Multi-axis modular electronic drive system

Abstract

A multi-axis modular electronic drive system includes an input module; an inverter module, the inverter module stacked atop the input module, and a control module, the control module stacked atop the inverter module. The input module, the inverter module, and the control module communicate with one another both fluidly and electrically. Additional inverter modules can be stacked atop one another in the disclosed system without interrupting the fluid and electrical connectivity between the other system modules.

Description

MULTI-AXIS MODULAR ELECTRONIC DRIVE SYSTEMTechnical Field

[0001] This disclosure relates to variable frequency drives. More specifically, this disclosure relates to an electronic drive system employing circulated coolant to reduce temperature of various system components.Background

[0002] It is quite common for original equipment manufacturer (OEM) industrial equipment to utilize multiple independent electric motors to facilitate the equipment function. This could include multi-stage conveyor systems, multi-axis machining systems, filtration systems, process chillers, hydraulic power units, etc. Traditionally, this equipment would be constructed using fixed speed induction motors where the motor speed is a function of the AC electrical power frequency (typically 60Hz in the United States (US) or 50Hz in Europe and many other parts of the world) and the number of poles in the motor construction. This means that a piece of equipment designed in the US for 60Hz operation will often need a different motor to achieve the same performance in Europe where the power supply frequency is 50Hz. Another complication in selecting motors for OEM equipment is the variation in supply voltage standards. The US alone has power supply standards of (208V / 3<D / 60Hz, 230V / 3 > / 60Hz, 440V / 3<D / 60Hz, 480V / 3 / 60Hz). In Europe, the power supply standards are more harmonized to 400V / 3 / 50Hz. Even in Japan, the power supply varies from 200V / 3 / 50Hz to 415V / 3O / 60Hz. Another factor that has complicated electric motor standardization in the last few years has been the introduction of the new Premium and Super Premium efficiency regulations. Under the old efficiency standards, it was possible for motor manufacturers to design motors where the same motor could be wired differently to accept several different supply voltage / frequency combinations. The new efficiency standards make this much more difficult if not impossible.

[0003] One solution to standardizing the motors used on OEM equipment is the implementation of Variable Frequency Drives (VFD’s) to run the motors. A VFD is an electronic device that converts the AC mains power input into a high voltage direct current (DC) bus and then converts the DC voltage to a variable frequency AC voltage output. Since the speed of an induction motor is directly related to the applied AC power frequency, the motor speed can be varied by changing the frequency of the output waveform from the VFD. A typical circuit diagram for a VFD is shown in FIG. 1 . This ability to vary the motor speed can enable OEM equipment that is constructed with the same motors to achieve the same performance with both 60Hz and50Hz mains power. The VFD electronics are typically compatible with a relatively wide voltage range as well so the same equipment can be used in North America with 460V / 30 / 60Hz supply power and in Europe with 400V / 3<I) / 50Hz supply power for instance. In addition to standardizing the motors for supply voltage, the ability to run the same motor over a wide speed range can enable the same piece of equipment to be used over a much wider application range as well. For instance, process chillers typically use induction motor driven centrifugal pumps to supply coolant to the equipment they are cooling. It is very typical that the equipment being cooled by the chiller (an MRI scanner as an example) has very specific coolant flow and pressure requirements to operate properly. This could mean that several different MRI manufacturers could have similar cooling capacity requirements for their scanners but very different coolant pressure and flow requirements. If fixed speed pumps are used to construct the chiller, each customer would require a different chiller to meet their needs. However, if a VFD is used to run the pump, the same pump could be used to meet the requirements for each customer application. This would minimize the number of different pump models the chiller manufacturer is required to inventory and would significantly simplify their manufacturing process.

[0004] In addition to pumps, chillers also have compressors and fans that are driven by electric motors. Traditionally the compressors and fans were also run by induction motors. Today, state- of-the-art compressors and fans utilize variable speed Permanent Magnet (PM) Brushless DC (BLDC) motors. The variable speed fans enable the chillers to operate over a very wide range of ambient temperatures so the same chiller can be used for both indoor and outdoor applications. The variable speed fans are not only more efficient than fixed speed fans when the chiller is operating at part load conditions, but they are also significantly quieter. Furthermore, the BLDC motor construction is cheaper to manufacture than induction motors and they are more efficient as they do not rely on slip speed between the rotor and stator to induce current in the rotor to build the magnetic field in the rotor.

[0005] There are several advantages of using variable speed compressors in chillers and heat pumps. First, this equipment is typically sized to provide heating and cooling for the absolute worst case operating conditions (extreme ambient & highest load). Therefore, the equipment regularly operates at part load conditions. This means that to control the process temperature, fixed speed compressors must be cycled on and off, which impacts reliability, or another means of refrigeration capacity control must be implemented. A common capacity control method utilized with fixed speed compressors is to install a motorized valve that bypasses the hot gas from the compressor discharge around the condenser. This capacity control method is effective, but it is very inefficient as the compressor runs constantly and the unused energy is thrownaway as excess heat from the system. Variable speed compressors provide a more elegant and efficient method of modulating cooling / heating capacity. Furthermore, variable speed compressors are also cheaper per cooling / heating kilowatt than their equivalent capacity fixed speed counterparts. This is because variable speed compressors commonly operate up to 100- 120 revolutions per second, whereas fixed speed compressors only spin at 50-60 revolutions per second. This means that for a given cooling / heating capacity, the variable speed compressors can be significantly smaller in size than fixed speed compressors while having the same volume displacement.

[0006] Despite the advantages that VFD’s provide in product portfolio simplification and efficiency, there are many OEM equipment applications where they are still not widely adopted. There are three primary challenges that have inhibited their adoption. First, cost is a significant barrier. Even with volume pricing, commercial VFD’s for pumps and fans in the 2-7Hp range typically cost $200-3500. Compressor VFD prices are even more substantial, ranging from $700-$1500 for 5-40Hp models. This means that the combined VFD cost for the fan, compressor, and pump is $1100-$2500 for a chiller. Although some of this cost would be recuperated through lower electrical power consumption, the purchasing decisions for OEM equipment are often made by equipment integrators who are selling a larger system to the end customer. Therefore, the end customer is often not involved in specifying the individual equipment making up the system. The second challenge with implementing commercial VFDs on OEM equipment is the amount of physical space required for the VFDs. Typically, the VFDs must be mounted in an electrical cabinet to meet UL electrical safety requirements. The VFDs themselves are usually quite large due to the large heat sinks and fans required to move the heat from the power electronics to the air. Finally, when installing commercial VFDs in an electrical enclosure, care must be taken to ensure that the air temperature within the enclosure is managed since the VFDs are putting the heat from the power electronics into the air. Especially when installing multiple VFDs, it may be necessary to add fan cooling or an enclosure air conditioner to manage the enclosure air temperature.

