Modulation mode switching architecture for motor

Abstract

The present invention relates to the field of (digitally controlled) electric motors, (digital) control systems, (electric) motor-based systems, including those (digital) control systems, and methods relating thereto. The present invention addresses the complexity of dynamic switching between two or more different modulation algorithms, such as SVPWM (Space Vector Pulse Width Modulation), SPWM (Sinusoidal Pulse Width Modulation), THIPWM (Third Harmonic Pulse Width Modulation), DPWM (Discontinuous Pulse Width Modulation), OPP (Optimized Pulse Pattern).

Description

Technical Field

[0001] This invention relates to the field of (digitally controlled) electric motors, (digital) control systems, (electric) motor-based systems (including those (digital) control systems), and related methods. Background Technology

[0002] This invention applies to the context of digital control algorithms for motors, and more specifically, to the control of synchronous motors via inverter power stages.

[0003] This invention solves the complexity of dynamically switching between two or more different modulation algorithms, such as SVPWM (Space Vector Pulse Width Modulation), SPWM (Sinusoidal Pulse Width Modulation), THIPWM (Third Harmonic Pulse Width Modulation), DPWM (Discontinuous Pulse Width Modulation), and OPP (Optimized Pulse Pattern).

[0004] In this context, "modulation" is a digital function that allows the generation of the optimal sinusoidal waveform for the motor coils via the multiphase inverter module, as shown in Figure 01.

[0005] Depending on the motor setpoint (torque / speed), it has been shown that some modulations are more efficient than others; for example, SVPWM modulation is more efficient at low speeds. Therefore, the ability to dynamically switch from one modulation to another is key to achieving better efficiency at all motor operating points.

[0006] In the aforementioned motor control architecture, a typical modulation architecture includes a repetitive real-time loop executed at a specific rate (referred to as the "sampling rate").

[0007] The different steps in this cycle may vary slightly depending on the modulation mode. However, as Figure 2 As shown, the following global sequence applies to all modes:

[0008] •(0201): Field-oriented control (FOC) function. This stage is common to any modulation algorithm. Its role is to provide information about the current angular position of the motor and the difference between the actual operating point and the target operating point.

[0009] •(0202): Modulation algorithm that interprets information from the FOC stage and calculates the necessary power stage switching digital commands applied to the gate of the power stage transistor.

[0010] •(0203): Motor phase current measurement stage. This is typically a set of analog-to-digital converters (ADCs) that can provide accurate information about the current motor state.

[0011] •(0204): Clark and Parker transformation function, used to convert three-dimensional motor phase information into two-dimensional Id / Iq information.

[0012] •(0205): Adjustment of Id / Iq information. This is usually done through a proportional / integral digital filtering stage.

[0013] like Figure 2 As illustrated in the diagram, a (digital) control system requires two basic functions, particularly regulation and modulation, as well as other functions such as phase current measurement (estimation) from the input.

[0014] The optimal control requirements of a (electric) motor are based on the operating conditions of the (electronic) motor (e.g., defined as the required speed and torque) to select an appropriate modulation method.

[0015] While a straightforward implementation would be to provide a set of parallel devices, implementing the modulation method (such as...) Figure 3 (as shown), but this creates compatibility with regulators, and another straightforward solution to this (such as...) Figure 4 (As shown) is a method for providing a set of parallel devices and implementing their implementation.

[0016] Such methods can lead to significant hardware overhead.

[0017] As mentioned in the introduction, the efficiency of a given modulation algorithm depends on the actual operating point of the electric motor (torque and speed). The goal is to provide maximum efficiency under all possible operating conditions of the electric vehicle. Therefore, there is a clear benefit to being able to dynamically switch from one modulation to another depending on the motor state. Essentially, this principle can be summarized as shown in Figure 03, which illustrates the multi-modulation principle with an ideal visual representation.

[0018] • Additional logic is required. This logic is responsible for selecting the optimal modulation algorithm based on the actual motor operating conditions.

[0019] •(0302): A set of modulation algorithms is available.

[0020] • (0303): The output multiplexer is controlled by the mode selection controller (0301) to apply the selected one to the output power stage transistor.

[0021] This "ideal" concept raises several questions (as presented below) that must be addressed in order to establish a realistic system.

