DE102017210706A1 - Electrical assembly and method for controlling an electrical assembly - Google Patents

Abstract

The invention relates to an electrical assembly (1) with a sensor (10) and a method for controlling an electrical assembly (1). In this case, measurement data provided by the sensor system (10) which characterize a thermo-mechanical property of the module (1) are received and processed into a control signal for at least one active influencing element (17) of the module (1). By means of the at least one active influencing element (17), the thermomechanical property is influenced by active influencing of at least one component (2, 3, 4, 5, 6, 7, 9) of the assembly (1) as a function of the control signal and thereby an expansion difference between minimizes at least two components (2, 3, 4, 5, 6, 7, 9) of the assembly (1).

Description

The invention relates to an electrical assembly with a sensor and a method for controlling an electrical assembly.

Current innovative design concepts for electrical and electronic assemblies are characterized by an increasing degree of integration and miniaturization. Particularly problematic thereby are a controlled, targeted cooling and handling damaging expansion differences by different thermal expansion coefficients of various components or components.

As well as temperature gradients within the assemblies, these different expansion coefficients can lead to thermomechanical stresses which, depending on the design of joint connections between different components or functional materials, can cause cumulative damage to respective interfaces, joining materials and functional elements. A prominent example of this from the construction and connection technology of electronics is the known solder fatigue due to cyclic exchange loads.

Known approaches to counteract these problems typically aim for a passive matching of the respective loads and the respective load capacity of the affected building and structural elements. It is therefore attempted to combine respective joining partners and materials in such a way that expansion differences, that is to say faulty expansions, are optimally avoided in terms of design. In addition, the most fatigue-resistant brazing materials and / or large joint gaps are used, which promote stress reduction. Today, however, these measures are reaching their limits due to the increasing need for miniaturization, increasing demands on electrical and thermal performance, and associated temperature gradients arising during operation. In order to achieve the often required today electrical and thermal performance, for example, attempts to combine ceramic materials and glass fiber composites in a confined space, although these materials have a very different expansion behavior under thermal stress, ie a large expansion mismatch. Thus, new solutions are required, since the problems and challenges that occur can no longer be handled with satisfactory quality and cost efficiency by means of the known conventional measures.

For example, use and improvement of the previously used passive material-geometric optimizations clearly counteract the development goals of miniaturization, cost efficiency and increased functionality. For example, the use of highly stress-resistant solder materials, as well as a transition to higher-value joining processes - for example soldering instead of sintering - significantly increases the cost of a particular product.

Object of the present invention is to provide an electrical assembly with improved thermo-mechanical behavior.

This object is achieved by one of the subjects of the independent claims. Advantageous embodiments and further developments of the invention are specified in the dependent claims as well as in the description and in the drawing.

An electrical subassembly according to the invention has a sensor system and at least one controllable active influencing element as well as a control device connected thereto. The control unit processes measurement data provided by the sensor system, which characterize a thermal and / or mechanical property of the module, to a control signal for the at least one active influencing element. The at least one active influencing element influences the thermal and / or mechanical property of the assembly as a function of the control signal by actively influencing at least one component of the assembly and thereby minimizes an expansion difference, ie a faulty expansion, between at least two components of the assembly. In other words, the electrical module thus influences its thermal and / or mechanical properties itself by means of a control or regulating circuit.

For the purposes of the present invention, the electrical or electronic assembly can be understood as a constructive and / or functional composite or as a structural and / or functional unit made of integrated and / or discrete, active and / or passive components or components. These components or components may be electrically connected to each other by an electrical line network. The at least one component that is actively influenced does not necessarily have to fulfill an electrical or electronic signal or data processing or forwarding function. The at least one component can therefore be an electrically insulating support or structural element or a cooling element of the module.

The active influence of the component can mean, for example, that a thermal, mechanical and / or electrical property of the device or a corresponding parameter value influenced, that is modified. Likewise, the active influence, for example, include or mean a position, position, shape and / or size change of the component. For this purpose, the active influencing element can be designed, for example, as a microsystem (MEMS, microelectromechanical system). The active influencing element can be arranged on or at the at least one component, embedded in or integrated therein or connected or coupled thereto, for example via an electrical line or a mechanical and / or thermal connection element. In order to bring about the active influencing, the active influencing element can for example be connected to a power supply of the electrical assembly and be supplied with energy via this. The same can also apply to the control unit.

