Home-made rogowski coil

Part 1: Power Amplifier Circuit First we built power amplifier circuit. According to the instruction book, we knew we need to used two 1000 μF capacitors connected with power amplifier. Then we inserted a resistor to measure the output signal. According to the instruction book of power amplifier, it requires a symmetric DC power supply with an output range of 30 to 35V. In the experiment we provided a 30V DC power supply.  After testing the power amplifier circuit, we put current transducer into the circuit but the result was incorrect. We decided to finish this part in next week. Part 2: Theoretical voltage of coil We estimated the ratio of number of turns to length 1cm. The estimated result is 21 turns per centimeter, so N/L=2100 (turns per meter). Then we measured the coil diameter by electronic digital caliper is 2.4mm so r=1.2mm. In the experiment, the signal frequency we used was 50kHz. The calculation of coil theoretical voltage is following: ...

Part 1:  Re-construct integrator circuit & connect power amplifier circuit  This week we re-constructed our integrator circuit to get a correct output voltage waveform . The circuit diagram was the same as previous diagram.  We used computer to calculate and get a suitable value of resistor and capacitor we use. According to the calculation result we drew a linear relationship diagram of the gain and frequency. We found that if Rc is too small, the output waveform will distort, if the capacitor is too small, the capacitance will have slightly influence on the output signal. Then we need to make Rc lagger than R, so we chose Rc=330k, R=10k ohm and C=10nF. The problem was that when we only provide a square wave input signal to the general amplifier, the output waveform was normal and we got a waveform which was accord with expected shape. However, when we provided both square wave input signal and a DC 5V voltage to the amplifier, the input signal kept...

Part 1: Build Integrator Circuit This week we continued to build the integrator circuit because last week our circuit existed problems. The following is the circuit we design and the real circuit we built. The input voltage is a 50kHz square wave. R3=10k ohm, R=10k ohm and we changed the value of capacitance and resistance.  At first, we found no matter we changed the capacitance or resistance, the output waveform kept unchanged. We checked our circuit, input signal and the set of digital oscilloscope but found no error that lead to the wrong output. We spent a lot time in checking mistakes and finally we found that we forgot to provide a DC input voltage to active the amplifier. We provide a 5V DC input voltage, then the circuit worked normally. First, we set Rc=330k ohm and C=10nF.  Part 2: Problems in Output Waveform   We kept Rc=330k ohm unchanged, then changed the value of capacitor from 10nFto 0.2 μF. We found that the big change of capacitan...

Part 1: Preparations before the lab After getting all of the experiemnt components, the first step we did was to check the modle type of every components and search their properties and usage in the global circuit. We set a primary image of the rogowski coil circuit by looking up online materials and the circuit we decided to use is like: We dicided to wind the coil but we did not find a suitable material to wind it. Then we dicided to build the integrator circuit first. The integrator will be used to integrate the voltage generated by the coil in the global circuit. Part 2: Build the integrator circuit The following is our disigned circuit diagram and we built the integrator circuit according to the diagram. We chose several 10k ohm resistors and a 330k ohm resistor. The capacitor we used was 10nF, 100nF. The input AC voltage was 50kHz, 3V square waveform and DC input is 5V.  This is the circuit we built. We changed the resistance, capacitance and...