DE102015005675B4 - Automatic commutation comparison value determination for BLDC motors by means of sign determination of the EMF - Google Patents

Abstract

Method for determining the first default value (VU) to be determined for the regulation of the commutation time for the control of the stator coils of a BLDC motor via at least one first motor connection (U), characterized by the steps of: a. continuously or continuously scanning determining the sign of an assigned, corrected first voltage signal (UkorrU) derived from the EMF at the first motor connection (U) in a commutation interval (Φ3, Φ6) in which this first motor connection is not supplied with current by a control block (St), by a first sign unit (SgnU) assigned to the first motor connection (U) to generate an assigned first sign signal (SigU), b. integration and/or filtering of the relevant assigned first sign signal (SigU) by a subsequent fourth integrator (Int2U) to generate an assigned first integrated sign signal (S2U), c. optionally multiplying the assigned first integrated sign signal (S2U) before it is output by the fourth integrator (Int2U) by a first constant factor (FU), in particular by one or more sub-devices of the fourth integrator (Int2U), d. continuous and/or sampling-summing integration and/or filtering of an assigned, first corrected voltage signal (UkorrU) derived from the EMF at the first motor connection (U) in a commutation interval (Φ3, Φ6) in which this first motor connection is not supplied with current by the control block (St), by a subsequent first integrator (Int1U) to generate an assigned first threshold signal (S1U), e. comparison of the assigned first threshold signal (S1U) with a determined first default value (VU) by an assigned fourth additional comparator (CMP2U), f. Formation of an assigned first commutation signal (A1) depending on the comparison result of the assigned fourth additional comparator (CMP2U),g. Changing the commutation time of an assigned output of a control block (St) which is connected to the assigned first motor connection (U) depending on the assigned first commutation signal (A1),h. Addition of the assigned determined first default value (VU) to the assigned first integrated sign signal (S2U) by an assigned second summer (SU2U) for the first motor connection (U),i. Formation of an assigned first recharge value (S3U) depending on the result of the addition of the assigned determined first default value (VU) to the assigned first integrated sign signal (S2U) by an assigned second summer (SU2U) for the first motor connection (U),j. Storing the assigned first recharge value (S3U) in an assigned memory for this value, in particular an assigned first sample-and-hold circuit (SaHU), at least temporarily as a function of the assigned first commutation signal (A1),k. Generating the assigned first default value (VU) as a function of the current storage value of the assigned first recharge value (S3U) in the assigned memory for the assigned first recharge value (S3U), in particular in the assigned first sample-and-hold circuit (SaHU).

Description

Introduction

• • In einem ersten Zustand ist der obere Schalter geschlossen, wodurch der betreffende Motoranschluss mit der positiven Versorgungsspannung verbunden wird.
• • In einem zweiten Zustand ist der untere Schalter geschlossen wodurch der betreffende Motoranschluss mit der unteren Versorgungsspannung verbunden wird.
• • In einem dritten erlaubten Anschluss sind beide Schalter geöffnet, wodurch der zugeordnete Motoranschluss (U, V, W) nicht bestromt ist. Die betreffende Halbbrücke des Ansteuerblocks (St) ist passiv.
• • Das gleichzeitige Schließen beider Schalter ist als vierter, nicht zulässiger Schaltzustand verriegelt, um Querströme durch den oberen und unteren Schalter in Form eines Kurzschlusses auszuschließen.

The invention relates to a method for controlling the stator coils of a brushless motor with an excitation based on a permanent magnet located in the rotor. Such a motor typically comprises a rotor which itself contains a permanent magnet with at least two magnetic poles. The even number of magnetic poles should be distributed symmetrically around the axis of rotation of the motor, which is only approximately the case in reality. The rotor is rotatably mounted in a magnetic field generated by stator coils outside the rotor. The magnetic field generated by the stator coils also generally only has an approximate rotational symmetry around the rotor axis. This magnetic field is generated by the superposition of the fields of the several different stator coils, which are typically grouped symmetrically around the axis of rotation of the said rotor, which is also only approximately possible in reality. When suitably controlled, these stator coils generate a magnetic rotating field with a magnetic field-related axis of rotation, which in turn only approximately corresponds to the mechanical axis of rotation of the rotor. The rotor then follows this rotating magnetic field due to its permanent magnetization with its magnetic poles. When controlling the stator coils of such electric motors with rotors with a magnetic field excited by one or more permanent magnets, the BLDC motors mentioned above, block commutation can be used. At least three stator coils are required to generate a progressive magnetic field. The at least three stator coils are controlled by at least three associated half bridges, each of which contains an upper and a lower power switch, preferably a power transistor. This control of the power transistors takes place as synchronously as possible with the angular position of the rotor in relation to the position of the stator coils in order to maximize efficiency. The rotor position can be detected using sensors according to the state of the art or on the basis of the electromotive force induced in the stator coils of the motor. For this purpose, see 1 already referred to here, which shows such a system according to the state of the art. The stator coils of such a motor (M) preferably have three motor connections, here designated U, V and W. Here, U is the first motor connection, V the second motor connection and W the third motor connection. A control block (St) applies the supply voltages in predetermined commutation intervals (Φ ₁ to Φ ₆ , 2 ) to the respective motor terminals (U, V, W) or leaves the motor terminals (U, V, W) in some of the specified commutation intervals (Φ ₁ to Φ ₆ , 2 ) is not energized at all, whereby at the relevant motor terminals (U, V, W) in the relevant commutation intervals (Φ ₁ to Φ ₆ , 2 ) the electromotive force (EMF) causes a measurable voltage curve. As already described, each half-bridge has an upper switch for connecting the respective motor connection (U, V, W) to a positive supply voltage and a lower switch for connecting the respective motor connection (U, V, W) to a negative supply voltage. This allows a voltage that is not in 1 drawn control, which is typically located within the control block (St), connects the respective motor connection (U, V, W) to the upper or lower supply voltage. The upper and lower switches can now be switched independently of each other. Only three of the four possible switching states of the upper and lower switches of a single half-bridge are permitted.

• • In a first state, the upper switch is closed, which connects the corresponding motor terminal to the positive supply voltage.
• • In a second state, the lower switch is closed, which connects the corresponding motor terminal to the lower supply voltage.
• • In a third permitted connection, both switches are open, meaning that the associated motor connection (U, V, W) is not energized. The relevant half-bridge of the control block (St) is passive.
• • The simultaneous closing of both switches is locked as a fourth, non-permissible switching state in order to exclude cross currents through the upper and lower switches in the form of a short circuit.

Due to the control method, block commutation, one of the three half-bridges for controlling the relevant motor connections is always in the passive state, which corresponds to the third state described, in which the relevant motor connection is not actively energized. During this third state, the EMF curve becomes visible at the relevant motor connection (U, V, W) as a phase voltage against a reference potential, for example ground. With block commutation, this third state is always present at one of the three motor connections (U, V, W) during each of the six cyclically repeated commutation intervals (Φ ₁ to Φ ₆ , 2 ). The first state in block commutation is always at one of the three motor terminals (U, V, W) during each of the six cyclically repeated commu intervals (Φ ₁ to Φ ₆ , 2 ). The second state is also always present at one of the three motor terminals (U, V, W) during block commutation during each of the six cyclically repeated commutation intervals (Φ ₁ to Φ ₆ , 2 ). The phase voltage at the motor terminal (U,V,W) which is in a commutation interval (Φ ₁ to Φ ₆ , 2 ) is currently in the third high-impedance state on the part of the driving half-bridge, can, as is known from the state of the art, be used to determine the position of the rotor. 2 shows the corresponding voltages at the three motor terminals (U, V, W) in the six cyclically repeated commutation intervals (Φ ₁ to Φ ₆ , 2 ).

The following table shows the states (states 1-3) of the half-bridges in the different commutation intervals (Φ ₁ to Φ ₆ , 2 ) in this example from the state of the art. U V W _Φ1 1 3 2 _Φ2 1 2 3 _Φ3 3 2 1 _Φ4 2 3 1 _Φ5 2 1 3 _Φ6 3 1 2

• • in dem ersten Kommutierungsintervall (Φ₁) am zweiten Motoranschluss (V) gemessen werden und
• • in dem zweiten Kommutierungsintervall (Φ₂) am dritten Motoranschluss (W) gemessen werden und
• • in dem dritten Kommutierungsintervall (Φ₃) am ersten Motoranschluss (U) gemessen werden und
• • in dem vierten Kommutierungsintervall (Φ₄) am zweiten Motoranschluss (V) gemessen werden und
• • in dem fünften Kommutierungsintervall (Φ₅) am dritten Motoranschluss (W) gemessen werden und
• • in dem sechsten Kommutierungsintervall (Φ₆) am ersten Motoranschluss (U) gemessen werden.

Thus, in the current state of the art, the EMF can be measured by six different measurement configurations

• • measured in the first commutation interval (Φ ₁ ) at the second motor terminal (V) and
• • measured in the second commutation interval (Φ ₂ ) at the third motor terminal (W) and
• • measured in the third commutation interval (Φ ₃ ) at the first motor terminal (U) and
• • measured in the fourth commutation interval (Φ ₄ ) at the second motor terminal (V) and
• • measured in the fifth commutation interval (Φ ₅ ) at the third motor terminal (W) and
• • measured in the sixth commutation interval (Φ ₆ ) at the first motor terminal (U).

During this measurement, the so-called zero crossing of the EMF is often used, where it changes its sign in relation to a reference potential. The internal time base for carrying out the commutation is regulated in such a way that this zero crossing occurs exactly in the middle of the commutation interval at the motor connection (U, V, W) that is currently in the third state.

It should be briefly mentioned here that the voltage at the motor connection (U, V, W) is also called phase voltage.

Alternatively, in the third state, the course of the EMF itself, i.e. the course of the voltage at the motor connection (U, V, W), can be used to determine the commutation time. Since the speed of the rotor only influences the amplitude of the EMF, but this is otherwise a function of the course of the magnetic flux over the angular position, the integral of the EMF over the time from the zero crossing to the following commutation time represents a motor constant. Conversely, by specifying an upper limit for the integral, a commutation time with a fixed angular distance from the zero crossing can be determined directly, i.e. without the detour via a time base.

This measurement of the EMF is carried out by an EMF evaluation device (EMKA), which is 1 This measures in the six commutation intervals (Φ ₁ to Φ ₆ , 2 ) according to the current commutation interval (Φ ₁ to Φ ₆ , 2 ) and generates a separate commutation signal (A ₁ , A ₂ , A ₃ ) for each of the motor connections (U, V, W). The commutation signals (A ₁ , A ₂ , A ₃ ) are in 2 roughly drawn. The rotor position is also plotted as a parameter of the X-axis.

With each edge change on a commutation signal (A ₁ , A ₂ , A ₃ ), a control logic within the control block (St) changes its state. Alternatively, it is possible to 2 the commutation interval (Φ ₁ to Φ ₆ ) is derived from the commutation signals (A ₁ , A ₂ , A ₃ ) using a static logic. For example, the first phase can be defined as an AND operation of the negated first commutation signal nals (A ₁ ) with the negated second commutation signal (A ₂ ) and the third commutation signal (A ₃ ). The other phases can be determined in a similar way. However, it has been shown that it is preferable to briefly and asynchronously insert between the commutation intervals (Φ ₁ to Φ ₆ ) after each commutation interval (Φ _i with 0<i<7) an intermediate commutation interval (Φ _{i '} with 0<i<7) associated with this commutation interval (Φ i with 0<i<7) in which the switches of the half-bridges which change their circuit state are switched off in order to reliably exclude cross-currents. In this respect, it is sensible if the total number of states actually passed through by a finite automaton in the control block (St) is twelve instead of six.

3 shows an exemplary sub-device from the prior art for determining the first commutation signal (A ₁ ) for the commutation at the first motor connection (U). This is part of the EMF evaluation device (EMKA). In the following, the focus is on this first branch in the description. However, it will be easy for the person skilled in the art to transfer what has been written to the two corresponding branches for the second motor connection (V) with the associated second commutation signal (A ₂ ) and for the third motor connection (W) with the associated third commutation signal (A ₃ ), which are arranged in parallel. In a first stage, a virtual star point signal (SpS) is generated from the three voltages of the three motor connections (U, V, W) by means of a star connection comprising three voltage dividers (SpT ₁ , SpT ₂ , SpT ₃ ). This represents the mean value of the voltages at the three motor connections (U, V, W) and is therefore subtracted from the voltage at the first motor connection (U) by means of a second summer (SU _2U ). The corrected voltage signal (U _korr ) of the first motor connection (U) obtained in this way is the difference between the phase voltage U and the mean value of the three phase voltages and is integrated in a first integrator (Int _1U ). If necessary, the integrator can also be designed as a filter. The first threshold signal (S _1U ) is obtained. A comparator, more precisely a first comparator (CMP _1U ), compares this first threshold signal (S _1U ) with a first specified value (V _refU ) for the commutation and uses this to generate the first commutation signal (A ₁ ), which is used as described in the aforementioned control block (St) for the angular commutation of the first half-bridge, which supplies current to the first motor connection (U).

From the DE 100 54 594 A1 For example, a system for optimal commutation is known. In the 3 the DE 100 54 594 A1 Three branches of regulation are drawn, which essentially correspond to the 3 of this disclosure. The first default value (V _refU ), the second default value (V _refV ) and the third default value (V _refW ), which may coincide, are not shown, but are implicitly recognizable to the person skilled in the art by the term “comparator”. As described above, these must be DE 100 54 594 A1 be correctly parameterized in advance, which is why the procedure of DE 100 54 594 A1 does not solve the problem described.

