Rotor Boost Circuit for Faster Pulsed EESM Turn-On

Solution Overview

Problem

Pulsed controlled electric machines face inefficiencies due to the significant time and energy required to transition from the off state to the on state, especially when operating below peak efficiency loads, leading to lower overall operational efficiency.

Innovation Solution

A boost circuit and method that harvests field energy stored in the rotor inductor during the off state, stores it, 'tops up' the energy to account for losses, and supplies it as a boost voltage to aid the rotor in quickly transitioning to the on state, reducing the start-up inductance and thereby accelerating the transition time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If pulsed control is used to operate the electric machine below peak efficiency load, then overall operational efficiency is improved, but transition time from off state to on state increases energy consumption

Engineering Contradiction:

Improveenergy consumption during transitionVSAvoidtransition time from off state to on state

Core Design Contradiction:

Loss of energyVSLoss of time

Solution Approach 1:

The boost circuit pre-charges a capacitor during the off-state period before the pulse transitions the machine on. This preliminary energy storage allows the capacitor to provide a voltage boost during the transition phase, reducing both the time required and energy consumed for the off-to-on state transition.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system recovers and stores the rotor's own field energy in the capacitor during the off-state, then uses this self-recovered energy to boost the transition back to the on-state. This self-service approach eliminates the need for external energy sources during transitions, reducing overall energy consumption.

Inventive Principle:

Principle #25Self-service

2Productivity

If the rotor is transitioned quickly from off state to on state, then productivity is improved, but energy consumption during transition increases

Engineering Contradiction:

Improvetransition speedVSAvoidenergy consumption during transition

Core Design Contradiction:

ProductivityVSUse of energy by moving object

Solution Approach 1:

The boost circuit pre-charges a capacitor during the off-state period before the pulse transitions the machine on. This preliminary energy storage allows the capacitor to provide a voltage boost during the transition phase, reducing both the time required and energy consumed for the off-to-on state transition.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system recovers and stores the rotor's own field energy in the capacitor during the off-state, then uses this self-recovered energy to boost the transition back to the on-state. This self-service approach eliminates the need for external energy sources during transitions, reducing overall energy consumption.

Inventive Principle:

Principle #25Self-service

3Loss of energy

If field energy is harvested and stored in a capacitor, then energy efficiency is improved, but device complexity increases

Engineering Contradiction:

Improvefield energy lossVSAvoidcircuit complexity

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The boost circuit performs multiple functions: it harvests field energy from the rotor, stores it in the capacitor, and provides voltage boosting during transitions. By combining these functions into a single circuit, the patent minimizes additional complexity while maximizing energy recovery benefits.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system recovers and stores the rotor's own field energy in the capacitor during the off-state, then uses this self-recovered energy to boost the transition back to the on-state. This self-service approach eliminates the need for external energy sources during transitions, reducing overall energy consumption.

Inventive Principle:

Principle #25Self-service

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 reduces the transition time from the off state to the on state, enhancing the overall efficiency of pulsed controlled electric machines by minimizing time spent in lower efficiency states and reducing energy consumption.

Implementation Method 1

harvesting the field energy stored in an inductor of a rotor when the EESM is transitioning to the off state

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

storing the harvested field energy on a storage device

Methodology Applied

Scientific EffectCapacitance: Capacitance

Data Source

PatentUS20240088806A1Boosted rotor supply circuit and method for improving pulsed electric machine efficiency

Publication Date: 2024.03.14 TULA ETECHNOLOGY INC

AI summary

A pulsed control of an Externally Excited Synchronous Machines (EESM), including a boost circuit and method for (1) harvesting the field energy stored in rotor winding when the EESM is transitioning to the off state following an on pulses, (2) storing the harvested field energy on a storage device, (3) optionally “topping” up the harvested field energy stored on the storage device, and (4) supplying the harvested and stored field energy as a “boost voltage” to the rotor, just as the EESM is transitioning on for the next pulse, the boost voltage aiding the rotor in quickly overcoming it's start-up inductance, rapidly turning on the rotor, resulting in a much faster transition time from the off state to the on state at the start of the next pulse.