[0022] Different modulation algorithms do not share the exact same sampling rate. For example, SVPWM modulation operates on a fixed frequency loop, while OPP modulation does not operate on a fixed frequency, but rather on an electrical frequency proportional to the motor speed.

[0023] The problem is that the adjustment phase (0205) is a digital filter whose parameters must be aligned with the current sampling rate to obtain an appropriate frequency response. In other words, changing the sampling rate without correspondingly changing the regulator parameters will result in inappropriate motor control.

[0024] When dealing with the inverter power stage presented in Figure (01), an important condition to be observed is the obligation to prevent any situation in which the “upper” and “lower” transistors can “pass” simultaneously (which is obviously a short circuit).

[0025] Ideally, this means that the "upper" transistor and the "lower" transistor are either one of the following or the other:

[0026] • Systematically control to the opposite state

[0027] • Both are “disconnected” (a state we call a “free wheel)”.

[0028] If all modulation algorithms meet those conditions, then we can imagine that switching from one to another will not cause a short circuit.

[0029] The problem is that, in practice, due to the propagation delay between the digital control and the transistor gate, simultaneous transitions at the control output can cause a slight misalignment at the transistor gate. Therefore, we can have transients where short-circuit conditions occur.

[0030] This is a well-known problem, and we can assume that each modulation algorithm embeds an appropriate "dead time" insertion to prevent unsafe situations.

[0031] However, when switching between modulations, the same problem may occur due to modulation asynchrony.

[0032] In addition, such as Figure 4 The existing technology solutions are shown in the figure.

[0033] •(0401): There exists a regulator associated with each modulation algorithm. This allows the regulator parameters to be aligned with the specific sampling rate of each modulator.

[0034] •(0402): In this case, each modulator does not provide any dead time insertion function.

[0035] This existing technological solution has a complexity problem because

[0036] First, having multiple regulators is an obvious waste of resources, as they are essentially the same (except for the parameters), and only one of them is used at any given time.

[0037] Furthermore, the regulator output must be synchronized during mode switching to ensure a smooth transition. Since each modulation has a different sampling rate, this synchronization is not always apparent and often results in complex sequences. Purpose of the invention

[0038] The purpose of this invention is to enable the smooth selection of appropriate modulation methods according to the operating conditions of (electronic) motors, while avoiding significant hardware overhead. In particular, the technical considerations made here enable the implementation of more modulation methods. Summary of the Invention

[0039] In a first aspect of the invention, a (digital) control system for regulating and modulating a (digitally controlled) motor includes: (1) a regulating device (0501); (2) a plurality of modulation devices (0504); (3) a selector (0510) for selecting one of the output signals provided by the modulation devices; and (4) a controller (0503) for (a) manipulating the selection of the selector and (b) providing the regulating parameter (0502) to the regulating device.

[0040] exist Figure 5 , Figure 6 , Figure 7 or Figure 8 In the illustrated embodiment, there is essentially a single modulation device compared to multiple modulation devices, or the phases are different. An intentional selection is made to make fewer modulation devices than modulation devices. This requires the modulation devices to use modulation parameters so that a modulation method aligned with the modulation method is used.

[0041] exist Figure 13 In an alternative embodiment, a (digital) control system for regulating and modulating a (digitally controlled) motor includes: (1) one or more regulating devices; (2) a plurality of modulation devices dedicated to one of the regulating devices, all receiving input signals from their associated regulating device; (3) a selector for selecting one of the output signals provided by the modulation device (and thereby selecting that modulation device as the active modulation device); and (4) a controller for (a) manipulating the selection of the selector, and (b) providing the regulation parameters to the associated regulating device among the regulating devices. Although a choice is made here to use more than one regulator, an intentional choice is still made to have fewer regulating devices than modulation devices.

[0042] In embodiments of the invention, at least two modulation devices are present, preferably three modulation devices. In an embodiment of the invention with two modulation devices, at most one regulator with programmable parameters is present. In an embodiment of the invention with three modulation devices, one or more regulators may be present, wherein the regulator serving the two modulation devices should have programmable parameters.

[0043] This invention is in Figure 5 and Figure 6 An embodiment using a multiplexer is shown. Note that in this embodiment, some modulators in the modulator are effectively stopped because they are no longer being fed data.