From the US20080252240A1 A device is known that determines an optimized commutation time by evaluating the EMF. 5 the US20080252240A1 shows in the upper part the temporal course of a phase voltage (reference symbol Vu of the US20080252240A1 ). This phase voltage (reference symbol Vu of the US20080252240A1 ) always shows the EMF (reference symbol Vu' of the US20080252240A1 ) if the associated driver is high-impedance. In the lower part of the 3 the US20080252240A1 the current supply of the other two phases is shown in time, whereby the current supply of the phase in question always occurs when the signal (reference symbol Spwm of the US20080252240A1 ) is at the lower value. If the phase in question has a high resistance, the other two phases are energized and the EMF can be measured on the phase in question.

The EMF is at the considered phase voltage (reference symbol Vu of the US20080252240A1 ) can therefore only be measured when the other two phases are energized.

In an apparatus or method according to the US20080252240A1 The zero crossing of the EMF is now searched for in order to determine the optimal commutation time. This determination of the commutation time is done, if it is not in a high-impedance time period of the driver, by linear interpolation from a first point in time by a suitable time delay. The disclosure of the US20080252240A1 describes the determination of this time delay.

• Gemäß der US20080252240A1 wird zu beobachtbaren Zeitpunkten immer eine Messung der interessierenden Phasenspannung (Bezugszeichen Vu der US20080252240A1 ) genommen. Dadurch entsteht ein Stufenförmiges Signal (Bezugszeichen Sdiff der US20080252240A1 in 5 der US20080252240A1 ). Gleichzeitig wird die zeitliche Steigung der Phasenspannung (Bezugszeichen Vu der US20080252240A1 ) zu diesen Messzeitpunkten auf der Basis zweier vergangener Messungen erfasst und eine Sägezahnkurve (Bezugszeichen Sramp der US20080252240A1 ) mit dieser Steigung erzeugt. Hierdurch kann der Nulldurchgang durch einfache vorzeichenrichtige Addition dieser Signale (Bezugszeichen Sdiff und Sramp der US20080252240A1 ) linear in den Zeitraum hinein interpoliert werden, zu dem die EMK am interessierenden Phasenanschluss nicht messbar ist, da dieser bestromt wird.

If the zero crossing occurs in the non-energized time period at which the phase voltage (reference symbol Vu of the US20080252240A1 ) not on the EMF line (reference symbol Vu' of the US20080252240A1 in 3 the US20080252240A1 ), the zero crossing can only be estimated. This situation shows 5 the US20080252240A1 . This is done in the technique of US20080252240A1 carried out as follows:

• According to the US20080252240A1 At observable times, a measurement of the phase voltage of interest (reference symbol Vu of the US20080252240A1 ) is taken. This creates a step-shaped signal (reference symbol Sdiff of the US20080252240A1 in 5 the US20080252240A1 ). At the same time, the temporal gradient of the phase voltage (reference symbol Vu of the US20080252240A1 ) at these measurement times based on two previous measurements and a sawtooth curve (reference symbol Sramp of the US20080252240A1 ) with this slope. This allows the zero crossing to be determined by simply adding these signals with the correct sign (reference symbols Sdiff and Sramp of the US20080252240A1 ) can be linearly interpolated into the period during which the EMF at the phase connection of interest cannot be measured because it is energized.

1. 1. Das Verfahren der US20080252240A1 ist störanfällig, weil Störungen auf der EMK, also der interessierenden Phasenspannung (Bezugszeichen Vu der US20080252240A1 ) zu Ungenauigkeiten in der Berechnung des Nulldurchgangs führen. Damit ist das Verfahren der US20080252240A1 insbesondere bei niedrigen Drehzahlen mit geringer EMK besonders anfällig gegen Störungen, wie beispielsweise EMV.
2. 2. Der eigentliche Kommutierungszeitpunkt muss durch Addition einer linear interpolierten Zeitspanne ermittelt werden. Die Linearität beruht auf der Bildung der ersten zeitlichen Ableitung in Form des Sägezahnsignals (Bezugszeichen Sramp der US20080252240A1 ). Diese lineare Interpolation setzt einen nicht beschleunigten Motor voraus. Somit funktioniert das Verfahren der US20080252240A1 nur bei geringen Beschleunigungen. Eine solche Regelung, wie die der US20080252240A1 , ist daher nicht geeignet, hohe Lastdynamiken abzufangen.

This is a method that directly evaluates the zero crossing of the EMF and determines the zero crossing by temporal linear interpolation. This has the following disadvantages.

1. 1. The procedure of US20080252240A1 is susceptible to interference because interference on the EMF, i.e. the phase voltage of interest (reference symbol Vu of the US20080252240A1 ) can lead to inaccuracies in the calculation of the zero crossing. This makes the method of US20080252240A1 Particularly susceptible to interference, such as EMC, especially at low speeds with low EMF.
2. 2. The actual commutation time must be determined by adding a linearly interpolated time period. The linearity is based on the formation of the first time derivative in the form of the sawtooth signal (reference symbol Sramp of the US20080252240A1 ). This linear interpolation requires a non-accelerated motor. Thus, the method of US20080252240A1 only at low accelerations. Such a regulation, such as that of the US20080252240A1 , is therefore not suitable for absorbing high load dynamics.

4 shows the voltage at the first motor connection (U) at an optimal commutation for a low, a medium and a high angular speed. The first threshold signal (S _1U ) assigned to the first motor connection (U), which is calculated according to the previous description and the 3 generated increases essentially quadratically until it is equal to the first preset value (V _refU ) for commutation. The first commutation signal (A ₁ ) (not shown) then switches and the half-bridge assigned to the first motor connection (U) is commutated. It is completely irrelevant whether the angular velocity is high or low.

5 shows the voltage at the first motor connection (U) in the case of too early commutation, too late commutation and optimal commutation. The first threshold signal (S _1U ) assigned to the first motor connection (U) increases again essentially quadratically until it is equal to the first preset value (V _refU ) for the commutation. The first commutation signal (A ₁ ) (not shown) then switches and the half-bridge assigned to the first motor connection (U) is commutated. This happens in the left part of the figure. 5 too early, too late in the middle part of the figure and at an optimal point in time in the right part of the figure. It should be clear that a position of the zero crossing in the middle of the respective commutation interval is optimal.

In addition to the branch described so far within the EMF evaluation (EMKA) for the first motor connection (U), there is typically a second branch for the second motor connection (V) with associated individual elements (SU _2V , INT _1V ,CMP _1V ) and signals (V _korr , S _1V , V _refV ) and a third branch for the third motor connection (W) with associated individual elements (SU _2W , INT _1W ,CMP _1W ) and signals (W _korr , S _1W , V _refW ).

In order to achieve commutation at the same angular position of the rotor in different motors, the respective default values (V _refU , V _refV , V _refW ) must be adjusted in each case. However, since the course of the magnetic flux in relation to the angular position of the rotor is usually not known and cannot be determined from the motor data sheet, the respective default values (V _refU , V _refV , V _refW ) must first be determined experimentally. The respective default values (V _refU , V _refV , V _refW ) must be varied during operation until commutation is carried out at the desired time. Typically, however, the default values are the same (V _refU =V _refV =V _refW =V _ref ).

It is clear to the expert that the device previously described in space multiplex can also be used in time multiplex, so that only one branch in the EMF evaluation (EMKA) can be realized must be used if the values of a motor connection (U, V, W) in the commutation intervals (Φ ₁ to Φ ₆ , 2 ), in which the associated half-bridge is in states one or two, can be temporarily stored and the values can be loaded into the corresponding branch associated with the motor terminal (U, V, W) which is in the commutation intervals (Φ ₁ to Φ ₆ , 2 ) has an associated half-bridge which is in the respective commutation interval (Φ ₁ to Φ ₆ , 2 ) is currently in the third state. It is therefore sensible if parts of the device are implemented in their function by means of a microcontroller or signal processor or other computer. In this respect, the various elements described above can also be combined into one or a few elements.

Object of the invention

The object of the invention is to enable automatic determination of the respective default values for the respective motor connections (U, V, W) and thus to make it possible to eliminate the need for characterization of the individual specific BLDC motors during production. The defects identified in the state of the art are to be avoided here. This particularly concerns avoiding manual parameterization as in a method according to the DE 10 054 594 A1 and the speed dependence, as in a method of US20080252240A1 .

This object is achieved by a method according to claim 1 and a device according to claim 6.

Description of the invention

The fully automatic determination of the default value V _ref according to the invention is carried out in contrast to the method of US20080252240A1 by integrating the EMF. From the state of the art, the expert knows that this is a flow-based method that is independent of the speed and thus also independent of the acceleration, which is a decisive advantage over the method of US20080252240A1 This determination of the set value V _ref can be carried out during active operation and when the rotor is set in rotation by an external force. In contrast to the constant speed, a constant US20080252240A1 therefore not necessary. Typically, a common default value (V _ref ) is determined for all three motor connections (U, V, W). However, the determination of motor connection-specific default values (V _refU , V _RefV , V _refW ) is expressly possible for the purpose of an even more precise correction of the motor asymmetries.

The device according to the invention therefore comprises means for automatically adapting the specified value of the integration to the respective motor, which distinguishes the invention from the prior art. The aim here is that the zero crossing of the EMF is ultimately in the middle of the commutation interval (Φ ₁ to Φ ₆ ) without manual adjustment through automatic adaptation of the specified value of the integration. It is irrelevant whether the commutation is actually carried out, such as when the motor is actively running, or not, such as when the rotor is rotating externally. If the zero crossing is in the middle of the commutation interval (Φ ₁ to Φ ₆ ), the EMF at the non-energized motor connection (U, V, W) has a negative sign during the first half of the commutation interval (Φ ₁ to Φ ₆ ) and a positive sign during the second half of the commutation interval (Φ ₁ to Φ ₆ ). If, for example, you add up these signs using a fixed clock, i.e. integrate them discretely, the value of the sum at the ideal commutation time is zero. Otherwise, a deviation with a negative or positive sign occurs. A negative sign means a zero crossing that is too early, which corresponds to late commutation, and a positive sign means a zero crossing that is too late, which corresponds to early commutation. Analogous integration is of course also possible.

By adding the residual value to the comparison value of the integration, a new value is created, which is then used as a comparison value. This causes the zero crossing to move towards the middle of the commutation interval (Φ ₁ to Φ ₆ ). Small fluctuations and measurement errors can be avoided by using a hysteresis function or another filter.

Description of the characters

• 1 shows a schematic circuit of a control device from the prior art and was already described in the introduction as belonging to the prior art.
• 2 shows the three exemplary commutation signals (A ₁ , A ₂ , A ₃ ) and the associated voltage curves at the motor terminals (U, V, W) in a schematic manner for several commutation intervals (Φ ₁ to Φ ₆ ) and was already described in the introduction as belonging to the state of the art.
• 3 shows an exemplary branch within the EMF evaluation (EMKA) for the first motor connection (U) for generating the first commutation signal (A ₁ ) assigned to the first motor connection (U) and was already described in the introduction as belonging to the state of the art.
• 4 shows the quadratic increase of the first threshold signal (S _1U ) and the voltage at the first motor terminal (U) when the corresponding half-bridge of the control block (St) is in the high-impedance third state, for different angular velocities and was already described in the introduction as belonging to the state of the art.
• 5 shows the voltage at the first motor connection (U) when the associated half-bridge of the control block (St) is in the high-impedance third state, for different values of the first preset value (V _u ) according to the invention as well as the voltage curve of the first threshold signal (S _1U ) and was already described in the introduction as belonging to the state of the art.
• 6 shows an exemplary branch according to the invention within the EMF evaluation (EMKA) for the first motor connection (U) for generating the first commutation signal (A ₁ ) assigned to the first motor connection (U).
• 7 shows firstly the voltage at the first motor connection (U) when the associated half-bridge of the control block (St) is in the high-impedance third state, for different values of the first preset value (V _u ) according to the invention and secondly the voltage curve of the first threshold signal (S _1U ) and thirdly the voltage curve of the first integrated sign signal (S _2U ) for these cases.
• 8th shows an exemplary branch according to the invention within the EMF evaluation (EMKA) for the second motor connection (V) for generating the first commutation signal (A ₂ ) assigned to the second motor connection (V).
• 9 shows an exemplary branch according to the invention within the EMF evaluation (EMKA) for the third motor connection (W) for generating the first commutation signal (A ₃ ) assigned to the third motor connection (W).
• 10 shows the system according to the invention 1 with three branches according to the invention according to the 6 , 8th and 9 .
• 11 equals to 6 However, the limitation is implemented in a different way.
• 12 equals to 8th However, the limitation may be in a manner other than that provided for in 11 he follows.
• 13 equals to 9 However, the limitation may be in a manner other than that provided for in 11 and 12 he follows.
• 14 equals to 6 However, no sign extraction takes place.
• 15 equals to 8th However, no sign extraction takes place.
• 16 equals to 9 However, no sign extraction takes place.
• 17 equals to 6 where a switch can now prevent the control and freeze the default value.
• 18 equals to 8th where a switch can now prevent the control and freeze the default value.
• 19 equals to 9 where a switch can now prevent the control and freeze the default value.
• 20 represents the process for pre-parameterization in the production of a system according to the invention and for reloading the values during operation.

The invention is explained in more detail below with reference to the figures, which do not correspond to the prior art. With regard to the claimed scope of this disclosure, the claims alone are decisive.

