Home > Solution> Solar PV Design Principle and Method> Simulation Method

Hot Product

51-52 Solar Power Generation System DC-DC Converter

Author: Source: Datetime: 2016-12-24 11:44:58
DC-DC converter

DC-DC changes are often used to deal with solar panels and DC load and the battery between the match. Figure 3-9 shows the DC-DC converter and the battery connected to the input and output relations. When the lead-acid battery discharge, the electrical energy from the battery through the DC-DC converter out, and this time the battery becomes the DC-DC converter input. Basically the same as the inverter, DC-DC converter mathematical model can be reduced to reactive loss and input current loss and output current loss. The equivalent circuit is shown in Figure 3-10.


Figure 3-9 DC-DC converter and battery


Figure 3-10 DC-DC converter equivalent circuit

Linked input and output relationships

IDDout=PDDinηDD/VDDout                                                                (3-56)

PDDout=PDDin-LODD-RDDinI2DDIN-RDDoutI2DDout                                        (3-57)

IDDin=PDDin/VDDin                                                                         (3-58)

ηDD=PDDout/PDDin                                                                        (3-59)

PDDout=VDDoutIDDout                                                                       (3-60)


VDDin                    DC-DC converter input voltage
IDDin                     DC-DC converter input current
PDDin                    DC-DC converter input power
VDDout                        DC-DC converter output voltage
IDDout                   DC-DC converter output current
PDDout                  DC-DC converter output power
ηDD                      DC-DC converter efficiency
LODD                    DC-DC converter reactive power loss
RDDin                   DC-DC converter equivalent input impedance
RDDout                  DC-DC converter equivalent output impedance

The reactive power loss of the converter, regardless of whether the load is a certain number. The current loss is divided into two parts: input and output. When the DC-DC converter with high power tracking control is used, the input voltage in its operating voltage range is consistent with the operating voltage of the maximum power point of the solar panel; at the maximum output power, The human current is the current at the maximum power point of the solar panel. When the deviation from the operating voltage range, we must calculate the voltage and current balance of the operating point. For the load terminal, it is necessary to pay attention to the control corresponding to the load change when connecting with the load. For example, when the output voltage is controlled, the rabbit output voltage can be treated as an invariant value. When connected to the battery, the output voltage is the same as the end voltage of the battery.

Diesel generators

In the diesel generator simulation, it can be considered that the diesel generator terminal voltage is approximately constant value. This is because the Chaowai generator governor and exciter, etc. with a voltage regulator function.

In the calculation of the cost of diesel generators, diesel generators to know the fuel consumption. However, the catalogs on the market are mostly fuel consumption of diesel generators at rated power, and the fuel consumption per unit output under various load conditions is not described. For small units, because the fuel consumption and the load is not, can be rated power per kilowatt fuel consumption calculation, and for the power of 100kW or more units, it is necessary through the relevant diesel generator technical information, Confirm the fuel consumption under various load conditions.

TAG: Duke 100Ah 48V telecom Malta Battery-Box Passenger NTPC Containerized Off-Grid Code Building California Korean SolarEdge