[0044] However, Figure 7 and Figure 8 An embodiment utilizing direct connections is shown. Note that in this embodiment, since all modulators in the modulator are fed data and can operate at the maximum sampling rate frequency, they can continue to operate in parallel. Due to operation at reasonable frequencies, the power consumption overhead in this particular solution is negligible. Instead, the fact that they operate continuously in parallel is a better guarantee of switching from one modulation to another. Triggering or restarting them some time before switching could, on the contrary, cause the control loop to diverge during switching. This is a major advantage of this embodiment. Switching can be performed at any time. This is in contrast to the prior art where the switching time to another modulation is constrained. Switching to another modulation cannot be performed at any time. When dead time is not required, (or worse) when all transistor circuits are off (which results in the motor being set to freewheeling), switching to another modulation is forced. This generates latency in response time, fluctuations in control, and even worse… control may diverge. Nevertheless, in embodiments of the invention, it is beneficial to monitor gate conditions because the controller can account for this because it may not need to trigger its own dead time and / or freewheeling (open-circuit) measures.

[0045] Embodiments utilizing more regulating devices (but fewer regulating devices than modulating devices) can also be achieved through direct connections between one or more of the regulating devices and / or direct connections between the system input and one or more of the regulating devices.

[0046] When switching from one modulation mode to another, the so-called dead time measures taken during normal modulation may be insufficient because the modulations are out of sync when switching between them.

[0047] Therefore, in embodiments of the invention, in addition to a suitable switching method, the control system further includes a dead-time insertion device that receives the output of the selector and inserts a dead-time period when activated. A further feature of the system is that the controller is further adapted to activate the dead-time insertion device. Specifically, while the dead-time insertion device can act on the control of the controller, it can also act autonomously or under the control of signals generated elsewhere in the system. In alternative embodiments of the invention, the presence of a dead-time insertion circuit not (directly) linked to the controller is provided.

[0048] It is worth noting that this type of dead-time insertion is typically applied to each branch of the inverter. An alternative is discussed below (where all branches are open-circuited).

[0049] In the embodiment of the present invention utilizing a freewheeling control device (freewheeling is also referred to as open circuit), the following observations can be made:

[0050] Currently, no additional common dead-time insertion block is available, but in this invention, the provided modulation devices may include their own dead-time insertion functionality.

[0051] In this invention, a common dead-time insertion block or function can be introduced (e.g., as part of the freewheeling control device discussed further) based on the minimum dead time required by all modulators, and instead adapted (subtracted from) the dead-time insertion function of each modulator. The same considerations can be made for embodiments utilizing a common dead-time insertion.

[0052] When switching from one modulation mode to another, the so-called dead time measures taken during normal modulation may be insufficient because the modulations are out of sync when switching between them.

[0053] In embodiments of the present invention, therefore, in addition to a suitable switching method, the control system further includes: (5) a freewheeling control device (0505) receiving the output of the selector, wherein the controller is further adapted to (c) activate the freewheeling control device and / or apply a dead time to the branch of the inverter, preferably when a change in transistor state caused by a modulation change is required.

[0054] The modulation switching sequence may depend on an additional stage between the regulating device and the multiplexer and / or the modulator, and therefore in embodiments of the invention, the control system further includes: (6) a pipeline stage (0506) between the regulating device and the multiplexer ( Figure 5 , Figure 6 ) and / or the regulating device and the modulator ( Figure 7 , Figure 8 )between.

[0055] In a second aspect of the invention, a method for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode to a second mode, the modes differing in the modulation scheme or regulation parameters used, or both, the method being implemented by a controller of the first aspect of the invention, the method comprising the steps of: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) (a) changing the parameters of the regulation device to align with the modulation device of the second mode, and (b) starting sampling according to the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period; (3) selecting the output signal of the modulation device of the second mode; and (4) deactivating the freewheeling overcurrent control device simultaneously with (3) or after (3). A similar method can be applied to dead-time insertion or dead-time protection methods, which introduce dead time for each branch only when a change in transistor state caused by a modulation change is required.

[0056] It is worth noting that two switching methods can be used: synchronous switching and asynchronous switching. Synchronous switching requires that the sampling rates of the modes to be switched to be multiples of each other. Depending on the control context, one of these methods can be chosen. Furthermore, it can be observed (e.g., if consistency no longer occurs within a anticipated time period) that the sampling rate condition is no longer met, or in other words, the hardware is no longer able to operate under this condition, and thus a switch from the synchronous method to the other method can be made.