The control unit may be, for example, a microchip, a microcontroller or the like or have such. The control unit can be arranged as a component of the electrical assembly in or on this. However, it is also possible to arrange the control unit spatially spaced from the other interconnected components of the assembly. While an arrangement of the control device together with the other components of the electrical assembly in a conventional composite may be advantageous in terms of miniaturization, independence and simplified contactability, a spatially separated arrangement of the controller, for example, be advantageous if this multiple electrical components or respectively at least one controls active influencing element of different electrical components, that is supplied with control signals. For this purpose, the control unit and the other components of the electrical module or the electrical components can be arranged for example on a larger board and / or integrated into a larger electrical or electronic system.

An expansion difference, ie an expansion difference between at least two components or sub-areas of the assembly means in the context of the present invention, a different thermal expansion, so for example a different length, size and / or shape change, the at least two components or sub-areas, which by different Temperatures and / or different thermal expansion coefficients of the at least two components or subregions is caused or caused. Such differences in expansion can lead to damage of the components involved, a joining material or a connection between these and / or other components or subregions of the electrical assembly. In concrete terms, this can for example result in mechanical stresses within the electrical assembly, which can lead to breakage or tearing of components and / or connections or joining materials. For the purposes of the present invention, such differences in expansion are therefore also referred to as faulty expansions.

Damage caused by incorrect expansion may occur, in particular, in the case of cyclically loaded components, connections or assemblies that are exposed to thermal, mechanical and / or electrical changeover switches. The present invention can therefore be used particularly advantageously in such fields of application in order to avoid damage, to prevent premature aging of the components, connections and / or assemblies and thus for a prolonged service life and / or increased thermal, mechanical and / or electrical load capacity to care. Through the use of the at least one active influencing element and its control for avoiding or minimizing expansion differences, the present invention advantageously reduces stress on sensitive components and thus enables the use of less expensive components and / or materials. In addition, additional design freedom, optimization scope and flexibility for a design, a structure and / or a geometry of the electrical assembly can be created or exploited. Overall, the present invention can thus advantageously allow further miniaturization, a more cost-effective production and / or an increase in power density.

While in a design or a structure of conventional electrical components usually an external influence, so for example an ambient temperature at a respective site of the electrical assembly is taken into account as a significant factor, it is a core idea of the present invention, occurring within the electrical assembly internal conditions, Circumstances and interactions. The present invention is therefore based on the finding that in the course of the progressive miniaturization and increase in the performance of electrical components in an operation of the assembly within these caused by the components themselves conditions, especially temperatures and temperature gradients are essential for a functionality and capacity of the assembly. Since conventional methods, such as an arrangement of a power semiconductor element in The greatest possible spatial distance to a temperature-sensitive component, such as a surface-mounted device (SMD, English "Surface-mounted device"), due to the increasing miniaturization and increased packing or functional density can not ensure sufficient protection of the sensitive components more, is the present The use according to the invention of the at least one active influencing element and the control thereof using the sensors of the electrical assembly are particularly effective and advantageous.

It can be specified for one, several or all of the directly or indirectly by means of the active influencing element of influenceable thermal and / or mechanical properties of the component and / or the assembly, a respective target value and / or a respective threshold. If such a threshold is exceeded - for example, by heating a component over a predetermined threshold temperature addition - so this can be detected by the sensor. Achieving or exceeding such a threshold value can serve as a signal or trigger for the control unit, which then controls the at least one active influencing element in order to bring a respective current value or measured value of a corresponding measured variable below the exceeded threshold value. For example, the active influencing element can preferably be correspondingly activated until the predetermined target value for the respectively current value of the respective measured variable has been reached. As a result, advantageously a high-frequency exceeding of the threshold value can be avoided.

For the purposes of the present invention, a change or influencing of the thermal and / or mechanical properties of a component or partial area of the electrical assembly simultaneously also means a change or influencing of the thermal and / or mechanical properties of the electrical assembly as a whole. The thermal and / or mechanical properties are collectively referred to as thermomechanical properties. Through the use of the term "thermomechanical", reference may be made to the particular thermal and / or mechanical properties, properties, components or conditions.

