Product Usage

It is mainly used in power plants, hydropower stations, various substations, switching stations, and user transformers to provide DC power for circuit breaker opening, closing, and control, signaling, protection, telecontrol communication, and fault lighting in the secondary circuit. It is used in fields such as electric power, petroleum, chemical engineering, metallurgy, machinery, paper making, building materials, textiles, brewing, etc.

Product composition

AC power distribution unit

Monitoring system module

Voltage regulating silicon chain module

Insulation monitoring module

High frequency switch rectifier module

Battery monitor

Battery pack

Feed unit

Principle and function of each component

AC power distribution unit: The AC system of the DC panel generally has two AC power inputs. Normally, the AC power input switch is set to the "automatic" position, with one circuit in operation and two circuits for standby. The AC power is sent to each charging module through the AC input air switch, AC contactor, lightning arrester, etc., to provide AC power for the high-frequency switch rectifier module.

Monitoring system module: The monitoring system for the DC screen is a human-computer interface with an LCD display. It serves as a bridge between the underlying module and background management, and is the brain of the DC screen. It is responsible for managing the charging module and the underlying automatic battery management, viewing current fault information, historical information records, and various parameters.

Voltage regulating silicon chain module: When the DC power supply system equalizes the charging of the battery pack, the output voltage of the charging module will be higher than the rated voltage of the control circuit. At this time, a voltage regulating device is required to adjust the voltage to supply power to the bus control circuit. The silicon chain module is such a voltage regulator that can automatically and manually change the voltage to ensure that the voltage of the control bus is within the range.

The step-down silicon chain unit uses the PN junction forward voltage drop superposition of high-power rectifier diodes to generate a regulated voltage drop. This method is reliable, has good impact resistance, and is easy to maintain.

Insulation detection module: used to monitor the DC system voltage and its insulation condition. In the event of abnormal conditions such as a decrease in insulation strength in the DC system (typically lower than 25K Ω for 220V DC voltage systems, and lower than 7K Ω for 110V DC voltage systems), an audible and visual alarm is issued, and the corresponding branch number and resistance value can be found.

High frequency switch rectifier module: The high frequency switch rectifier module is the heart of the DC screen and is responsible for providing power to the DC screen. On the one hand, it charges the battery, and on the other hand, it provides normal working current to the DC load. There is a monitoring board inside the charging module that can monitor and control the operation of the module. Since the charging module itself has a CPU, the charging module can also operate independently of the monitoring module.

Battery pack: As a backup power supply for the DC system of the entire station, when the charging module stops working, the battery continuously transmits power to the DC bus; In addition, during the closing operation of the electromagnetic circuit breaker, the closing current is greater than 100A, and the battery becomes the closing power supply. It is equivalent to a storage organization, which is the warehouse of the entire DC screen. As everyone knows, AC power cannot be stored, so the DC screen uses a battery pack to convert the DC power converted from the module into chemical energy, and when the AC power outage occurs, the chemical energy is converted into electrical energy to supply power to the DC load.