• Zum ersten ist es möglich mit Hilfe eines ersten Begrenzers (B_U) nur positive Signalanteile des korrigierten Spannungssignals (U_korr) des ersten Motoranschlusses (U) zum ersten Integrator (Int1U) durchzuschalten und ansonsten dem ersten Integrator (Int_1U) durch den ersten Begrenzer (B_U) einen Null-Wert liefern zu lassen. (Dies ist in 6 dargestellt.)
• Zum anderen ist es möglich, mit Hilfe eines später noch erläuterten ersten Vorzeichensignals (Sig_U), das das Vorzeichen des korrigierten Spannungssignals (U_korr) des ersten Motoranschlusses (U) widergibt und eines ersten Kommutierungsintervallsignals (P_U) ein erstes Integratorsteuersignal (IntCtr_U) zu erzeugen. Dieses steuert den ersten Integrator (Int_1U) in der Art, dass er zum ersten in dem dritten Kommutierungsintervall (Φ₃) den ersten Integrator auf null setzt, wenn das korrigierte Spannungssignal (U_korr) des ersten Motoranschlusses (U) positiv ist und eine Integration der mit -1 multiplizierten korrigierten Spannungssignals (U_korr) des ersten Motoranschlusses (U) durch den ersten Integrator (Int_1U) veranlasst, wenn das korrigierte Spannungssignal (U_korr) des ersten Motoranschlusses (U) negativ ist und
• zum zweiten in dem sechsten Kommutierungsintervall (Φ₆) den ersten Integrator auf null setzt, wenn das korrigierte Spannungssignal (U_korr) des ersten Motoranschlusses (U) negativ ist und eine Integration des mit +1 multiplizierten korrigierten Spannungssignals (U_korr) des ersten Motoranschlusses (U) durch den ersten Integrator (Int_1U) veranlasst, wenn das korrigierte Spannungssignal (U_korr) des ersten Motoranschlusses (U) positiv ist.

6 shows an exemplary sub-device according to the invention for determining the first commutation signal (A ₁ ) for the commutation at the first motor connection (U). This is a first branch (ZW ₁ ) of the EMF evaluation (EMKA) of the 1 and 10 In this respect, the 3 described sub-device is replaced by this new sub-device according to the invention in at least one branch of the EMF evaluation (EMKA), which typically contains such a branch for each motor connection (U, V, W). In a first stage of the sub-device according to the invention, a virtual star point signal (SpS) is again generated from the three voltages of the three motor connections (U, V, W) by means of the already known and unchanged star connection of three voltage dividers (SpT ₁ , SpT ₂ , SpT ₃ ). This virtual star point voltage (SpS) is again, as before, subtracted from the voltage at the first motor connection (U) by means of the known second summer (SU _2U ). The corrected voltage signal (U _korr ) of the first motor connection (U) thus obtained is integrated again in a first integrator (Int _1U ). If necessary, in a special embodiment of the invention, the integrator can also be designed as a filter here. Preferably, the first integrator (Int _1U ) integrates only positive values of the corrected voltage signal (U _korr ) of the first motor connection (U) in the commutation intervals (Φ ₁ to Φ ₆ ) in which the associated half-bridge of the first motor connection (U) has a high resistance. In the example described here, these are the third commutation interval (Φ ₃ ) and the sixth commutation interval (Φ ₆ ). The first integrator (Int _1U ) is typically reset immediately before or at the beginning of such a commutation interval (Φ ₃ , Φ ₆ ), for example by the control block (St) or another controller. There are two options for integrating only the positive values of the corrected voltage signal (U _korr ) of the first motor connection (U):

• Firstly, it is possible to use a first limiter (B _U ) to switch only positive signal components of the corrected voltage signal (U _korr ) of the first motor connection (U) through to the first integrator (Int1U) and otherwise to have the first integrator (Int _1U ) receive a zero value through the first limiter (B _U ). (This is shown in 6 shown.)
• On the other hand, it is possible to generate a first integrator control signal (IntCtr _U ) with the aid of a first sign signal (Sig _U ) explained later, which reflects the sign of the corrected voltage signal (U _korr ) of the first motor connection (U) and a first commutation interval signal (P _U ). This controls the first integrator (Int _1U ) in such a way that it first sets the first integrator to zero in the third commutation interval (Φ ₃ ) if the corrected voltage signal (U _korr ) of the first motor connection (U) is positive and causes an integration of the corrected voltage signal (U _korr ) of the first motor connection (U) multiplied by -1 by the first integrator (Int _1U ) if the corrected voltage signal (U _korr ) of the first motor connection (U) is negative and
• secondly, in the sixth commutation interval (Φ ₆ ), the first integrator is set to zero if the corrected voltage signal (U _korr ) of the first motor connection (U) is negative and the corrected voltage signal (U _korr ) of the first motor connection (U) multiplied by +1 is integrated by the first integrator (Int _1U ) if the corrected voltage signal (U _korr ) of the first motor connection (U) is positive.

(This is shown in Figure 11 as a variant of Figure 6.)

Tests have shown that the use of the first limiter (B _U ) is particularly preferable.

The first threshold signal (S _2U ) is again obtained as the output of the first integrator (Int _1U ), which is already known from the prior art. A comparator, more precisely a fourth comparator according to the invention (CMP _2U ), does not compare this first threshold signal (S _1U ), as in the prior art, with the said first specified value (V _refU ) for the commutation, which had to be determined experimentally, but with a first specified value (V _U ) according to the invention, which is determined by the sub-device itself, which represents the core of the invention. This will be discussed in more detail later. The fourth comparator (CMP _2U ) now generates the first commutation signal (A ₁ ), which is used as described in the said control block (St) for the timely commutation of the first half-bridge, which supplies current to the first motor connection (U). In a special embodiment of the invention, the fourth comparator (CMP _2U ) preferably has a hysteresis.

In contrast to the prior art, the partial device according to the invention has a first sign unit (Sgn _U ) which determines the sign of the corrected voltage signal (U _korr ). This determined sign is output by the first sign unit (Sgn _U ) as the first sign signal (Sig _U ). A fourth integrator (Int _2U ) integrates when the first half-bridge is in the third state and during the third and sixth commutation intervals (Φ ₃ , Φ ₆ ) this sign. The integration is reset to zero at the beginning of the commutation interval (Φ ₃ , Φ ₆ ). The value of the integration can be adjusted before output with a first constant factor (F _U ) to set the transient response by a multiplier contained in the fourth integrator (Int _2U ). This results in the first integrated sign signal (S _2U ). The current first specified value (V _U ) according to the invention is added to this first integrated sign signal (S _2U ) by a third summer (SU _3U ) for the first motor connection (U). This results in the first reload value (S _3U ) for the first specified value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation. This is saved by a first sample and hold circuit (SaH _U ) when the first commutation signal (A ₁ ) has an edge.

Preferably, the rising and falling edge of the first commutation signal (A ₁ ) is evaluated. Instead, however, the fourth integrator (Int _2U ) can also form the first integrated sign signal (S _2U ) with a positive multiplication factor of 1 in the third commutation interval (Φ ₃ ) and the first integrated sign signal (S _2U ) with a negative multiplication factor of -1 in the sixth commutation interval (Φ ₆ ). The value of the integration can be adjusted before output with a first constant factor (F _U ) to set the transient response by a multiplier contained in the fourth integrator (Int _2U ). At the same time, the first integrator (Int _1U ) preferably forms the first threshold signal (S _1U ) with a positive multiplication factor of 1 in the third commutation interval (Φ ₃ ) and the first threshold signal (S _1U ) with a negative multiplication factor of -1 in the sixth commutation interval (Φ ₆ ). In this case, the rising edge of the first commutation signal (A ₁ ) is always evaluated. Another possibility is that the output of the fourth integrator (Int _2U ) has an absolute value generator, so that the fourth integrator (Int _2U ) only outputs the amount with a positive sign. Even then, the positive edge of the first commutation signal (A ₁ ) is preferably evaluated during the transition from the sixth commutation interval (Φ ₆ ) to the first commutation interval (Φ ₁ ) or during the transition from the third commutation interval (Φ ₃ ) to the fourth commutation interval (Φ ₄ ).

The output of the first sample and hold circuit (SaH _U ) represents the current first preset value (V _U ) according to the invention, which is used by the fourth comparator (CMP _2U ) to form the first commutation signal (A ₁ ). The first reload value (S _3U ) for the new first preset value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation on the one hand and the first preset value (V _U ) according to the invention on the other hand differ by the first temporary change value (ΔV _U ).

7 shows firstly the voltage at the first motor connection (U) when the associated half-bridge of the control block (St) is in the high-impedance third state, for different values of the first preset value (V _u ) according to the invention and secondly the voltage curve of the first threshold signal (S _1U ) and thirdly the voltage curve of the first integrated sign signal (S _2U ) for these cases.

On the left, commutation is shown which occurs too early. In this case, the first preset value (V _U ) according to the invention is too small. The first temporary change value (ΔV _U ) is positive and is added to the first preset value (V _U ) according to the invention. The first recharge value (S _3U ) determined in this way is then transferred to the first sample and hold circuit (SaH _U ) at the next commutation, i.e. at an edge on the first commutation signal (A ₁ ), and is thus used from that point on as the new first preset value (V _U ), whereby this first preset value (V _U ) is tracked, which distinguishes this sub-device from the prior art with first preset values (V _refU ) which are predetermined experimentally.

In the middle, a commutation that is too late is shown. In this case, the first preset value (V _U ) according to the invention is too large. The first temporary change value (ΔV _U ) is negative and is added to the first preset value (V _U ) according to the invention. The first recharge value (S _3U ) determined in this way is then taken over again at the next commutation, i.e. at an edge on the first commutation signal (A ₁ ) in the first sample and hold circuit (SaH _U ) and thus used from that point on as the new first preset value (V _U ), whereby this first preset value (V _U ) is also tracked in this case, which also distinguishes this sub-device from the prior art with first preset values (V _refU ) that are to be predetermined experimentally.

If the first integrated sign signal (S _2U ) is zero at the end of the third or sixth commutation interval (Φ ₃ , Φ ₆ ), the zero crossing of the EMF is located in the middle of the third or sixth commutation interval (Φ ₃ , Φ ₆ ), as desired.

8th shows an exemplary sub-device according to the invention for determining the second commutation signal (A ₂ ) for the commutation at the second motor connection (V). This is a second branch (ZW ₂ ) of the EMF evaluation (EMKA) of the 1 and 10 In this respect, the 3 described sub-device is replaced by this new sub-device according to the invention in at least the second branch (ZW ₂ ) of the EMF evaluation (EMKA), which typically contains such a branch for each motor connection (U, V, W). In a first stage of the sub-device according to the invention, a virtual star point signal (SpS) is again generated from the three voltages of the three motor connections (U, V, W) by means of the already known and unchanged star connection of three voltage dividers (SpT ₁ , SpT ₂ , SpT ₃ ). This circuit part can be used together with the first branch (ZW ₁ ). This virtual star point voltage (SpS) is again, as before, subtracted from the voltage at the second motor connection (V) by means of the known associated second summer (SU _2V ). The corrected voltage signal (V _korr ) of the second motor connection (V) thus obtained is integrated again in a first integrator (Int _1V ). If necessary, in a special version of the invention, the integrator can again be designed as a filter.

• Zum ersten ist es möglich mit Hilfe eines zweiten Begrenzers (B_V) nur positive Signalanteile des korrigierten Spannungssignals (V_korr) des zweiten Motoranschlusses (V) zum zweiten Integrator (Int_1V) durchzuschalten und ansonsten dem zweiten Integrator (Int_1V) durch den zweiten Begrenzer (B_V) einen Nullwert liefern zu lassen. (Dies ist in 8 dargestellt.)
• Zum anderen ist es möglich, mit Hilfe eines später noch erläuterten zweiten Vorzeichensignals (Sig_V), das das Vorzeichen des korrigierten Spannungssignals (V_korr) des zweiten Motoranschlusses (V) widergibt und eines zweiten Kommutierungsintervallsignals (P_V) ein zweites Integratorsteuersignal (IntCtr_V) zu erzeugen. Dieses steuert den zweiten Integrator (Int_1V) in der Art, dass er zum ersten in dem ersten Kommutierungsintervall (Φ₁) den zweiten Integrator (Int_1V) auf null setzt, wenn das korrigierte Spannungssignal (V_korr) des zweiten Motoranschlusses (V) positiv ist und eine Integration des mit -1 multiplizierten korrigierten Spannungssignals (V_korr) des zweiten Motoranschlusses (V) durch den zweiten Integrator (Int_1V) veranlasst, wenn das korrigierte Spannungssignal (V_korr) des zweiten Motoranschlusses (V) negativ ist und
• zum zweiten in dem vierten Kommutierungsintervall (Φ₄) den zweiten Integrator auf null setzt, wenn das korrigierte Spannungssignal (V_korr) des zweiten Motoranschlusses (V) negativ ist und eine Integration der mit +1 multiplizierten korrigierten Spannungssignals (V_korr) des zweiten Motoranschlusses (V) durch den zweiten Integrator (Int_1V) veranlasst, wenn das korrigierte Spannungssignal (V_korr) des zweiten Motoranschlusses (V) positiv ist.

Preferably, the second integrator (Int _1V ) integrates only positive values of the corrected voltage signal (V _korr ) of the second motor connection (V) in the commutation intervals (Φ ₁ to Φ ₆ ) in which the associated half-bridge of the second motor connection (V) is high-resistance. In the example described here, these are the first commutation interval (Φ ₁ ) and the fourth commutation interval (Φ ₄ ). The second integrator (int _1V ) is typically reset immediately before or at the beginning of such a commutation interval (Φ ₁ , Φ ₄ ), for example by the control block (St) or another controller. In order to integrate only the positive values of the corrected voltage signal (V _korr ) of the second motor connection (V), there are again two options, for example:

• Firstly, it is possible to use a second limiter (B _V ) to switch only positive signal components of the corrected voltage signal (V _corr ) of the second motor connection (V ) to the second integrator (Int _1V ) and otherwise to have the second integrator (Int _1V ) deliver a zero value through the second limiter (B _V ). (This is shown in 8th shown.)
• On the other hand, it is possible to generate a second integrator control signal (IntCtr _V ) with the aid of a second sign signal (Sig _V ) explained later, which reflects the sign of the corrected voltage signal (V _korr ) of the second motor connection (V) and a second commutation interval signal (P _V ). This controls the second integrator (Int _1V ) in such a way that it first sets the second integrator (Int _1V ) to zero in the first commutation interval (Φ ₁ ) if the corrected voltage signal (V _korr ) of the second motor connection (V) is positive and causes an integration of the corrected voltage signal (V _korr ) of the second motor connection (V) multiplied by -1 by the second integrator (Int _1V ) if the corrected voltage signal (V _korr ) of the second motor connection (V) is negative and
• secondly, in the fourth commutation interval (Φ ₄ ), setting the second integrator to zero if the corrected voltage signal (V _korr ) of the second motor connection (V) is negative and causing an integration of the corrected voltage signal (V _korr ) of the second motor connection (V) multiplied by +1 by the second integrator (Int _1V ) if the corrected voltage signal (V _korr ) of the second motor connection (V) is positive.

