PV educator

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We can perform the simulation in following steps.

1. Design the circuit.
2. Choose the switch from Analog_Misc>Swt_close/open.
3. Choose from the Special>PARAM and place it with the layout.
4. Right click on the resistance and add the value as {OHM}.
5. Double click on the parameter and add new property and name it OHM and value 1. This is the initial value.
6. Click on PSPICE > Edit simualtion Profile > Paramteric sweep > Global parameter (parameter name Ohm) Then add the initial final and increment value.
7. Simulate the circuit.
8. You can double click on the legend near the bottom left to see the value of the parameter swept in the analysis

The output of the rectifier was not sinusoidal. It was like the one shown below.



Then i found the problem in  the .tran command. The script of the .tran command is

tran <tstep> <tstop> <tstart> <tmax>

In this synax the parameters are as follows

The following circuit is used to plot the power vs the load resistance curve.

The PSPICE script is as follows.

MPTT grapgh
V1 1 0 DC 10
Rt 1 2 20
Vx 2 3 DC 0
RL 3 0 RMOD 1
.MODEL RMOD RES(R=1)
.STEP RES RMOD(R) 1, 100, 1
.DC V1 20 20 1
.PRINT DC V(1,2) I(RL)
.probe
.end

The resultant plot as a function of RL is shown below.

Solar PV cells are the smallest unit in a PV panel. These are low power output units and hence in order to produce a reasonable output from them, several cells are connected in series and parallel configurations. In a series and parallel configuration, we use to add a bypass diode that prevents the sinking of a group of cells in case of shading. This blocking diode is always connected across a group of cells because of two reasons. First, no ideal diode exists which means that diodes need to overcome a potential difference to work. Secondly, in a single cell, it is very difficult to forward bias the diode because of very low output voltage levels. 

Figure 1 : Schematic. PV module consists of 5 X 2 cells

Figure 2: Under uniform irradiance condition

Figure 3 : Partial shading on three cells of module 1.

Figure 4. Code for PSPICE

In PSPICE plotting is not based on programming like that in MATLAB. In fact, the plotting is based on the set of variables that can be selected for x and y axis. The problem, however, is that if you want to plot two curves with different ranges of x axis variables.  I spent quite a time on solving this issue. Although I did not reach where I wanted to land, however, i found one solution but first, let me introduce you to the circuit i wanted to simulate.
The figure above shows two PV cells connected in series with each other. The combined output is taken from the node 3 and 5. I want to draw the I-V curves of both the cells as well as their combined output. However, in order to do so if I select the x axis as the voltage V3 the I-V curve for the individual cells is compromised and if I select the x axis as V3-V1 then the I-V curve of combined cells is compromised. To solve this I selected two plots and unsynchronized their x axis as shown in the figure below. To unsyncronize the x axis click on plot > unsynchronize x axis.


The next challenge is to plot them on one plot. 

Introduction to spice by PhD EE on Scribd

Pspice Phase 2 

Pspice Workshop Phase-1

A Maximum power point tracking (MPPT) system is essential for enhancing the efficiency of the PV system. There are various algorithms for the MPPT system that includes the traditional hill climbing MPPT, AI based MPPT and fixed voltage based algorithms. The testing of these algorithms is important to evaluate their performance under various kinds of environmental conditions. In the research community following are the test conditions applied on the MPPT system for its evaluation.

1. Standard testing condition. The MPPT system is provided a standard testing condition of a PV module with 1000 W/m²  irradiance and temperature of 25 C.
2. Step change in irradiance: To simulate the behavior of MPPT under dynamic weather condition the environmental parameters are changed in step mode. Usually irradiance is changed because in reality the change in temperature is slow. So the irradiance is changed from say 1000 W/m² to 500 W/m² and then to 200 W/m² . This step change evaluates the system response under abrupt changes. It is pertinent to mention that in this testing condition not only the step change is applied in decreasing fashion but can also be applied in increasing mode i.e at starting from 500 W/m²  to 1000 W/m²  with step values of 100 or 50 or whatever. The step change increment and decrements are two different things and the algorithms particularly the hill climbing behaves differently. Therefore, the MPPT must be tested for both increasing irradiance as well as for decreasing irradiance. 

   Condition 2 for the testing of four different MPPT methods

3. The environmental conditions are changed gradually in ramp function. This testing condition simulates the normal weather condition with sunlight increasing linearly from sunrise to noon and then stays constant for few hours and then begins to descend in the same manner.
4. Another weather condition can be simulated by merging point 2 and 3 to have a normal day scenario with abrupt changes in between. This simulates the birds or some building shade on the PV panel.

Condition 4

Note : If you are using a variable step size in simulink, then add a zero order hold before each input of sim coupler and insert the sample time same as of PSIM. If you are using fixed step size in simulink then