HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 42
CHAPTER 7
RESULTS AND DISCUSSIONS
This chapter discusses about the results obtained from simulation of solar panel,
high step up DC-DC converter along with PID controller, interleaved high step up DC-
DC converter with PID controller.
7.1 SIMULATION RESULT OF SOLAR PANEL
In this section the simulation results of solar panel is discussed. The Fig 7.1 shows
the solar panel output voltage.
Figure 7.1 solar panel output voltages.
The x axes represents time is seconds and y axes represents voltage in volts. The red color
line represents solar panel output voltage. From the Fig 7.1 it is observed that output of
solar panel is constant 15 volt dc voltage.
7.2 SIMULATION RESULTS OF HIGH STEP UP DC-DC
CONVERTER
In this section the simulation results of high step up dc-dc converter is discussed. The
electrical specifications of high step up dc-dc converter are as follows.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 43
Vin = 15 V,
Vo = 200 V,
Fs = 50 kHz,
RL = 1000Ω.
C1 = C2 =47µF, C3 =220µF.
N = 5,
D = as 55%
Figure 7.2 Input voltage of high step up dc-dc converter.
The Fig 7.2 shows the input voltage of high step up dc-dc converter. The x axes
represents time is seconds and y axes represents voltage in volts. The red color line
represents input voltage. From the Fig 7.2 it is observed that input to the converter is
constant 15 volt dc voltage.
Figure 7.3(a) voltage and current across Diode D1.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 44
Figure 7.3(b) voltage and current across Diode D2.
Figure 7.3(c) voltage and current across Diode D3.
Figure 7.3(d) voltage across switch S1.
Figure 7.3 voltage and current across diode d1, d2, d3 and S1.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 45
Voltage across diodes and switches can be calculated from equations (4.19) and (4.20)
The currents and voltage waveforms across the diodes D1, D2 & D3 are shown in
Fig.7.3 From Fig. 7.3(a), it is observed that voltage across diode D1 is 200 volt and
current is 8 ampere Similarly, from Fig.7.3 (b) it is observed that the voltage across diode
D2 is 100 volt and current 3 ampere and from Fig 7.3(c) it can observe that voltage across
diode D3 is 100 volt and current 3 ampere. From Fig 7.(d) it can observe that voltage
across switch S1 is 200 volt
Figure 7.4(a) voltage across capacitor C1
Figure 7.4(b) voltage across capacitor C2
Figure 7.4 voltage across capacitors C1 and C2.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 46
Voltage across capacitors can be calculated from equations (4.13) and (4.14)
The voltage waveforms across the diodes C1 and C2 are shown in Fig.7.4 from Fig.
7.4(a), it is observed that voltage across capacitor C1 is 200 volt similarly; from Fig.7.4
(b) it is observed that the voltage across capacity or C2 is 12 volt.
Figure 7.5 Output voltage of high step up dc-dc converter.
The Fig 7.5 shows output voltage on y axes and time on x axes. From the Fig 7.5 it is
observed that 15 volt dc input voltage to the converter has been stepped up to 200 volt dc
output voltage and it also observed that rise time (tr) of the voltage 0.4 seconds
The voltage gain can be calculated by the equation given below
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 47
The efficiency of the converter can be calculated by the equation given below
The simulation results of high step up dc-dc converter with the electrical specifications
Vin = 7 V, Vo = 105 V, Fs = 50 kHz, RL = 1000Ω. C1 = C2 =4.7µF, C3 =1µF. D = as
55%.
Figure 7.6 voltage and current across diode d1, d2, d3 .
The voltage waveforms across the diodes D1, D2 & D3 are shown in FIG 7.6 .From
FIG 7.6 it is observed that voltage across D2 and D3 is 20 and is justified from equation
(4.19&4.20). It is observed from equation that voltage across diode D1 is 70 volt
similarly, the voltage across diode D2 is 20 volt and voltage across diode D3 is 35 volt.
The justification for output voltage can be given by equation (4.17). It is observed that 7
volt dc input voltage to the converter has been stepped up to 103 volt dc output voltage.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 48
Figure 7.7 Output voltage of high step up dc-dc converter.
The Fig 7.7 shows output voltage on y axes and time on x axes. From the Fig 7.7 it is
observed that 7 volt dc input voltage to the converter has been stepped up to 105 volt dc
output voltage and it also observed that rise time (tr) of the voltage 0.02 seconds.
The voltage gain and efficiency can be calculated by the equation given below.
From voltage gain and efficiency of high step up dc-dc converter it is observed that
without extreme duty ratios and the numerous turns-ratios of a coupled inductor, this
converter achieves a high step-up voltage-conversion ratio and they is very low ripple
content in the output.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 49
7.3 SIMULATION RESULTS OF HIGH STEP UP DC-DC
CONVERTER WITH PID CONTROLLER
In this section the simulation results of high step up dc-dc converter with PID
controller is discussed. The electrical specifications of high step up dc-dc converter are
Vin =15 V, Vo=200 V, Fs=50 kHz, and full load resistance R=1000Ω. The major
components required are C1 = C2 =47μF and C3 =220μF. The main switch S1 is a
MOSFET turns ratio n=5, the duty ratio D is derived as 55%.
Figure 7.8 Converter input voltage.
In Fig 7.8 x-axes represents time and y-axes represents voltage. It shows that 15 volt
constant dc input voltage is given to the converter.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 50
Figure 7.9(a) voltage and current across Diode D1.
