Low-voltage substation area “zero wiring” communication solution, achieving anti-harmonic interference through multiple spread spectrum techniques, with communication success rate improved to over 99.5%, suitable for medium and low voltage lines in various scenarios of power IoT applications.
Current communication technology applicable to 50Hz/60Hz low-voltage power lines:
- Disperse signal energy through multiple spread spectrum to weaken harmonic interference and reduce frame missed detection/false detection probability;
- Optimize transmitter MOS control + receiver interpolation module to solve the periodic differential gain problem under 60Hz power frequency;
- In practical applications, communication success rate is improved to over 99.5%, adapting to complex power consumption environments
Technology Areas
Power Line Communication Technology, Power IoT Communication Technology
R&D Approach
(Core algorithms and hardware design are self-developed, with 2 invention patents applied for)
Pain Points and Challenges
Low-voltage power line communication technology uses distribution lines as transmission media to achieve data communication between low-voltage substation areas through modulation and demodulation technology. This technology offers the advantages of no additional wiring and low cost. However, since power lines are not dedicated communication channels, the start and stop of electrical equipment within the substation area can cause significant interference to communication, affecting the detection of communication frames by signal receiving equipment and reducing communication success rate. Low-voltage power line carrier communication technology is a communication technology that achieves data transmission and reception by superimposing high-frequency signals onto existing low-voltage power lines. Its advantage lies in the fact that it does not require additional dedicated communication lines and can be applied by relying on the widely covered low-voltage power network. This can significantly reduce the construction cost of the communication system and greatly improve the deployment efficiency of communication coverage. However, in practical applications, on one hand, due to the impedance characteristics of power lines varying with signal frequency, high-frequency signals experience significant attenuation during transmission, affecting transmission distance and quality. On the other hand, various electrical equipment and loads connected to the power lines generate complex noise, which interferes with the superimposed high-frequency communication signals, further reducing transmission stability.
Technical Principles
- Transmitter process:
Data → Channel coding → Payload modulation → Form transmission sequence → Current modulation → Signal injection into power line; - Receiver process:
Coupler signal coupling → Sampling → Interpolation + matched filtering → Frame synchronization (based on voltage zero-crossing position) → Demodulation and decoding → Recover original data; - Key steps: Interpolation module solves power frequency synchronization, multiple spread spectrum achieves anti-interference
Innovation/Features
- Anti-interference innovation:
Multiple spread spectrum disperses signal energy + multiple correlation operations concentrate energy, spreading harmonic interference across the entire frequency band;
High-pass + differential + peak clipping filter combination improves SNR by 5dB, reducing frame false detection probability to below 0.1%; - Power Frequency Adaptation Innovation:
Transmitter optimizes MOS tube control for precise signal output;
Receiver adds interpolation algorithm to solve periodic differential gain issue at 60Hz power frequency, communication success rate increased to 99.5%+
Key Performance Data
- Anti-interference Performance: Under same transmission energy, anti-interference capability improved by over 3dB;
- Recognition Accuracy: Frame recognition accuracy increased to 99.99%;
- Transmission Distance: Optimized transmission distance increased from 500m to 800m (low-voltage substation area scenario);
Scenario-Based Applications
Medium and low voltage distribution network topology identification, rapid fault location and repair for medium and low voltage, precise line loss management for medium and low voltage, distributed new energy (photovoltaic/energy storage) access topology adaptation, old residential area/urban village grid renovation, smart city distribution network and multi-scenario linkage.