KR-20260063704-A - Battery-Based PV Emulator

Abstract

The present invention relates to a battery-based PV emulator, comprising: a battery (200) embedded within the main body of the PV emulator to supply power; a power control unit (310) that generates desired voltage and current values based on power supplied from the battery (200); a main control unit (300) that controls the power control unit (310) based on voltage-power and voltage-current generation data of a PV module according to pre-stored sunlight amount and temperature; and an interface (100) for receiving and transmitting sunlight amount (G) and temperature (T) information to the main control unit (300), wherein the interface (100) further comprises an external sensor unit (110) for directly measuring external sunlight amount (G) or temperature (T) and transmitting it to the main control unit (300).

Inventors

• 정헌

Assignees

• 초당대학교 산학협력단

Dates

Publication Date

20260507

Application Date

20241031

Claims (2)

1. This relates to a battery-based PV emulator, A battery (200) built into the main body of the PV emulator to supply power; A power control unit (310) that generates desired voltage and current values based on power supplied from the battery (200); A main control unit (300) that controls the power control unit (310) based on pre-stored voltage-power and voltage-current generation data of the PV module according to sunlight amount and temperature; and The above-mentioned main control unit (300) includes an interface (100) for receiving and transmitting information on sunlight (G) and temperature (T), A battery-based PV emulator characterized in that the interface (100) further includes an external sensor unit (110) for directly measuring external sunlight (G) or temperature (T) and transmitting it to a main control unit (300).
2. In claim 1, the main control unit (300) includes simulated voltage and current values in a database by assuming a situation where some cells constituting the PV module are not operating normally, A battery-based PV emulator characterized by enabling testing in abnormal operation situations of some cells by testing the PV power converter based on the above database.

Description

Battery-Based PV Emulator The present invention relates to a photovoltaic (PV) emulator used for the development and testing of photovoltaic power generation systems, and more specifically, to a device capable of simulating the electrical characteristics of a photovoltaic module based on a DC power source such as a battery and reproducing the operation of a photovoltaic module in various experimental environments. The present invention is useful in application fields such as testing of power control devices in laboratories, research institutes, and industrial development processes. A photovoltaic (PV) module is a device that receives sunlight and generates electrical energy in real time, and its output voltage and current characteristics vary significantly depending on solar irradiance and environmental conditions. The circuit model of an individual solar cell constituting a PV module is as shown in Fig. 1. Since a single PV module is typically configured by connecting 60, 72, or 92 such solar cells in series, it can be represented by an equivalent circuit model as shown in Fig. 2. It can be understood as an electrical circuit model that simulates the phenomenon where, if a solar cell is obscured by fallen leaves or other foreign substances, the power output of the corresponding constant current source decreases, and the total output current is determined by the current source with the smallest generated current magnitude. Ideally, when developing and evaluating power supplies connected to PV modules, testing should be conducted by irradiating actual PV modules with sunlight or artificial light; however, experiments using actual PV modules make it difficult to control various environmental conditions, and it becomes particularly challenging to perform consistent tests due to changes in weather or solar irradiance. Accordingly, there has been demand for and development of PV emulators capable of simulating the characteristics of photovoltaic modules. Currently, PV emulators enable researchers and developers to test the performance of photovoltaic systems under various conditions and have established themselves as essential equipment for verifying the performance of power generation control systems, inverters, and the like. However, existing PV emulators were systems built on complex electronic circuits, which inevitably led to high manufacturing costs. Furthermore, they only received simulated input values, making it difficult to directly incorporate information such as sunlight levels at the actual solar power system installation site into the emulation. Figure 1 illustrates an equivalent circuit of a cell constituting a PV module, and Figure 2 illustrates an equivalent circuit of a PV module formed by combining multiple cells of Figure 1. Figure 3 illustrates the basic principle of a PV emulator. Figure 4 illustrates the basic configuration of a PV emulator according to the present invention. Figure 5 is a voltage-power curve according to sunlight/temperature. Figure 6 is a voltage-current curve according to sunlight/temperature. The overall configuration of a battery-based PV emulator according to the present invention will be described below with reference to the drawings. Specific structural or functional descriptions presented in the embodiments of the present invention are merely illustrative for the purpose of explaining embodiments according to the concept of the present invention, and embodiments according to the concept of the present invention may be implemented in various forms. Furthermore, it should not be interpreted as being limited to the embodiments described in this specification, but should be understood to include all modifications, equivalents, and substitutions that fall within the spirit and scope of the present invention. In the PV emulator according to the present invention, an external power source is not used, and a DC power source, a battery (200), is used. FIG. 3 illustrates the basic principle of the PV emulator. By controlling the variable impedance (Rs) in the PV emulator, the output voltage (Vpv) and current (Ipv) applied to the power conversion unit (510) are controlled. Since the target output voltage and current generation mechanism itself corresponds to the prior art, a detailed description is omitted. Furthermore, the control of these output voltages and currents is based on voltage/current data according to sunlight amount/temperature that has already been accumulated by the main control unit (300). Specifically, referring to FIG. 4, the configuration of the PV emulator according to the present invention includes a battery module (200) inside the emulator body. The battery module (200) operates as a power supply to simulate the voltage-current characteristics of the PV module and reproduces the power pattern generated by the PV module. The main control unit (300) has a built-in control algorithm for accurately simulating the voltage and current characteristics of the