[0007] To address the challenge of standardizing the electric motors used on equipment, especially OEM equipment that has multiple axes of motion and must be cost effective, it has been known to employ a common rectifier and filter circuit to feed a DC bus that supplies multiple independent inverter circuits, as exemplified in U.S. Patent No. 5,444,357 to lllingsworth. Such an arrangement can eliminate a significant number of power electronic and filter components used in a multi-axis system. Existing VFD systems such as the Danfoss VACON® NXP Liquid Cooled Drive System incorporate this type of common DC busarchitecture and can even be liquid cooled. However, they are not optimized for cost and use in OEM equipment as the design presented herein. The Danfoss VACON® NXP system is designed for use in heavy duty marine and industrial applications where the drives are panel mounted in large electrical cabinets. The design presented herein is a hermetically sealed standalone electronic module that can be installed anywhere within the equipment it is supporting independent of an electrical cabinet. Furthermore, it has been optimized to minimize size and enable maximum application flexibility when used with OEM equipment.SUMMARY

[0008] It is to be understood that this summary is not an extensive overview of the disclosure. This summary is exemplary and not restrictive, and it is intended to neither identify key or critical elements of the disclosure nor delineate the scope thereof. The sole purpose of this summary is to explain and exemplify certain concepts of the disclosure as an introduction to the following complete and extensive detailed description.

[0009] In accordance with some embodiments of the present disclosure, a novel multi-axis modular electronic drive system significantly reduces the number of cooling components for the electronic system, standardizes electric motors used on equipment, and overcomes the drawbacks discussed above. The multi-axis modular electronic drive system can comprise an input module as described below, an inverter module as described below, the inverter module stacked atop the input module, and a control module as described below, the control module stacked atop the inverter module. The input module, the inverter module, and the control module communicate with one another both fluidly and electrically. Additional inverter modules can be stacked atop one another in the disclosed system without interrupting the fluid and electrical connectivity between the other system modules.

[0010] In some aspects of the present disclosure, an input module for an electronic drive system, comprises an input module housing, the input module housing defining a cavity and an upper end, the upper end defining an opening of the input module housing; a rectifier cooling plate received upon the upper end of the input module housing, the rectifier cooling plate comprising rectifier cooling plate comprising a peripheral bearing portion configured to bear against the upper end of the input module housing, a hub extending axially upwardly from the peripheral bearing portion and terminating in a ridge, the hub defining an inner wall, a first opening, a second opening, and a spoke plate projecting inwardly from the inner wall, the spoke plate defining an upper surface and a lower surface; an input module printed circuit board (PCB) at least partially covering the opening of the input module housing, the input module PCB andthe rectifier cooling plate supporting a rectifier circuit, the rectifier circuit comprising an input and an output, the input of the rectifier circuit configured to communicate with at least one of a single-phase alternating current (AC) power source and a three-phase AC power source, and the output of the rectifier circuit communicating with a direct current (DC) filter circuit, the DC filter circuit comprising a filter capacitor and a filter inductor connected in series, the filter capacitor and the filter inductor received in the cavity of the input module housing, wherein the input module PCB further supports a DC bus communicating with an output of the DC filter circuit; a coolant supply assembly comprising a supply conduit defining an inlet and a supply conduit chamber, the supply conduit extending through the first opening in the hub of the rectifier cooling plate, at least a portion of the supply conduit contacting the upper surface of the spoke plate, and an input module supply nipple fluidly communicating with the supply conduit chamber, the input module supply nipple configured to direct coolant axially upwardly from the supply conduit chamber; and a coolant return assembly comprising a return conduit defining an outlet and a supply conduit chamber, the return conduit extending through the second opening in the hub of the rectifier cooling plate, at least a portion of the return conduit contacting the upper surface of the spoke plate, and an input module return nipple fluidly communicating with the return conduit chamber, the input module return nipple configured to direct coolant axially downwardly into the return conduit chamber.

[0011] In other aspects of the present disclosure, an inverter module for an electronic drive system comprises an inverter module housing, the inverter module housing defining an inverter module housing, the inverter module housing defining an inverter module wall, the inverter module wall defining an upper end, a lower end, and an opening, the lower end configured to bear against an inverter cooling plate of an input module; an inverter module printed circuit board (PCB), the inverter module PCB at least partially covering the opening, the inverter module PCB configured to communicate with an output of a DC bus located in the input module, the inverter module PCB defining a first opening and a second opening; an inverter cooling plate attached to the lower end of the inverter module housing, the inverter cooling plate defining a first opening axially aligned with the first opening in the inverter module PCB, the inverter cooling plate further defining a second opening axially aligned with the second opening in the inverter module PCB; a stackable supply nipple defining an inlet end, an outlet end, and a supply nipple chamber extending between the inlet end and the outlet end, wherein the stackable supply nipple is supported by the inverter cooling plate such that the stackable supply nipple extends upwardly through the first opening in the inverter module PCB and the supply nipple chamber is axially aligned with the first opening in the inverter cooling plate; and astackable return nipple defining an inlet end, an outlet end, and a return nipple chamber extending between the inlet end and the outlet end, wherein the stackable return nipple is supported by the inverter cooling plate such that the stackable return nipple extends upwardly through the second opening in the inverter module PCB and the return nipple chamber is axially aligned with the second opening in the inverter cooling plate.

[0012] In further aspects of the present disclosure, a control module for an electronic drive system comprises a control module housing, the control module housing defining an upper end, a lower end, and a control module wall extending between the upper end and the lower end, the lower end defining a lower opening; a control module printed circuit board (PCB), the control module PCB at least partially covering the lower opening of the control module housing, the control module PCB defining an opening; a coolant return tube defining an inlet and an outlet, the inlet configured to fluidly communicate with an outlet end of a stackable supply nipple positioned beneath the coolant return tube, the outlet configured to fluidly communicate with an inlet end of a stackable return nipple positioned beneath the coolant return tube; and a control module cooling plate attached to lower end of the control module housing, wherein the control module cooling plate defines a first opening, the first opening of the control module cooling plate defining the inlet of the coolant return tube, and the control module cooling plate further defines a second opening, the second opening of the control module cooling plate defining the outlet of the coolant return tube.

[0013] In further aspects of the present disclosure, an electronic drive system comprises the input module described above; the inverter module described above, the inverter module stacked atop the input module; and the control module described above, the control module stacked atop the inverter module; wherein the input module, the inverter module, and the control module are configured to communicate with one another both fluidly and electrically.

