Power supply circuit for providing controlled power supply

Abstract

A power supply circuit includes a control signal circuit including a power control command generation device for receiving or generating a power supply command and generating an internal switching control signal to control a power supply according to the power supply command, and a first electrical separation stage for separating electrical power from the power supply command, an internal switch control signal is received at an input thereof and an output control signal is generated at a separate output thereof. It also includes a power control circuit having a power input terminal connectable to an input power source, a signal input connected to the separate output, a semiconductor power switch for switching on and off power drawn from the power input terminal in accordance with an output control signal from the signal input, a first transformer, comprising a first primary winding connected to one of the semiconductor power switch and the power input terminal and a first secondary winding inductively coupled to the first primary winding, and a power output circuit connected to the first secondary winding and having a power output terminal for providing a controlled power source.

Description

Technical Field

[0001] The present invention relates to a power supply circuit for providing a controlled power supply to an electrical device. The power supply under consideration is AC or DC electricity. The consumers under consideration may be consumers for which safety considerations are relevant in some respects. The safety considerations may relate to the safety of the device by protecting the device from an unsuitable power supply, and / or to environmental safety by protecting the environment of the device from device failures due to power supply failures. As an example, it may be assumed that an electric motor drives a movable carrier in a more or less open environment, which may collide with other components in the environment (e.g. other carriers) if the power supply is unsuitable for one reason or another. Background Art

[0002] The power supply of components is becoming increasingly complex. For example, the primary constant power from a battery pack or the power grid can undergo amplitude conversion and / or frequency conversion and / or power control. In the case of AC, some of this can be done by transformers. In the case of DC, a DC converter based on the chopper principle is required, or a full intermediate AC conversion can be used. For power control, circuits such as chopper circuits or PWM circuits (PWM = pulse width modulation) from DC, or phase angle control of the leading and / or trailing edges from AC, etc. can be provided. The common effect of all these developments is that, on the one hand, more and more components are included in such power supplies, so that the risk of failure also increases accordingly to the number of components involved, and on the other hand, it is becoming increasingly difficult to quickly cut off the power supply in an emergency, because in a chain of cooperating components, the faulty component may not be accessible or can not be immediately identified for appropriate interaction.

[0003] DE 2408381 discloses a control circuit arrangement for power semiconductors, which uses galvanically separated PWM DC.

[0004] US 6807071 B1 discloses a transformer-isolated driver in which an isolation transformer is connected to the gate of a MOSFET.

[0005] Choppers are also known which feed chopped AC to a transformer primary winding for extracting amplitude-converted induced AC power from a secondary winding.

[0006] Known circuits lack adequate protection against faulty components. For example, if a transistor in a PWM driver blows, it may remain "on," resulting in a continuous power supply. Even if an emergency switch were to shut down certain components, it might not achieve the desired effect of quickly bringing the system down to zero. Another drawback of many prior art circuits is that, while galvanic isolation is provided, the isolation between the signal and power sides may be insufficient, and power could be fed back into the signal processing circuitry.

[0007] Furthermore, under regulatory considerations, it is increasingly expected or required that the design of the power circuit 1 complies with standardized safety requirements, particularly SIL_n such as SIL3 or PLe or HFT_n such as HFT1. Summary of the Invention

[0008] An object of the present invention is to provide a power supply circuit designed to reliably cut off power supply in an emergency or failure.

[0009] Another object is to provide a power supply circuit with reliable electrical isolation between the signal side and the power side of the circuit.

[0010] These objects are achieved by the features of claim 1 .

[0011] A power supply circuit for providing a controlled power supply has the features of claim 1. It comprises a control signal circuit including a power control command generating device for receiving or generating a power supply command and generating an internal switch control signal in accordance with the power supply command. The control signal circuit further comprises a first electrically isolated stage for receiving the internal switch control signal and generating an output control signal. The power supply circuit further comprises a power control circuit. The power control circuit comprises a power input terminal connectable to an input power supply, a signal input for receiving the output control signal, a semiconductor power switch for switching power drawn from the power input terminal on and off in accordance with the output control signal, a first transformer having a first primary winding connected to one of the semiconductor power switch and the power input terminal and a first secondary winding inductively coupled to the first primary winding, and a power output circuit connected to the first secondary winding and having a power output terminal for providing a controlled power supply.

