A forced commutated thyristorized step-down chopper is shown. Neglect the ON-state drop across power devices. Assume that the capacitor is initially charged to 50 V with the polarity shown in the figure. The load current \(I_l\) can be assumed to be constant at 10 A. Initially, \(Th_M\) is ON and \(ThA\) is OFFThe turn-off time available to \( T_{H4} \) in microseconds, when \( T_{H4} \) is triggered, is ________ (rounded off to the nearest integer).
A forced commutated thyristorized step-down chopper is shown. Neglect the ON-state drop across power devices. Assume that the capacitor is initially charged to 50 V with the polarity shown in the figure. The load current \(I_l\) can be assumed to be constant at 10 A. Initially, \(Th_M\) is ON and \(ThA\) is OFFThe turn-off time available to \( T_{H4} \) in microseconds, when \( T_{H4} \) is triggered, is ________ (rounded off to the nearest integer).
Show Hint
Correct Answer: 50
Solution and Explanation
Given: \[ C = 10 \, \mu F, \quad V_S = 50 \, \text{V}, \quad I_L = 10 \, \text{A} \] Step 1: Time constant for capacitor discharge: \[ t_c = \frac{CV_S}{I_L} \] \[ t_c = \frac{10 \times 10^{-6} \times 50}{10} = 50 \, \mu s \] Final Answer: The turn-off time is \( 50 \, \mu s \).
Top Questions on Power
Consider a distribution feeder, with \( R/X \) ratio of 5. At the receiving end, a 350 kVA load is connected. The maximum voltage drop will occur from the sending end to the receiving end, when the power factor of the load is: \[ {(round off to three decimal places).} \]
Let \( C \) be a clockwise oriented closed curve in the complex plane defined by \( |z| = 1 \). Further, let \( f(z) = jz \) be a complex function, where \( j = \sqrt{-1} \). Then, \[ \oint_C f(z)\, dz = \underline{{2cm}} \quad {(round off to the nearest integer)}. \]
In an experiment to measure the active power drawn by a single-phase RL Load connected to an AC source through a \(2\,\Omega\) resistor, three voltmeters are connected as shown in the figure below. The voltmeter readings are as follows: \( V_{{Source}} = 200\,{V}, \quad V_R = 9\,{V}, \quad V_{{Load}} = 199\,{V}. \) Assuming perfect resistors and ideal voltmeters, the Load-active power measured in this experiment, in W, is ___________ (round off to one decimal place).
The steady-state capacitor current of a conventional DC–DC buck converter operating in continuous conduction mode (CCM) is shown over one switching cycle. If the input voltage is \(30\,\text{V}\), the value of the inductor used (in mH) is ____________ (rounded off to one decimal place).
Consider the state-space model
\[ \dot{\mathbf{x}}(t) = A \mathbf{x}(t) + B r(t), \quad y(t) = C \mathbf{x}(t) \]
where \( \mathbf{x}(t) \), \( r(t) \), and \( y(t) \) are the state, input, and output, respectively. The matrices \( A \), \( B \), and \( C \) are given below:
\[ A = \begin{bmatrix} 0 & 1 \\ -2 & -3 \end{bmatrix}, \quad B = \begin{bmatrix} 0 \\ 1 \end{bmatrix}, \quad C = \begin{bmatrix} 1 & 0 \end{bmatrix} \]
The sum of the magnitudes of the poles is ____________ (round off to the nearest integer).
Questions Asked in GATE EE exam
Given an open-loop transfer function \(GH = \frac{100}{s}(s+100)\) for a unity feedback system with a unit step input \(r(t)=u(t)\), determine the rise time \(t_r\).
- GATE EE - 2026
- Control Systems
- In the series circuit shown containing a voltage source (V), a diode (D), a resistor (R), an inductor (L), and a capacitor (C), which of the following components are considered linear?
- GATE EE - 2026
- Control Systems
Consider a linear time-invariant system represented by the state-space equation: \[ \dot{x} = \begin{bmatrix} a & b -a & 0 \end{bmatrix} x + \begin{bmatrix} 1 0 \end{bmatrix} u \] The closed-loop poles of the system are located at \(-2 \pm j3\). The value of the parameter \(b\) is:
- GATE EE - 2026
- Control Systems
- If P and Q are positive integers such that \(P^2 = Q^2 + 13\), find the value of the product \(PQ\).
- GATE EE - 2026
- Algebra
- For the circuit shown below, find the value of the load resistance \(R_L\) that will absorb the maximum amount of power from the source circuit.
- GATE EE - 2026
- Control Systems