.

Further details and advantages of the invention emerge from the following description of an in Embodiment of the invention shown as an example in the drawing. ' In the drawing represents

F i g. 1 the block diagram of a controller module according to the invention,

Fig. 2 in the block diagram with a transmission element connected controller module according to Fig. 1,

F i g. 3 shows the block diagram of a modification of the invention.

In Fig. 1 you can see a controller module according to the invention for a controller with non-linear transmission characteristics, which has a computing circuit 1 that pulls the cube root from the input signal α, an integrating and delaying linear frequency-dependent transmission element 2 and finally a computing circuit 3, which the output signal of the Transfer member 2 raises to the third power and provides a converted output signal β. ■

The potentiating computing circuits 1, 3 consist in a known manner of amplifiers 4, fixed resistors 5 and non-linear resistors 6. The transmission element 2 has a capacitance in a known manner 7, which is connected in parallel to the amplifier.

The input signal is given

α = + e · sin ωί. . '

If you limit yourself to the first harmonic, computing circuit 1 converts this signal into Signal um whose phase is unchanged (but whose sign is due to the electronic switching of the Amplifier is reversed):

- λ

sin ωί.

The integrating transmission element 2 receives this signal and delivers it to the input of the computing circuit 3 the following signal:

This signal has a delay of.-Τ / 2 compared to the input signal a.

The computing circuit 3 raises this signal to the third power and thus provides an output signal whose first harmonic

üli

COStUf

It can be seen that the controller module according to the invention in FIG. 1 supplies a signal whose phase shift is the same as that of the transmission element 2 or F , whose amplitude is practically linear (ie from degree 1 in e) and whose gain depends on the frequency ω in a different way than the gain of the transmission element F.

In the example chosen and shown, the frequency function of the amplitude or gain introduced by the integrating transmission element 2 is: 1 / ω. The 'frequency function of the entire controller module is therefore 1 / ω ³ .

If a differentiating linear frequency-dependent transmission element is connected to the controller module in FIG. 1, then the signal derived from β becomes

γ - H τ- · sm ωί.

A signal is thus obtained which is in phase with the input signal and linearly of the amplitude e depends, but is inversely proportional to the square of the frequency ω.

So if the natural frequency of the transmitted control signal increases in a given control loop, then, according to the invention, the output amplitude of the controller is reduced in relation to the second Power of this signal frequency change. If instead of the exponent 3 one had an exponent ρ for the Calculation circuits 1 and 3 selected, then the frequency-dependent gain factor would be in the case of the Fi g. 2 have the following size:

In Fig. 3 shows a modification of the invention in which the controller module 9 in FIG is replaced by a controller module 11 and the boxes in the block diagram of computing circuits or transfer elements according to FIG. 1 and 2 represent. The signal

a = e · sin ω t
is processed as follows: ■ ■

55

6o

Integration in R: - \ · cos ωί

Elevation to the 3rd power in Q: ■ · cos ωί

μ e ³
Derivation in A:

sin ωί

Extract the 3rd root in P: +

sin ωί.

COS ωί.

It can be seen that the signal γ obtained is a function of e and that the gain changes with 1 / ω ² ' ³ .

i bööÖlü

The controller modules can be connected in series or in parallel "in order to obtain special results.

If the power ρ is arbitrary, then the computing circuits P or 1 and Q or 3 have the following task: In P one forms according to the schematic representation in F i g. 1 z. B.

δ = -] / \ a \ · sign α
and in an analogous way in Q

β = \ e \ "■ sign ε. -

Was the. If the statement "a computing circle raises to an arbitrary power p" is made, then one understands by this that this computing circle carries out the following operation between its input E and its output S:

S = IJSl'- sign E.

In practice, these functions are realized by suitable electronic circuits, e.g. B. by computing circuits that have a non-linear resistance of suitable characteristics in their input or feedback circuit. If one disregards the function dependency of the controller component according to the invention, then one can of course form a circuit in which P and Q correspond to the operations "pulling the pth root" or "raising to the nth power (η Φ ρ) «, Whereby the preceding sign conditions must be taken into account.

Of course, one can consider the special case ρ = 2 and 7Ϊ = 2, which has proven to be advantageous in practice.

Furthermore, all changes of details corresponding to the inventive concept can be used in the example can be made without departing from the scope of the invention.

1 sheet of drawings.

Claims (2)

■ Patent claims: 1. Component for an electronic controller with non-linear transmission characteristics, identified by a linear frequency-dependent transfer element (2 or 8), which is connected between two potentiating computing circuits (1, 3) is connected in series with reciprocal exponents of the same order, of which the one has the control deviation signal applied to it and the other the desired output variable supplies. 2. Controller module according to claim 1, characterized by the series connection of a potentiating computing circuit (1) which delivers a signal (δ) whose amount is equal to the square root of the amount of the input signal (α) and whose sign is equal to the sign of the input signal, with the integrating transfer element (2), the further exponentiating computing circuit (3), which supplies a signal (ß) , the amount of which is equal to the square of the amount of the output signal (ε) of the transfer element (2) and whose sign is equal to the sign of this output signal, and finally with the differentiating transmission element (8) (FIG. 2), so that the output signal (γ) of the circuit is in phase with the input signal (α) and with an input signal of the form