(This is shown in Figure 12 as a variant of Figure 8.)

Tests have shown that the use of the second limiter (B _V ) is particularly preferable.

The second threshold signal (S _1V ) is again obtained as the output of the second integrator (Int _1V ), which is already known from the prior art. A comparator, more precisely a fifth comparator according to the invention (CMP _2V ), does not compare this second threshold signal (S _1V ), as in the prior art, with the said second specified value (V _refV ) for the commutation, which had to be determined experimentally, but with a second specified value (V _V ) according to the invention, which is now determined by the sub-device itself, which again represents the core of the invention. The fifth comparator (CMP _2V ) now generates the second commutation signal (A ₂ ), which is used as described in the said control block (St) for the timely commutation of the second half-bridge, which supplies current to the second motor connection (V). In this case, the fifth comparator (CMP _2V ) preferably again has a hysteresis in a special embodiment of the invention.

In contrast to the prior art, the sub-device according to the invention has a second sign unit (Sgn _V ) which determines the sign of the corrected voltage signal (V _korr ). This determined sign is output by the second sign unit (Sgn _V ) as a second sign signal (Sig _V ). A fifth integrator (Int _2V ) integrates when the second half-bridge is in the third state and during the first and fourth commutation intervals (Φ ₁ , Φ ₄ ) to this sign. The integration is reset to zero at the beginning of the commutation interval (Φ ₁ , Φ ₄ ). The value of the integration can be adjusted before output with a second constant factor (F _V ) to set the transient response by a multiplier contained in the fifth integrator (Int _2V ). This results in the second integrated sign signal (S _2V ). The current second preset value (V _V ) according to the invention is added to this second integrated sign signal (S _2V ) by a third summer (SU _3V ) for the second motor connection (V). This results in the second reload value (S _3V ) for the second preset value (V _V ) according to the invention for the commutation of the second motor connection (V) during the next commutation. This is secured by a second sample and hold circuit (SaH _V ) when the second commutation signal (A ₂ ) has an edge. The rising and falling edge of the second commutation signal (A ₂ ) is evaluated. Instead, the fifth integrator (Int _2V ) can also form the second integrated sign signal (S _2V ) with a positive multiplication factor of 1 in the first commutation interval (Φ ₁ ) and the second integrated sign signal (S _2V ) with a negative multiplication factor of -1 in the fourth commutation interval (Φ ₄ ). The value of the integration can be adjusted before output with a second constant factor (F _V ) to set the transient response by a multiplier contained in the fifth integrator (Int _2V ). At the same time, the second integrator (Int _1V ) then preferably forms the second threshold signal (S _1V ) with a positive multiplication factor of 1 in the first commutation interval (Φ ₁ ) and the second threshold signal (S _1V ) with a negative multiplication factor of -1 in the fourth commutation interval (Φ ₄ ). In this case, the rising edge of the second commutation signal (A ₂ ) is always evaluated. Another possibility is that the output of the fifth integrator (Int _2V ) has an absolute value generator, so that the fifth integrator (Int _2V ) only outputs the amount with a positive sign. In this case, too, the positive edge of the second commutation signal (A ₂ ) is preferably evaluated at the transition from the first commutation interval (Φ ₁ ) to the second commutation interval (Φ ₂ ) or at the transition from the fourth commutation interval (Φ ₄ ) to the fifth commutation interval (Φ ₅ ).

The output of the second sample and hold circuit (SaH _V ) represents the current second preset value (V _V ) according to the invention, which is used by the fifth comparator (CMP _2V ) to form the second commutation signal (A ₂ ). The second recharge value (S _3V ) for the new second preset value (V _V ) according to the invention for the commutation of the second motor connection (V ) during the next commutation on the one hand and the second preset value (V _V ) according to the invention on the other hand differ by the second temporary change value (ΔV _V ).

9 shows an exemplary sub-device according to the invention for determining the third commutation signal (A ₃ ) for the commutation at the third motor connection (W). This is a third branch (ZW ₃ ) of the EMF evaluation (EMKA) of the 1 and 10 In this respect, the 3 described sub-device is replaced by this new sub-device according to the invention in at least the third branch (ZW ₃ ) of the EMF evaluation (EMKA), which typically contains such a branch for each motor connection (U, V, W). In a first stage of the sub-device according to the invention, a virtual star point signal (SpS) is again generated from the three voltages of the three motor connections (U, V, W) by means of the already known and unchanged star connection of three voltage dividers (SpT ₁ , SpT ₂ , SpT ₃ ). This circuit part can be used together with the first branch (ZW ₁ ). This virtual star point voltage (SpS) is again, as before, subtracted from the voltage at the third motor connection (W) by means of the known associated second summer (SU _2W ). The corrected voltage signal (W _korr ) of the third motor connection (W) thus obtained is integrated again in a first integrator (Int _1W ). If necessary, in a special version of the invention, the integrator can again be designed as a filter.

• Zum ersten ist es möglich mit Hilfe eines dritten Begrenzers (B_W) nur positive Signalanteile des korrigierten Spannungssignals (W_korr) des zweiten Motoranschlusses (W) zum dritten Integrator (Int_1W) durchzuschalten und ansonsten dem dritten Integrator (Int_1W) durch den dritten Begrenzer (B_W) einen Nullwert liefern zu lassen. (Dies ist in 9 dargestellt.)
• Zum anderen ist es möglich, mit Hilfe eines später noch erläuterten dritten Vorzeichensignals (Sig_W), das das Vorzeichen des korrigierten Spannungssignals (W_korr) des dritten Motoranschlusses (W) widergibt und eines dritten Kommutierungsintervallsignals (P_W) ein drittes Integratorsteuersignal (IntCtr_W) zu erzeugen. Dieses steuert den dritten Integrator (Int_1W) in der Art, dass er zum ersten in dem fünften Kommutierungsintervall (Φ₅) den dritten Integrator (Int_1W) auf null setzt, wenn das korrigierte Spannungssignal (W_korr) des dritten Motoranschlusses (W) positiv ist und eine Integration des mit -1 multiplizierten korrigierten Spannungssignals (W_korr) des dritten Motoranschlusses (W) durch den dritten Integrator (Int_1w) veranlasst, wenn das korrigierte Spannungssignal (W_korr) des dritten Motoranschlusses (W) negativ ist und
• zum zweiten in dem zweiten Kommutierungsintervall (Φ₂) den dritten Integrator auf null setzt, wenn das korrigierte Spannungssignal (W_korr) des dritten Motoranschlusses (W) negativ ist und eine Integration der mit +1 multiplizierten korrigierten Spannungssignals (W_korr) des dritten Motoranschlusses (W) durch den dritten Integrator (Int_1W) veranlasst, wenn das korrigierte Spannungssignal (W_korr) des dritten Motoranschlusses (W) positiv ist.

Preferably, the third integrator (Int _1W ) only integrates positive values of the corrected voltage signal (W _korr ) of the third motor connection (W) in the commutation intervals (Φ ₁ to Φ ₆ ) in which the associated half-bridge of the third motor connection (W) is high-resistance. In the example described here, these are the fifth commutation interval (Φ ₅ ) and the second commutation interval (Φ ₂ ). The third integrator (Int _1W ) is typically reset immediately before or at the beginning of such a commutation interval (Φ ₅ , Φ ₂ ), for example by the control block (St) or another controller. In order to integrate only the positive values of the corrected voltage signal (W _korr ) of the third motor connection (W), there are again two options:

• Firstly, it is possible to use a third limiter (B _W ) to switch only positive signal components of the corrected voltage signal (W _korr ) of the second motor connection (W) to the third integrator (Int _1W ) and otherwise to have the third integrator (Int _1W ) receive a zero value through the third limiter (B _W ). (This is shown in 9 shown.)
• On the other hand, it is possible to generate a third integrator control signal (IntCtr _W ) with the aid of a third sign signal (Sig _W ) explained later, which reflects the sign of the corrected voltage signal (W _korr ) of the third motor connection (W) and a third commutation interval signal (P _W ). This controls the third integrator (Int _1W ) in such a way that it first sets the third integrator (Int _1W ) to zero in the fifth commutation interval (Φ ₅ ) if the corrected voltage signal (W _korr ) of the third motor connection (W) is positive and causes an integration of the corrected voltage signal (W _korr ) of the third motor connection (W) multiplied by -1 by the third integrator (Int _1w ) if the corrected voltage signal (W _korr ) of the third motor connection (W) is negative and
• secondly, in the second commutation interval (Φ ₂ ), the third integrator is set to zero if the corrected voltage signal (W _korr ) of the third motor connection (W) is negative and the corrected voltage signal (W _korr ) of the third motor connection (W) multiplied by +1 is caused to be integrated by the third integrator (Int _1W ) if the corrected voltage signal (W _korr ) of the third motor connection (W) is positive.

(This is shown in Figure 13 as a variant of Figure 9.)

Tests have shown that the use of the third limiter (B _W ) is particularly preferable.

The third threshold signal (S _1W ) is again obtained as the output of the third integrator (Int _1W ), which is already known from the prior art. A comparator, more precisely a sixth comparator according to the invention (CMP _2W ), does not compare this third threshold signal (S _1W ), as in the prior art, with the said third specified value (V _refV ) for the commutation, which had to be determined experimentally, but with a third specified value (V _W ) according to the invention, which is now determined by the sub-device itself, which again represents the core of the invention. The sixth comparator (CMP _2W ) now generates the third commutation signal (A ₃ ), which is used as described in the said control block (St) for the timely commutation of the third half-bridge, which supplies current to the third motor connection (W). In this case, the sixth comparator (CMP ₂₃ ) preferably again has a hysteresis in a special embodiment of the invention.

In contrast to the prior art, the sub-device according to the invention, the third branch (ZW ₃ ), has a third sign unit (Sgn _W ) which determines the sign of the corrected voltage signal (W _korr ). This determined sign is output by the third sign unit (Sgn _W ) as a third sign signal (Sig _W ). A sixth integrator (Int _2W ) integrates when the third half-bridge is in the third state and during the second and fifth commutation intervals (Φ ₂ , Φ ₅ ) this sign. The integration is reset to zero at the beginning of the commutation interval (Φ ₂ , Φ ₅ ). The value of the integration can be adjusted before output with a third constant factor (F _V ) to set the transient response by a multiplier contained in the sixth integrator (Int _2V ). This results in the third integrated sign signal (S _2W ). The current third preset value (V _W ) according to the invention is added to this third integrated sign signal (S _2W ) by a third summer (SU _3W ) for the third motor connection (W). This results in the third reload value (S _3W ) for the third preset value (V _W ) according to the invention for the commutation of the third motor connection (W) during the next commutation. This is secured by a third sample and hold circuit (SaH _W ) when the third commutation signal (A ₃ ) has an edge.

Preferably, the rising and falling edge of the third commutation signal (A ₁ ) is evaluated. Instead, however, the sixth integrator (Int _2W ) can also form the third integrated sign signal (S _2W ) with a positive multiplication factor of 1 in the fifth commutation interval (Φ ₅ ) and the third integrated sign signal (S _2W ) with a negative multiplication factor of -1 in the second commutation interval (Φ ₂ ). The value of the integration can be adjusted before output with a third constant factor (F _V ) to set the transient response by a multiplier contained in the sixth integrator (Int _2V ). At the same time _, the third integrator (Int _1W ) preferably forms the third threshold signal (S _1W ) with a positive multiplication factor of 1 in the fifth commutation interval (Φ ₅ ) and the third threshold signal (S _1W ) with a negative multiplication factor of -1. In this case, the rising edge of the third commutation signal (A ₃ ) is always evaluated at the transition from the second commutation interval (Φ ₂ ) to the third commutation interval (Φ ₃ ) or at the transition from the fifth commutation interval (Φ ₅ ) to the sixth commutation interval (Φ ₆ ). Another possibility is that the output of the sixth integrator (Int _2W ) has an absolute value generator, so that the sixth integrator (Int _2W ) only outputs the amount with a positive sign. In this case, too, the positive edge of the third commutation signal (A ₃ ) is preferably evaluated.

The output of the third sample and hold circuit (SaH _W ) represents the current third preset value (V _W ) according to the invention, which is used by the sixth comparator (CMP _2W ) to form the third commutation signal (A ₃ ). The third recharge value (S _3W ) for the new third preset value (V _W ) according to the invention for the commutation of the third motor connection (W) during the next commutation on the one hand and the third preset value (V _W ) according to the invention on the other hand differ by the third temporary change value (ΔV _W ).

10 shows 1 with the three branches (ZW ₁ , ZW ₂ , ZW ₃ ). The control block (St) or another control activates the integration in the integrators of the branch whose associated half-bridge on the associated motor connection (U, V, W) is currently in the high-impedance phase in the relevant commutation interval (Φ ₁ to Φ ₆ ). As previously explained, the states of the commutation signals (A ₁ , A ₂ , A ₃ ) reflect the current commutation interval (Φ ₁ to Φ ₆ ) in the form of a binary logic vector.

The 11 to 13 have already been mentioned above.

14 shows a variant of the 6 whereby the corrected voltage signal (U _corr ) of the first motor connection (U) serves directly as input signal for the fourth integrator (Int _2U ).

15 shows a variant of the 8th wherein the corrected voltage signal (V _corr ) of the second motor terminal (V) serves directly as an input signal for the fifth integrator (Int _2V ).