In an advantageous embodiment of the present invention, the at least one active influencing element has a heating element. By controlling or controlling this heating element, the at least one component can be heated, that is heated. By means of the heating element, the at least one component can thus be influenced in its temperature and thus at least indirectly in its extent. Thus, for example, the temperature of the at least one component can be adjusted to a temperature of another, in particular of an adjacent, component of the assembly by means of the heating element. Likewise, it is possible, for example, that at least one component to be heated controlled by the heating element, so bring to a certain, for example determined by the controller temperature, that thereby the actual thermal expansion, ie, for example, a change in length, the at least one component to a thermal expansion of at least one further, in particular adjacent, component of the assembly is aligned.

This can be necessary and advantageous, for example, to avoid incorrect expansion if the at least one component and the further component have different thermal expansion coefficients. The heating or temperature required for this purpose can be determined by the control unit, for example, by adjusting the temperatures of the at least one component and the further component with a characteristic field or a respective material properties of the components of the assembly describing or containing the database. To avoid or minimize thermal stress and aging of the at least one component or the assembly, the additional heating of the at least one component may seem counterintuitive, independently of, for example, a signal-processing function or functionality. However, the positive effect of avoiding or minimizing a mis-expansion achievable by heating outweighs, so that overall results in a positive effect, for example in the form of avoiding damage, reduced or slowed aging and / or prolonged life of the electrical assembly.

In a further advantageous embodiment of the present invention, the at least one active influencing element on an actuator, in particular a piezoelectric element and / or a bimetallic element. In this way, therefore, in particular a mechanical property of the at least one component can be influenced. For the purposes of the present invention, a change in state, that is to say a change in particular of a thermal and / or mechanical state of a component or of the assembly, is to be understood as a change, that is to say influencing a corresponding thermal and / or mechanical property. By controlling the actuator, for example, a position, position and / or shape of the at least one component can be influenced or modified, which means influencing a mechanical property of the at least one component. As a result, the at least one component can be brought into contact, for example, with direct mechanical, in particular heat-conducting, contact with another component of the assembly or such contact can be interrupted or canceled.

This advantageously allows active control or adaptation of a heat flow or cooling path within the electrical assembly. By means of the actuator can thus be set in each case a current preferred direction for a heat flow within the assembly. This in turn allows adaptation of a temperature gradient or a temperature distribution within the electrical assembly, which can be exploited to avoid or minimize the expansion difference. Likewise, by means of the actuator, the at least one component or another component mechanically coupled thereto can be brought into contact with a cooling element or such contact can be interrupted or a corresponding contact surface can be increased or reduced. It is possible, for example by means of a pulse width modulation, and / or by adjusting a size of a contact surface between two components to make not only a binary tax, but a value, for example, a heat flow rate of a particular heat flow or cooling path within the electrical assembly in several stages or infinitely adapt or adjust.

Likewise, due to temperature differences or temperature gradients and / or different thermal expansion coefficients, for example, a mechanical deformation, for example bending of at least one component within the electrical assembly, may be caused. This bending or deformation can be counteracted by means of the actuator. The actuator can thus exert a mechanical stress, a mechanical pressure or a mechanical tension on the at least one component in order to avoid or compensate for the deformation or the bending. The use of the actuator thus advantageously enables a particularly precise and flexible active influencing of the thermo-mechanical properties or of the thermomechanical behavior of the electrical assembly.

In a further advantageous embodiment of the present invention, the sensor has a plurality of, arranged on different components of the assembly sensors. These multiple sensors are configured to detect a respective thermal and / or mechanical state, ie a respective thermal and / or mechanical property of the various components. Thus, a temperature gradient or a temperature field and / or a mechanical stress field or a profile or gradient of a mechanical stress or stress within the electrical assembly can thus advantageously be detected or determined by means of the sensor system. This allows a particularly accurate evaluation of a respective current thermo-mechanical state of the electrical assembly as well as a particularly flexible and particularly precise influencing of the respective thermo-mechanical state, ie the respective thermo-mechanical property or properties of the electrical assembly.

