Broadband digital power line carrier machine

The QL-101 3000 Broadband Digital Power Line Carrier (DPLC) System is a remote communication device designed to utilize high-voltage (HV) transmission lines. It is widely used in power dispatch, protection, and power automation communication. The QL-101 3000 offers a comprehensive range of user interfaces, covering nearly all communication services required by substations. These services include various RTU digital signals, remote Ethernet, video, telephone, and both digital and analog protection signal transmission.

Description

Product Introduction

The QL-101 3000 broadband digital power line carrier (DPLC) system is a remote communication equipment designed to use high-voltage (HV) transmission lines. It is widely used in power dispatching, protection, and power automation communication. The QL-101 3000 integrates a rich user interface that covers almost all communication services required for substations, including RTU digital signals, remote Ethernet, video, telephone, and digital and analog protection signal transmission. This versatility has earned it the name “Universal Power Line Carrier.”

The QL-101 3000 supports digital communication speeds from 0 to 384 kbps, with a transmission bandwidth selectable by the user from 4 to 48 kHz. Voice, asynchronous digital channels, and remote Ethernet are multiplexed through an OFDM modem via a built-in statistical time division multiplexer. All performance indicators comply with the latest Chinese standard GB/T7255-1998 “Unilateral Power Line Carrier Machine” and international standards IEC60870-5-104 and IEC-495ITU.

Main Performance

  • Carrier Modem Module Connection: Based on the E1 interface, supporting almost all PCM terminal user interface types, effectively combining a carrier head with a PCM terminal.
  • High-Frequency Band Utilization: Supports 32 kbps per 4 kHz bandwidth, achieving up to 384 kbps for 48 kHz, significantly higher than traditional digital carrier rates.
  • Mixed OFDM and Analog Channels: Supports mixed channels in the same device with an analog channel delay of <6 ms.
  • Built-in Statistical Time Division Multiplexer: Serves various voice and asynchronous digital channels, supporting up to 32 data or telephone channels.
  • Single-Sideband Multi-Carrier Modem (SSB-OFDM): High resistance to uneven line frequency response and single-frequency interference.
  • Extended Carrier Center Frequency: Up to 1000 kHz, with transmission bandwidths ranging from 4 to 48 kHz.
  • Real-Time Dynamic Rate Adjustment (RDSA): Adjusts data transmission rate as needed without interrupting transmission or generating errors.
  • Dual Power Supplies: Provides mutual heating and automatic hot-swapping for increased redundancy and reliability.
  • PC-Based Monitoring Software: Offers a user-friendly interface for easy learning and control.
  • Built-in Protection Channel Terminal (TPT-100): Features coded transmission of eight independent protection commands and pulse interference suppression technology.

Scope of Application

The QL-101 3000 integrates almost all communication channels required for power communication, ensuring future-proof investment for users.

Figures

  • Broadband Carrier Service:

  • Remote Terminal Machine Extension:

  • Integration with Optical Fiber Networks:

 

Standards Compliance

  • IEC495-1993: Single-sided carrier machine with power line.
  • GB/T7255-1998: Single-sided carrier machine with power line.
  • IEC 801-3: Electromagnetic radiation.
  • IEC 801-4: Pulse interference.
  • DL/T1124-2009: Digital Power Line Carrier Machine.

Technical Parameters

System

  • Carrier Transmission Modulation Mode: Single sideband (SSB), multi-carrier (OFDM), quadrature amplitude modulation (QAM).
  • Transmission Frequency Range: 40-1500 kHz.
  • Transmission Frequency Bandwidth: 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48 kHz.
  • Frequency Interval:
    • Native transceiver: 0B.
    • Sent to neighboring transmission: 3B.
    • Sent to neighboring reception: 1B.
    • Received to neighboring reception: 0B.
  • Real-Time Dynamic Rate Adjustment.

Output Power

  • Output Power: 40, 80W.
  • Output Impedance: 50 or 75 ohms unbalanced, 100 or 120 ohms balanced.
  • Output Attenuation: ≥60dB/≥70dB outside the 1BN/2BN frequency band (1BN = 4 kHz).

Sensitivity and Selectivity

  • Sensitivity to Pilot Reception: -40dBm (varies with operating mode).
  • Pilot Selectivity: Attenuation ≥65dB/≥75dB.
  • Automatic Gain Control (AGC): 40dB dynamic range outside the 1BN/2BN frequency band.

Transmission Capacity

  • 8 kHz Bandwidth: Max 64 kbps.
  • 32 kHz Bandwidth: Max 256 kbps.
  • 48 kHz Bandwidth: Max 384 kbps.
  • Signal-to-Noise Ratio (S/N):
    • 36dB: 8 bit/s/Hz (equivalent to 32 kHz bandwidth 256 kbps).
    • 20dB: 4 bit/s/Hz (equivalent to 8 kHz bandwidth 32 kbps).

System Alarm Output

  • Alarm Output: 4 relay air contacts.
  • Switching Voltage: Max 220VDC.
  • Switching Current: Max 2ADC.

Maintenance Interface

  • Basic Interface: RS232 115.2kbps.

Environmental Conditions

  • Operating Temperature Range: 0°C to +55°C.
  • Storage and Transportation Temperature Range: -40°C to +70°C.
  • Relative Humidity: 5 to 95%.

Power Consumption

  • Input Voltage: 48VDC.
  • Power Consumption: Less than 25W (without power amplifier).

