Transformerless Electric Heating Device for Wound Components

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electrical heating devices for components with windings, such as stators or rotors, require large installation space and consume high reactive power due to the use of transformers, making them inefficient and bulky.

Innovation Solution

An electrical heating device that converts alternating current from the supply network to direct current, using an electronic actuator to generate multiple phase currents and a control unit to calculate and set the intermediate circuit voltage for precise temperature control, eliminating the need for a transformer and allowing for a compact, energy-efficient design.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If a transformer is used in the heating device, then the device can heat the component, but the installation space and reactive power consumption increase significantly

Engineering Contradiction:
Improveheating capabilityVSAvoidinstallation space
Core Design Contradiction:
TemperatureVSArea of stationary object

Solution Approach 1:

The patent removes the transformer from the heating device architecture entirely. Instead of using a transformer to step down voltage, the invention uses a power converter with pulse-width modulation (PWM) to directly control the heating current. This extraction of the transformer eliminates the associated installation space requirements and reactive power consumption while maintaining the heating function through electronic control.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the electromagnetic transformer (a passive electromagnetic system) with an active electronic power converter system. The power converter uses semiconductor switches and control electronics to regulate power delivery, substituting the mechanical/electromagnetic transformation approach with an electronic control approach that achieves the same heating effect without the space and energy penalties.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Temperature

If a transformer is used in the heating device, then the device can heat the component, but the reactive power consumption increases

Engineering Contradiction:
Improveheating capabilityVSAvoidreactive power consumption
Core Design Contradiction:
TemperatureVSLoss of energy

Solution Approach 1:

The patent removes the transformer from the heating device architecture entirely. Instead of using a transformer to step down voltage, the invention uses a power converter with pulse-width modulation (PWM) to directly control the heating current. This extraction of the transformer eliminates the associated installation space requirements and reactive power consumption while maintaining the heating function through electronic control.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent replaces the electromagnetic transformer (a passive electromagnetic system) with an active electronic power converter system. The power converter uses semiconductor switches and control electronics to regulate power delivery, substituting the mechanical/electromagnetic transformation approach with an electronic control approach that achieves the same heating effect without the space and energy penalties.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Temperature

If a transformer and large power converter are used, then the heating function is achieved, but the device complexity and size increase

Engineering Contradiction:
Improveheating functionVSAvoiddevice structure
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent removes the transformer from the heating device architecture entirely. Instead of using a transformer to step down voltage, the invention uses a power converter with pulse-width modulation (PWM) to directly control the heating current. This extraction of the transformer eliminates the associated installation space requirements and reactive power consumption while maintaining the heating function through electronic control.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The power converter in the patent serves multiple functions: it acts as both the voltage transformation device (replacing the transformer) and the heating control device. By integrating these functions into a single electronic control system, the patent reduces overall device complexity while maintaining full heating capability and adding precise temperature control.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 enables efficient heating of components with reduced reactive power consumption and installation space, allowing for scalable and precise temperature control, and can be used for various component dimensions and designs.

Implementation Method 1

at least one converter device that can be connected to an electrical supply network and by which an alternating current from the supply network can be converted into a direct current

Methodology Applied
Scientific EffectRectification:

Implementation Method 2

at least one contact means that can be arranged on the component or is arranged therein and by which the component can be electrically heated by its ohmic resistance

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Data Source

PatentEP3817213B1Electric heating device for a component comprising at least one winding, and method for operating such a heating device
Publication Date: 2021.12.15 VAF
  • EP3817213B1 patent drawingFigure 1
  • EP3817213B1 patent drawingFigure 2

AI summary

The invention relates to an electrical heating device (2) for a component (4) comprising at least one winding, with at least one converter unit (6) that can be connected to an electrical supply network (8) and by which an alternating current of the supply network (8) can be converted into a direct current, with at least one contact means (10) that can be arranged on the component (4) and by which the component (4) can be electrically heated by its ohmic resistance, with at least one electronic actuator (12) that is arranged between the converter unit (6) and the contact means (10), which can be operated by an intermediate circuit voltage UDC generated by the converter unit (6) and by which at least one first phase current I1, a second phase current I2 and/or a third phase current I3 can be alternately generated at the contact means (10), and with at least one control unit (14).the at least one storage means (16) in which at least one material constant, an inductance Ls and a resistance Rs of the component (4) can be stored or stored, to which at least one sensor means (18) for detecting the at least three phase currents I1,2,3 at the component (4) can be functionally assigned or assigned, by which a temperature at the component (4) can be calculated from at least the three phase currents I1,2,3, the DC link voltage UDC and the material constant, the inductance Ls and the resistance Rs of the component (4), in particular according to Ohm's law, and a setpoint value of the DC link voltage UDC for setting a specific temperature at the component (4) can be calculated and set at the converter device (6). Furthermore, the invention relates to a method for operating such a heating device (2).