Particularly preferably, several active influencing elements arranged on different components of the assembly can also be provided. In interaction of the plurality of sensors and the plurality of active influencing elements, an optimal influencing of the electrical assembly or of its thermomechanical properties can be achieved. An optimum may be, for example, a minimization of the one or more expansion differences within the electrical assembly, minimizing thermomechanical stress, minimizing aging or aging phenomena of the electrical assembly, maximizing a thermomechanical and / or electrical damage achievable load capacity of the electrical assembly, a Maximize the life of the electrical assembly or the like mine or be.

Another aspect of the present invention in addition to the electrical assembly according to the invention is a method for controlling an electrical assembly, in particular an electrical assembly according to the invention. In the method according to the invention, measurement data provided by a sensor system of the module are received by means of a control unit, which characterize a thermal and / or mechanical property of the module. These measurement data are processed by means of the control unit to a control signal for at least one active influencing element of the module. By means of the at least one active influencing element, the thermal and / or mechanical property of the assembly is then influenced by actively influencing at least one component of the assembly as a function of the control signal and thereby an expansion difference, ie a Missing expansion, minimized between at least two components of the assembly.

In an advantageous development of the method according to the invention, a thermal and / or mechanical behavior of the assembly is mathematically modeled and the control signal is generated as a function of the modeled behavior. Thus, a model description of components and / or functional units of the module is made or provided. To model the thermo-mechanical behavior of the assembly, for example, a predetermined model can be used, to which the measurement data acquired by means of the sensor system are supplied as input or state variables. For modeling, for example, a modeling device, which may be part of the control unit, can be used.

The modeling device can, for example, have a processor device and a memory device connected to it, just like the control device. To model the behavior, a purely mathematical model can be used. Additionally or alternatively, determined behaviors of the assembly under predetermined and / or known thermomechanical and / or electrical conditions can be used or taken into consideration, for example, by means of experimental methods, ie concrete measurements. A knowledge or prediction of a past, current and / or future behavior or state of the electrical assembly that accompanies the given model or modeling advantageously makes possible a particularly accurate, reliable, effective and efficient control of the electrical assembly, ie a correspondingly advantageous minimization of the expansion difference or the expansion differences within the electrical assembly.

For example, by means of modeling a future behavior of the assembly can be predicted or estimated. This in turn allows a preventive control of the at least one active influencing element in order to avoid, for example, anticipated thermomechanical load peaks or to cushion their effects. For example, a thermomechanical inertia that can delay an influence or an effect of the control signal, that is to say the activation of the active influencing element, can be considered or compensated.

The modeling of the thermo-mechanical behavior may also allow effective and efficient control even if, for example, not every single component of the assembly is monitored by means of an individual sensor. This is the case since by means of the model from a limited number of measured data, for example, a thermomechanical state can also be deduced from those components or subregions of the assembly that are not detected or monitored by means of the sensor. Overall, this integration or combination according to the invention makes it possible the local sensor system in or on the module, the modeling of the thermo-mechanical behavior of the module and the actively controlled influencing of the module by means of the active influencing element as a function of the modeled behavior and the measured data of the sensors, an electrical module with improved thermo-mechanical behavior, improved performance or Resilience and / or extended life to realize.

It should be explicitly noted here that the actively influenced component can be influenced independently of a possible electrical and / or signal and / or data processing functionality of this component. Thus, it is also possible for example to actively influence those components which are not actively and directly involved in electrical activity and / or signal or data processing within the electrical assembly. This clearly distinguishes the present invention from previous approaches to a mere load management, which, for example, vary or regulate a clock frequency of a computing or processing unit (CPU) in dependence on a temperature of this computing or processor device.

In a further advantageous embodiment of the method according to the invention, the model or the modeled behavior of the module takes into account a respective influence of the sensor system and of the at least one active influencing element on the thermal and / or mechanical behavior of the module. As a result, a real thermo-mechanical state and a real thermo-mechanical behavior of the electrical assembly can be modeled particularly accurately, that is, imaged and / or predicted. Particularly advantageously, this modeling, for example, in a development process or a manufacturing method for the electrical assembly, are used to determine an optimal arrangement or positioning of the sensor and / or the at least one active influencing element, for example, a performance or resilience of the electrical assembly maximize.

