Three-Wire Communication Apparatus with Phase-Based Noise Avoidance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In communication systems where air conditioners are connected via a three-core cable, inductive noise can occur due to the power source voltage, impairing communication quality, especially when the cable length increases.
Innovation Solution
A communication apparatus that detects the phase of the alternating-current voltage and only transmits or receives electric current signals when the phase is outside a specific range where induced current exceeds a reference value, thereby avoiding periods of inductive noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of stationary object
If the cable connecting air conditioners becomes longer, then the coverage area and flexibility of the system is improved, but inductive noise increases causing communication failure
Solution Approach 1:
The communication apparatus periodically transmits synchronization signals at predetermined intervals to maintain communication stability. The controller activates the communication interface at specific time periods to exchange data packets, ensuring reliable communication even over long cable distances where inductive noise is present.
Solution Approach 2:
The communication apparatus implements feedback mechanisms where the controller monitors communication status and adjusts transmission timing based on received signals. The synchronization signal transmission and data packet exchange create a feedback loop that maintains communication quality by adapting to the actual communication conditions over the cable.
2Duration of action of stationary object
If communication is performed during periods of high induced current, then communication continuity is maintained, but signal interference from inductive noise increases
Solution Approach 1:
The communication apparatus transmits synchronization signals before actual data communication to establish a reference timing. This preliminary action allows the system to synchronize communication timing and avoid periods of high inductive noise, ensuring that data transmission occurs during more favorable electromagnetic conditions.
Solution Approach 2:
The controller dynamically adjusts communication timing based on the detected phase of alternating current voltage. The communication interface is activated only during time periods when inductive noise levels are acceptable, creating a dynamic communication schedule that adapts to changing electromagnetic conditions rather than operating continuously.
3Productivity
If the communication apparatus transmits signals continuously, then data transmission efficiency is improved, but communication errors due to inductive noise increase
Solution Approach 1:
The system uses periodic synchronization signal transmission at predetermined intervals to maintain communication efficiency. By structuring communication as periodic exchanges of data packets rather than continuous transmission, the system achieves efficient data transfer while avoiding periods of high inductive noise that would cause errors.
Solution Approach 2:
The feedback mechanism monitors communication success and adjusts transmission timing accordingly. When communication errors are detected due to inductive noise, the controller modifies the timing of subsequent transmissions to avoid similar interference patterns, thereby maintaining high communication accuracy while preserving overall transmission efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This configuration improves communication quality by preventing signal interference from inductive noise, ensuring reliable communication even with longer cables.
Implementation Method 1
detection means for detecting a phase of an alternating-current voltage applied between a first terminal for connecting to the power source line and a second terminal for connecting to the shared line
Implementation Method 2
a current may be induced in the communication line due to the power source voltage depending on the line capacity and cause inductive noise
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A communication apparatus (200) is connected to another communication apparatus (300) via a power source line (111), a signal line (113), and a shared line (112). The communication apparatus (200) includes a detector (220) and a communicator (230). The detector (220) detects the phase of an alternating-current voltage applied between a first terminal (201) for connecting to the power source line (111) and a second terminal (202) for connecting to the shared line (112). The communicator (230) communicates with the other communication apparatus (300) by executing at least one of transmission or reception of an electric current signal generated by opening and closing a circuit including the signal line (113) and the shared line (112) except when the phase detected by the detector (220) is within a specific range. The specific range is defined as a range in which an induced electric current flowing through the signal line (113) due to the alternating-current voltage is greater than a reference value.