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- Homework Statement:
- Determine the required value of feedback (H) to stabilize this heater output

- Relevant Equations:
- θo= θD*P*He / -θD+T*H

Just need a bit of guidance to make sure that I am heading the right way.

Question is:

Fig 3 shows the block diagram of the control of an electric heating

system. The heater is driven from a voltage-controlled power supply, the

voltage V1 being derived from a potientiometer. The output temperature,

θO, is subject to disturbances, θD, because of changes in the ambient

temperature. It is proposed to apply 'disturbance feedback control' to the

system by the inclusion of a transducer that measures the external

temperature and feeds a signal back to the input via a proportional

controller of gain H.

Determine the required value of H to eliminate the effect of the disturbance.

I have attached the block diagram to this post

So far I have

θo= θD*P*He / -θD+T*H

θD = Distubance

P = Power Supply = 2

He= Heater = 0.4

T = Transducer = 0.05

H = Proportional control = ???

But does θD then cancel out as there is a positive and negative on both sides?

This would then give:

θo= P*He / T*H

Is this the correct way to be going as the next step for this equation would be to make H the subject to equal a value?

Thanks In Advance

Question is:

Fig 3 shows the block diagram of the control of an electric heating

system. The heater is driven from a voltage-controlled power supply, the

voltage V1 being derived from a potientiometer. The output temperature,

θO, is subject to disturbances, θD, because of changes in the ambient

temperature. It is proposed to apply 'disturbance feedback control' to the

system by the inclusion of a transducer that measures the external

temperature and feeds a signal back to the input via a proportional

controller of gain H.

Determine the required value of H to eliminate the effect of the disturbance.

I have attached the block diagram to this post

So far I have

θo= θD*P*He / -θD+T*H

θD = Distubance

P = Power Supply = 2

He= Heater = 0.4

T = Transducer = 0.05

H = Proportional control = ???

But does θD then cancel out as there is a positive and negative on both sides?

This would then give:

θo= P*He / T*H

Is this the correct way to be going as the next step for this equation would be to make H the subject to equal a value?

Thanks In Advance

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