[0057] When a hardware programmable unit is selected to implement a controller, a portion of the hardware programmable device can be reconfigured for such purposes.

[0058] The switching method has been discussed in the context of the continuous streaming embodiment, but the same considerations can be made for the dead time insertion embodiment. Attached Figure Description

[0059] Figure 1 The context of the invention and the location of the invented (digital) control system therein are provided.

[0060] Figure 2 The diagram illustrates the function of a (digital) control system.

[0061] Figure 3 The figure illustrates a prior art method utilizing multiple modulation devices and a fixed adjustment device.

[0062] Figure 4 The figure illustrates a further prior art method utilizing multiple modulation devices and multiple adjustment devices (both in equal amounts).

[0063] Figure 5 The present invention illustrates a (digital) control system utilizing unequal amounts of regulators (one in this case) and modulation devices (three in this case) as well as multiplexers.

[0064] Figure 6 The (digital) control system of the present invention is shown, utilizing unequal amounts of regulators (one in this case) and modulation devices (three in this case), as well as multiplexers and freewheeling or open-circuit blocks. Alternatively, dead-time insertion blocks may also be used here.

[0065] Figure 7 The (digital) control system of the present invention is shown, which utilizes unequal amounts of regulators (one in this case) and modulation devices (three in this case), as well as direct connections.

[0066] Figure 8 The (digital) control system of the present invention is illustrated, utilizing unequal amounts of regulators (one in this case) and modulation devices (three in this case), as well as direct connections and dead-time insertion blocks. Alternatively, freewheeling or open-circuit blocks may also be used here.

[0067] Figure 9 and Figure 10 The figure illustrates a possible switching method that can be used in conjunction with the (digital) control signals of the present invention in a freewheeling embodiment.

[0068] Figure 11 and Figure 12 The figure illustrates a possible switching method that can be used in conjunction with the (digital) control signals of the present invention for dead-time embodiments.

[0069] Figure 13 An embodiment of an alternative demultiplexer for the (digital) control system of the present invention is shown, utilizing unequal amounts of regulators (two in this case) and modulation devices (three in this case) that can be combined with freewheeling or open-circuit blocks and / or dead-time insert blocks. A direct connection method is also possible. Detailed Implementation

[0070] This invention relates to a (digital) control system for regulating and modulating (digitally controlled) electric motors, and to systems based on (electric) motors (such as...). Figure 1The following are listed in the abstract: (1) an electric motor (0103); (2) an electric motor power control device (0102) provided for controlling the electric motor; (3) a digital control system (0101) as described in the abstract, adapted to provide control signals to the electric motor power control device; and (4) an electric power storage device (0105) provided for supplying power to the electric motor power control device, wherein the electric motor power control device includes a plurality of switches (0106) connected in pairs in series. As shown, the digital control system provides control signals, which are essentially closing or opening switches, and the control signals are determined by adjustment and modulation methods. Note that the control system receives input signals (0110) obtained from measurements captured from the motor.

[0071] One or more regulating devices typically perform low-pass function, or more specifically, proportional / integral control.

[0072] The modulator performs digital functions, which allows the generation of (optimal) sine waves for the motor coils via the multiphase inverter module. More specifically, based on information from the FOC stage, it calculates the necessary power stage switching digital commands applied to the power stage transistor gates.

[0073] An embodiment of the invention's architecture is shown in Figure 05, and illustrates...

[0074] •(0501): The regulator stage is common to all modulation algorithms.

[0075] •(0502): This regulator receives regulation parameters from the modulation selection logic.

[0076] •(0503): This module is responsible for selecting the currently applicable modulation and managing the modulation transition sequence according to the following chapters.

[0077] •(0504): N modulation algorithms. Each of them depends on a common regulator.

[0078] An embodiment of the invention's architecture is shown in Figure 06, and further illustrates...

[0079] •(0505): The additional overcurrent control logic is responsible for inserting the "continuation" period under the control of (0503).

[0080] An embodiment of the invention's architecture is shown in Figure 07, and further illustrates...

[0081] •(0505): The additional overclocking logic is responsible for “dead time protection” under the control of (0503).

[0082] For these embodiments

[0083] •(0506): The modulation switching sequence may require at least one stage of a digital pipeline operating at the sampling rate to be inserted between conditioning and modulation.