[0014] In still further aspects of the present disclosure, a method of assembling a module of an electronic drive system comprises the steps of attaching surface mount components of a module circuit to a printed circuit board (PCB); attaching one of a diode and an insulated gate bipolar transistor (IGBT) from the module circuit to a cooling plate; securing the cooling plate to the PCB to define a cooling plate assembly; and attaching leads from one of the diode and the IGBT to the PCB.

[0015] In still further aspects of the present disclosure, an electronic drive system comprises an input module; an inverter module vertically positioned with respect to the input module; and a control module, the control module vertically positioned with respect to the inverter module,wherein the input module, the inverter module, and the control module are configured to communicate with one another both fluidly and electrically.

[0016] Various implementations described in the present disclosure can comprise additional systems, methods, features, and advantages, which may not necessarily be expressly disclosed herein but will be apparent to one of ordinary skill in the art upon examination of the following detailed description and accompanying drawings. It is intended that all such systems, methods, features, and advantages be included within the present disclosure and protected by the accompanying claims. The features and advantages of such implementations can be realized and obtained by means of the systems, methods, features particularly pointed out in the appended claims. These and other features will become more fully apparent from the following description and appended claims, or can be learned by the practice of such exemplary implementations as set forth hereinafter.BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The features and components of the following figures are illustrated to emphasize the general principles of the present disclosure. Corresponding features and components throughout the figures can be designated by matching reference characters for the sake of consistency and clarity.

[0018] Figure 1 is a typical circuit diagram for a VFD.

[0019] Figure 2 is a perspective view of a multi-axis modular electronic drive system constructed in accordance with some embodiments of the present disclosure.

[0020] Figure 3 is a sectional view, taken along line 3-3 in FIG. 2, of a multi-axis modular electronic drive system constructed in accordance with some embodiments of the present disclosure.

[0021] Figure 4 is a system diagram of a multi-axis modular electronic drive system constructed in accordance with some embodiments of the present disclosure.

[0022] Figure 5A is a schematic diagram of an electrical circuit arrangement the multi-axis modular electronic drive system constructed in accordance with some embodiments of the present disclosure.

[0023] Figure 5B is a circuit diagram of a three-phase doubler circuit that can substitute for the rectifier circuit of the multi-axis modular electronic drive system schematically illustrated in FIG. 5A.

[0024] Figure 5C is a circuit diagram of a single-phase doubler circuit that can substitute for the rectifier circuit of the multi-axis modular electronic drive system schematically illustrated in FIG 5A.

[0025] Figure 6 is a perspective view of an input module of the multi-axis modular electronic drive system illustrated in FIGs. 2 and 3.

[0026] Figure 7 is a sectional view of the input module illustrated in FIG. 6, taken along line 7-7 in FIG. 6.

[0027] Figure 8 is an enlarged sectional view of the input module illustrated in FIG. 6, taken along line 8-8 in FIG. 6.

[0028] Figure 9A is a top perspective view of an inverter module of the multi-axis modular electronic drive system illustrated in FIGs. 2 and 3.

[0029] Figure 9B is a perspective view isolating the housing of the inverter module illustrated in FIG. 9A.

[0030] Figure 9C is a perspective view isolating a printed circuit board (PCB) of the inverter module illustrated in FIG. 9A.

[0031] Figure 9D is a top perspective view of a cooling plate employed in the inverter module of FIG. 9A.

[0032] Figure 9E is a top perspective view of a subassembly comprising the PCB of FIG. 9C and the cooling plate of FIG. 9D.

[0033] Figure 10 is a bottom perspective view of the inverter module illustrated in FIG. 9A.

[0034] Figure 11 A is a partial sectional view of the inverter module illustrated in FIG. 9A, taken along line 11A-11A in FIG. 9A.

[0035] Figure 11 B is a partial sectional view of the inverter module illustrated in FIG. 9A, taken along line 11 B-11 B in FIG. 9A.

[0036] Figure 11C is a partial sectional view of the inverter module illustrated in FIG. 9A, taken along line 11C-11C in FIG. 9A.

[0037] Figure 12 is a top perspective view of a control module of the multi-axis modular electronic drive system illustrated in FIGs. 2 and 3.

[0038] Figure 13 is a sectional view of the control module illustrated in FIG. 12, taken along line 13-13 in FIG. 12.DETAILED DESCRIPTION

[0039] The present disclosure can be understood more readily by reference to the following detailed description, examples, drawings, and claims, and their previous and followingdescription. However, before the present devices, systems, and / or methods are disclosed and described, it is to be understood that this disclosure is not limited to the specific devices, systems, and / or methods disclosed unless otherwise specified, as such can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

[0040] The following description is provided as an enabling teaching of the present devices, systems, and / or methods in their best, currently known aspect. To this end, those skilled in the relevant art will recognize and appreciate that many changes can be made to the various aspects described herein, while still obtaining the beneficial results of the present disclosure. It will also be apparent that some of the desired benefits of the present disclosure can be obtained by selecting some of the features of the present disclosure without utilizing other features.Accordingly, those who work in the art will recognize that many modifications and adaptations to the present disclosure are possible and can even be desirable in certain circumstances and are a part of the present disclosure. Thus, the following description is provided as illustrative of the principles of the present disclosure and not in limitation thereof.

[0041] Reference numerals common to more than one accompanying figure identify the same component throughout the figures.

[0042] As used throughout, the singular forms “a,” “an” and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a quantity of one of a particular element can comprise two or more such elements unless the context indicates otherwise.

[0043] Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. When such a range is expressed, another aspect comprises from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about” or substantially,” it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint.

[0044] For purposes of the present disclosure, a material property or dimension measuring about X or substantially X on a particular measurement scale measures within a range between X plus an industry-standard upper tolerance for the specified measurement and X minus an industry-standard lower tolerance for the specified measurement. Because tolerances can vary between different materials, processes and between different models, the tolerance for a particular measurement of a particular component can fall within a range of tolerances.

[0045] As used herein, the terms “optional” or “optionally” mean that the subsequently described event or circumstance may or may not occur, and that the description comprises instances where said event or circumstance occurs and instances where it does not.

[0046] The word “or” as used herein means any one member of a particular list and also comprises any combination of members of that list.

[0047] To simplify the description of various elements disclosed herein, the conventions of “top,” “bottom,” “side,” “upper,” “lower,” “horizontal,” and / or “vertical” may be referenced. Unless stated otherwise, “top” describes that side of the system or component that is facing upward and “bottom” is that side of the system or component that is opposite or distal the top of the system or component and is facing downward. Unless stated otherwise, “side” describes that an end or direction of the system or component facing in horizontal direction. “Horizontal” or “horizontal orientation” describes that which is in a plane aligned with the horizon. “Vertical” or “vertical orientation” describes that which is in a plane that is angled at 90 degrees to the horizontal.