Figure 7.9(b) voltage and current across Diode D2.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 51
Figure 7.9(c) voltage and current across Diode D3.
Figure 7.9(d) voltage across switch S1.
Figure 7.9 voltage and current across diode d1, d2, d3 and S1.
Voltage across diodes and switches can be calculated from equations (4.19) and (4.20)
The currents and voltage waveforms across the diodes D1, D2 & D3 are shown in
Fig.7.9 From Fig. 7.9(a), it is observed that voltage across diode D1 is 200 volt and
current is 8 ampere Similarly, from Fig.7.9 (b) it is observed that the voltage across diode
D2 is 100 volt and current 3 ampere and from Fig 7.9(c) it can observe that voltage across
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 52
diode D3 is 100 volt and current 3 ampere. From Fig 7.9(d) it can observe that voltage
across switch S1 is 200 volt.
Figure 7.10(a) voltage across capacitor C1
Figure 7.10(b) voltage across capacitor C2
Figure 7.10 voltage across capacitors C1 and C2.
Voltage across capacitors can be calculated from equations (4.13) and (4.14)
The voltage waveforms across the diodes C1 and C2 are shown in Fig.7.10 from
Fig. 7.10(a), it is observed that voltage across capacitor C1 is 200 volt similarly; from
Fig.7.10 it is observed that the voltage across capacitor C2 is 12 volt.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 53
Figure 7.11 Converter output with and without PID controller
The Fig 7.11 shows output voltage on y axes and time on x axes. In Fig 7.11 the
blue line represents the converter output with PID controller and red line represents
without PID controller .From the Fig 7.11 we can say that 15 volt dc input voltage to the
converter has been stepped up to 200 volt dc output voltage and it can be observed that
rise time (tr) of the voltage without PID controller is 0.4 and with pid controller it is 0.15.
TABLE 7.1
Converter output comparison
Converter output Without PID controller With PID controller
Rise time 0.4 0.15
Steady state error 2v 0.2v
The table 7.1 shows the converter output comparison with and without PID
controller .from table 7.1 it is observed that converter without PID controller has rise time
of 0.4 seconds, steady state error of 2V volts and converter with PID controller has rise
time of 0.15 seconds, steady error of 0.2v.So it can concluded that converter with PID
controller has less rise time and steady state error compared to without PID controller.
The voltage gain and efficiency can be calculated by the equation given below.
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 54
From voltage gain and efficiency of high step up dc-dc converter with PID
controller it is observed that without extreme duty ratios and the numerous turns-ratios of
a coupled inductor, this converter achieves a high step-up voltage-conversion ratio; the
leakage inductor energy of the coupled inductor is efficiently recycled to the load and
they is very low ripple content in the output.
7.4 SIMULATION RESULTS OF INTERLEAVED HIGH
STEP UP DC-DC CONVERTER WITH PID CONTROLLER
In this section the simulation results of interleaved high step up dc-dc converter
with PID controller is discussed. The electrical specifications of interleaved high step up
dc-dc converter are as follows Vin =15 V, Vo=250 V, Fs=50 kHz, and full load resistance
R=1000Ω. The major components required are C1 = C2= C3=C4=47μF and C5 =220μF.
The main switch S1, S2 is a MOSFET turns ratio n=8, the duty ratio D is derived as 55%.
FIG 7.12 shows the voltage across diodes D1, D2, D3, D4.The x axis represents
time in seconds and y axis represents voltage in volts. From Fig 7.12 it can observed that
voltage across diode D1, D3 is 240v and voltage across diode D2, D4 is 80v.Voltage
across the diodes can be calculated from equations (4.19) and (4.20)
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 55
Figure 7.12 voltages across diode D1, D2, D3, D4.
Figure 7.13 voltages across capacitors C1, C2, C3, C4.
FIG 7.13 shows the voltage across capacitors C1, C2, C3, and C4. The x axis
represents time in seconds and y axis represents voltage in volts. From Fig 7.13 it is
observed that voltage across capacitors C1, C3 is 240v and voltage across capacitor C2,
C4 is 9v.Voltage across the capacitors can be calculated from equations (4.13) and (4.14).
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 56
Figure 7.14 Output voltage of proposed converter
FIG.7.14 shows the output voltage of the proposed converter. The x axis
represents time in seconds and y axis represents voltage in volts. From Fig 7.14 it can
observe that output voltage of proposed converter is 250V.The voltage gain and
efficiency can be calculated by the equation given below.
=
HIGH VOLTAGE GAIN, HIGH STEP UP DC-DC CONVERTER
MTECH, EPE, DSCE BANGALORE 57
Thus it is observed from above equation without extreme duty ratios and the numerous
turns-ratios of a coupled inductor, this converter achieves a high step-up voltage-
conversion ratio; the leakage inductor energy of the coupled inductor is efficiently
recycled to the load and they is very low ripple content in the output .
7.5 HARWARE RESULTS OF PROPOSED CONVERTER
In this section the hardware results of high step up dc-dc converter is discussed.
The electrical specifications of high step up dc-dc converter are Vin = 7 V, Vo =105 V,
Fs = 50 kHz, RL = 1000Ω. C1 = C2 =4.7µF, C3 =1µF.N = 5, D = as 55%.
Figure 7.15 Gate pulses to switch S1.
Fig 7.15 shows the gate control signals to the switch S1.The switching frequency is
50 kHz and it operates at 0.5 duty cycle as shown above.
Figure 7.16 Voltage across diode D2, D3.