In a further advantageous embodiment of the method according to the invention are as the Measured data detected at least one temperature gradient within the assembly and / or a change in shape and / or dimension of at least one component of the assembly spatially and temporally resolved. For this purpose, the sensors can have a plurality of individual sensors in order to detect or determine a spatial and temporal course of the detected measured variables. This can advantageously enable a particularly accurate and effective influencing of the thermo-mechanical properties of the assembly, ie a particularly effective and efficient control of the electrical assembly.

The detection of a temperature gradient is particularly advantageous since temperature gradients form a significant influencing factor or a significant cause of expansion differences within assemblies. The detection of the change in shape and / or dimension can be particularly advantageous, for example, if the respective temperature of the component changing its forum and / or dimension can not or can not be detected precisely and / or varied within the component, for example, and / or the thermal expansion coefficient of the respective component is not known. The detection of the change in shape and / or dimension may be possible, for example, by means of a sensor arranged on respective outer sides of the component. By contrast, for an accurate temperature measurement, for example, an arrangement of a temperature sensor in a central region of the respective component may be necessary, which, for example due to a packaging and / or a high functional density, can not always be achieved. Likewise, it can be difficult to determine an effective coefficient of thermal expansion of the component at temperatures varying within the respective component and / or when constructing the component from a plurality of different materials. These difficulties can be avoided by detecting the changes in shape and / or dimension.

für die beiden Bauelemente eingestellt oder sichergestellt, wobei α₁ den thermischen Ausdehnungskoeffizienten des ersten Bauelements, α₂ den thermischen Ausdehnungskoeffizienten des zweiten Bauelements, ΔΘ₁ die Temperaturänderung des ersten Bauelements und ΔΘ₂ die Temperaturänderung des zweiten Bauelements angibt. Die relativen Längenänderungen der beiden Bauelemente sollen also gleich sein. Die durch die jeweilige Temperaturänderung verursachte thermische Ausdehnung kann bei einer Erwärmung positiv und bei einer Abkühlung negativ sein. Eine negative thermische Ausdehnung bedeutet dabei beispielsweise ein Zusammenziehen oder eine kontraktive Längenänderung. Durch das separate Erfassen der jeweiligen Temperaturänderungen der beiden Bauelemente kann eine besonders genaue Anpassung, also Angleichung der thermischen Ausdehnungen der beiden Bauelemente erreicht werden. Durch das Anpassen oder Angleichen der thermischen Ausdehnungen wird also der Ausdehnungsunterschied zwischen den beiden Bauelementen minimiert, insbesondere idealerweise zu null.In a further advantageous embodiment of the method according to the invention, a respective temperature change of the at least one component and a second component of the assembly is detected by means of the sensor system. By actively influencing at least one of these two components, their thermal expansions are adapted to each other. In other words, for example, when a temperature change of two components by the active influence of the condition $${\mathrm{\alpha }}_1\cdot \mathrm{\Delta }{\mathrm{\Theta }}_1={\mathrm{\alpha }}_2\cdot \mathrm{\Delta }{\mathrm{\Theta }}_2$$

set or ensured for the two components, wherein α ₁ the coefficient of thermal expansion of the first component, α ₂ the thermal expansion coefficient of the second component, ΔΘ _1, the temperature change of the first component and ΔΘ ₂ indicates the change in temperature of the second component. The relative changes in length of the two components should therefore be the same. The thermal expansion caused by the respective temperature change can be positive for heating and negative for cooling. A negative thermal expansion means, for example, a contraction or a contractive change in length. By separately detecting the respective temperature changes of the two components, a particularly accurate adaptation, ie approximation of the thermal expansions of the two components can be achieved. By adapting or equalizing the thermal expansions, therefore, the expansion difference between the two components is minimized, in particular ideally to zero.

In a further advantageous embodiment of the method according to the invention, a thermally conductive, mechanical contact between at least two components of the assembly is made or interrupted by means of the active influencing element in response to the control signal. The actively influenced at least one component can be one of the at least two components, between which the contact is made or interrupted. However, it is also possible that as a result of the active influencing of the at least one component, for example, a second component is indirectly influenced and brought into contact with a third component or such a contact between the second and the third component is interrupted. A mechanical contact in this sense exists when the at least two components, in particular directly, touch.

Since the expansion difference minimized by means of the present invention is particularly relevant to the operation of the electrical assembly, particularly at high temperatures, temperature changes, temperature gradients and / or power densities, the present invention may be particularly advantageous and beneficial for, for example, power electronic assemblies, electric drives, inverters and the like be used.

