DKZ Series Microprocessor-based Controlled High Frequency Switch DC Power Supply System

Introduction

DKZ series microprocessor-based controlled high frequency DC power supply system is one new generation DC power supply device. This device integrates rectifier, voltage adjustment device, DC distribution, protection warning circuit, insulation monitoring, batteries checking and microcomputer monitoring system, realizes automatic management by microcomputer, automatically sets and manages the running of the regular charging, float charging, discharging, constant voltage and constant current charging of various batteries, and makes operations such as automatic voltage adjustment, switch on or off, fault alarm, insulation alarm, signal output, remote control, etc. And also it can realize the function of telemetering, remote supervision, remote adjustment, and remote control by using transmission devices such as Modem, Electric Power Carrier etc, thus realize the remote centralized monitoring management.

Functions

  • The international advanced Three Voltage Level Zero Voltage Switch Resonance Transform technique is adopted in the rectifier module that has the advantages of high efficiency, good electrical feature and electromagnetic compatibility.
  • Fully automatic load sharing N+1 redundant module design is adopted, which enables flexible configuration, convenient capacity expansion and makes the module have perfect self-protective function.
  • Impact resistant: The rectifier module can resist short circuit impact when it works in constant voltage constant current mode.
  • Short circuit resistant: The rectifier module can realize real time protection when the output is in short circuit. Then the output voltage is nearly zero and can hold for a long time. When the short circuit is removed, the rectifier can restore to its normal working status immediately.
  • Power network adaptability: Three-phase input scope is 380V20%. So it can work securely even in unstable power supply areas.
  • Multi thunder protecting system enables the system's secure running.
  • Dual AC input power supply with automatic switch enhances the reliability of the power supply.
  • The rectifier module has perfect protective functions, including AC power off, phase lost, over or under voltage protection, DC output over voltage protection, over current protection, short circuit protection, and over temperature protection.
  • Reverse diode is provided in each module, which enhances system's reliability.
  • Batteries management function: Batteries' Boost or Float charging status can be changed automatically, which can be managed by intelligent monitoring unit or by remote centralized monitoring computers.
  • Intelligent monitoring unit's MMI is convenient and flexible to operate. It can monitor the power network's three-phase AC input voltages, each rectifier module's output current and working status and the DC power busbar, DC control busbar and batteries' voltage and current. It can realize online detection and alarm on the running upper and lower bound of the AC voltage and the DC power Busbar voltage, the DC control Busbar voltage and the battery voltage.
  • Microcomputer battery checking device can detect every unit battery's voltage status, battery group's total voltage, current and AHs (Ampere Hour) of charging and discharging, and realize temperature compensation automatically according to the change of environment temperature and battery's temperature.
  • Microcomputer insulation monitoring unit can on line monitor DC Busbar and each DC distribution insulation resistance and capacitor property, and alarm on low resistance insulation circuit.
  • Provide detailed communication protocol. It can communicate with transformer substation integrated automatic system by RS485 to make up variable network management system, it can also directly connect with PC or modem by RS 232 to make up remote intelligent power network management system, which makes the monitoring software in the network management center manage each power system.

System Description

  • Dual AC input is adopted, and C level thunder-protection device is installed in the module input.
  • Rectifier module adopts N+1 redundant mode configuration, automatic load sharing running.
  • The communication between main monitoring platform and monitoring unit in the system is by RS485.
  • The communication between main monitoring platform and the substation integration automation system is by RS485.
  • The communication between main monitoring platform and the superior platform PC is by RS232.
  • The main monitoring platform can communicate with network management center by Modem.
  • Buck device according to Batteries' property, number and its load.
  • Optional configuration of the lighting, warning switch quantum and batteries monitoring.
  • Insulation monitoring includes DC busbar monitoring, branch monitoring, can optionally configure.

Technical Parameters

  • Three phase input voltage: AC380V20%,50Hz10%
  • Output voltage: 110V system: 90V~160V continuously adjustable
  • 220V system : 180V~320V continuously adjustable
  • Rated output current: 10A~300A continuously adjustable
  • Voltage regulation accuracy:0.5%
  • Current regulation accuracy:0.5%
  • Ripple Voltage :0.1%
  • Regular circuit accuracy:5%
  • Power factor:0.9
  • Effieciency93%
  • Working frequency:100kHz
  • Cooling method: intelligent temperature control, current control wind cooling
  • Adaptable Environment temperature:-10~+45
  • Voltage withstand intension:>2000VAC/50Hz 1 minute, leakage current10mA
  • Noise:45dB

Engineering Application

It has been widely used in large or middle scale hydro-power plants, thermal power plants and 35kV~500kV substations.