[0012] The power supply can have a fixed or adjustable target value. It can include an on / off switch for switching consumers, such as electric motors, on and off accordingly. The power supply can be an input to another power controller, such as an on / off switch, PWM control, or phase angle control in the case of AC output. However, the power supply itself can be generated by quantitative and possibly variable control, for example, to control an electric motor to a desired speed or power consumption that can be variably set by a corresponding target value.

[0013] The term "connected" herein may refer to a direct or indirect connection such that the components referred to as "connected" substantially cooperate. They may receive substantially the same signal and / or the same power. However, such a connection may be direct or indirect, with other components and / or circuit taps intervening.

[0014] The described power supply circuit has two separate stages. One is provided on the signal side as a first electrically separate stage, transferring control signals on the low-power side. The second is the claimed first transformer, in which the primary winding receives the switched input power and converts it to the secondary winding.

[0015] The first transformer implements a fail-safe power supply. It supplies power to connected consumers only when AC power is received on the input side. A blown transistor in either the signal or power branch is unlikely to cause AC power failure, so in the event of such a fault, power to the secondary side of the first transformer ceases. Furthermore, the electrically isolated stage on the signal side significantly reduces the possibility of high electrical power returning to the signal branch.

[0016] The power supply circuit can be considered as having a control branch and a power branch. The control branch can operate at a relatively low voltage, such as less than 30 or 20 or 10 volts. The power branch can operate at a higher voltage, such as more than 20 or 40 or 50 volts, and can be AC or DC.

[0017] The first electrical separation stage can be or include a second transformer having a second primary winding and a second secondary winding. The second transformer is then arranged on the signal side of the circuit and has the fail-safe characteristics of the first transformer used in the power branch of the circuit as described above. If the second transformer does not receive an AC component on its primary side, it will not convert anything to the secondary side. Similarly, the first electrical separation stage can be or include an optocoupler. The optocoupler of the first electrical separation stage can forward an on / off signal for switching downstream power in the power branch of the circuit. The first electrical separation stage specifically prevents high-power rails from the power branch from returning to the signal branch.

[0018] The power control command generating device may include a pulse width modulator. It may have a switching frequency exceeding 5 or 10 or 20 or 50 kHz.

[0019] PWM first generates a series of pulses on the control side and downstream in the power branch. The duty cycle—the on-time relative to the cycle duration—is a key factor in determining the amount of power transferred. Typically, PWM switches a sufficiently high DC power source, such as 48V or 60V. The switching frequency can exceed 1, 2, 5, 10, 20, or 50 kHz.

[0020] The power supply circuit may include an input power terminal connected to an emergency switch at the control signal circuit, the emergency switch being configured to cut off input power in an emergency. The control signal circuit is configured to stop outputting the control signal when a power interruption occurs at the input power terminal. Power from the input power terminal serves as a power source for the control signal circuit.

[0021] The entire emergency shutoff structure can be designed to prevent, inhibit, or stop forwarding pulses to the power control circuit in one way or another. Consequently, no pulses will appear in the power branch, and therefore, when dI / dt = 0, the first transformer will not perform any switching. An emergency circuit can be provided that reacts to a power loss caused by the emergency switch connected to the input power terminal. For example, the emergency circuit can shut off the power supply to the control signal circuit or interrupt the signal output from the first electrical isolation stage. For example, it can open a semiconductor switch in the signal output line or pull the signal output line back to a fixed potential to stop forwarding pulses using the fail-safe characteristics of the first transformer.

[0022] Therefore, once the input power interruption occurs, the emergency circuit may stop the power control command generating device from generating the internal switch control signal, or may interrupt the forwarding of the internal switch control signal or the output control signal.

[0023] The loss of emergency power generated by the emergency switch and received at the input power terminals may itself be a short interruption, may be a longer interruption, or may be a permanent interruption requiring some type of reset.

[0024] The power input terminals of the power control circuit can receive DC as raw input power. The continuous DC at the input terminals is then converted into pulsating DC by the switching activity of the semiconductor power switch and fed into the primary winding of the first transformer. The pulsation can be generated according to a PWM scheme.

[0025] The power output circuit of the power supply circuit may include a rectifier circuit connected to the first secondary winding for rectifying the output voltage of the first secondary winding. On the secondary side of the first transformer, AC will appear in response to the AC component received on the primary side. If DC is required as a controlled power source, the rectifier circuit converts it to DC. This rectification can be half-wave rectification using a single diode, or full-wave rectification using a rectangular diode bridge, providing positive and negative terminals. A smoothing capacitor may be provided on the DC output side of the rectifier circuit to reduce ripple.

