Question

an experimental study is conducted to compare edm performance between rc circuit and transistor-based generator under the same individual pulse discharge energy (e d) and cycle frequency of 6.25 khz. the workpiece is hardened steel and the dc power supply is 240 v. (1) in transistor-based generator, the duty factor is set 0.5 and the measured discharge voltage and current are 30 v and 80 a, respectively. what is the individual pulse discharge energy (ed)?

Answer 1

The individual pulse discharge energy (E_d) can be calculated using the formula:

E_d = 0.5 * C * V^2

where C is the capacitance and V is the voltage.

Since the duty factor is 0.5, the discharge time (t_d) is equal to the period (T) divided by 2:

t_d = T / 2 = 1 / (2 * f) = 1 / (2 * 6250) = 8 × 10^-5 s

The capacitance can be calculated using the formula:

C = I * t_d / (V - V_f)

where I is the current, V is the discharge voltage, and V_f is the forward voltage drop of the diode.

Assuming a diode forward voltage drop of 0.7 V, we can calculate the capacitance:

C = 80 * 8 × 10^-5 / (30 - 0.7) = 0.000281 F

Now we can calculate the individual pulse discharge energy:

E_d = 0.5 * C * V^2 = 0.5 * 0.000281 * 30^2 = 0.038 J

Therefore, the individual pulse discharge energy (E_d) is 0.038 J.