Voice Interface

  • Voice Compression Coding: G.723.1 standard, 5.3 kbps or 6.3 kbps.
  • Built-in Program-Controlled Switch (PBX): 32X32 non-blocking switching.
  • Signal: DTMF.
  • Line Echo Cancellation: Optional.

4-Wire E&M Interface

  • Maximum Number of Interfaces: 12.
  • Input/Output Impedance: 600 ohms balanced.
  • Input Level Range: -17dBm to +1dBm.
  • Output Level Range: -7dBm to +14dBm.

2-Wire FXS Interface

  • Maximum Number of Interfaces: 16.
  • Input/Output Impedance: 600 ohms.
  • Loop Current: 48V/max. 40mA.
  • Loop Impedance: ≤1500 ohms.
  • Bell Current: 90Vpp, 25Hz.
  • Input Level Range: -17dBm to +4dBm.
  • Output Level Range: -17dBm to +1dBm.

2-Wire FXO Interface

  • Maximum Number of Interfaces: 16.
  • Input/Output Impedance: 600 ohms.
  • Bell Current Detection: 20130Vrms, 1760Hz.
  • Loop Impedance: <560 ohms.
  • Loop Maximum Current: 70mA.
  • Input Level Range: -17dBm to 3dBm.
  • Output Level Range: -17dBm to 0dB.

E1 Interface

  • Maximum Number of Interfaces: 2.
  • Maximum Number of Voice Channels: 15 (64 kbps, E1).
  • Data Rate: 2.048 Mbps.
  • Input/Output Impedance: G.703.6 standard, 75 ohms unbalanced, 120 ohms balanced.

Digital Interface

  • Maximum Number of Interfaces: 2.
  • Center Frequency: 500 to 3500Hz.
  • Frequency Bandwidth: 1000, 1500, 2000, 2500, or 3000Hz.
  • Transmission Delay: <6ms.
  • AGC: 50dB dynamic range, voice output level stability <±0.5dB.

FSK Modem Card

  • Maximum Number of Interfaces: 12.
  • Data Transmission Rate: 300, 600, 1200 bps.
  • Interface Type: Voice FSK Modem or RS232 interface.
  • Center Frequency: 400~3600Hz, accuracy 1Hz.

Data Interface

  • Maximum Number of Interfaces: 16.
  • Asynchronous RS232 Interface Signal: TxD, RxD, RTS, CTS.
  • Bit Rate: 1.2, 2.4, 4.8, 9.6, 19.2, 38.4, 57.6, 115.2 kbps (transparent asynchronous transmission).
  • Synchronous V.35, V.11 (RS-422, 449), X.21: Bit Rate: 9.6 to 64 kbps.
  • Sibu G703.1 Interface: Bit Rate: 64 kbps, input and output impedance 120 ohms balanced, G703.1.

Ethernet Port

  • Speed: 10 TX.
  • Bandwidth: Max. 360 kbps.
  • Support: Layer-2 bridge, IP routing.

Remote Protection

  • Transmission Channel: Four-wire voice frequency remote protection channel.
  • Maximum Number of Channels: 2.
  • Input/Output Impedance: 600 ohms balanced.
  • Input Level Range: -30dBm to +3dBm.
  • Output Level Range: -30dBm to +3dBm.
  • Transmission Delay: ≤4ms.
  • Digital Channel: Digital V.35, G703.1, 64 kbps, or G703.6, E1.

Built-in Protection Command Terminal TPT-100

  • Performance Mode: Blocking type (Blocking), permitting type (PTT), direct jump type (DTT).
  • Number of Commands: Max. 8 independent commands with ≥4 kHz bandwidth.
  • Modulation: F6 modulation or FSK coding modulation.
  • Event Recording: Up to 24K protection records with time markers in non-volatile devices.
  • Clock Interface: IRIG-B.

Command Input

  • Nominal Input Voltage: 24, 48, 110, 220 VDC.
  • Voltage Range: 50~70% of the nominal input voltage.
  • Trigger Mode: Voltage trigger.
  • Voltage Polarity: No.
  • Trigger Anti-False Delay: 0.125ms, supports 50ms (accuracy 0.125ms).

Command Output

  • Output Mode: Solid state relay or mechanical relay.
  • Contact Voltage: Max. 280 VDC.
  • Contact Current: Solid state relay max. 1A (3A/10ms), mechanical relay max. 5A (20A peak).
  • Isolation Voltage: 2.5 kV RMS.
  • Nominal Transmission Time:
    • Locking Type: <10ms.
    • Permitting Type: <11ms.
    • Direct Jump Type: <12ms.
  • Safety (Puc):
    • Locking Type: <1E-04.
    • Permitting Type: <1E-06.
    • Direct Jump Type: <1E-09.
  • Reliability (Pmc):
    • Condition (SNR/Tac):
      • Locking Type: 6 dB/11 ms, <1E-3.
      • Permitting Type: 3 dB/20 ms, <1E-4.
      • Direct Jump Type: 0 dB/40 ms, <1E-4.
  • Man-Machine Interface: Command pick-up times, hold times, duration monitoring, state of command outputs during link alarm, alarm and unblocking level thresholds.
  • Standard: IEC60834-1.
  • Protection Event Records: Stored in non-volatile memory, up to 24K records.

QL-101 3000 Equipment Structure

QL-101 3000carrier rear panel