[0026] The first transformer may include two or three or more first secondary windings, each first secondary winding is inductively coupled to the first primary winding, and may include a plurality of power output circuits, each power output circuit is connected to a corresponding one of the plurality of first secondary windings, wherein each of the power circuits may include a corresponding rectifier circuit connected to the corresponding first secondary winding, for rectifying the corresponding output voltage of the corresponding first secondary winding.

[0027] The multiple first secondary windings can have the same or different numbers of turns. Accordingly, they will generate the same AC voltage amplitude or different AC amplitudes at the winding terminals, and accordingly, different DC voltages after rectification. For example, the lower voltage output from one secondary winding can be used to feed control circuitry, while the higher amplitude output can be used as a power supply for a motor, etc.

[0028] It should be noted that the purpose of the power supply circuit described is primarily to provide a constant power supply, either AC with a constant amplitude or DC with a constant level. Its output can then be used as input to other control structures, such as a phase angle controller or a PWM controller, for quantitative power control of the consumer.

[0029] In determining the DC output power, the rectifier circuit can follow the AC output of the secondary winding. The rectifier circuit can be or include a diode rectifier. It can be or include a half-wave rectifier or a full-wave rectifier. Two or more rectifiers, particularly full-wave and / or half-wave rectifiers, can be provided functionally in parallel to provide a certain degree of isolation between the output circuits.

[0030] The power supply circuit, and in particular the power control circuit, can be configured to receive AC at the power input terminal, for example, from a normal AC power grid, such as 230V 50Hz or 110V 60Hz. It can also include devices for rectifying and smoothing the received AC, such as a diode bridge rectifier as a full-wave rectifier and one or more smoothing capacitors. The DC then appears again on the primary winding side of the first transformer, where it will be converted into pulses by the semiconductor power switch according to the control signal from the control signal circuit, and then a secondary AC output will be generated at the secondary winding of the first transformer.

[0031] In the described power supply circuit, the control signal circuit may include a control input terminal for receiving a power command. However, the circuit can also be designed without an externally accessible power command input terminal, and thus provide fixed values defined by its structure. However, the control signal circuit may include one or more safety control terminals, particularly for shutting off power generation. It may also have an input for manually operating an emergency switch. It may also have an input for automatically monitoring the resulting signal, causing power generation to be shut off.

[0032] The power command can be explicitly provided in the control signal circuit, or it can be implicitly implemented by various other circuit parameters of the control signal circuit. It can be a qualitative on / off signal and / or it can be a quantitative indication that conveys some quantitative information about the desired power supply, such as its DC level or AC amplitude target value. The PWM modulator will convert such a command into an appropriate pulse duty cycle to forward to the power stage of the circuit. But again, regarding quantity, the circuit parameters may, for example, have a fixed duty cycle for PWM control, and no control input terminal may be provided.

[0033] The switching on and off of the entire circuit may be accompanied by switching on and off the power supply of the entire circuit elsewhere. However, the circuit may also have an on / off switch (not shown) for switching various components on and off together.

[0034] A feedback circuit may be provided between the power output circuit and the power control command generation device. This circuit may provide output power feedback or output voltage feedback. This circuit may also provide feedback of monitoring results to facilitate possible power generation shutdown. The feedback circuit may include a second electrical isolation stage, which may include an optocoupler.

[0035] The feedback circuit can provide feedback of qualitative or quantitative signals in a specified analog or digital format. It can feed back sensed quantities from the power control circuitry of the power stage, particularly from the secondary winding of the first transformer or downstream thereof, and more particularly from the output of a rectifier circuit if provided, to the control signal circuitry for appropriate processing there. The feedback signal can be compared with a target value, target range, or threshold value, which is either pre-set or hard-coded into the circuitry, or provided by an input, such as the aforementioned control input terminal. The feedback circuit is designed so that the feedback value reflects the output voltage or output power of the power supply circuit in some manner, thereby ultimately enabling feedback control of the power supply circuit. The feedback circuit can have a suitable signal tap on its input side, i.e., on the secondary winding side of the first transformer, such as a voltage tap at the output, and can also include a signal shaping circuit. Any second electrically isolated stage can be adapted for quantitative signal transmission, thereby enabling the feedback of quantitative information via the second electrically isolated stage.

