Motor Control Device Delaying Energization Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Brushless motors experience efficiency losses and increased power consumption at low rotation speeds due to rapid switching of energization patterns, which is not optimized for varying rotation speeds, leading to suboptimal performance in fan motors.
Innovation Solution
A motor control device with an energization pattern output portion and an inverter circuit that delays the output timing of energization patterns based on the motor's rotation speed, selectively connecting stator coils to the power supply, thereby optimizing efficiency across different speed ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the energization pattern switching timing is determined according to Hall element signals, then the rotor position detection timing becomes quick, but the efficiency lowers and power consumption increases at low rotation speeds
Solution Approach 1:
The patent applies dynamics by making the energization pattern switching timing variable according to rotation speed. At high speeds, switching follows Hall element signal changes for quick response. At low speeds, the switching timing is delayed to prevent premature energization changes, optimizing efficiency across different operating conditions
Solution Approach 2:
The patent changes the timing parameter of energization pattern switching based on rotation speed. By adjusting when the energization pattern switches relative to rotor position, the system optimizes power consumption - delaying switching at low speeds to match the slower mechanical response and prevent energy waste
2Measurement precision
If the Hall elements are shifted in arrangement to compensate for detection timing deviation, then low-speed detection accuracy improves, but efficiency cannot be always optimized according to rotation speed
Solution Approach 1:
Rather than using a fixed Hall element arrangement, the patent dynamically adjusts the energization pattern switching timing based on detected rotation speed. This allows the system to adapt to varying speeds without requiring multiple Hall element configurations, maintaining both detection accuracy and efficiency across all operating ranges
Solution Approach 2:
The patent changes the timing parameter of energization switching based on rotation speed feedback. This parameter adjustment compensates for detection timing issues at different speeds without requiring physical reconfiguration of Hall elements, thereby maintaining both measurement precision and energy efficiency
3Speed
If the energization pattern switches rapidly at low rotation speeds, then the rotor position detection timing becomes quicker, but the rotor cannot use effectively the magnetic force generated by stator coils
Solution Approach 1:
The patent makes the energization pattern switching dynamic by delaying it at low rotation speeds. This prevents the stator coils from changing magnetic fields too quickly for the rotor to respond to, ensuring effective magnetic force utilization while still maintaining adequate detection timing response
Solution Approach 2:
The patent applies preliminary anti-action by proactively delaying the energization pattern switching before efficiency loss occurs. By anticipating the problem of premature switching at low speeds, the system prevents ineffective magnetic force utilization rather than attempting to correct it afterward
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
The solution effectively reduces current consumption and enhances efficiency by delaying energization pattern switching at low speeds, resulting in improved power utilization and reduced power consumption, particularly evident in the middle-speed range.
Implementation Method 1
The inverter circuit (130) selectively connects respective coils provided in the motor to a power supply according to the output energization pattern
Implementation Method 2
the brushless motor includes a plurality of Hall elements, and detects a rotation position of a rotor, using a signal output from the Hall elements
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A motor control device includes an energization pattern output portion and an inverter circuit. The energization pattern output portion cyclically outputs a plurality of energization patterns. The inverter circuit selectively connects respective coils provided in a motor to a rectifier circuit according to the output energization pattern. The energization pattern output portion delays the output timing of the energization pattern according to a rotation speed of the motor.