[0048] FIGs. 2 and 3 are perspective and sectional views, respectively, of a multi-axis modular electronic drive system 100 constructed in accordance with some embodiments of the present disclosure. Multi-axis modular electronic drive system 100 can comprise an input module 600 described below with regard to FIGs. 6-8, the input module 600 configured to include a rectifier circuit and a DC filter circuit, the rectifier circuit communicating with an input of the DC filter circuit, an inverter module 900 described below with regard to FIGs. 9A-11A, the inverter module 900 configured to include an inverter circuit communicating with an output of the DC filter circuit, the inverter module 900 stacked atop the input module 600, and a control module 1200 described below with regard to FIGs. 12-13, the control module 1200 stacked atop the inverter module 900. As will be described herein in greater detail, the input module 600, the inverter module 900, and the control module 1200 communicate with one another both fluidly and electrically. Additional inverter modules, such as a second inverter module 900' and a third inverter module 900", can be stacked atop one another in system 100 as shown without interrupting the fluid and electrical connectivity between the other system modules 600,900,1200. Although FIG. 2 illustrates three inverter modules 900, 900', 900", a greater or lesser number of inverter modules can be used in the system 100, depending on the power demands of a machine to be driven by the system 100. The input module 600 is provided with an AC mains connector 102 to receive AC power from an AC power source 402 (FIG. 4), and the inverter modules 900, 900', 900" are each provided with respective VFD cable connectors 104 to output power to respective motors 404, 404', 404N' (FIG. 4).

[0049] Referring to FIGs. 2-3 and 6-8, the input module 600 includes an input module housing 602 defining a cavity 604, a lower end 605, and an upper end 606, the upper end 606 defining an opening 608 (FIG. 7) of the input module housing 602. The input module 600 further includes a rectifier cooling plate 610 comprising a peripheral bearing portion 611 configured to bear against the upper end 606 of the input module housing 602, and a rectifier cooling plate hub 612 extending axially upwardly from the peripheral bearing portion 611 and terminating in a ridge 613 (FIG 8), which can in cross section define a peripheral groove 613a in which a sealing gasket 617 can be seated. The rectifier cooling plate hub 612 can define an inner wall 612a (FIGs. 7 and 8), a first opening 612b, a second opening 612c, and a spoke plate 614 projecting inwardly from the inner wall 612a, the spoke plate 614 defining an upper surface 614a (FIG. 7) and a lower surface (not shown). One or more lugs 634 can also project inwardly from the inner wall 612a, each lug 634 having a screw cavity 635 (FIG. 8) defined therein to accept a fastener (such as the inverter module mounting screw 950 discussed below with regard to FIGs. 10 and 11 A) that can be used to secure the inverter module 900 to the input module 600 once system 100 is being assembled. The peripheral bearing portion 611 can be secured to the upper end 606 of the input module housing 602 as shown with a plurality of housing attachment screws 615, although other types of fasteners can be used in place of the housing attachment screws 615. The rectifier cooling plate 610 can be composed of aluminum, zinc, or other material with good thermal conductivity properties.

[0050] Still referring to FIGs. 2-3 and 6-8, the input module 600 of the multi-axis modular electronic drive system 100 is further provided with a coolant supply assembly comprising a supply conduit 616 defining an inlet (which can comprise a supply fitting 618) through which coolant enters, as shown by arrow 620 in FIG. 2, and a supply conduit chamber 622 (FIG. 7). The supply conduit 616 extends through the first opening 612b in the hub 612 of the rectifier cooling plate 610. At least a portion of the supply conduit 616 contacts the upper surface 614a of the spoke plate 614, as best seen in FIG. 7. An input module supply nipple 624 fluidly communicates with the supply conduit chamber 622, the input module supply nipple 624 configured to direct coolant axially upwardly from the supply conduit chamber 622. The input module 600 is further provided with a coolant return assembly comprising a return conduit 626 defining a return outlet (which can comprise a return fitting 628). The return conduit 626 also defines a return conduit chamber 627 (FIG. 7). The return conduit 626 extends through the second opening 612c in the hub 612 of the rectifier cooling plate 610, and at least a portion of the return conduit 626 contacts the upper surface 614a of the spoke plate 614, as best seen in FIG. 7. An input module return nipple 632 fluidly communicates with the return conduit chamber627, the input module return nipple 632 configured to direct coolant axially downwardly from stackable return nipples positioned above the input module return nipple 632 and into the return conduit chamber 627. Coolant that has finished circulating through the system 100 exits the return conduit chamber 627 through the return outlet (return fitting) 628, as shown by arrow 630 in FIG. 2.

[0051] The overall path of coolant through the system 100 is best seen in the sectional view of FIG. 3. As discussed above, input module supply nipple 624 directs supplied coolant axially upwardly. A stackable supply nipple 916 fluidly communicates at an inlet end with the input module supply nipple 624. The upwardly directed coolant travels through at least the stackable supply nipple 916 in the first inverter module 900 en route to a coolant return tube 1210 defined within a cavity 1203 enclosed by a control module housing 1202 of the control module 1200. If additional inverter modules are used, such as the second inverter module 900' and the third inverter module 900" shown in FIG. 3, then before the supplied coolant reaches the coolant return tube 1210, it will first exit the stackable supply nipple 916 and continue its upward travel through the respective stackable supply nipples 916' and 916" of the second inverter module 900' and the third inverter module 900". Thus, the stackable supply nipples 916, 916', 916" are positioned in stacked relation to form an extended supply nipple chamber, defining a coolant supply path extending between the input module supply nipple 624 and the coolant return tube inlet end 1210a. In the example of FIG. 3, an inlet end 1210a of the coolant return tube 1210 fluidly communicates with an outlet end of the stackable supply nipple 916", and an outlet end 1210b of the coolant return tube 1210 fluidly communicates with an inlet end of a stackable return nipple, such as the stackable return nipple 918" of the third inverter module 900". Thus, coolant that enters the inlet end 1210a of the coolant return tube 1210 exits the coolant return tube 1210 through the outlet end 1210b to become returned coolant. The returned coolant begins its downward travel through the stackable return nipple 918" en route to the input module return nipple 632. In the example of FIG. 3, before the returned coolant reaches the input module return nipple 632, it will first exit the stackable return nipple 918" and continue its downward travel through the respective stackable supply nipples 918' and 918 of the second inverter module 900' and the first inverter module 900. Thus, the stackable return nipples 918,918', 918" are positioned in stacked relation to form an extended return nipple chamber, defining a coolant return path extending between the coolant return tube outlet end 1210b and the input module return nipple 632. Additional details regarding the construction of the stackable nipples 916,918 will be discussed herein with regard to FIGs. 9A-11A.