The properties and refinements of the electrical assembly according to the invention and the corresponding advantages given heretofore and hereinafter are mutatis mutandis applicable to the method according to the invention and / or components or devices used or usable for carrying out the method according to the invention and vice versa. Thus, such developments of the invention also belong to the invention inventive electrical assembly and the method according to the invention, which have embodiments that are not explicitly described here in the respective combination.

Further features, details and advantages of the present invention will become apparent from the following description of preferred embodiments and from the drawing.

The single figure shows a schematic and sectional side view of an electrical assembly with a sensor and several controllable active influencing elements for actively influencing a thermal and / or mechanical property of the assembly.

The exemplary embodiments explained below are preferred embodiments of the invention. In the exemplary embodiments, the described components of the embodiments each represent individual features of the invention, which are to be considered independently of one another, which each further develop the invention independently of one another and thus also individually or in a different combination than the one shown as part of the invention. Furthermore, the described embodiments can also be supplemented by further features of the invention already described.

The single FIGURE shows a schematic and sectional side view of an electrical or electronic assembly 1 in an exemplary construction. In the present case, the electrical assembly 1 a base element 2 on, which may be, for example, a cooling element or heat sink. In the vertical direction of the electrical assembly 1 on or above the base element 2 is a ceramic element 3 which may, for example, be a ceramic substrate for a directly bonded copper structure (DBC, "Direct Bonded Copper", also DCB, "Direct Copper Bonded"). The ceramic element 3 can be used as the main heating path to dissipate heat from overlying parts of the electrical assembly 1 towards the base element 2 serve. It is particularly advantageous that the ceramic element 3 can have a high thermal conductivity and at the same time as an electrical insulator, as compared to the example metallic base element 2 , can serve.

Above the ceramic element 3 is presently a power semiconductor element 4 arranged, which laterally of electrically insulating support elements 5 is enclosed. The support elements 5 can be used as bearing surfaces for one above the power semiconductor element 4 arranged main wiring carrier 6 the electrical assembly 1 serve. Due to the mechanically stable support elements 5 can be avoided that the power semiconductor element 4 for example, is damaged by mechanical pressure when joining the electrical assembly. The main wiring substrate 6 serves in particular as a carrier or substrate for an electrical line network 7 , Which present this and also further sub-areas of the electrical assembly 1 interspersed. It should be noted that not all individual parts or sub-areas of the pipeline network 7 including all contacts and the like are explicitly marked. On the main wiring board 6 are however as components of the pipeline network 7 two contacts 8th for one above the main wiring substrate 6 arranged surface-mounted device (SMD, English "Surface-mounted Device") 9 arranged and marked.

Furthermore, the electrical assembly 1 a sensor with several spatially distributed in or on different components of the electrical assembly 1 arranged sensors 10 on. The sensors 10 may be the same or different types, such as temperature sensors, pressure sensors or sensors for detecting mechanical stresses, movements, shape or extent changes. By means of the sensors 10 For example, a temperature field and / or mechanical quantities such as bends or contractions within the electrical assembly 1 be resolved locally and temporally resolved. Corresponding from the sensors 10 acquired measured values or measured data are transmitted to a control unit, not shown here. The control unit can be designed for example as a microchip or microcontroller and / or part of the power semiconductor element 4 be. To transmit the measured data, for example, parts of the pipeline network 7 the electrical assembly 1 be used. Corresponding contacts or connections of the individual sensors 10 are not explicitly shown here for the sake of clarity. Likewise, for example, a wireless transmission of the measured data to the control unit may be possible.

Against the background of increasing miniaturization and increasing functional and power density within devices such as the electrical assembly 1 , it can be observed that due to temperature differences and / or different thermal expansion coefficients of the components of the electrical assembly 1 Faulty expansion and mechanical stress can occur, leading to damage and / or premature aging of the electrical assembly 1 being able to lead.

To counter this problem, the electrical assembly in the present case has several active influencing elements 17 on, spatially distributed in or on different components of the electrical assembly 1 are arranged.