[0084] Figure 7 and Figure 8 Alternatives using direct connections and / or dead-zone insertion blocks are shown.

[0085] As previously indicated, the direct connection method can be combined with the continuous flow embodiment.

[0086] Figure 13 An alternative is shown—featuring two regulator stages (0701), three modulation modules (0704), intermediate selection and pipeline stages (0706, 0720), and a further selection stage (0705). This alternative may also include a freewheeling stage.

[0087] In general, a (digital) control system for regulating and modulating a (digitally controlled) motor is provided, comprising: (1) a regulating device (0501) adapted to receive a regulating parameter (0502) to be aligned with the sampling rate of an active modulating device; (2) a plurality of modulating devices (0504), each having a different sampling rate, all receiving signals from the regulating device; (3) a selector (0510) for selecting one of the output signals provided by the modulating device (and thereby selecting the modulating device as the active modulating device); and (4) a controller (0503) for (a) manipulating the selection of the selector (and thereby implicitly selecting the modulating device), and (b) providing the regulating parameter (0502) to the regulating device.

[0088] The (digital) control system may further include: one or more additional regulating devices, each of which is provided with its dedicated modulation device (inputting a signal to its associated regulating device); the selector, capable of also selecting one of the output signals for those dedicated modulation devices; and a multiplexer for directing system input signals to any of the regulating devices, or alternatively, for regulating and modulating a (digitally controlled) motor, comprising: (1) one or more regulating devices adapted to receive regulating parameters aligned with the sampling rate of the active modulation device; (2) a plurality of modulation devices, each having a different sampling rate, the modulation devices being dedicated to one of the regulating devices and all inputting signals from their associated regulating devices; (3) a selector for selecting one of the output signals provided by the modulation device (and thereby selecting that modulation device as the active modulation device); and (4) a controller for (a) manipulating the selection of the selector, and (b) providing the regulating parameters to the regulating device.

[0089] The (digital) control system may include (5) a freewheeling overcurrent control device (0505), which receives the output of the selector and, when activated, inserts a freewheeling period (meaning all switches in the relevant (electric) motor power control device are off), a further feature of which is that the controller is further adapted to (c) activate the freewheeling overcurrent control device (via signal (0530)). Alternatively, a dead-time insertion block is provided. The (digital) control system may then include (5) a dead-time insertion and / or protection device (505), a further feature of which is that the controller is further adapted to (c) activate the dead-time protection device (503) (via signal (0530)).

[0090] The (digital) control system may include (6) a pipeline stage (0506) located between the regulating device and the multiplexer (or, in some cases, a modulator) for temporarily storing the regulator output.

[0091] This invention requires switching sequences. Two main embodiments of such sequences are represented as synchronous switching sequences; and asynchronous switching sequences are now described.

[0092] Synchronous switching sequence

[0093] In most cases, the sampling rates of different modulation algorithms are multiples of each other. If we take this as an assumption, switching sequences becomes much easier.

[0094] Figure 11 The sequence is explained in the context of either a continuous current or an open circuit method, and the following steps are shown:

[0095] 1) Before the switching, the power transistor is controlled by modulation "A". During this period, the motor current phase is sampled at the sampling rate of modulation "A".

[0096] 2) Finally, the mode selection control determines the change in modulation algorithm (from modulation "A" to modulation "B") (time T0).

[0097] 3) It waits for the sampling times of modulation "A" and "B" to occur simultaneously again. This is inevitable because both are multiples of each other (time T2).

[0098] 4) Then, it modifies the regulator parameters to align them with the sampling rate of modulation "B". This modification should only be effective at the sampling time of the next motor phase. Therefore, at this point, the output of the regulator pipeline stage (0506) is still being used to modulate "A".

[0099] 5) Force freewheeling state on the power gates to prevent dead-time violations at modulation switching times. This action must be performed before effective modulation switching.

[0100] 6) Starting from time T2, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0101] 7) At the next motor phase sampling time (time T3), the regulator receives new data aligned with the modulation “B” sampling rate, so the modulation algorithm can now be safely switched to modulation “B”.

[0102] 8) After a sufficient dead time period, the resume execution state is released (time T4).

[0103] 9) Now, the transistor is completely controlled by the modulation "B".

[0104] Figure 9 The sequence for the dead-time protection method is explained, and the following steps are shown:

[0105] 1) Before the switching, the power transistor is controlled by modulation "A". During this period, the motor current phase is sampled at the sampling rate of modulation "A".

