Motor Drive Interface Circuit With MCU Link to Cut Isolator Count
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional motor driving apparatus interface circuits face increased costs and installation space requirements due to the use of digital isolators for insulation, particularly when dealing with additional device units that are not directly related to motor driving control.
Innovation Solution
Incorporating a second MCU within the power circuit unit to communicate with the first MCU of the control panel unit via a communication line, reducing the need for digital isolators by isolating only essential signals and allowing data communication between MCUs for control and monitoring of additional device units.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If digital isolators are used for insulation of all signals between power circuit unit and control panel unit, then insulation safety is improved, but manufacturing cost and installation area increase
Solution Approach 1:
The patent segments the signal transmission paths into two categories: essential signals (motor driving control signals) and non-essential signals (additional device unit signals). Digital isolators are applied only to essential signals that require insulation safety, while non-essential signals are transmitted without isolators through the communication line between first and second MCUs. This selective segmentation maintains insulation safety for critical functions while reducing overall device complexity and installation area.
2Reliability
If digital isolators are used for insulation of all signals between power circuit unit and control panel unit, then insulation safety is improved, but manufacturing cost increases
Solution Approach 1:
The patent segments the signal transmission paths into two categories: essential signals (motor driving control signals) and non-essential signals (additional device unit signals). Digital isolators are applied only to essential signals that require insulation safety, while non-essential signals are transmitted without isolators through the communication line between first and second MCUs. This selective segmentation maintains insulation safety for critical functions while reducing overall device complexity and installation area.
3Adaptability or versatility
If terminal is provided for each additional device unit, then control capability is improved, but device complexity and volume increase
Solution Approach 1:
The patent implements a universal communication line that can transmit signals for multiple additional device units (cooling fan, blower, temperature sensor, humidity sensor) without requiring separate terminals for each unit. The first MCU and second MCU communicate through this shared communication line, allowing the system to control and monitor various additional devices through a single multi-functional interface, thereby reducing device volume and complexity while maintaining full control capability.
Data Source
AI summary
The present disclosure relates to an interface circuit of a motor driving apparatus, the interface circuit comprising a power circuit unit for controlling driving of a motor, and a control panel unit which controls the power circuit unit and provides a user interface, wherein the power circuit unit further comprises a second MCU which controls a relay and an additional device unit and detects an operation state of the additional device unit, and the second MCU can communicate with a first MCU of the control panel unit via a communication line.