16 shows a variant of the 9 whereby the corrected voltage signal (W _corr ) of the third motor terminal (W) serves directly as an input signal for the sixth integrator (Int _2W ).

17 represents a further preferred embodiment of the invention using the example of the first branch (ZW1). Once the method described above for automatically determining the first preset value (V _U ) according to the invention has reached a stable first preset value (V _U ) according to the invention, this no longer changes. This means that the lower branch of the control of the first preset value (V _U ) according to the invention, consisting of the first sign unit (Sgn _U ), the fourth integrator (Int _2U ) and the third summer (SU _2U ), which is assigned to the first motor connection (U), is no longer required. It is therefore possible in a special embodiment of the invention, e.g. after the automatic adjustment has taken place, to switch off the clock of the associated first sample-and-hold circuit (SaH _U ) so that its output signal, the first preset value (V _U ) according to the invention, remains at the value that has been reached and is as stable as possible. For this purpose, in 17 an additional first switch (SW _U ) is inserted into the connection between the first commutation signal (A ₁ ) and the trigger input of the first sample-and-hold circuit (SaH _U ). With this first switch (SW _U ) it is then possible to switch between the two states "automatic parameterization" and "normal motor operation". The automatic parameterization takes place, for example, after the system is switched on when the motor is started for the first time or on request.

For this purpose, the system according to the invention has a system controller (SSt), which typically comprises a finite state machine as a sequence controller and/or a microprocessor with memory and which generates the precharge value (V ₀ ) for the respectively assigned sample and hold circuits (SaH _U , SaH _V , SaH _W ) by means of one or more analog-to-digital converters and possibly further sample and hold circuits. This precharge value (V ₀ ) can optionally also be generated in the form of three respectively assigned separate precharge values (V _U , V _V , V _W ) specifically for the respective branch (ZW1, ZW2, ZW3). In addition, the system controller (SSt) evaluates the state of the respective inventive default value (V _U , V _V , V _W ), in this case the first inventive default value (V _U ). This can be done, for example, by digital-to-analog conversion and evaluation of the digitized signal curve of the respective inventive default value (V _U , V _V , V _W ), in this case the first inventive default value (V _U ). If the inventive first default value (V _U ) fluctuates between two or more than two engine revolutions by less than 25%, better less than 12%, better less than 6%, better less than 2%, better less than 1%, the system control (SSt) opens the first switch (SW _U ).

However, after switching off the supply voltage, the system would lose the first default value according to the invention (V _U ) and would have to be parameterized again the next time it is switched on again.

It is therefore sensible if the first preset value (V _U ) according to the invention is saved in a non-volatile, preferably digital memory, preferably within the system control (SSt), and is used as the first precharge value (V _0U ) when the system is restarted as a replacement for the precharge value (V ₀ ). The non-volatile memory takes over the first precharge value (V _U ) according to the invention when the first switch (SW _U ) is opened and, for example in the case of a non-volatile memory, can also be able to store this determined, first precharge value (V _U ) according to the invention as the first precharge value (V _0U ) even after the power supply has been switched off.

This then enables, for example, the one-time automatic parameterization of the device according to the invention in conjunction with a specific motor at the end of a production line. Each time the system is restarted, the first precharge value (V _0U ) determined in this way, for example at the end of production, is read directly from the non-volatile memory and the system can start directly without a new automatic adjustment.

18 This further preferred embodiment of the invention is now illustrated using the example of the second branch (ZW2). If the method described above for automatically determining the second preset value (V _V ) according to the invention has again reached a stable second preset value (V _V ), this also no longer changes. This means that the lower branch of the control of the second preset value (V _V ) according to the invention, consisting of the second sign unit (Sgn _V ), the fifth integrator (Int _2V ) and the third summer (SU _2V ), which is assigned to the second motor connection (V), is no longer required. In a special embodiment of the invention, it is therefore possible, e.g. after the automatic adjustment has taken place, to switch off the clock of the associated second sample and hold circuit (SaH _V ) so that its output signal, the second preset value (V _V ) according to the invention, remains at the value that has been reached and is as stable as possible. For this purpose, 18 an additional second switch (SW _U ) is inserted into the connection between the second commutation signal (A ₂ ) and the trigger input of the second sample-and-hold circuit (SaH _V ). With this second switch (SW _V ) it is then possible to switch between the two states "automatic parameterization" and "normal motor operation". The automatic parameterization takes place, for example, after the system is switched on when the motor is started for the first time or on request, typically analogous to the first branch (ZW1)

Typically, the system control (SSt) evaluates the state of the second inventive preset value (V _V ). This can be done, for example, by digital-to-analog conversion and evaluation of the thus digitized signal curve of the second inventive preset value (V _V ). If the second inventive preset value (V _U ) fluctuates between two or more than two engine revolutions by less than 25%, preferably less than 12%, preferably less than 6%, preferably less than 2%, preferably less than 1%, the system control (SSt) opens the second switch (SW _V ).

However, after switching off the supply voltage, the system would also lose the second inventive default value (V _V ) and would have to be parameterized again the next time it is switched on again.

It is therefore sensible if the second preset value (V _V ) according to the invention is saved in a non-volatile, preferably digital memory, preferably within the system control (SSt), and is used as a second precharge value (V _0V ) when the system is restarted as a replacement for the precharge value (V ₀ ). The non-volatile memory takes over the second precharge value (V _V ) according to the invention when the second switch (SW _V ) is opened and, for example in the case of a non-volatile memory, can also be able to store this determined second precharge value (V _V ) according to the invention as a second precharge value (V _0V ) even after the power supply has been switched off.

This then enables, for example, the one-time automatic parameterization of the device according to the invention in conjunction with a specific motor at the end of a production line. Each time the system is restarted, the parameterization determined in this way, for example at the end of production, is The determined second precharge value (V _0V ) is read directly from the non-volatile memory and the system can start directly without another automatic adjustment.

19 This further preferred embodiment of the invention is now illustrated using the example of the third branch (ZW3). If the method described above for automatically determining the third preset value (V _W ) according to the invention has again reached a stable third preset value (V _W ) according to the invention, this also no longer changes. This means that the lower branch of the control of the third preset value (V _W ) according to the invention, consisting of the third sign unit (Sgn _W ), the sixth integrator (Int _2W ) and the third summer (SU _2W ), which is assigned to the third motor connection (W), is also no longer required. It is therefore also possible in this particular embodiment of the invention, e.g. after the automatic adjustment has taken place, to switch off the clock of the associated third sample and hold circuit (SaH _W ) here too, so that its output signal, the third preset value (V _W ) according to the invention, remains at the value that has been reached and is as stable as possible. For this purpose, 19 an additional third switch (SW _W ) is inserted into the connection between the third commutation signal (A ₃ ) and the trigger input of the third sample-and-hold circuit (SaH _W ). With this third switch (SW _W ) it is then possible to switch between the two states "automatic parameterization" and "normal motor operation". The automatic parameterization takes place, for example, after the system is switched on when the motor is started for the first time or on request, analogously to the first branch (ZW1) and/or the second branch (ZW2).

The system control (SSt) again typically evaluates the state of the third inventive preset value (V _W ). This can be done, for example, by digital-to-analog conversion and evaluation of the thus digitized signal curve of the third inventive preset value (V _W ). If the third inventive preset value (V _W ) fluctuates between two or more than two engine revolutions by less than 25%, preferably less than 12%, preferably less than 6%, preferably less than 2%, preferably less than 1%, the system control (SSt) opens the third switch (SW _W ).

However, after switching off the supply voltage, the system would lose the third inventive default value (V _W ) as well as the other two inventive default values (V _U , V _V ) and would have to carry out a new parameterization the next time it is switched on again.

It is therefore sensible if the third inventive preset value (V _W ) is saved in a non-volatile, preferably digital memory, preferably within the system control (SSt), and is used as the third precharge value (V _0W ) when the system is restarted as a replacement for the precharge value (V ₀ ). The non-volatile memory takes over the third inventive precharge value (V _W ) when the second switch (SW _V ) is opened and, for example in the case of a non-volatile memory, can also be able to store this determined third inventive precharge value (V _W ) as the third precharge value (V _0W ) even after the power supply has been switched off.

This then enables, for example, the one-time automatic parameterization of the device according to the invention in conjunction with a specific motor at the end of a production line. Each time the system is restarted, the third precharge value (V _0W ) determined in this way, for example at the end of production, is read directly from the non-volatile memory and the system can start directly without a new automatic adjustment.

It should be noted that it is also possible to set up the system with only one lower control branch, for example consisting of the first sign unit (Sgn _U ), the fourth integrator (Int _2U ) and the third summer (SU _2U ) for the first motor connection (U) or consisting of the second sign unit (Sgn _V ), the fifth integrator (Int _2V ) and the third summer (SU _2V ) for the second motor connection (V) or consisting of the third sign unit (Sgn _W ), the sixth integrator (Int _2W ) and the third summer (SU _2W ) for the third motor connection (W) and to use the respectively determined default value (V _U , V _V , V _W ) directly for the other motor connections (U, V, W) as substitute inventive default values (V _U , V _V , V _W ).

20 shows the process for using a device according to the invention. The system control (SSt) or the control block (St), which can expressly take over the function of the system control (SSt) if necessary, determines that the system has not been supplied with energy in the meantime, and has therefore probably been switched on. This is the start of the process, the first process step (1).

Next, in the second process step (2), the system control (SSt) determines whether a valid parameterization exists. For the sake of explanation, it is initially assumed that this is not the case.

In this case, the system switches to a third process step (3) to precharge the sample and hold circuits (SaH _U , SaH _V , SaH _W ) with the precharge value (V ₀ ), which is typically stored in the program of a microprocessor within the system control (SSt). This gives the entire system meaningful starting values in order to be able to adjust at all. The switches (SW _U , SW _V , SW _W ) are typically also closed at this time.

The system is now able to determine the inventive default values (V _U , V _V , V _W ) itself. This takes place in the next fourth process step (4), in which these inventive default values (V _U , V _V , V _W ) are regulated and thus determined. If the quality of the obtained inventive default values (V _U , V _V , V _W ) is sufficient, which is typically the case if their fluctuations are small enough, the system control (SSt) switches to the next, fifth process step (5).

In the fifth process step (5), the system control (SSt) saves the values of the inventive default values (V _U , V _V , V _W ) determined in this way in a memory. This is preferably a digital non-volatile memory, which is why the system control (SSt) preferably has one or more digital-to-analog converters in order to be able to digitize these values of the inventive default values (V _U , V _V , V _W ).

In a subsequent sixth process step (6), the respective switches (SW _U , SW _V , SW _W ) are opened. This preferably occurs with a time delay to the edges of the respective associated commutation signal (A ₁ , A ₂ , A ₃ ). This particularly preferably occurs synchronously with one of the other two commutation signals, as this excludes a hazard between the respective commutation signal and the opening of the respective switch. The system then preferably changes to a waiting loop (11).

This waiting loop (11) can be exited in three directions. Firstly, after a predetermined period of time has elapsed, the system control (SSt) can request a new parameterization or a control command from outside the system initiates such a parameterization. In this case, the system control typically switches back to the third process step (3).

Secondly, if certain error conditions exist, a restart of the system can be forced with the start parameters already determined once and at the same time without a new parameterization by switching to the seventh process step (7) and with a new parameterization by switching to the eighth process step (8).

This second branch splits off in the second process step (2), in which the system control (SSt) determines whether a valid parameterization exists. It is now assumed that this is the case.

In this case, in a seventh process step, the system control (SSt) preloads the sample-and-hold circuits (SaH _U , SaH _V , SaH _W ) with the preload values (V _0U , V _0V , V _0W ) determined and located in their memory. At the start of the following eighth process step (8), the system control (SSt) closes the switches (SW _U , SW _V , SW _W ).

The system is now again able to determine the inventive default values (V _U , V _V , V _W ) more precisely for the current operating period on the basis of a previous operation. This takes place if necessary in the next eighth process step (8), in which these inventive default values (V _U , V _V , V _W ) are again regulated and thus determined. If the quality of the inventive default values obtained (V _U , V _V , V _W ) is sufficient, which is typically the case if their fluctuations are small enough, the system control (SSt) switches to the next, ninth process step (9).

In the ninth process step (9), the system control (SSt) saves the newly determined values of the inventive default values (V _U , V _V , V _W ) in a memory. This is preferably the said digital non-volatile memory.

In a subsequent tenth process step (10), the respective switches (SW _U , SW _V , SW _W ) are opened. This preferably takes place, as described, with a time delay to the edges of the associated commutation signal (A ₁ , A ₂ , A ₃ ). The system then preferably changes to the waiting loop (11).

Instead of re-parameterization, the system control (SSt) can also preferably jump directly from the seventh process step (7) to the tenth process step (10).

Advantages of the invention

The invention avoids an experimental determination of the comparison value for commutation by integrating the EMF. The method is thus able to adapt itself to different motors. This also enables automated setting of the parameter when manufacturing products based on it. For example, series variations in the motor to be used can be compensated for. It is also possible to create different products that only differ in terms of the motor used without any additional setting effort.

The invention can be used to control BLDC motors using block commutation in sensorless operation based on the evaluation of the magnetic flux. When using the magnetic flux as an integral of the EMF, in contrast to commutation based on zero crossings, there is no need to compare the angular position with the internal time base. The time base is therefore no longer necessary. Instead, commutation takes place directly on the basis of the EMF curve without any further calculation steps. The method thus offers greater stability and a better response to dynamic changes in the angular velocity of the rotor. However, it requires manual adjustment to the motor used. The invention described here eliminates this disadvantage by carrying out an adjustment automatically.