[0036] The feedback circuit may alternatively or alternatively feed back a processing result obtained in the power control circuit to the control signal circuit, such as a known yes / no result signal of target value monitoring, target range monitoring, or threshold monitoring performed in the power control circuit. In the monitoring control signal circuit, such a feedback result signal may be used to interrupt power supply.

[0037] The winding ratio of the first transformer, defined as the number of turns of the one or more first secondary windings divided by the number of turns of the first primary winding, may be greater than 0.2 or 0.5 or 0.8 and may be less than 10 or 5 or 2 or 1.5. Similarly, the winding ratio of the second transformer, defined as the number of turns of the second secondary winding divided by the number of turns of the first primary winding, may be greater than 0.2 or 0.5 or 0.8 and may be less than 10 or 5 or 2 or 1.5. The duty cycle of the PWM modulator that may be provided may be a fixed value, which may be greater than 0.2 or 0.3 or 0.4 and may be less than 0.8 or 0.7 or 0.6, or may be determined according to a power supply command (PSC) received at the control input terminal.

[0038] The mentioned figures reflect the fact that the transformer provided and the possibly provided PWM modulator are not so much intended for quantitative power control as for the mentioned fail-safe characteristics of the transformer, in combination with pulsating signals or power.

[0039] The power consumption system comprises a power consumer and a power supply for the consumer. The consumer may be or include an electric motor, in particular a rotary or linear motor of a carrier system, or may be or include a heater, a machine tool, control or computer equipment, lighting, etc. The power supply has a power supply circuit as described or claimed and supplies power directly or indirectly to the consumer. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Hereinafter, embodiments of the present invention will be explained with reference to the accompanying drawings, in which:

[0041] Figure 1 is a schematic block diagram of various aspects of the present invention,

[0042] Figure 2a and 2b shows the electrical separation level,

[0043] Figure 3 shows an embodiment of a power output circuit,

[0044] Figure 4 shows the feedback structure,

[0045] Figure 5 shows the overall circuit, and

[0046] Figure 6 The prior art is shown. DETAILED DESCRIPTION

[0047] Figure 1A power supply circuit 1 is shown having a control signal circuit 10 and a power control circuit 20. The control signal circuit 10 has input power terminals 16 and 17 for its power supply and includes a power control command generator 11 that generates an internal switch control signal ISCs, which may be a pulse train. The pulse train of the internal switch control signal ISCs is generated based on a power command PSC, which may be permanently stored in the circuit or received externally from terminals not shown. The input power at terminals 16 and 17 may be AC or DC. It may be relatively low, perhaps less than 50, 30, 20, or 10 volts. It may be higher than 10 or 20 volts. It may ultimately be supplied as DC to the various components of the control signal circuit 10.

[0048] The control signal circuit 10 further includes a first electrically isolated stage 12, into which the internal switch control signal iscs is input and at whose output the output control signal ocs is present. The internal switch control signal iscs may be a pulse train, and the output control signal may be a corresponding pulse train electrically isolated from the upstream circuit.

[0049] The power control command generating device 11 may include an inverter or a chopper or a pulse width modulator 13, which generates a pulse signal, in particular a pulse width modulated signal, as the internal switch control signal ISCs. The pulses may have a fixed pulse frequency or a fixed or adjustable duty cycle. The pulse frequency may be higher than 1, 2, 5, 10, 20, or 50 kHz. It may be lower than 100, 50, or 20 kHz. The duty cycle may be defined as the ratio of the on-time to the cycle duration. It may be a fixed value higher than 0, 1, 0, 2, or 0, 4. It may be lower than 0.9, 0.8, or 0.6. However, similarly, the duty cycle of the pulse width modulator 13 can be adjusted according to the power supply command PSC, which can be received from the control input terminal of the power supply circuit 1 (not shown in the figure).

[0050] Reference numeral 9 denotes an external emergency switch, which may be, for example, a readily accessible and easily visible push-button switch that can be activated in an emergency. It is normally closed, i.e., conductive, to supply power to the power control command generating device 11. In an emergency or similar situation, it can be automatically and / or manually opened, i.e., non-conductive, to interrupt at least one input power line to terminal 16 or 17, thereby shutting off power to the power control command generating device 11 and preventing the control signal circuit 10 from generating signals to its output. External emergency switch 9 can be connected to one or both of the input power terminals 16 and 17 for connecting and disconnecting them from the power source.