[0052] FIG. 4 is a system diagram of a modular multi-axis modular electronic drive system (such as system 100) constructed in accordance with some embodiments of the present disclosure, FIG. 4 illustrating an environment 400 in which system 100 can operate. Environment 400 includes power from an AC power source 402 being directed into the input module 600 of the system 100, as well as motors 404,404',404N respectively associated with the outputs of the stacked inverter modules 900,900',900N. FIG. 4 also demonstrates that the input module 600 can provide a uniform output voltage, such as 400V DC, to the inverter modules 900-900N regardless of the differing equipment supply voltages exemplified in input module variations 600A,600B,600C. The multi-axis modular electronic drive system 100 described herein is especially significant in its application to OEM equipment in that the system 100 provides the flexibility to be configured to support a wide range of motor types and quantities5C. For instance, process chillers come in many varieties based on the application need, and the chillers could have one or more process pumps. In some cases, the process pumps are used in independent hydraulic circuits because the customer application requires multiple cooling circuits with different temperatures, pressures, flow rates, and process fluids. In other cases, two pumps in parallel can be used in the same circuit to provide redundancy. There are also cases in which the main process pump operates at low flow and high pressure and a second pump is needed to circulate the process fluid through the heat exchangers so the refrigeration system works properly. Chillers can also have one or more variable and / or fixed speed compressors. The compressors can also vary widely in their power levels. Likewise, the number of cooling fans can vary from zero (water cooled chillers) to multiple in air cooled designs. Like the compressors, the fan power levels can vary significantly based on size.

[0053] FIG. 5A is a schematic diagram of an electrical circuit arrangement 500 in the multi-axis modular electronic drive system (such as system 100) constructed in accordance with some embodiments of the present disclosure. The electrical circuit arrangement 500 includes a rectifier circuit 502 comprising an input 502a, an output 502b, and a plurality of rectifier diodes 508, with pairs of the rectifier diodes 508 connected in series, and different pairs of rectifier diodes 508 connected in parallel with respect to one another. The rectifier circuit 502 is positioned within the input module 600 (FIG. 4) of system 100. The input 502a of the rectifier circuit 502 is configured to communicate with a three-phase AC power source 402'. The output 502b of the rectifier circuit 502 communicates with a DC filter circuit 504, the DC filter circuit 504 including a DC filter capacitor 510 and a filter inductor 642 connected in series. As best seen in FIGs. 3 and 7, the DC filter capacitor 510 and the DC filter inductor 642 are received in the cavity 604 of the input module housing 602. A DC bus 505 electrically communicates at a DCbus input 505a with an output of the DC filter circuit 504, more particularly, with an output of the DC filter capacitor 510. The filter inductor DC 642 helps to filter out transients on the DC bus 505 and to meet EMC (electromagnetic compatibility) requirements. The positioning of the DC filter inductor 642 within the cavity 604 is advantageous because filter inductors are typically quite large devices and are difficult to package in conventional PCB assemblies. The DC bus 505 also electrically communicates at DC bus outputs 505b with one or more inverter circuits 506,506',506N. Each inverter circuit 506,506',506N is positioned within a respective inverter module 900,900',900N (FIG. 4), and each inverter circuit 506,506',506N comprises a plurality 512,512',512N of insulated gate bipolar transistors (IGBTs) 513 connected to one another in the “bridge” configuration shown, namely, with pairs of the IGBTs 513 connected in series, and different pairs of IGBTs 513 connected in parallel with respect to other pairs of IGBTs 513. In a manner similar to FIG. 4, the respective outputs of the inverter circuits 506,506',506N are shown connected to the respective three-phase motors 404,404',404N.

[0054] FIGs. 5B and 5C disclose alternative voltage doubler circuits that can optionally substitute for the rectifier circuit 502 (FIG. 5A) in the input module 600 of the system 100. FIG. 5B illustrates a three-phase voltage doubler circuit 514 communicating at an input with the three-phase AC power source 402' and at an output with an input of the DC filter circuit 504, the opposite side of the DC filter circuit 504 defining an output 504a. FIG. 5B shows that the three- phase voltage doubler circuit 514 includes a plurality of diodes D1-D11. The three-phase voltage doubler circuit 514 can convert a voltage associated with the three-phase AC power source 402' to, for example, 400V DC. FIG. 5C illustrates a single-phase voltage doubler circuit 516 that can convert a voltage associated with a single-phase AC power source 402" to, for example, 400V DC. Therefore, in such embodiments, the same 400V DC input inverter modules 900,900',900N (FIG. 4) can be used independently of whether the equipment supply voltage is 220VAC / 1 / 60HZ, 208-230VAC / 30 / 60Hz, 440-480VAC / 3<D / 60Hz, or 380-415VAC / 3 / 50Hz. This means that OEM equipment can be constructed with standard motors 404,404',404N, and that the performance of those motors is completely agnostic of the supply voltage, phase, and frequency. Furthermore, the inverter modules 900,900',900N can be designed with microprocessors capable of supporting drive waveforms for both induction motors and permanent magnet AC motors through parameter changes in firmware, allowing the same inverter modules 900,900',900N to drive both induction motors and permanent magnet AC motors. FIG. 5C shows that the single-phase voltage doubler circuit 516 includes a pair of diodes D1 and D2.

[0055] Referring again to FIGs. 6-8, the electrical components of the input module 600 are now more readily understood given the above discussion of system circuitry. The input module 600 further comprises an input module printed circuit board (PCB) 638 at least partially covering the opening 608 of the input module housing 602, the input module PCB 638 and the rectifier cooling plate 610 supporting components of the rectifier circuit 502 (FIG. 5A). The input module PCB 638 further supports the DC bus 505 (FIG. 5A), the input 505a of which communicates with the DC filter capacitor 510. The input module PCB 638 defines an upper surface 638a, which can support an input module communications header 640. The upper portion of the input module communications header 640 comprises a plurality of pins that are receivable in an inverter module communications receptacle 922 (FIG. 10). In this manner, the connected communications components 640,922 can pass communication signals from between the input module 600 and an inverter module 900.