List of reference symbols

1

first process step

2

second process step

3

third process step

4

fourth process step

5

fifth process step

6

sixth process step

7

seventh process step

8th

eighth process step

9

ninth process step

10

tenth process step

11

eleventh process step

A1

first commutation signal for the control block (St). The first commutation signal is generated by the EMF evaluation (EMKA). The first commutation signal determines the time of the next voltage commutation by the control block (St). The voltage commutation affects the half-bridge of the control block, whose upper and lower switches are connected to the first motor connection (U). The signal is assigned to the first motor connection (U).

A2

second commutation signal for the control block (St). The second commutation signal is generated by the EMF evaluation (EMKA). The second commutation signal determines the time of the next voltage commutation by the control block (St). The voltage commutation affects the half-bridge of the control block, whose upper and lower switches are connected to the second motor connection (V). The signal is assigned to the second motor connection (V).

A3

third commutation signal for the control block (St). The third commutation signal is generated by the EMF evaluation (EMKA). The third commutation signal determines the time of the next voltage commutation by the control block (St). The voltage commutation affects the half-bridge of the control block, whose upper and lower switches are connected to the third motor connection (W). The signal is assigned to the third motor connection (V).

BU

first limiter. The first limiter generates the limited corrected voltage signal (U' _korr ) of the first motor connection (U) from the corrected voltage signal (U _korr ) of the first motor connection (U). In doing so, it sets the limited corrected voltage signal (U' _korr ) of the first motor connection (U) to zero if the corrected voltage signal (U _korr ) of the first motor connection (U) is negative. This limitation can also be inverted if the appropriate sign is selected for all components of the system. It is therefore essential that the limiter only allows one polarity of the corrected voltage signal (U _korr ) of the first motor connection (U) to pass and maps the other polarity to zero. This part of the device is assigned to the first motor connection (U).

BV

second limiter. The second limiter generates the limited corrected voltage signal (V' _corr ) of the second motor connection (V) from the corrected voltage signal (V _corr ) of the second motor connection (V). In doing so, it sets the limited corrected voltage signal (V' _corr ) of the second motor connection (V) to zero if the corrected voltage signal (V _corr ) of the second motor connection (V) is negative. This limitation can also be inverted if the appropriate sign is selected for all components of the system. It is therefore essential that the second limiter only allows one polarity of the corrected voltage signal (V _corr ) of the second motor connection (V) to pass and maps the other polarity to zero. This part of the device is assigned to the second motor connection (V).

BW

third limiter. The third limiter generates the limited corrected voltage signal (W' _corr ) of the third motor connection (W) from the corrected voltage signal (W _corr ) of the third motor connection (W). In doing so, it sets the limited corrected voltage signal (W' _corr ) of the third motor connection (W) to zero if the corrected voltage signal (W _corr ) of the third motor connection (W) is negative. This limitation can also be inverted if the appropriate sign is selected for all components of the system. It is therefore essential that the third limiter only allows one polarity of the corrected voltage signal (W _corr ) of the third motor connection (W) to pass and maps the other polarity to zero. This part of the device is assigned to the third motor connection (W).

CMP1U

The first comparator compares the first threshold signal (S _1U ) with the preset value (V _ref ) for the commutation and generates therefrom a first commutation signal (A ₁ ) which controls the commutation of the half-bridge of the control block (St) which is connected to the first motor connection (U). This part of the device is assigned to the first motor connection (U).

CMP1V

The second comparator compares the second threshold signal (S _1V ) with the preset value (V _ref ) for the commutation and generates therefrom a second commutation signal (A ₂ ) which controls the commutation of the half-bridge of the control block (St) which is connected to the second motor connection (V). This part of the device is assigned to the second motor connection (V).

CMP1W

The third comparator compares the third threshold signal (S _1W ) with the preset value (V _ref ) for the commutation and generates therefrom a third commutation signal (A ₃ ) which controls the commutation of the half-bridge of the control block (St) which is connected to the third motor connection (W). This part of the device is assigned to the third motor connection (W).

CMP2U

The fourth additional comparator according to the invention compares the first threshold signal (S _1U ) with the first preset value (V _U ) for the commutation and generates therefrom as a first output signal (A ₁ ) a first commutation signal (A ₁ ) that controls the commutation. In the case according to the invention, its first output signal, also called the first commutation signal (A ₁ ), triggers the first sample-and-hold circuit (SaH _U ). This part of the device is assigned to the first motor connection (U).

CMP2V

The fifth additional comparator according to the invention compares the second threshold signal (S _1V ) with the second preset value (V _V ) for the commutation and generates therefrom as a second output signal (A ₂ ) a second commutation signal (A ₂ ) which controls the commutation. In the case according to the invention, its second output signal, also called the second commutation signal (A ₂ ), triggers the second sample-and-hold circuit (SaH _V ). This part of the device is assigned to the second motor connection (V).

CMP2W

The sixth additional comparator according to the invention compares the third threshold signal (S _1W ) with the third preset value (V _W ) for the commutation and generates from this a third commutation signal (A ₃ ) as a third output signal (A ₃ ) that controls the commutation. In the case according to the invention, its third output signal, also called the third commutation signal (A ₃ ), triggers the third sample-and-hold circuit (SaH _W ). This part of the device is assigned to the third motor connection (W).

FU

first constant factor (F _U ) for setting the transient response of the first branch (ZW1) by a multiplier contained in the fourth integrator (lnt _2U ). The factor is assigned to the first motor connection (U).

FV

second constant factor (F _V ) for adjusting the transient response of the second branch (ZW2) by a multiplier contained in the fifth integrator (Int _2V ). The factor is assigned to the second motor connection (U).

FW

third constant factor (F _W ) for adjusting the transient response of the third branch (ZW3) by a multiplier contained in the sixth integrator (Int _2w ). The factor is assigned to the third motor connection (W).

ΔVU

first temporary change value for the change of the first specified value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation. The first reload value (S _3U ) for the new first specified value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation on the one hand and the first specified value (V _U ) according to the invention on the other hand differ by this first temporary change value (ΔV _U ). The value is assigned to the first motor connection (U).

ΔVV

second temporary change value for the change of the second specified value (V _V ) according to the invention for the commutation of the second motor connection (V) during the next commutation. The second reload value (S _3V ) for the new second specified value (V _V ) according to the invention for the commutation of the second motor connection (U) during the next commutation on the one hand and the second specified value (V _V ) according to the invention on the other hand differ by this second temporary change value (ΔV _V ). The value is assigned to the second motor connection (V).

ΔVW

third temporary change value for the change in the third specified value (V _W ) according to the invention for the commutation of the third motor connection (U) during the next commutation. The third reload value (S _3W ) for the new third specified value (V _W ) according to the invention for the commutation of the third motor connection (W) during the next commutation on the one hand and the third specified value (V _W ) according to the invention on the other hand differ by this third temporary change value (ΔV _W ). The value is assigned to the third motor connection (W).

EMKA

EMF evaluation. The EMF evaluation generates the commutation signals (A ₁ , A ₂ , A ₃ ) for controlling the commutation time of the half-bridges of the control circuit (St). The commutation signals (A ₁ , A ₂ , A ₃ ) are generated depending on the voltages at the motor connections (U, V, W) and the commutation intervals (Φ ₁ to Φ ₆ ). The first commutation signal (A ₁ ) is generated depending on the connection voltage at the first motor connection (U) in the third commutation interval (Φ ₃ ) and/or in the sixth commutation interval (Φ ₆ ). The second commutation signal (A ₂ ) is generated depending on the connection voltage at the second motor connection (V) in the first commutation interval (Φ ₁ ) and/or in the fourth commutation interval (Φ ₄ ). The third commutation signal (A ₃ ) is generated depending on the connection voltage at the third motor connection (V) in the second commutation interval (Φ ₂ ) and/or in the fifth commutation interval (Φ ₂ ).

Int1U

first integrator. In the prior art, the first integrator forms an associated first threshold signal (S 1U ) by integrating the corrected voltage signal (U _korr ) of the first motor connection (U) or by integrating the limited corrected voltage signal (U' _korr ) of the first motor connection ( _U ). This device part is assigned to the first motor connection (U).

Int1V

second integrator. In the prior art, the second integrator forms an associated second threshold signal (S 1V ) by integrating the corrected voltage signal (V _corr ) of the second motor connection (V) or by integrating the limited corrected voltage signal (V' _corr ) of the second motor connection ( _V ). This device part is assigned to the second motor connection (V).

Int1W

third integrator. In the prior art, the third integrator forms an associated third threshold signal (S 1W ) by integrating the corrected voltage signal (W _korr ) of the third motor connection (W) or by integrating the limited corrected voltage signal (W' _korr ) of the third motor connection ( _W ). This device part is assigned to the third motor connection (W).

Int2U

fourth integrator. The fourth integrator according to the invention forms an associated first integrated sign signal (S _2U ) by integrating the first sign signal (Sig _U ). This part of the device is assigned to the first motor connection (U). The output of the fourth integrator is typically multiplied by -1 to output the first integrated sign signal (S _2U ). The value of the integration can be adjusted before output with a first constant factor (F _U ) to adjust the transient response by a multiplier contained in the fourth integrator (Int _2U ). This part of the device is assigned to the first motor connection (U).

Int2V

fifth integrator. The fifth integrator according to the invention forms an associated second integrated sign signal (S _2V ) by integrating the second sign signal (Sig _V ). This part of the device is assigned to the second motor connection (V). The output of the fifth integrator is typically multiplied by -1 to output the second integrated sign signal (S _2V ). The value of the integration can be adjusted before output with a second constant factor (F _V ) to adjust the transient response by a multiplier contained in the fifth integrator (Int _2V ). This part of the device is assigned to the second motor connection (V).

Int2W

sixth integrator. The sixth integrator according to the invention forms an associated third integrated sign signal (S _2W ) by integrating the third sign signal (Sig _w ). This device part is assigned to the third motor connection (W). The output of the sixth integrator is typically multiplied by -1 to output the third integrated sign signal (S _2W ). The value of the integration can be adjusted before output with a third constant factor (F _w ) to adjust the transient response by a multiplier contained in the sixth integrator (Int _2W ). This device part is assigned to the third motor connection (W).

IntCtrU

first integrator control signal for the first integrator (Int _1U ). The first integrator control signal is generated from the first sign signal (Sig _U ) by the first integrator control signal generation unit (X _U ) as a function of a first commutation interval signal (P _U ) and the first sign signal (Sig _U ). This device part is assigned to the first motor connection (U).

IntCtrV

second integrator control signal for the second integrator (Int _1V) . The second integrator control signal is generated from the second sign signal (Sig _V ) by the second integrator control signal generation unit (X _V ) as a function of a second commutation interval signal (P _V ) and the second sign signal (Sig _V ). This device part is assigned to the second motor connection (V).

IntCtrW

third integrator control signal for the third integrator (Int _1W ). The third integrator control signal is generated from the third sign signal (Sig _W ) by the third integrator control signal generation unit (X _W ) depending on a third commutation interval signal (P _W ) and the third sign signal (Sig _W ). This device part is assigned to the third motor connection (W).

M

exemplary BLDC motor

Φ1

first commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the first motor connection (U) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the third motor connection (W) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the second motor connection (V) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the second motor connection (V) in this commutation interval.

Φ2

second commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the first motor connection (U) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the second motor connection (V) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the third motor connection (W) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the third motor connection (W) in this commutation interval.

Φ3

third commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the third motor connection (W) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the second motor connection (W) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the first motor connection (U) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the first motor connection (U) in this commutation interval.

Φ4

fourth commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the third motor connection (W) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the first motor connection (U) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the second motor connection (V) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the second motor connection (V) in this commutation interval.

Φ5

fifth commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the second motor connection (V) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the first motor connection (U) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the third motor connection (W) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the third motor connection (W) in this commutation interval.

Φ6

sixth commutation interval. In this commutation interval, the upper switch of the half-bridge within the control circuit, which is connected to the second motor connection (V) on one side and the upper supply voltage on the other side, is closed. At the same time, in this commutation interval, the lower switch of the half-bridge within the control circuit, which is connected to the third motor connection (W) on one side and the lower supply voltage on the other side, is closed. In addition, both switches of the half-bridge within the control circuit that are connected to the first motor connection (U) are open. Therefore, the electromotive force (EMF) can be measured as a phase voltage at the first motor connection (U) in this commutation interval.

PU

first commutation interval signal. The first commutation interval signal signals to the first integrator control signal generation unit (X _W ), which generates the first integrator control signal (IntCtr _U ), in which commutation interval (Φ ₁ to Φ ₆ ) the system is located. The first commutation interval signal is typically generated by the control block (St) or another sub-device of the system according to the invention, for example on the basis of the commutation signals (A ₁ , A ₂ , A ₃ ). It can also be a bus of these commutation signals. The signal is assigned to the first motor connection (U).

PV

second commutation interval signal. The second commutation interval signal signals to the second integrator control signal generation unit (X _V ), which generates the second integrator control signal (IntCtr _V ), in which commutation interval (Φ ₁ to Φ ₆ ) the system is located. The second commutation interval signal is typically generated by the control block (St) or another sub-device of the system according to the invention, for example on the basis of the commutation signals (A ₁ , A ₂ , A ₃ ). It can also be a bus of these commutation signals. The signal is assigned to the second motor connection (V).

PW

third commutation interval signal. The third commutation interval signal signals to the third integrator control signal generation unit (X _W ), which generates the third integrator control signal (lntCtr _W ), in which commutation interval (Φ ₁ to Φ ₆ ) the system is located. The third commutation interval signal is typically generated by the control block (St) or another sub-device of the system according to the invention, for example on the basis of the commutation signals (A ₁ , A ₂ , A ₃ ). It can also be a bus of these commutation signals. The signal is assigned to the third motor connection (W).

S1U

first threshold signal. The first threshold signal is generated by integrating the corrected voltage signal (U _corr ) of the first motor connection (U) in the first integrator (Int _1U ). The signal is assigned to the first motor connection (U).