[0051] Emergency switch 9 can be a mechanical or semiconductor switch. It can be manually operated and / or automatically operated. Automatic operation can be controlled by some type of monitoring device that identifies predetermined undesirable conditions requiring power interruption in a predetermined manner. Emergency switch 9 can have two stable switching states, "on" and "off," requiring switching from one to the other in response to a corresponding command or manual or automatic condition.

[0052] The arrangement can also be such that, when the switch 9 interrupts input power, the forwarding of the internal switch control signal ICS is actively interrupted, for example, by interrupting the signal line with a suitable switch (e.g., an electronic switch such as a switching transistor), or by pulling the signal line carrying the internal switch control signal ICS or the output control signal OCS to a fixed potential, again via some electronic switch such as a switching transistor. As a result, the forwarding of the pulse train serving as the output control signal OCS is quickly disabled, so that no output control signal reaches the power control circuit. This also applies to situations where pulse generation in the power control command generating device 11 has ceased due to certain circuit faults.

[0053] Figure 1 20 in the figure is a power control circuit of the power stage. It has a signal input. Figure 1 Terminal 22 is represented in the figure. This input receives the output control signal ocs from control signal circuit 10, specifically from isolator 12. This is the pulse train mentioned above. It passes through some type of driver circuit 25 and is used to control at least one semiconductor power switch 23. This switch 23 can be a power MOSFET that receives the drive signal from input 22 or driver 25 at its gate, or it can be an IGBT that receives the signal at its base. Power switch 23 is connected in series with the primary winding 24-1 of a first transformer 24.

[0054] Generally speaking, "connected in series" here means receiving substantially the same current, and may mean, but does not necessarily mean, that the components are directly connected to each other. Other circuit elements may be between them, and there may be taps between them for deriving potential or small amounts of current, such as for signaling or control purposes.

[0055] The series connection of the power switch 23 and the primary winding 24-1 of the first transformer 24 is connected to the power input terminal 21 for receiving input power ip. Preferably, the input power is a constant DC voltage at a desired level. However, it can also be AC voltage that is rectified and smoothed before reaching the primary winding 24-1 of the first transformer 24. The secondary winding 24-2 is inductively coupled to the primary winding 24-1 of the first transformer 24. When the power passing through the primary winding 24-1 of the first transformer 24 is repeatedly switched on and off by the power switch 23 in accordance with the received output control signal ocs, the first transformer 24 experiences an AC component in its primary winding and induces a corresponding magnetic field in the secondary winding 24-2, thereby generating an AC signal at the terminals of the secondary winding 24-2.

[0056] Secondary winding 24-2 is connected to a power output circuit 27, which directs the electrical power present at secondary winding 24-2 to power output terminals 28, more or less as the desired controlled power source CSP. If AC is desired as the controlled power source CSP, the voltage from secondary winding 24-2 can be forwarded more or less directly to power output terminals 28. Conversely, if DC is desired, power output circuit 27 can include a rectifier circuit. This can be a diode rectifier. This can be either a full-wave diode rectifier or a half-wave rectifier.

[0057] The turns ratio of the primary winding 24-1 and the secondary winding 24-2 of the first transformer 24 can be approximately 1, for example between 0.9 and 1.1. The circuit to be protected can be adapted to be connected to an existing power supply to provide electrical isolation and the aforementioned fail-safe features. In this case, the output level of the controlled power supply csp at terminal 28 should be the same as the DC level of the input power ip at terminal 21. One or both can be a DC voltage level greater than 10, 20, or 50 V and / or can be less than 100 or 50 V.

[0058] Preferably, the control signal circuit 10 and the power control circuit 20 do not have a common ground, but rather have independent, unconnected ground lines.

[0059] In case pulse width modulation is used in the power control command generating device 11, its duty cycle may be substantially 0.5, for example between 0.45 and 0.55.

[0060] Figure 2a Shown Figure 1An example of a first electrically separated stage 12 is shown in FIG. It is formed as a second transformer 14 having a primary winding 14-1 and a magnetically coupled secondary winding 14-2. Signal flow is from left to right. At its input, it receives internal switch control signals from the power control command generation device 11, which, as described above, can be PWM pulses. These signals have an AC component that reaches the primary winding 14-1 and is converted to the secondary winding 14-2. A signal shaping circuit 121 can be provided on the secondary side of the second transformer 14 to shape the output signal in the desired manner, in particular, to form a more or less rectangular pulse train that can be used, for example, for PWM.