[0056] Still referring to FIGs. 6-8, the input module 600 can further comprise standoffs that allow the DC bus 505 (FIG. 5A) to be extended into one or more inverter modules 900. In particular, a first positive DC bus standoff 644 extends upwardly from the input module PCB 638, the first positive DC bus standoff 644 electrically communicating with a positive lead from the DC bus 505. A first negative DC bus standoff 646 extends upwardly from the input module PCB 638, the first negative DC bus standoff 646 electrically communicating with a negative lead from the DC bus 505. A first ground DC bus standoff 648 extends upwardly from the input module PCB 638, the first ground DC bus standoff 648 electrically communicating with a ground of the DC bus 505. As best seen in FIGs. 7 and 8, the first positive DC bus standoff 644 defines a threaded bore 645 therein, the threaded bore 645 configured to cooperate with and receive a lower male threaded end of a positive DC bus standoff from an inverter module 900.. This internal configuration of the first positive DC bus standoff 644 is substantially identical to the other two DC bus standoffs 646,648. As best seen in FIG. 7, each of the standoffs 644,646,648 can be secured to the input module PCB 638 with a self-clinching fastener 650 that encircles a lower male threaded end of the standoff. For example, in FIG. 7, the self-clinching fastener 650 surrounds the lower male threaded end 648a of the second ground DC bus standoff 948. In some embodiments of the system 100, the self-clinching fastener 650 can be an annularshaped fastener known as a PEM® fastener, made commercially available from PennEngineering®, based in Danboro, Pennsylvania, United States.

[0057] FIGs. 9A-11C illustrate the inverter module 900 of the multi-axis modular electronic drive system 100 in greater detail. The inverter module 900 includes an inverter module housing 902, the inverter module housing 902 defining an inverter module wall 904, the inverter modulewall 904 defining an inner surface 904a, an upper end 906, a lower end 908, and an opening 910. The lower end 908 of the inverter module housing 902 is configured to bear against the rectifier cooling plate 610 of the input module 600, more particularly, against the ridge 613 of the rectifier cooling plate hub 612. As best seen in FIGs. 11A-11C, the upper end 906 of the inverter module housing 902 can in cross section define a peripheral groove 906a in which a sealing gasket 907 can be seated. Referring to FIG. 9B, one or more inverter module lugs 934 can project inwardly from the inner surface 904a of the inverter module wall 904. The inverter module wall 904 can define an access aperture 905 to accommodate an assembly associated with the VFD cable connector 104 (FIGs. 2 and 3). Each inverter module lug 934 defines a screw cavity 935 (FIGs. 11 A and 11 B) in which can sit a threaded insert 936 to accept a threaded fastener that can be used to, if desired secure another inverter module 900 or a control module 1200 to the inverter module 900 once system 100 is being assembled. For example, such a threaded fastener can be an inverter module mounting screw identically constructed to the inverter mounting screw 950 (FIGs. 11 A and 11 B), or it can be a control module mounting screw 950' (FIG. 13) if the control module 1200 is to be attached. This arrangement reflects a novel stacking screw connection system, wherein an inverter module mounting screw 950 is inserted into a screw cavity 935 of an inverter module lug 934. After the inverter module mounting screw 950 is inserted into the screw cavity 935, the threaded insert 936 is heat staked into the top of the screw cavity 935, providing means for the next module to be attached inline. Also shown in FIG. 9B, respective pairs of inverter cooling plate mounting bosses 937,939 can in some embodiments project radially inwardly from the inner surface 904a of the inverter module wall 904, each pair of inverter cooling plate mounting bosses 937,939 at least partially circumferentially surrounding an associated inverter module lug 934. The inverter cooling plate mounting bosses 937,939 respectively define Plastite® screw mounting holes 937a, 939a that accommodate respective fasteners allowing attachment of an inverter cooling plate 914 in the manner described below with regard to FIGs. 9D and 10.

[0058] Referring to FIGs. 9A and 9C, the inverter module 900 further comprises an inverter module printed circuit board (PCB) 912, the inverter module PCB 912 at least partially covering the opening 910 of the inverter module housing 902 at the lower end 908. The inverter module PCB 912 is configured to communicate with the output 505b of the DC bus 505 (FIG. 5A) located in the input module 600. As best seen in FIG. 9C, the inverter module PCB 912 defines a first opening 912a, a second opening 912b, and an upper surface 912c bounded by a peripheral edge 912d. A plurality of first clearance cut-out sections 911 extend inwardly from the peripheral edge 912d. The first clearance cut-out sections 911 provide clearance for theinverter cooling plate mounting bosses 937,939 (FIG. 9B). A second clearance cut-out section 913 likewise extends inwardly from the peripheral edge 912d. The second clearance cut-out section 913 allows clearance for an end of the VFD cable connected via the VFD cable connector 104 (FIGs. 2 and 3). The inverter module PCB 912 additionally defines a plurality of DC bus standoff mounting holes 915, each of which can be plated as shown at 915a. The DC bus standoff mounting holes 915 accommodate respective inverter module DC bus standoffs 944,946,948, discussed in further detail below with regard to FIGs. 9A and 11 A. The inverter module PCB 912 further defines a plurality of inverter cooling plate mounting holes 917, each of which accommodates a threaded fastener such as an inverter cooling plate mounting screw 952 (FIGs. 9E and 11 B), which aids in securing the inverter module PCB 912 to the inverter cooling plate 914 as further discussed in detail below with regard to FIG. 11 B.

[0059] Still referring to FIGs. 9A and 9C, the upper surface 912c of the inverter module PCB 912 can support an inverter module communications header 920. The upper portion of the inverter module communications header 920 comprises a plurality of pins 920a, the lower ends of which are received in corresponding communications header mounting holes 921 formed into the inverter module PCB 912, and the upper ends of which are receivable in a communications receptacle of a module to be stacked atop the input module 600. Thus, the pins of the inverter module communications header 920 can be received in corresponding apertures located in either in the inverter module communications receptacle 922 (FIG. 10) or in the control module communications receptacle 1218 (FIG.13). This connectivity can form a column of communications headers 640, 920, 920', 920" that electrically communicate with one another, such a column exemplified in FIG. 3, allowing the associated modules to pass communication signals to and from one another.