The means of the sensors 10 recorded measurement data thus characterize a thermal and / or mechanical, in short a thermomechanical property of the electrical assembly 1 or the respective component in or on which a respective one of the sensors 10 is arranged. By means of the active influencing elements 17 However, a thermomechanical property of the electrical assembly 1 or the respective component can be influenced. For this purpose, the controller depending on the of the sensors 10 provided measurement data respective control signals for the active influencing elements 17 generate and transmit to this. Again, such compounds are not shown for clarity, where also a wireless transmission of the respective control signals may be possible.

For example, in the base element 2 a first sensor 11 and a first active influencing element 18 integrated. In the ceramic element 3 are a second sensor 12 and a second active influencing element 19 integrated. In the power semiconductor element 4 integrated or arranged on this are a third sensor 13 and a third active influencing element 20 , In the main wiring board 6 integrated are a fourth sensor 14 , a fifth sensor 15 , a fourth active influencing element 21 and a fifth active influencing element 22 , At the SMD 9 are a sixth sensor 16 and a sixth active influencing element 23 arranged.

It can, for example, by means of the third sensor 13 a temperature increase of the power semiconductor element 4 and by evaluation of the second sensor 12 and the first sensor 10 detected measurement data, a temperature field or a temperature gradient are determined, for example, from the power semiconductor element 4 through the ceramic element 3 into the base element 2 can extend into it. Due to their different functions and consequent different material compositions, the power semiconductor element 4 , the ceramic element 3 and the base element 2 have significantly different thermal expansion coefficients. The temperature gradient between these components could thus lead to different thermal expansions or changes in length of these components without further measures.

In order to avoid or compensate for such erroneous expansions, for example, the second active influencing element 19 be designed as a heating element and used to the ceramic element 3 to heat up a difference in the thermal expansion coefficient of the ceramic element 3 and the power semiconductor element 4 on the one hand and / or the ceramic element 3 and the base element 2 on the other hand. By means of the second active influencing element 19 increased temperature of the ceramic element 3 So then the otherwise possible incorrect expansion can be avoided or reduced so that it does not damage the electrical assembly 1 comes.

vorgegeben sein, wobei α_n, α_m,... die thermischen Ausdehnungskoeffizienten der unterschiedlichen Bauelemente und q_n(t), q_m(t),... die jeweilige zeitabhängige Temperatur beziehungsweise Temperaturänderung angeben.In particular, the temperatures or the temperature field can be detected or determined not only locally, but also in time. Thus, an active temperature or temperature field management may be provided to achieve a minimization of effective mis-expansion by reducing local expansion differences. As the goal of the appropriate control or regulation can be achieved or fulfilled the condition $${\mathrm{\alpha }}_{\text{n}}\cdot {\text{q}}_{\text{n}}\left(\text{t}\right)={\mathrm{\alpha }}_{\text{m}}\cdot {\text{q}}_{\text{m}}\left(\text{t}\right)=...$$

be given, where α _n , α _m , ... the thermal expansion coefficients of the different components and q _n (t), q _m (t), ... indicate the respective time-dependent temperature or temperature change.

In another example, the main wiring substrate may be 6 and the SMD 9 have different thermal expansion coefficients. The SMD 9 For example, it may be sensitive to a heat influence or a temperature increase. Will then by means of the fifth sensor 15 and the sixth sensor 16 a temperature difference between the main wiring substrate 6 and the SMD 9 determined, it may be appropriate without further action from resulting possibly resulting expansion by heating the SMD 9 be compensated, as this leads to thermal damage of the SMD 9 could lead. However, compensating for the corresponding misregistration may still be desirable, for example, damage to an electrical connection of the SMD 9 to the mains 7 at the contacts 8th to avoid. In such a case, the fifth active influencing element 22 be formed for example as a mechanical actuator. By means of the fifth active influencing element 22 can then apply a mechanical force to the main wiring substrate 6 be applied, for example, resulting from a temperature difference or temperature change uneven bending of the main wiring substrate 6 in comparison to bending or changing the shape of the SMD 9 or the contacts 8th compensate. The main wiring substrate 6 can therefore by means of the fifth active influencing element 22 be actively bent in the opposite direction to a deflection caused by the temperature change or a temperature gradient to maintain a straight, neutral position and shape or bending to a corresponding change in position and / or shape of the SMD 9 and / or the contacts 8th equalize. An active mechanical influence by means of the active influencing elements 17 thus represents an alternative to the thermal influence possibility, Fehlausdehnungen in the electrical assembly 1 to avoid or compensate.