[0061] Likewise, if no pulse train reaches the primary winding 14-1, no voltage will be induced in the secondary winding 14-2.This provides an inherent fail-safe behavior in the event that the pulse train generation is inoperative or interrupted.

[0062] Figure 2b An optocoupler is shown as an example of a first electrical isolation stage 12. It comprises a light emitter 15-1 of some type, such as an LED, and a light receiver of some type, such as a photodiode 15-2. In the embodiment shown, the light emitting diode 15-1 and the photodiode 15-2 together form the optocoupler 15. On the output side, if necessary, a light emitting diode 15-1 can be provided. Figure 2a The signal shaping circuit 121 is shown for providing a shaped pulse train.

[0063] Figure 3 An example of a power output circuit 27 of the power control circuit 20 is shown. It is a full-wave rectifier with diodes 31-1, 31-2, 31-3, and 31-4. Its AC input terminals are connected to the secondary winding 24-2 of the first transformer 24. Its DC terminals can be coupled more or less directly to the power output terminals 28 of the power supply circuit 1. A smoothing device, such as a capacitor 32, can be provided on the DC side.

[0064] Figure 4 A possible feedback structure is shown. It feeds back the voltage-related value from the power control circuit 20 to the control signal circuit 10. In more detail, it can capture the signal from the power output circuit 27 and, again in more detail, it can send the output voltage-related value from there. For example, in Figure 3 In this case, it can receive a DC output voltage from terminal 28 , which voltage also appears across capacitor 32 .

[0065] A suitable signal shaping device 30 may be provided in the feedback branch. It may comprise a second electrical separation stage. Depending on the quality of the input signal, it may be Figure 2a or as explained in 2b, however, the signal flow is from right to left. The separation stage can be applied to quantitative signal forwarding, in Figure 4 From right to left in the middle. In the control signal circuit 10, and in particular in the power control command generation device 11, the feedback value can be appropriately processed. In particular, it can be calculated based on the deviation between the actual value and the target value by providing a controller with appropriate control characteristics, against which a possible command value can be provided. More or less regular feedback structures can be implemented using a device for determining the difference between a given target value and the fed-back actual value, and a controller having this difference as input and suitable characteristics.

[0066] Figure 5 The overall circuit is shown. The same numbers as in the previous figures represent the same components. The power control command generating device 11 can be formed as an inverter or a PWM controller 13. The switch 9 shown here is used to connect / disconnect the two input power terminals of the PWM controller 13, corresponding to Figure 1 Terminals 16 and 17 in the Figure 2a As shown, the first isolation stage 12 is formed by the second transformer 14. A driver circuit 25, comprising a resistor and a voltage-limiting Zener diode, is connected to the ground of the circuit on the primary side of the first transformer 24. An emergency switch 9 is connected to interrupt the power supply to the PWM controller. The control signal circuit 10 can be designed to operate at a first DC voltage level, e.g., greater than 10, 15, or 20 volts, e.g., less than 30 or 20 volts. The direction from left to right in the figure indicates signal flow.

[0067] The direction from top to right represents power flow. The power control circuit 20 can be configured to operate at a higher DC voltage, preferably greater than 40 or 50 volts, which can be less than 100 or 80 volts. The first transformer 24 has a primary winding 24-1 and can have one or, as shown, two or more secondary windings 24-2 and 24-3 on the secondary side. They are functionally provided in parallel and can have different numbers of turns to produce different voltage levels. The parallel secondary windings provide a certain degree of isolation for the output circuits connected to each. Each secondary winding 24-2 and 24-3 can have one or more power output circuits 27-1 and 27-2 of its own, preferably for constant AC or DC.

[0068] In the embodiment shown, a DC output is desired. Therefore, the power output circuit 27 has diodes for rectification, in particular half-wave or full-wave rectification. Figure 5 Two independent, functionally parallel rectifiers are shown connected to one of the secondary windings. These parallel rectifier windings provide some isolation between the output circuits to which they are connected. Smoothing devices may be provided. Two identical or similar rectifiers may be arranged in parallel on one or more secondary windings, with individual detection devices on each secondary winding to allow cross-checking between them for fault detection.