[0060] As best seen in FIGs. 9D and 10, an inverter cooling plate 914 is attached to the lower end 908 of the inverter module housing 902 by means such as housing fasteners (screws) 949 extending through respective apertures 909a formed into lower end bosses 909 projecting radially inwardly from the lower end 908, and thence into the Plastite® screw mounting holes 937a, 939a respectively formed into the inverter cooling plate mounting bosses 937,939 (also shown in FIG. 9B) of the inverter module housing 902. The inverter cooling plate 914 defines a first opening 914a axially aligned with the first opening 912a in the inverter module PCB 912, and further defines a second opening 914b axially aligned with the second opening 912b in the inverter module PCB 912. The inverter module 900 further comprises a stackable supply nipple 916 (FIG. 9A) defining an inlet end 916a (not shown), an outlet end 916b, and a supply nipple chamber (not shown) extending between the inlet end 916a and the outlet end 916b. Thestackable supply nipple 916 is supported by the inverter cooling plate 914 such that the stackable supply nipple 916 extends upwardly through the first opening 912a in the inverter module PCB 912, and the supply nipple chamber is axially aligned with the first opening 914a in the inverter cooling plate 914. Similarly, the inverter module 900 further comprises a stackable return nipple 918 defining an inlet end 918a, an outlet end 918b (not shown), and a return nipple chamber extending between the inlet end 918a and the outlet end 918b. The stackable return nipple 918 is supported by the inverter cooling plate 914 such that the stackable return nipple 918 extends upwardly through the second opening 912b in the inverter module PCB 912, and the return nipple chamber is axially aligned with the second opening 914b in the inverter cooling plate 914. Both the stackable supply nipple 916 and the stackable return nipple 918 can be provided with respective integrated O-rings 923,925 to respectively connect the coolant supply line and the coolant return line from one inverter module to the next as each inverter module is added. As best seen in FIG. 9D, a stackable supply nipple mounting boss 940 and a stackable return nipple mounting boss 941 are disposed on the upper surface 914c of the inverter cooling plate 914. The bosses 940,941 can define respective apertures 940a, 941a that are respectively axially aligned with respect to the first and second openings 914a, 914b defined by the inverter cooling plate 914.

[0061] Still referring to FIG. 9D, the inverter cooling plate 914 can, in some embodiments, be a single substantially X-shaped member defining a geometric center C from which can outwardly extend a four arms 927, each arm 927 terminating in a first forked end 929 and a second forked end 930, the forked ends 929,930 joined by a boss clearance cut-out section 932, Each boss clearance cut-out section 932 extends inwardly from the forked ends 929,930 toward the center C, and is configured to provide clearance with respect to the lower end boss 909 (discussed above with regard to FIG. 1010) when the inverter cooling plate 914 is attached to the inverter module housing 902. The forked ends 929,930 respectively define inverter cooling plate mounting holes 929a, 930a that each accommodate the housing fasteners (screws) 949 mentioned above. Each such fastener 949 aids in securing the inverter cooling plate 914 directly to the inverter module housing 902 by extending through the apertures 909a of the lower end bosses 909 and into the Plastite® screw mounting holes 937a, 939a respectively formed into the inverter cooling plate mounting bosses 937,939 (also shown in FIG. 9B), as best seen in FIGs. 10 and 11C. Extending upwardly from the upper surface 914c of the inverter cooling plate 914 are a plurality of inverter PCB mounting bosses 942, which in the illustrated example are positioned at each of the arms 927. In some embodiments, each inverter PCB mounting boss 942 can define boss openings 942a, each opening 942a being preferably axially aligned withthe inverter cooling plate mounting holes 917 (FIG. 9C) in the inverter module PCB 912, and each boss opening 942a configured to accommodate the inverter cooling plate mounting screw 952 (FIGs. 9E and 11 B). Finally, the inverter cooling plate 914 defines a plurality of IGBT mounting holes 943, each IGBT mounting hole 943 configured to receive an IGBT mounting screw 954, discussed below with regard to FIGs. 11 A and 11 C. Although the foregoing description of the inverter cooling plate 914 has been set forth with regard to a substantially X- shaped member, the disclosed shape of the inverter cooling plate 914 is for illustrative purposes only and is not intended to be limiting. Further, although FIG. 9D illustrates six IGBT mounting holes 943, the inverter cooling plate 914 can define a greater or lesser number of such holes 943, depending upon design requirements.

[0062] FIG. 9E is a top perspective view of a subassembly 947 further illustrating the abovedescribed connections between the inverter module PCB 912 and the inverter cooling plate 914. FIG. 9E also illustrates the inverter module communications header 920 mounted to the upper surface 912c of the inverter module PCB 912, as well as the mounting of a stackable supply nipple 916 to the stackable supply nipple mounting boss 940, and of a stackable return nipple 918 to the stackable return nipple mounting boss 941 (FIG. 9D).

[0063] Referring to FIGs. 9A and 11 A, the inverter module 900 can further comprise standoffs that allow the DC bus 505 (FIG. 5A) to be extended into additional inverter modules 900. In particular, a second positive DC bus standoff 944 extends upwardly from the inverter module PCB 912, the second positive DC bus standoff 944 configured to electrically communicate at a lower male threaded end 944a with the first positive DC bus standoff 644 (FIGS. 6 and 8) of the input module 600 and, at an upper end 944b, with another inverter module positive DC bus standoff. The second positive DC bus standoff 944 defines a threaded bore 945 therein, the threaded bore 945 configured to cooperate with and receive a lower male threaded end of a positive DC bus standoff from another inverter module 900N (FIG. 4), if it is necessary to include another inverter module 900N in the multi-axis modular electronic drive system 100. The configuration of threaded bore 945 can also be used for standoffs 946,948, described herein. In particular, a second negative DC bus standoff 946 extends upwardly from the inverter module PCB 912, the second negative DC bus standoff 946 configured to electrically communicate at a lower male threaded end 946a with the first negative DC bus standoff 646 of the input module 600 and, at an upper end 946b, with another inverter module negative DC bus standoff. A second ground DC bus standoff 948 extends upwardly from the inverter module PCB 912, the second ground DC bus standoff 948 configured to electrically communicate at a lower male threaded end 948a with the first ground DC bus standoff 648 of the input module 600 and, at anupper end 948b, with another inverter module ground DC bus standoff. In some embodiments, the inverter module PCB 912 can define plated through-holes, through which the lower male threaded ends 944a, 946a, 948a extend, and unlike with the input module PCB 638 (FIGs. 6-8), self-clenching fasteners are not used to attach the DC bus standoffs 944,946,948 to the inverter module PCB 912. In such instances, the self-clinching fasteners 650 (FIG. 7) can be used only for the input module PCB 638.

[0064] Referring to FIGs. 8, 10, 11A, and 11C, additional hardware connections of certain components of the input module 600 and of the inverter module 900 will now be described to the extent that they have not been described above.

[0065] FIG. 8 illustrates various connections of components in the input module 600 and exemplifies the heat sinking arrangements and characteristics of system 100. A rectifier diode 508 (introduced in FIG. 5A) is shown being sandwiched between the input module PCB 638 and the spoke plate 614 which, as discussed above, is an extension of the rectifier cooling plate 610. Thus, during operation, the rectifier diode 508 can transfer the heat it generates through the spoke plate 614 of the rectifier cooling plate 610, which transfers the heat into the returned coolant flowing into the return conduit 626 from the input module return nipple 632. Thus, the rectifier cooling plate 610 (including the spoke plate 614) provides direct conductive cooling to power electronic components and then convectively transfers the heat into the coolant. This cooling method provides much higher cooling efficiency than air cooling the electronics and enables use of lower cost electronic components that have higher on resistances than those required when air cooling the electronics. In some embodiments of system 100, the rectifier diode 508 and the spoke plate 614 can be mechanically secured to one another such as with diode mounting screws 639a, 639b. FIG. 8 also illustrates the rectifier cooling plate 610 being attached to the input module PCB 638 with an input module PCB mounting screw 652, which can be received in a threaded bore formed into the peripheral bearing portion 611 of the rectifier cooling plate 610.