S1V

second threshold signal. The second threshold signal is generated by integrating the corrected voltage signal (V _corr ) of the second motor connection (V) in the second integrator Int _1V ). The signal is assigned to the second motor connection (V).

S1W

third threshold signal. The third threshold signal is generated by integrating the corrected voltage signal (W _corr ) of the third motor connection (W) in the third integrator (Int _1W ). The signal is assigned to the third motor connection (W).

S2U

first integrated sign signal. The first integrated sign signal according to the invention is generated by integrating the first sign signal (Sig _U ) of the first motor connection (U) in the fourth integrator (Int _2U ). The signal is assigned to the first motor connection (U).

S2V

second integrated sign signal. The second integrated sign signal according to the invention is generated by integrating the second sign signal (Sig _U ) of the second motor connection (V) in the fifth integrator (Int _2V ). The signal is assigned to the second motor connection (V).

S2W

third integrated sign signal. The third integrated sign signal according to the invention is generated by integrating the third sign signal (Sig _W ) of the third motor connection (W) in the sixth integrator (Int _2W ). The signal is assigned to the third motor connection (W).

S3U

first reload value for the new first preset value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation. The first reload value is loaded into the first sample and hold circuit (SaH _U ) during the next commutation. The signal is assigned to the first motor connection (U).

S3V

second reload value for the new second preset value (V _V ) according to the invention for the commutation of the second motor connection (V ) during the next commutation. The second reload value is loaded into the second sample and hold circuit (SaH _V ) during the next commutation. The signal is assigned to the second motor connection (V ).

S3W

third reload value for the new third preset value (V _W ) according to the invention for the commutation of the third motor connection (W) during the next commutation. The third reload value is loaded into the third sample and hold circuit (SaH _W ) during the next commutation. The signal is assigned to the third motor connection (W).

SaHU

first sample and hold circuit. During a commutation, the first sample and hold circuit loads the current first reload value (S _3U ) for the new inventive first default value (V _U ) for the commutation of the first motor connection (U) and outputs this as the first default value (V _U ) for the commutation of the first motor connection (U). The commutation time is determined by an edge of a first commutation signal (A ₁ ). The edge can be falling and/or rising depending on the implementation. The first commutation signal (A ₁ ) is a control signal for the control block (St). It is preferably the output signal (A ₁ ) of the fourth comparator (Cmp _2U ). This part of the device is assigned to the first motor connection (U).

SaHV

second sample and hold circuit. During commutation, the second sample and hold circuit loads the current second reload value (S _3V ) for the new inventive second preset value (V _V ) for the commutation of the second motor connection (V ) and outputs this as the second preset value (V _V ) for the commutation of the second motor connection (V ). The commutation time is determined by an edge of a second commutation signal (A ₂ ). The edge can be falling and/or rising depending on the implementation. The second commutation signal (A ₂ ) is a control signal for the control block (St). It is preferably the output signal (A ₂ ) of the fifth comparator (Cmp _2V ). This part of the device is assigned to the second motor connection (V).

SaHW

third sample and hold circuit. During a commutation, the third sample and hold circuit loads the current third reload value (S _3W ) for the new inventive third preset value (V _W ) for the commutation of the third motor connection (W) and outputs this as the third preset value (V _W ) for the commutation of the third motor connection (W). The commutation time is determined by an edge of a third commutation signal (A ₃ ). The edge can be falling and/or rising depending on the implementation. The third commutation signal (A ₃ ) is a control signal for the control block (St). It is preferably the output signal (A ₃ ) of the sixth comparator (Cmp _2W ). This part of the device is assigned to the third motor connection (W).

SgnU

first sign unit. The first sign unit according to the invention determines the sign of the corrected voltage signal (U _corr ) of the first motor connection (U). It outputs the first sign signal (Sig _U ). This device part is assigned to the first motor connection (U).

SgnV

second sign unit. The second sign unit according to the invention determines the sign of the corrected voltage signal (V _corr ) of the second motor connection (V). It outputs the second sign signal (Sig _V ). This device part is assigned to the second motor connection (V).

SgnW

third sign unit. The third sign unit according to the invention determines the sign of the corrected voltage signal (W _corr ) of the third motor connection (W). It outputs the third sign signal (Sig _w ). This device part is assigned to the third motor connection (W).

SigU

first sign signal. The first sign signal represents the sign of the corrected voltage signal (U _corr ) of the first motor connection (U). The signal is assigned to the first motor connection (U).

SigV

second sign signal. The second sign signal represents the sign of the corrected voltage signal (V _corr ) of the second motor connection (V). The signal is assigned to the second motor connection (V).

SigW

third sign signal. The third sign signal represents the sign of the corrected voltage signal (W _corr ) of the third motor connection (W). The signal is assigned to the third motor connection (U).

SdT

Marking the figure in question as state of the art

SpS

virtual star point signal. The virtual star point signal is preferably the sum of the first, second and third reduced terminal signals (U _r , V _r , W _r ) and is formed in the first summer (SU ₁ ). The signal is assigned to all motor connections (U, V, W).

SpT1

first voltage divider. The first voltage divider reduces the voltage at the first motor connection (U) by a factor of 1/3 to the reduced first terminal signal (U _r ). This part of the device is assigned to all motor connections (U, V, W).

SpT2

second voltage divider. The second voltage divider reduces the voltage at the second motor connection (U) by a factor of 1/3 to the reduced second terminal signal (V _r ). This part of the device is assigned to all motor connections (U, V, W).

SpT3

third voltage divider. The third voltage divider reduces the voltage at the third motor connection (W) by a factor of 1/3 to the reduced third terminal signal (W _r ). This part of the device is assigned to all motor connections (U, V, W).

SSt

System control This is typically a finite state machine as a sequence control and/or a microprocessor with memory. The system control typically comprises in particular one or more analog-to-digital converters and possibly further sample-and-hold circuits which generate the precharge value (V ₀ ) for the sample-and-hold circuits (SaH _U , SaH _V , SaH _W ). This precharge value (V ₀ ) can also be generated in the form of three separate precharge values (V _0U , V _0V , V _0W ) specifically for the respective branch (ZW1, ZW2, ZW3). In addition, the system control (SSt) evaluates the state of the respective inventive default value (V _U , V _V , V _W ). This can again be done, for example, by digital-to-analog conversion and evaluation of the digitized signal curve of the respective inventive default value (V _U , V _V , V _W ). If the respective inventive default value (V _U , V _V , V _W ) fluctuates between two or more than two engine revolutions by less than 25%, preferably less than 12%, preferably less than 6%, preferably less than 2%, preferably less than 1%, the system control (SSt) opens the respective switch (SW _U , SW _V , SW _W ). After the supply voltage is switched off, however, the system would lose the respective inventive default value (V _U , V _V , V _W ) and would have to carry out new parameterization the next time it is switched on. It is therefore sensible if the respective inventive default value (V _U , V _V , V _W ) is saved in a non-volatile, preferably digital memory, preferably within the system control (SSt) and is used as the respective assigned specific precharge value (V _0U , V _0V , V _0W ) when the system is restarted as a replacement for the general precharge value (V ₀ ). The non-volatile memory takes over the respective assigned pre-charge value according to the invention (V _U , V _V , V _W ) when the respective switch (SW _U , SW _V , SW _W ) is opened and can therefore also be able, for example in the case of a non-volatile memory, to store the respectively determined pre-charge value according to the invention (V _U , V _V , V _W ) as the respective specific pre-charge value (V _0U , V _0V , V _0W ) beyond the switching off of the supply. This part of the device is typically assigned to all motor connections (U, V, W).

St

Control block. The control block generates the signals for the three motor connections (U, V, W) from the commutation signals A ₁ , A ₂ , A ₃ . This control circuit for block commutation typically has three half bridges (not shown). A first half bridge is connected with its output to the first motor connection (U). A second half bridge is connected with its output to the second motor connection (V). A third half bridge is connected with its output to the third motor connection (W). Each of the half bridges typically has an upper switch that can connect the output of the relevant half bridge to an upper supply voltage and a lower switch that can connect the output of the relevant half bridge to a lower supply voltage. Simultaneous connection of the upper and lower supply voltage to the respective output of a half bridge is prevented by a locking circuit within the control circuit for block commutation. In addition, the control circuit for block commutation has a logic that can assume at least six states. These six states correspond to the six commutation intervals (Φ ₁ to Φ ₆ ). With a given edge of a commutation signal (A ₁ , A ₂ , A ₃ ), which can be falling and/or rising, the control circuit changes its state. This can lead to asynchronicity of the commutation signals (A ₁ , A ₂ , A ₃ ).

SU1

first summer. The first summer forms a virtual star point signal (SpS) from the first, second and third reduced terminal signals (U _r , V _r , W _r ). This part of the device is typically assigned to all motor connections (U, V, W).

SU2U

second summer for the first motor connection (U). The second summer for the first motor connection (U) subtracts the virtual star point signal (SpS) from the voltage signal of the first motor connection (U) and thereby forms the corrected voltage signal (U _korr ) of the first motor connection (U). This part of the device is assigned to the first motor connection (U).

SU2V

second summer for the second motor connection (V). The second summer for the second motor connection (V) subtracts the virtual star point signal (SpS) from the voltage signal of the second motor connection (V) and thereby forms the corrected voltage signal (V _corr ) of the second motor connection (V). This part of the device is assigned to the second motor connection (V).

SU2W

second summer for the third motor connection (W). The second summer for the third motor connection (V) subtracts the virtual star point signal (SpS) from the voltage signal of the third motor connection (W) and thereby forms the corrected voltage signal (W _corr ) of the third motor connection (W). This part of the device is assigned to the third motor connection (W).

SU3U

third summer for the first motor connection (U). The third summer for the first motor connection (U) adds the first integrated sign signal (S _2U ) and the first preset value (V _U ) according to the invention for the commutation of the first motor connection (U) to the first reload value (S _3U ) for the new first preset value (V _U ) according to the invention for the commutation of the first motor connection (U) during the next commutation. This device part is assigned to the first motor connection (U).

SU3V

third summer for the second motor connection (V). The third summer for the second motor connection (V) adds the second integrated sign signal (S _2V ) and the second preset value (V _V ) according to the invention for the commutation of the second motor connection (V) to the second reload value (S _3V ) for the new second preset value (V _V ) according to the invention for the commutation of the second motor connection (V) during the next commutation. This device part is assigned to the second motor connection (V).

SU3W

third summer for the third motor connection (W). The third summer for the third motor connection (W) adds the third integrated sign signal (S _2W ) and the third preset value (V _W ) according to the invention for the commutation of the third motor connection (W) to the third reload value (S _3W ) for the new third preset value (V _W ) according to the invention for the commutation of the third motor connection (W) at the next commutation. This device part is assigned to the third motor connection (W).

SWU

first switch. The first switch separates the first commutation signal (A ₁ ) from the trigger input of the first sample-and-hold circuit (SaH _U ). Preferably, it sets the trigger input of the first sample-and-hold circuit (SaH _U ) to a defined potential in such a way that it no longer accepts any further values depending on the first commutation signal (A ₁ ). This part of the device is assigned to the first motor connection (U).

SWV

second switch. The second switch separates the second commutation signal (A ₂ ) from the trigger input of the second sample-hold circuit (SaH _V ). Preferably, it sets the trigger input of the second sample-hold circuit (SaH _V ) to a defined potential in such a way that it no longer accepts any further values depending on the second commutation signal (A ₂ ). This part of the device is assigned to the second motor connection (V).

SWW

Third switch. The third switch separates the third commutation signal (A ₃ ) from the trigger input of the third sample-and-hold circuit (SaH _W ). Preferably, it sets the trigger input of the third sample-and-hold circuit (SaH _W ) to a defined potential in such a way that it no longer accepts any further values depending on the third commutation signal (A ₃ ). This part of the device is assigned to the third motor connection (W).

U

first motor connection of the exemplary BLDC motor

Ur

reduced first terminal signal. The voltage level is preferably 1/3 lower than the voltage at the first motor connection (U). The signal is assigned to the first motor connection (U).

Ukorr

corrected voltage signal (U _korr ) of the first motor connection (U). The corrected voltage signal (U _korr ) of the first motor connection (U) is generated in the associated second summer (SU _2U ) by subtracting the virtual star point signal (SpS) from the voltage signal of the first motor connection (U). The signal is assigned to the first motor connection (U).

U'korr

limited corrected voltage signal (U' _corr ) of the first motor connection (U). The signal is assigned to the first motor connection (U).

V

second motor connection of the exemplary BLDC motor

V0

Precharge value for the sample and hold circuits (SaH _U , SaH _V , SaH _W . This is the initialization value for the first, second and third preset values (V _U , V _V , V _W ). In order for the very first commutation to be successful, there must be an initial value for the first, second and third preset values (V _U , V _V , V _W ) to initialize the system, with which the respective commutation signal (A ₁ , A ₂ , A ₃ ) can be generated at the beginning as a start value for the control. This initial value can be set quite roughly and only ensures that the process can start at all. The value itself is not completely independent of the motor, but can be chosen so that it can be used unchanged for a very wide range of motors. The signal is typically assigned to all motor connections (U, V, W).

V0U

first precharge value. The signal is assigned to the first motor connection (U).

V0V

second precharge value. The signal is assigned to the second motor connection (V).

V0W

third precharge value. The signal is assigned to the third motor connection (W).

Vr

reduced second terminal signal. The voltage level is preferably 1/3 lower than the voltage at the second motor terminal (V). The signal is assigned to the second motor terminal (V).

VrefU

first default value for commutation experimentally optimized according to the state of the art. The signal is assigned to the first motor connection (U).

VrefV

second default value for commutation experimentally optimized according to the state of the art. The signal is assigned to the second motor connection (V).

VrefW

third default value for commutation experimentally optimized according to the state of the art. The signal is assigned to the third motor connection (W).

VU

determined first default value for the commutation of the first motor connection (U). The signal is assigned to the first motor connection (U).

