Universal Motor Braking Ignition Angle Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for electrodynamic braking of universal motors do not adapt to changes in speed caused by external influences or target speed deviations, leading to malfunctions such as undesired restarts and increased brush fire and wear on the armature.
Innovation Solution
The method adapts the ignition angle of the second semiconductor switch to the actual speed profile during braking, using a table-based assignment that allows for flexible ignition angle adjustments based on current speed, reducing wear and enabling handling of varying loads.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fixed ignition angle profile is used during braking, then the control is simple, but the braking process cannot adapt to speed changes causing malfunctions and increased wear
Solution Approach 1:
The ignition angle is dynamically adapted during braking based on the actual speed profile rather than using a fixed predetermined profile. The control device continuously adjusts the ignition angle of the second semiconductor switch according to measured speed deviations, transforming the static control system into a dynamic one that responds to real-time conditions.
Solution Approach 2:
A feedback mechanism is implemented where the actual speed is continuously measured during braking and compared with the target speed profile. Based on this feedback, the control device adjusts the ignition angle to correct deviations, ensuring the motor follows the desired braking trajectory and preventing malfunctions.
2Reliability
If the ignition angle is not adapted to actual speed, then the control is simpler, but brush fire and armature wear increase
Solution Approach 1:
The control system measures actual speed during braking and uses this feedback to adjust the ignition angle dynamically. This ensures the ignition timing remains optimal under varying conditions, preventing brush fire and reducing armature wear by avoiding improper commutation.
Solution Approach 2:
The ignition angle parameter is continuously adjusted based on actual speed measurements. By changing this critical parameter in response to speed deviations, the system maintains optimal commutation conditions throughout the braking process, protecting the armature from damage.
3Productivity
If a predefined ignition angle assignment is used, then implementation is easier, but braking time cannot be optimized for varying loads
Solution Approach 1:
The system transitions from static predefined ignition angle assignments to dynamic real-time adjustment. The control device continuously adapts the ignition angle based on actual speed and load conditions, optimizing braking performance for varying loads while maintaining ease of implementation through automated control.
Solution Approach 2:
The ignition angle parameter is dynamically changed according to actual operating conditions rather than following a fixed assignment. This allows the braking process to be optimized for different load scenarios, improving braking speed and efficiency while the control device handles the complexity of adaptation.
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 approach significantly shortens braking time, reduces armature current, and minimizes wear on the commutator, enhancing the safety and efficiency of the braking process by accounting for individual operating conditions and maximum loads.
Implementation Method 1
electrodynamic braking of a universal motor... ignition angle of a second electronic semiconductor switch is adapted to an actual speed
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to an improved electrodynamic method for the braking of a universal motor. By means of assigning ignition angles of an electronic semi-conductor switch that short-circuits the armature of the universal motor during the braking operation to rotational speeds, the ignition angle of the semi-conductor switch is adapted to the actual rotational speed by means of determining the rotational speed. As a result, a significant shortening of the braking time and a significant reduction of brush sparking at the armature advantageously occurs, which can advantageously lead to reduced wear and hence a prolonged service life of the universal motor.