[0106] 2) Finally, the mode selection control determines the change in modulation algorithm (from modulation "A" to modulation "B") (time T0).

[0107] 3) It waits for the sampling times of modulation "A" and "B" to occur simultaneously again. This is inevitable because both are multiples of each other (time T2).

[0108] 4) Then, it modifies the regulator parameters to align them with the sampling rate of modulation "B". This modification should only be effective at the sampling time of the next motor phase. Therefore, at this point, the output of the regulator pipeline stage (0506) is still being used to modulate "A".

[0109] 5) If a change in transistor state is required due to modulation change, the power gate is forced into a dead state to prevent violation of the dead time at the modulation switching time.

[0110] 6) This action is performed simultaneously with the modulation switching that utilizes the dead-time protection function.

[0111] 7) Starting from time T2, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0112] 8) At the next motor phase sampling time (time T3), the regulator receives new data aligned with the modulation “B” sampling rate, so the modulation algorithm can now be safely switched to modulation “B”.

[0113] 9) Now, the transistor is completely controlled by the modulation "B".

[0114] Therefore, the present invention provides a method for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode (synchronous) to a second mode, wherein the modes, in particular their modulation operations, have different sampling rates in the system of any of the preceding claims, but are multiples of each other: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) at a time when the sampling times of the modes are consistent, (a) changing the parameters of the regulation device to align with the sampling rate of the modulation device of the second mode, and (b) starting sampling according to the sampling rate of the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period; (3) selecting the output signal of the modulation device of the second mode; (4) deactivating the freewheeling overcurrent control device.

[0115] Asynchronous switching sequence

[0116] In the most general case, different modulation sampling rates are completely asynchronous with each other. Therefore, previous sequences cannot be used. For clarity, asynchronous operation can also be chosen when this sampling rate condition is met.

[0117] Figure 12 The sequence has been explained, and the following steps have been shown:

[0118] 1) Before the switching, the power transistor is controlled by modulation "A". During this period, the motor current phase is sampled at the sampling rate of modulation "A".

[0119] 2) Finally, the mode selection control determines the change in modulation algorithm (from modulation "A" to modulation "B") (time T0).

[0120] 3) It waits for the next sampling time (time T1) of the modulation "A" sampling rate.

[0121] 4) Starting from time T1, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0122] 5) Then, it modifies the regulator parameters to align them with the sampling rate of modulation "B". This modification should only be effective at the sampling time of the next motor phase. Therefore, at this point, the output of the regulator pipeline stage (0506) is still being used to modulate "A".

[0123] 6) Force freewheeling state on the power gates to prevent dead-time violations at modulation switching times. This action must be performed before effective modulation switching.

[0124] 7) Starting from time T2, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0125] 8) However, between sampling times T1 and T2, the effective period is neither the period of modulation "A" nor the period of modulation "B". Therefore, the regulator parameters must be misaligned with this intermediate sampling rate.

[0126] 9) This is why the regulator must ignore the sampling at time T2 (regulator freeze) to avoid poor regulation.

[0127] 10) After a sufficient dead time period, the continued execution state is released (after time T2).

[0128] 11) Simultaneously, the regulator freeze is released to accept the next sample at the modulation "B" sampling rate.

[0129] 12) Now, the transistor is completely controlled by the modulation "B".

[0130] Figure 10 The sequence has been explained, and the following steps have been shown:

[0131] 1) Before the switching, the power transistor is controlled by modulation "A". During this period, the motor current phase is sampled at the sampling rate of modulation "A".

[0132] 2) Finally, the mode selection control determines the change in modulation algorithm (from modulation "A" to modulation "B") (time T0).

[0133] 3) It waits for the next sampling time (time T1) of the modulation "A" sampling rate.

[0134] 4) Starting from time T1, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0135] 5) Then, it modifies the regulator parameters to align them with the sampling rate of modulation "B". This modification should only be effective at the sampling time of the next motor phase. Therefore, at this point, the output of the regulator pipeline stage (0506) is still being used to modulate "A".

[0136] 6) Force dead-time state on the power gates to prevent dead-time violations at modulation switching times. This action is performed simultaneously with modulation switching that utilizes dead-time protection.

[0137] 7) Starting from time T2, the motor phase sampling events are now controlled by the sampling rate of modulation "B".

