Motor Driving Semiconductor Device Dead Time Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The 120-degree rectangular wave driving method for motors results in significant torque ripples and noise generation, and while the sine wave driving method can reduce these issues, it compromises reliability due to the semiconductor device's susceptibility to noise-induced malfunctions and electrical shortages.
Innovation Solution
A semiconductor device with a dead time generation function is introduced, which includes a controlling semiconductor device and a motor driving semiconductor device, equipped with a dead time generator circuit and protective mechanisms to prevent electrical shortages and ensure high reliability, applicable across various control methods.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a sine wave driving method is used to reduce torque ripples and noise, then motor noise is reduced, but reliability decreases due to semiconductor device susceptibility to noise-induced malfunctions
Solution Approach 1:
The patent divides the semiconductor device into two separate devices: a controlling semiconductor device for generating control signals and a motor driving semiconductor device for driving the motor. This segmentation isolates the controlling device from the noisy motor environment, allowing the use of sine wave driving method while maintaining reliability of the control signals.
Solution Approach 2:
The patent introduces an intermediary approach where the controlling semiconductor device generates control signals that are then processed by the motor driving semiconductor device. This intermediary structure protects the controlling device from direct exposure to motor noise while still enabling sophisticated control methods like sine wave driving.
2Device complexity
If a 120-degree rectangular wave driving method is used, then circuit structure remains simple and inverter cost is reduced, but torque ripples increase and noise is generated
Solution Approach 1:
By segmenting the semiconductor device into controlling and motor driving functions, the patent enables the use of complex sine wave driving methods in the motor driving device while keeping the controlling device relatively simple. This resolves the contradiction by distributing complexity appropriately.
Solution Approach 2:
The motor driving semiconductor device independently handles the complex switching operations required for sine wave driving, while the controlling semiconductor device focuses on generating control signals. This self-service division allows each device to optimize its own complexity.
3Adaptability or versatility
If the controlling semiconductor device is placed in a noisy motor environment, then integration is improved, but the device is susceptible to noise-induced malfunctions and electrical shortages
Solution Approach 1:
The patent physically separates the controlling semiconductor device from the motor driving semiconductor device, placing the controlling device in a location with fewer noise sources while keeping the motor driving device close to the motor. This segmentation resolves the contradiction between integration and noise resistance.
Solution Approach 2:
The patent applies different quality requirements to different parts of the system: the controlling semiconductor device is designed for high reliability and noise resistance, while the motor driving semiconductor device is designed for high power handling. This local quality differentiation resolves the contradiction.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A motor driving semiconductor device (10) has: six switching elements (T1-T6) for driving a three-phase motor; three output terminals (P9-P11) for applying output voltages to three terminals of coils of the three-phase motor; drive circuits (KT, KB) for driving the six switching elements; and six control signal input terminals (P1-P6) for receiving six control signals for on/off control of the six switching elements, wherein the motor driving semiconductor device is formed by sealing at least one semiconductor chip in one package with resin, and further includes a dead time generation function of generating a dead time relative to the six control signals.