Overall, the use described allows the avoidance or minimization of erroneous expansions as to the components of the electrical assembly 1 acting stress factors by a thermomechanical influence of the electrical assembly 1 or individual components for minimizing the incorrect expansion taking into account a respective temperature or temperature change or respective temperature differences and respective differences of the respective thermal expansion coefficients dynamically compensated electrical assemblies or structures, which thus compared to conventional electrical assemblies or structures have improved thermo-mechanical behavior.

LIST OF REFERENCE NUMBERS

1

electrical assembly

2

base element

3

ceramic element

4

Power semiconductor element

5

support elements

6

Main wiring support

7

line network

8th

contacts

9

SMD / Surface Mounted Device

10

sensors

11

first sensor

12

second sensor

13

third sensor

14

fourth sensor

15

fifth sensor

16

sixth sensor

17

active influencing elements

18

first active influencing element

19

second active influencing element

20

third active influencing element

21

fourth active influencing element

22

fifth active influencing element

23

sixth active influencing element

Claims (10)

Electrical assembly (1), comprising a sensor system (10), characterized in that the assembly (1) has at least one controllable active influencing element (17) and a control device connected to it, which measurement data provided by the sensor system (10), which a thermal and / or mechanical property of the assembly (1) characterized processed to a control signal for the at least one active influencing element (17), which in response to the control signal by actively influencing at least one component (2, 3, 4, 5, 6, 7, 9) of the assembly (1) influences the thermal and / or mechanical property of the assembly (1) and thereby an expansion difference between at least two components (2, 3, 4, 5, 6, 7, 9) of the assembly (1) minimized. Electrical assembly (1) according to Claim 1 , characterized in that the at least one active influencing element (17) has a heating element. Electrical assembly (1) according to any one of the preceding claims, characterized in that the at least one active-influencing element (17) comprises an actuator, especially a piezo element and / or a bimetal element. Electrical assembly (1) according to one of the preceding claims, characterized in that the sensor system (10) has a plurality of sensors (10, 10, 10, 6, 7, 9) arranged on different components (2, 3, 4, 5, 6, 7, 9) of the assembly (1). 11, 12, 13, 14, 15, 16) which detect a respective thermal and / or mechanical state of the various components (2, 3, 4, 5, 6, 7, 9). Method for controlling an electrical assembly (1), characterized in that - measurement data provided by a sensor device (10) of the assembly (1), which characterize a thermal and / or mechanical property of the assembly (1), are received and supplied a control signal for at least one active Influencing element (17) of the assembly (1), and - by means of at least one active influencing element (17) by actively influencing at least one component (2, 3, 4, 5, 6, 7, 9) of the assembly (1) Depending on the control signal affects the thermal and / or mechanical property of the assembly (1) and thereby minimizes an expansion difference between at least two components (2, 3, 4, 5, 6, 7, 9) of the assembly (1). Method according to Claim 5 , characterized in that a thermal and / or mechanical behavior of the assembly (1) is mathematically modeled and the control signal is generated in dependence on the modeled behavior. Method according to Claim 6 , characterized in that the modeled behavior takes into account a respective influence of the sensor system (10) and of the at least one active influencing element (17) on the thermal and / or mechanical behavior of the module (1). Method according to one of Claims 5 to 7 , characterized in that at least one temperature gradient within the assembly (1) and / or a dimensional and / or dimensional change of at least one component (2, 3, 4, 5, 6, 7, 9) of the assembly spatially and temporally as the measured data be resolved. Method according to one of Claims 5 to 8th , characterized in that - by means of the sensor system (10) a respective temperature change of the at least one component (2, 3, 4, 5, 6, 7, 9) and a second component (2, 3, 4, 5, 6, 7 , 9) of the assembly (1) is detected and - by the active influence of at least one of these two components (2, 3, 4, 5, 6, 7, 9) whose thermal expansions are adapted to each other. Method according to one of Claims 5 to 9 , characterized in that by means of the active influencing element (17) in dependence on the control signal, a thermally conductive, mechanical contact between at least two components (2, 3, 4, 5, 6, 7, 9) of the assembly (1) is produced or interrupted ,

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