[0138] 8) However, between sampling times T1 and T2, the effective period is neither the period of modulation "A" nor the period of modulation "B". Therefore, the regulator parameters must be misaligned with this intermediate sampling rate.

[0139] 9) This is why the regulator must ignore the sampling at time T2 (regulator freeze) to avoid poor regulation.

[0140] 10) Simultaneously, the regulator freeze is released to accept the next sample at the modulation "B" sampling rate.

[0141] 11) Now, the transistor is completely controlled by the modulation "B".

[0142] Therefore, the present invention provides a method for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode (asynchronous) to a second mode, wherein the modes, in particular their modulation operations, have different sampling rates (whether or not they are multiples of each other) in the system of any of the preceding claims: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) at the next sampling time of the first mode, (a) changing the regulation device parameters to align with the modulation device sampling rate of the second mode, and (b) starting sampling according to the sampling rate of the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period; (3) selecting the output signal of the modulation device of the second mode only after the next sampling time of the second mode, and deactivating the freewheeling overcurrent control device. The “frozen” period introduces transient uncertainty into the regulation. This is not a major problem because the regulator is a low-pass function, which naturally filters out such artifacts. Furthermore, the problem can be completely solved by always operating the regulator at its maximum frequency.

[0143] The methods of the two inventions can be described as methods for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode to a second mode, said mode, in particular its modulation operation, having a different sampling rate in the system of any of the preceding claims: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) at a first appropriate time, (a) changing the parameters of the regulation device to align with the sampling rate of the modulation device of the second mode, and (b) starting sampling according to said sampling rate of the second mode; (2) activating said freewheeling control device for inserting a freewheeling period; (3) at a second appropriate time, selecting the output signal of the modulation device of the second mode; (4) deactivating said freewheeling control device simultaneously with (3) or after (3).

[0144] Figure 9 and Figure 10 The diagram illustrates the same situation as the dead-time insertion area.

[0145] The above sequence imposes implicit constraints on the logic responsible for executing it. The complete sequence should be shorter than the fastest sampling rate of the modulation.

[0146] This means that the sequence cannot be processed by a software sequence on a random microcontroller alone.

[0147] Therefore, this innovation is well-suited for implementation on FPCU components that provide both CPU computation and embedded FPGA for hard real-time sequences.

[0148] Therefore, a system based on a (electric) motor includes a (digital) control system, which includes software programmable units and / or hardware programmable units, preferably a programmable logic matrix (suitable for hard real-time operation), and thus preferably includes both.

[0149] Therefore, within this invention, it is necessary to determine whether the method (more precisely, which parts of the method) will be governed by the software programmable unit of the (digital) control system or by the hardware programmable unit of the (digital) control system, and to configure it for such purposes.

Claims

1. A (digital) control system for regulating and modulating a (digitally controlled) electric motor, comprising: (1) Adjustment device (0501), adapted to receive adjustment parameters (0502) to align with the sampling rate of the active modulation device; (2) Multiple modulation devices (0504), each with a different sampling rate, all input signals from the modulation devices; (3) Selector (0510), used to select one of the output signals provided by the modulation devices; And (4) a controller (0503) for (a) manipulating the selection of the selector and (b) providing the adjustment parameter (0502) to the adjustment device.

2. The (digital) control system as described in claim 1, wherein, The selector is a demultiplexer.

3. The (digital) control system as described in claim 1 or 2, further comprising: Multiplexer (0520) is used to direct the output signal of the regulating device to the modulation device.

4. The (digital) control system as described in claim 1 or 2, wherein, The output signal of the regulating device is directly provided to the modulation device.

5. The (digital) control system as described in any of the preceding claims, further comprising: One or more additional regulating devices, each of which is provided with its own dedicated modulation device; the selector is also capable of selecting one of the output signals for those dedicated modulation devices; and optionally, a multiplexer is used to direct the system input signal to any of the regulating devices when the output of the additional regulating device is not directly provided to the dedicated modulation device.

6. The (digital) control system as described in any of the preceding claims, further comprising: (5) Dead time insertion device (0505) receives the output of the selector and inserts a dead time period when activated. Optionally, the system is further characterized in that the controller is further adapted to (c) activate the dead time insertion device (via signal (0530)).