[0069] Preferably, the secondary side or winding of the first transformer 24 is electrically isolated from its primary side. Therefore, the ground planes of the two transformer sides will also be different and unconnected. Similarly, the control signal circuit 10 is preferably completely electrically isolated from the primary side of the first transformer 24, meaning that the ground of the control signal circuit 10 is also different from the ground of the primary side of the first transformer 24.

[0070] The described power supply circuit is preferably a power supply circuit for providing one or more different constant DC voltages in parallel. The adjustable target value may not be desired. However, the described feedback can be provided to accurately control the desired fixed target voltage level.

[0071] The DC voltage at output terminal 28 can be used to drive a movable component, such as a carrier in a track-based multi-carrier system. The carrier is driven by a control component for controlling the carrier, which can receive the output from the output terminal as its power input. The control component can again include a power control for controlling the dynamic characteristics of the controlled carrier. In this case, the power control can again be, for example, PWM. Thus, the claimed power supply circuit can provide one or more nominal output DC voltages at its output terminals 28, 28-1, and 28-2. These terminals can be connected to the power input of a PWM controller used to control the carrier.

[0072] The design of the power circuit 1 can comply with standardized safety requirements, in particular SIL standards such as SIL3 or PLe or HFT standards such as HFT1. The two separation stages provide reliable separation of the various circuit stages and, in the case of a transformer, the mentioned fail-safe characteristics.

[0073] Another aspect of the present invention is a power consumption system comprising a power consumer and a power supply for the consumer. The consumer may be a motor, in particular a rotary or linear motor of a carrier system, or a heater, a machine tool, computer equipment, lighting equipment, etc. The power supply comprises a power supply circuit as described or claimed. It may also include a PWM controller or a phase angle controller between the output terminal 28 of the power supply circuit and the power input of the consumer.

[0074] Features described in this specification and / or claims and / or shown in the drawings should be considered combinable with one another, unless such combination is explicitly described, to the extent that such combination is technically feasible. Features described in a particular context, embodiment, figure, or claim should be considered separable from that claim, context, embodiment, or figure and combined with every other figure, claim, context, or embodiment to the extent that such combination is technically feasible. The embodiments and figures should not be interpreted as necessarily excluding each other. Features described as part of an embodiment or figure should be considered separable from that embodiment or figure and combined with features of other embodiments or figures to the extent technically feasible. A description of a method, process, or method step or process step should also be understood as a description of an apparatus for implementing the method, process, or method step or process step, and / or a description of an article produced or modified by the method, process, or method step or process step, and / or a description of a data carrier storing program instructions for implementing the method, process, or method step or process step, and vice versa. In this specification, references to "invention" refer to the teachings of the inventor's subjective conception.

[0075] Reference Signs List

[0076] 1 Power supply circuit

[0077] 9 Emergency switch

[0078] 10 Control signal circuit

[0079] 11 Power control command generation device

[0080] 12First separation stage

[0081] 13 Pulse Width Modulator

[0082] 14 Second transformer

[0083] 14-1 Primary Winding

[0084] 14-2 Secondary Winding

[0085] 15 Optocoupler

[0086] 15-1 LED

[0087] 15-2 Photodiode

[0088] 16,17 input power terminals

[0089] 20 Power control circuit

[0090] 21 power input terminal

[0091] 22 signal input terminals

[0092] 23Semiconductor switches

[0093] 24 First Transformer

[0094] 24-1 Primary Winding

[0095] 24-2 Secondary Winding

[0096] 24-3 Secondary Winding

[0097] 25 drives

[0098] 27 Power output circuit

[0099] 28, 28-1, 28-2 power output terminals

[0100] 29 rectifier circuit

[0101] 30 Feedback circuit

[0102] 31 diode rectifier

[0103] 31-1 to 31-4 diodes

[0104] 32 capacitors

[0105] 121 signal shaping circuit

Claims

1. A power supply circuit for providing controlled power, comprising: (a) Control signal circuit, including: (a1) a power control command generating device for receiving or generating a power command and generating an internal switch control signal to control the power supply according to the power command, (a2) a first electrical separation stage receiving the internal switch control signal at its input and generating the output control signal at its separation output, and (b) a power control circuit comprising: (b1) a power input terminal, which can be connected to an input power source to receive input power, (b2) a signal input connected to the separation output for receiving the output control signal from the control signal circuit, (b3) a semiconductor power switch for switching power drawn from the power input terminal on and off according to an output control signal from the signal input, (b4) a first transformer including a first primary winding connected to one of the power input terminals and the semiconductor power switch and a first secondary winding inductively coupled to the first primary winding, and (b5) A power output circuit connected to the first secondary winding and having a power output terminal for supplying controlled power. 2 . The power supply circuit according to claim 1 , wherein the first electrically separated stage comprises a second transformer having a second primary winding and a second secondary winding, or comprises an optocoupler.

