Layout Schematic

FIGURE P1.4 Tethered platform using side thrusters for positioning<sup>6


6</sup> Muñoz-Mansilla, R., Aranda, J., Diaz, J. M., Chaos, D., and Reinoso, A. J.,
system is to be designed in which the objective is to minimize the drift, Y, and an angular deviation from the vertical axes, ϕ (not shown). The disturbances acting on the system’s outputs are the force, F, and the torque, M, caused by the external environment. In this
problem, the plant will have one input, the force delivered by the thrusters (F_u) and two outputs, Y and ϕ. Note also that this is a disturbance attenuation problem, so there is no command input. Draw a block diagram of the system indicating the disturbances F and M, the control signal F_u, and the outputs Y and ϕ. Your diagram should also have blocks for a controller, the one-input two-output plant, and a block indicating how the disturbances affect each of the outputs.

15. 
    In the Case Study of Section 1.4, an antenna azimuth angle is controlled, and its corresponding block diagram is shown in Figure 1.8(d) in the text. There, the sensor used to measure the antenna’s azimuth angle is a potentiometer.
    
    1. 
       Modifytheblockdiagramifthesensorusedtomeasure the antenna’s angle is an accelerometer.
       
    2. 
       Modifytheblockdiagramifthesensorusedtomeasure the antenna’s angle is a gyroscope.
       
16. 
    Figure P1.5 shows the topology of a photo-voltaic (PV) system that uses solar cells to supply electrical power to a residence with hybrid electric vehicle loads (Gurkavnak, 2009). The system consists of a PV array to collect the sun’s rays, a battery pack to store energy during the day, a dc/ac
    

inverter to supply ac power to the load, and a bidirectional dc/dc converter to control the terminal voltage of the solar array according to a maximum power point tracking (MPPT) algorithm. In case of sufficient solar power (solar insolation), the dc/dc converter charges the battery and the solar array supplies power to the load through the dc/ac inverter. With less or no solar energy (solar non-insolation), power is supplied from the battery to the load through the dc/dc converter and the dc/ac inverter. Thus, the dc/dc converter must be bidirectional to be able to charge and discharge the battery. With the MPPT controller providing the reference voltage, the converter operates as a step-up converter (boost) to discharge the battery if the battery is full or a step-down (buck) converter, which charges the battery if it is not full.⁷
In Figure P1.5, the Inverter is controlled by the Power Manager and Controller through the Current Controller. The Power Manager and Controller directs the Inverter to take power either from the battery, via the Bidirectional Converter, or the solar array, depending upon the time of day and the battery state

Applications of QFT Robust Control Techniques to Marine Systems. 9th

IEEE International Conference on Control and Automation. December 19–21, 2011, pp. 378–385. (Figure 3, p. 382).
⁷ For a description of all other operational scenarios, refer to the above-listed
reference.

HEV
Plug-in HEV

^{+ V}PV
V_PV


^IPV D
_V *

Inverter

BD
Converter Controller
Q₁ Q₃ ^{Lo I}u

^IPV
–
MPPT
PV
G V_c I_b

Q₄ Q₂

+ ^Io V_o
–
+ _IL ⁺
LOAD ^AC V_u
^– –

L_P
⁺ I_b
V_b
–

Q₅

+
C_c V_c
Q₆
SOC


Time
G I_O


^Current I_L
Controller

	I* u
Power Manager and Controller

Bidirectional Converter