7. The (digital) control system as described in any of the preceding claims, further comprising: (5) A continuous current control device (0505) receives the output of the selector and inserts a continuous current period when activated. Optionally, the system is further characterized in that the controller is further adapted to (c) activate the continuous current control device (via signal (0530)).

8. The (digital) control system as described in any of the preceding claims, further comprising: (6) Pipeline stage (0506), located between the regulating device and the multiplexer (if present) and / or between the regulating device and the modulation device, for temporarily storing the regulator output.

9. The (digital) control system as described in any of the preceding claims, wherein, The controller is adapted to execute the switching method.

10. The (digital) control system as described in any of the preceding claims, wherein, The regulating device is a (digital) (low-pass) filter device, suitable for providing (actual motor operating status) information to the controller, which selects a modulation device based on the information.

11. The (digital) control system as described in any of the preceding claims, wherein, The multiple modulation devices support modulation techniques selected from the following groups: SVPWM (Space Vector Pulse Width Modulation), SPWM (Sinusoidal Pulse Width Modulation), THIPWM (Third Harmonic Pulse Width Modulation), DPWM (Discontinuous Pulse Width Modulation), and OPP (Optimized Pulse Mode).

12. A system based on a (electric) motor, comprising: (1) (Electric) motor (0103); (2) (Electric) motor power control device (0102) provided for controlling the (electric) motor; (3) (Digital) control system (0101) as described in any one of claims 1 to 11, adapted to provide control signals to the (electric) motor power control device; (4) (Electric) power storage device (0105) provided for supplying power to the (electric) motor power control device.

13. The system based on a (electric) motor as described in claim 12, wherein, The (electric) motor power control device includes multiple switches (0106) connected in series in pairs.

14. The system based on a (electric) motor as described in claim 12 or 13, wherein, The (digital) control system includes software programmable units and / or hardware programmable units, preferably programmable logic matrices.

15. A method for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode to a second mode, the mode, in particular its modulation operation, having a different sampling rate in the system of any one of the preceding claims: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) at a first appropriate time, (a) changing the parameters of the regulation device to align with the sampling rate of the modulation device of the second mode, and (b) starting sampling according to the sampling rate of the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period, and / or activating the dead-time insertion device (0505) for inserting a dead-time; (3) at a second appropriate time, selecting the output signal of the modulation device of the second mode; (4) simultaneously with (3) or correspondingly after (3) deactivating the freewheeling overcurrent control device and / or the dead-time insertion device (0505).

16. The method of claim 15, suitable for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode (synchronous) to a second mode, wherein the modes, in particular their modulation operations, have different sampling rates in the system of any one of the preceding claims, but are multiples of each other: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) defining the time when the sampling times of the modes are consistent as a first appropriate time, (a) changing the parameters of the regulation device to align with the sampling rate of the modulation device of the second mode, and (b) starting sampling according to the sampling rate of the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period, and / or activating the dead time insertion device (0505) for inserting a dead time; (3) selecting the output signal of the modulation device of the second mode; (4) deactivating the freewheeling overcurrent control device and / or the dead time insertion device (0505) accordingly.

17. The method of claim 15, suitable for switching the regulation and modulation mode of a (digitally controlled) motor from a first mode (asynchronous) to a second mode, wherein the modes, in particular their modulation operations, have different sampling rates (whether they are multiples of each other) in the system of any of the preceding claims: (1) receiving a switching request (to apply a modulation technique suitable for or best suited to a particular motor operating point (speed and / or torque); (2) defining the next sampling time of the first mode as a first appropriate time, (a) changing the regulation device parameters to align with the modulation device sampling rate of the second mode, and (b) starting sampling according to the sampling rate of the second mode; (2) activating the freewheeling overcurrent control device for inserting a freewheeling period and / or activating the dead time insertion device (0505) for inserting a dead time; (3) defining the time only after the next sampling time of the second mode as a second appropriate time, selecting the output signal of the modulation device of the second mode, and accordingly deactivating the freewheeling overcurrent control device and / or the dead time insertion device (0505).

18. A method for selecting which method will be used in the method of claim 16 or 17.

19. The method of claim 18, wherein, After the selection, it is determined whether the method will be dominated by the software programmable unit of the (digital) control system or by the hardware programmable unit of the (digital) control system, and if the hardware programmable unit is selected, the hardware programmable unit is configured for such purposes.

Images