3. The power supply circuit according to claim 1, wherein the power control command generating device comprises a pulse width modulator with a switching frequency exceeding 5 or 10 or 20 or 50 kHz, The duty cycle of the PWM modulator is a fixed value greater than 0.2 or 0.3 or 0.4 and less than 0.8 or 0.7 or 0.6, or is determined according to a power command received at a control input terminal.

4. The power supply circuit according to claim 1 , comprising an input power terminal at the control signal circuit for connecting an emergency switch configured to interrupt power supply to the power terminal, wherein the control signal circuit is configured to stop outputting the output control signal when a power interruption occurs at the input power terminal, and wherein the power control command generating device is configured to stop generating the internal switch control signal or interrupt forwarding of the internal switch control signal or the output control signal when the power interruption occurs. 5 . The power supply circuit according to claim 1 , wherein the control signal circuit comprises a control input terminal for receiving a power supply command. 6 . The power supply circuit according to claim 1 , wherein the power control circuit is configured to receive DC as input power at the power input terminal, wherein a voltage level of the DC is greater than 10 or 20 or 50 V and / or less than 100 or 50 V.

7. The power supply circuit according to claim 1 , wherein the first transformer comprises a plurality of first secondary windings, each first secondary winding being inductively coupled to the first primary winding, and a plurality of power output circuits, each power output circuit being connected to a corresponding first secondary winding, wherein each of the power circuits comprises a corresponding rectifier circuit connected to a corresponding first secondary winding for rectifying a corresponding output voltage of the corresponding first secondary winding, The rectifier circuit includes one or more half-wave rectifier circuits or full-wave rectifier circuits.

8. The power supply circuit according to claim 7, wherein the rectifier circuit is formed by one or more diodes and a smoothing device, and comprises a voltage monitoring device or a voltage monitoring tap for feedback purposes.

9. A power supply circuit as claimed in claim 8, wherein the smoothing device is formed by one or more capacitors.

10. The power supply circuit of claim 1, configured to receive DC at the power input terminal.

11. The power supply circuit of claim 1, configured to receive AC at the power input terminal, and comprising means for rectifying and smoothing the received AC. 12 . The power supply circuit according to claim 1 , wherein the control signal circuit comprises a control input terminal for receiving a power supply command. 13 . The power supply circuit according to claim 1 , further comprising a feedback circuit between the power output circuit and the power control command generating device, the feedback circuit being configured to provide output power feedback or output voltage feedback.

14. The power supply circuit of claim 13, wherein the feedback circuit comprises a second galvanic separation stage comprising an optocoupler.

15. The power supply circuit according to claim 7, comprising a feedback circuit between the power output circuit and the power control command generating device, configured to provide output power feedback or output voltage feedback, and wherein the feedback circuit is connected to the output side of the rectifier circuit.

16. The power supply circuit of claim 15, wherein the feedback circuit comprises a second galvanic separation stage comprising an optocoupler.

17. The power supply circuit according to claim 1, wherein a turns ratio of the first transformer is defined as the number of turns of the first secondary winding divided by the number of turns of the first primary winding, and the turns ratio is greater than 0.2 or 0.5 or 0.8 and less than 10 or 5 or 2 or 1.

5.

18. The power supply circuit of claim 1, wherein the first electrically separated stage comprises a second transformer having a second primary winding and a second secondary winding, or comprises an optocoupler, and wherein, The turns ratio of the second transformer is defined as the number of turns of the second secondary winding divided by the number of turns of the first primary winding, and the turns ratio is greater than 0.2 or 0.5 or 0.8 and less than 10 or 5 or 2 or 1.

5.

19. A power consumption system comprising: Power consumers, and A power supply for the consumer, the power supply comprising the power supply circuit according to claim 1 , wherein the power supply further comprises a PWM controller or a phase angle controller, the input of which is connected to the output terminal of the power supply circuit.

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