Power tube protection and high-efficiency output method of a DC current source

Abstract

The invention discloses a power tube protection and high-efficiency output method of a DC current source, which mainly includes using a voltage source whose output voltage can be continuously adjusted as the power source of the current source; Current size, set the output current value Ib, and preset the power supply voltage value Up, and start to output current; after the current source starts to work, the main control module automatically detects the voltage Ub on the power tube, and calculates the power consumption on the power tube Wb= Ub*Ib; Determine the best power consumption range W1-W2 of the power tube according to the data sheet of the power tube and experiments; whether the main control module determines whether the power consumption Wb on the power tube is in the best working range of the power tube. The invention can automatically detect the loss of the power tube, keep the loss of the power tube in a constant range, and greatly improve the output efficiency of the DC current source, so that high-efficiency output of high power and high Voltage, high current, and reliable protection of the power tube.

Description

technical field [0001] The invention relates to the field of programmable direct current source, more specifically, relates to a power tube protection and high-efficiency output method of the direct current source. Background technique [0002] Due to the rapid development of the global LED industry, countries have introduced some testing standards for LEDs, and users have higher and higher quality requirements for LEDs. Therefore, LED aging and service life tests are also developing rapidly. To conduct accurate power aging and life tests on LEDs, the basic requirement is that the aging test of each LED must be an independent current. The demand for multi-channel (more than 100 channels) DC current sources has also increased significantly. However, due to the limitations of equipment size and cost, it is impossible for this multi-channel DC current source to use a large-volume heat sink in each current loop for heat dissipation, resulting in the output power, voltage, and c...

AI Technical Summary

Problems solved by technology

[0006] 1. The output efficiency of the current source is low. When the load power is small, the output power of the power supply is mainly borne by the power amplifier tube, resulting in huge heat loss

[0007] 2. In the current power tube protection scheme, limited by the cost, the thermistor is mainly used to detect the temperature of the power tube, and the thermistor is highly discrete, affected by the ambient temperature, the detection is inaccurate, and often malfunctions;

[0008] 3. The thermal detection element must be as close as possible to the power tube to have a better effect, and the installation and production process is relatively high;

[0009] 4. When the power required by the load changes, since the output voltage of the power supply is constant, if the voltage required by the load is small, the power tube needs to withstand a higher voltage. In the case of a large output current, the power loss on the power tube The sharp increase will seriously affect the size of the output power and limit the scope of use of the power supply

[0010] 5. In order to expand the application range of the power supply to the load as much as possible, the temperature value of the thermal protection is generally designed to the upper limit of the temperature that the power tube can withstand. In the actual use process, the loss on the power tube changes according to different loads. It cannot be guaranteed to be in a constant interval, which leads to constant changes in the temperature of the power tube, and during the temperature change process of the power tube, its related parameters change non-linearly, which seriously affects the various technical parameters of the current source output

[0011] 6. The volume and weight of the equipment are relatively large, so it is not suitable to be designed as a multi-channel DC current source

Images