VV

determined second default value for the commutation of the second motor connection (V). The signal is assigned to the second motor connection (V).

VW

determined third default value for the commutation of the third motor connection (W). The signal is assigned to the third motor connection (W).

Vkorr

corrected voltage signal (V _corr ) of the second motor connection (V). The corrected voltage signal (V _corr ) of the second motor connection (V) is generated in the associated second summer (SU _2V ) by subtracting the virtual star point signal (SpS) from the voltage signal of the second motor connection (V). The signal is assigned to the second motor connection (V).

V'korr

limited corrected voltage signal (V' _corr ) of the second motor connection (V). The signal is assigned to the second motor connection (V).

W

third motor connection of the exemplary BLDC motor

Wr

reduced third terminal signal. The voltage level is preferably 1/3 lower than the voltage at the third motor terminal (W). The signal is assigned to the third motor terminal (W).

Wkorr

corrected voltage signal (W _korr ) of the third motor connection (W). The corrected voltage signal (W _korr ) of the third motor connection (W) is generated in the associated second summer (SU _2W ) by subtracting the virtual star point signal (SpS) from the voltage signal of the third motor connection (W). The signal is assigned to the third motor connection (W).

W'korr

limited corrected voltage signal (W' _corr ) of the third motor connection (W). The signal is assigned to the third motor connection (W).

XU

first integrator control signal generation unit. The first integrator control signal generation unit generates the first integrator control signal (IntCtr _U ) on the basis of the first commutation interval signal (P _U ) and the first sign signal (Sig _U ). This device part is assigned to the first motor connection (U).

XV

second integrator control signal generation unit. The second integrator control signal generation unit generates the second integrator control signal (IntCtr _V ) on the basis of the second commutation interval signal (P _V ) and the second sign signal (Sig _V ). This device part is assigned to the second motor connection (V).

XW

third integrator control signal generation unit. The third integrator control signal generation unit generates the third integrator control signal (IntCtr _W ) on the basis of the third commutation interval signal (P _W ) and the third sign signal (Sig _W ). This device part is assigned to the third motor connection (W).

ZW1

first branch within the EMF evaluation (EMKA) for generating the first commutation signal (A ₁ ) from the EMF at the first motor connection (U) during the third commutation interval (Φ ₃ ) and during the sixth commutation interval (Φ ₆ ). This device part is assigned to the first motor connection (U).

ZW2

second branch within the EMF evaluation (EMKA) for generating the second commutation signal (A ₂ ) from the EMF at the second motor connection (V) during the first commutation interval (Φ ₁ ) and during the fourth commutation interval (Φ ₄ ). This device part is assigned to the second motor connection (V).

ZW3

third branch within the EMF evaluation (EMKA) for generating the third commutation signal (A ₃ ) from the EMF at the third motor connection (W) during the second commutation interval (Φ ₂ ) and during the fifth commutation interval (Φ ₅ ). This device part is assigned to the third motor connection (W).

Claims (11)

Method for determining the first default value (V _U ) to be determined for the regulation of the commutation time for the control of the stator coils of a BLDC motor via at least one first motor connection (U), characterized by the steps of a. continuously or continuously scanning determining the sign of an assigned, corrected first voltage signal (U korrU ) derived from the EMF at the first motor connection (U) in a commutation interval (Φ ₃ , Φ ₆ ) in which this first motor connection is not supplied with current by a control block (St), by means of a first sign unit ( _{Sgn U} ) assigned to the first motor connection (U) to generate an assigned first sign signal (Sig _U ), b. integration and/or filtering of the relevant assigned first sign signal (Sig _U ) by a subsequent fourth integrator (Int _2U ) to generate an assigned first integrated sign signal (S _2U ), c. optionally multiplying the associated first integrated sign signal (S _2U ) before its output by the fourth integrator (Int _2U ) by a first constant factor (F _U ), in particular by one or more sub-devices of the fourth integrator (Int _2U ), d. continuous and/or sampling-summing integration and/or filtering of an associated, first corrected voltage signal (U _korrU ) derived from the EMF at the first motor connection (U) in a commutation interval (Φ ₃ , Φ ₆ ) in which this first motor connection is not supplied with current by the control block (St), by a subsequent first integrator (Int _1U ) to generate an associated first threshold signal (S _1U ), e. Comparing the assigned first threshold signal (S _1U ) with a determined first preset value (V _U ) by means of an assigned fourth additional comparator (CMP _2U ), f. Forming an assigned first commutation signal (A ₁ ) as a function of the comparison result of the assigned fourth additional comparator (CMP _2U ), g. Changing the commutation time of an assigned output of a control block (St) which is connected to the assigned first motor connection (U) as a function of the assigned first commutation signal (A ₁ ), h. Adding the assigned determined first preset value (V _U ) to the assigned first integrated sign signal (S _2U ) by means of an assigned second summer (SU _2U ) for the first motor connection (U), i. Formation of an assigned first recharge value (S _3U ) as a function of the result of the addition of the assigned determined first default value (V _U ) with the assigned first integrated sign signal (S _2U ) by an assigned second summer (SU _2U ) for the first motor connection (U), j. Storage of the assigned first recharge value (S _3U ) in an assigned memory for this value, in particular an assigned first sample and hold circuit (SaH _U ), at least temporarily as a function of the assigned first commutation signal (A ₁ ), k. Generation of the assigned first default value (V _U ) as a function of the current storage value of the assigned first recharge value (S _3U ) in the assigned memory for the assigned first recharge value (S _3U ), in particular in the assigned first sample and hold circuit (SaH _U ). Procedure according to Claim 1 , comprising the steps of a. connecting the assigned first commutation signal (A ₁ ), in particular by means of an assigned first switch (SW _U ), to an assigned memory for this value, in particular an assigned first sample and hold circuit (SaH _U ), in such a way that the storage of the assigned first reload value (S _3U ) as an assigned first default value (V _U ) in the assigned memory for this value, in particular in the assigned first sample and hold circuit (SaH _U ), takes place as a function of the assigned first commutation signal (A ₁ ), b. storing the assigned first default value (V _U ) in an assigned memory for this assigned first default value (V _U ), in particular in a non-volatile memory in a system controller (SSt), c. Separating the associated first commutation signal (A ₁ ), in particular by opening an associated first switch (SW _U ), from the associated memory for the associated first recharge value (S _3U ) in such a way that the stored associated first preset value (V _U ) is stored on the basis of the associated first recharge value (S _3U ) or the associated first precharge value (V _0U ) or another precharge value (V ₀ ) in this associated memory during this separation is NOT dependent on the associated first commutation signal (A ₁ ), Method according to one or more of the preceding claims, comprising the steps of a. separating the associated first commutation signal (A ₁ ), in particular by opening an associated first switch (SW _U ), from the associated memory for the associated first recharge value (S _3U ) in such a way that the storage of the stored associated first default value (V _U ) on the basis of the associated first recharge value (S _3U , S _3V , S _3W ) or the associated first precharge value (V _0U , V _0V , V _0W ) or another precharge value (V ₀ ) in this associated memory during this separation does NOT take place as a function of the associated first commutation signal (A ₁ ), b. Outputting the assigned first default value (V _U ) previously stored in an assigned memory, in particular a non-volatile memory in a system controller (SSt), as a new assigned first precharge value (V _0U ) for the following commutation intervals (Φ ₁ to Φ ₆ ), c. Storing the new assigned first precharge value (V _0U ) instead of the assigned first recharge value (S _3U ) in the assigned memory for the assigned first recharge value (S _3U ), in particular in the assigned first sample and hold circuit (SaH _U ), for at least one commutation interval (Φ ₁ to Φ ₆ ), d. subsequently connecting the associated first commutation signal (A ₁ ), in particular by means of the associated first switch (SW _U ), in such a way that the storage of the associated first recharge value (S _3U ) in an associated memory for this value, in particular an associated first sample-and-hold circuit (SaH _U ), takes place as a function of the associated first commutation signal (A ₁ ). Method according to one or more of the preceding claims, comprising the steps of a. separating the assigned first commutation signal (A ₁ ), in particular by opening an associated first switch (SW _U ), from the associated memory for the associated first recharge value (S _3U ) in such a way that the storage of the stored assigned first default value (V _U ) on the basis of the associated first recharge value (S _3U ) or the associated first precharge value (V _0U ) or another precharge value (V ₀ ) in this associated memory during this separation does NOT occur as a function of the associated first commutation signal (A ₁ ), b. outputting the default value (V ₀ ) previously stored or otherwise made available in an associated non-volatile memory, in particular in a system controller (SSt), as the associated first precharge value (V _0U ), c. Storing the associated first precharge value (V _0U ) instead of the associated first recharge value (S _3U ) in the associated memory for the associated first recharge value (S _3U ), in particular in the associated first sample and hold circuit (SaH _U ), for at least one commutation interval (Φ ₁ to Φ ₆ ), d. Connecting the associated first commutation signal (A ₁ ), in particular by means of the associated first switch (SW _U ), in such a way that the associated first recharge value (S _3U ) is stored in an associated memory for this value, in particular an associated first sample and hold circuit (SaH _U ), as a function of the associated first commutation signal (A ₁ ). Method according to one or more of the preceding claims, additionally characterized in that a. the integration and/or filtering of an assigned, corrected voltage signal (U _korrU ) derived from the EMF at the motor connection (U) in a commutation interval (Φ ₃ , Φ ₆ ) in which this motor connection (U) is not supplied with current by the control block (St) is carried out by a subsequent first integrator (Int _1U ) to generate an assigned first threshold value signal (S _1U) in such a way that only one polarity of the respective corrected voltage signal (U _korrU ) influences the value of the respectively assigned first threshold value signal (S _1U ). Device for determining at least one first preset value (V _U ) to be determined and for controlling the commutation time for controlling the stator coils of a BLDC motor, characterized by a. a first sign unit (Sgn _U ) assigned to a first motor connection (U) which, in order to generate an assigned first sign signal (Sig _U ) during a commutation interval (Φ ₃ , Φ ₆ ) in which this first motor connection (U) is not supplied with current by a control block (St), continuously or continuously sampling determines the sign of an assigned, corrected voltage signal (U _korrU ) of the first motor connection (U) derived from the EMF at the first motor connection (U), and b. an assigned fourth integrator (Int _2U ) for continuous and/or sampling-summing integration. ration and/or filtering of the relevant assigned first sign signal (Sig _U ) to generate an assigned first integrated sign signal (S _2U ), and c. an assigned subsequent first integrator (Int _1U ) for the continuous and/or sampling-summing integration and/or filtering of an assigned, corrected voltage signal (U korrU ) of the first motor connection (U) derived from the EMF at the first motor connection (U) in a commutation interval (Φ ₃ , Φ ₆ ) in which this motor connection is not supplied with current by the control block ( _St ), to generate an assigned first threshold value signal (S _1U ), and d. an assigned fourth comparator (CMP _2U ) for comparing the assigned threshold value signal (S _1U ) with a determined first default value (V _U ), and e. a device for forming an associated first commutation signal (A ₁ ) depending on the comparison result of the associated fourth comparator (CMP _2U ), wherein the commutation time of an associated output of a control block (St) which is connected to the associated first motor connection (U) depends on the associated first commutation signal (A ₁ ), and f. an associated second summer (SU _2U ) for adding the associated determined first default value (V _U ) to the associated first integrated sign signal (S _2U ) and g. a device for forming an associated first recharge value (S _3U ) depending on the result of the addition of the associated determined first default value (V _U ) to the associated first integrated sign signal (S _2U ) by an associated second summer (SU _2U ) for the first motor connection (U) and h. an associated memory for this value, in particular an associated first sample-and-hold circuit (SaH _U ), for at least temporarily storing the associated first recharge value (S _3U ) as a function of the associated first commutation signal (A ₁ ) and i. a sub-device for generating the associated first default value (V _U ) as a function of the current storage value of the associated first recharge value (S _3U ) in the associated memory for the associated first recharge value (S _3U ), in particular in the associated first sample-and-hold circuit (SaH _U ). Device according to Claim 6 , characterized additionally by a. an associated first switch (SW _U ) for connecting the associated first commutation signal (A ₁ ) in such a way that the storage of the associated first recharge value (S _3U ) in an associated memory for this value, in particular an associated first sample and hold circuit (SaH _U ), takes place as a function of the associated first commutation signal (A ₁ ) when the first switch (SW _U ) is in a first state, in particular closed, and that the storage of the associated first recharge value (S _3U ) in an associated memory for this value, in particular an associated first sample and hold circuit (SaH _U ), does NOT take place as a function of the associated first commutation signal (A ₁ ) when the first switch (SW _U ) is in a second state, in particular open. Device according to one or more of the Claims 6 or 7 , characterized additionally by a. an associated, in particular non-volatile memory for the associated first default value (V _U ), which can in particular be a memory in a system controller (SSt). Device according to one or more of the Claims 6 until 8th , characterized additionally by a. that in the assigned memory for the assigned first recharge value (S _3U ) at least one further value can be stored as a substitute in addition to the assigned first recharge value (S _3U ), wherein this further value can be an assigned first precharge value (V _0U ) and/or another precharge value (V ₀ ). Device according to one or more of the Claims 6 until 9 characterized in that a. the output of the associated fourth comparator (CMP _2U ) has a hysteresis. Device according to one or more of the Claims 6 until 10 , characterized in that a. the device has a sub-device (X _U , B _U ) which ensures that the continuous and/or sampling-summing integration and/or the filtering of an associated, corrected voltage signal (U korrU ) derived from the EMF at the first motor connection (U) in a commutation interval (Φ ₃ , Φ ₆ ) in which this first motor _connection (U) is not supplied with current by the control block (St) by a subsequent first integrator (Int _1U ) for generating an associated first Threshold signal (S _1U ) is carried out in such a way that only one polarity of the respective corrected voltage signal (U _korrU ) influences the value of the respectively assigned first threshold signal (S _1U ).

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