[0066] FIGs. 11A and 11C illustrate additional hardware connections of certain components of the inverter module 900. The inverter cooling plate mounting screw 952 can mechanically secure the inverter cooling plate 914 to the inverter module PCB 912. FIGs. 11A and 11C also show an IGBT mounting screw 954 securing an IGBT 513 to the inverter cooling plate 914. As shown in those figures, the orientation of the IGBT mounting screw 954 can be either right-side up or upside-down, depending on the configuration of the mounting means for the IGBTs 513. Heat can therefore be convectively transferred away from the IGBT 513 in a manner similar to that described above with regard to the rectifier diode 508 (FIG. 8).

[0067] With the various hardware connections described with regard to both the input module 600 and the inverter module 900, a method of assembling those modules can now be more readily described with reference to a module circuit that, depending upon the type of module, can comprise, on one hand, either a rectifier circuit 502 (FIG. 5A) or a voltage doubler circuit 514,516 (FIGs. 5B and 5C) or, on the other hand, an inverter circuit 506 (FIG. 5A).

[0068] As to the input module 600, the module circuit is either the rectifier circuit 502 or a voltage doubler circuit 514,516. Assembly of the input module 600 is here discussed using the rectifier circuit 502 as an example. First, surface mount components of the rectifier circuit 502 are attached to the input module PCB 638 (FIGs. 6-8). Then one or more rectifier diodes 508 (FIG. 8) are attached to the rectifier cooling plate 610 (FIGs. 6-8), an exemplary type of such attachment having been described above with regard to FIG. 8. Heat sink compound can additionally be used to effect this attachment. Other components of the rectifier circuit 502 that require cooling when in operation can also be attached to the rectifier cooling plate 610 in like manner. Next, the rectifier cooling plate 610 can be secured to the input module PCB 638, such as by the input module PCB mounting screw 652 (FIG. 8), to define a rectifier cooling plate assembly. Then leads from each rectifier diode 508 are attached to the input module PCB 638. The rectifier cooling plate assembly is then inverted, whereafter at least one DC filter capacitor 510 and at least one DC filter inductor 642 are attached to the input module PCB 638.

[0069] As to the inverter module 900, the module circuit is the inverter circuit 506. To assemble the inverter module 900, surface mount components of the inverter circuit 506 are attached to the inverter module PCB 912 (FIG. 9C). Then one or more IGBTs 513 (FIGs. 11A- 11C) are attached to the inverter cooling plate 914, an exemplary type of such attachment having been described above with regard to FIGs. 11 A and 11 C. Heat sink compound can additionally be used to effect this attachment. Other components of the inverter circuit 506 that require cooling when in operation can also be attached to the inverter cooling plate 914 in like manner. Next, the inverter cooling plate 914 can be secured to the inverter module PCB 912, such as by one or more of the inverter cooling plate mounting screws 952 (FIGs. 9E and 11 A- 11C). Then leads from each IGBT 513 can be attached to the inverter module PCB 912.

[0070] It is thus seen that the methods of assembling the input module 600 and the inverter module 900 have the following steps in common: (a) attaching surface mount components of a module circuit to a PCB; (b) attaching one of a diode and an IGBT from the module circuit to a cooling plate; (c) securing the cooling plate to the PCB to define a cooling plate assembly; and (d) attaching leads from one of the diode and the IGBT to the PCB.

[0071] FIGs. 12 and 13 are top perspective and sectional views, respectively, of the control module 1200 of the multi-axis modular electronic drive system 100. Control module 1200 provides several important functions for the system 100. First, it completes the system stack and hermetically seals the entire system to IP67 (ingress protection) standards. Second, as discussed above with regard to FIG. 3, the control module 1200 incorporates the coolant return tube 1210 that connects the coolant supply and stackable return nipples 916,918 from the inverter modules 900, 900', 900" to complete the coolant circuit. Third, the control module 1200 integrates all the low voltage DC power supplies required for supporting the sensors and controls on the equipment to eliminate the need for standalone DC power supplies. Finally, the control module 1200 functions as the control and communication center for the system 100 so that the system 100 can communicate with other modules and controllers used on the equipment.

[0072] The control module 1200 can comprise a control module housing 1202, the control module housing 1202 defining an upper end 1204, a lower end 1206, and a control module wall 1208 extending between the upper end 1204 and the lower end 1206, the lower end 1206 defining a lower opening 1207. The upper end 1204 can in cross section define a peripheral groove 1204a in which a sealing gasket 1205 can be seated. A cover 1211 can be received on the upper end 1204, and can be secured to the upper end 1204 in any suitable manner that provides desired sealing capabilities. For instance, as best seen in FIG. 12, the cover 1211 can be secured to the upper end 1204 with one or more attachment screws 1213 seated in regions 1211 b,c,d that can be recessed with respect to a top surface 1211a of cover 1211. Referring to FIG. 13, one or more controller cooling plate mounting bosses 1212 can project inwardly from the control module wall 1208, and each controller cooling plate mounting boss 1212 can be constructed substantially identically to either of the inverter cooling plate mounting bosses 937,939 (FIG. 9B) such that each controller cooling plate mounting boss 1212 has an aperture (not shown) to accept a control housing fastener (screw) 949', which in some embodiments can be constructed identically to any of the housing fasteners 949 described above with regard to FIGs. 9D and 10. In this manner, a control module cooling plate 914' (which can be constructed substantially identically to the inverter cooling plate 914 of FIG. 10) can be secured to the control module housing 1202. Also, as shown in FIG. 13, bosses 1214 can project inwardly from the lower end 1206 of the control module housing 1202, the bosses 1214 each defining an aperture 1214a therethrough. Each aperture 1214a axially aligns with a screw cavity (not shown) of a corresponding control module mounting lug, which is not shown but which can be constructed substantially identically to any of the inverter module lugs 934 discussed above withregard to FIG. 9B. With such a construction, a control module mounting screw 950' can extend through not only the screw cavity of the control module mounting lug, but also into a threaded insert disposed within the screw cavity 635 of the lug 634 (FIGs 11 A and 11 B) of an inverter module 900 positioned immediately beneath the control module 1200. Though such threaded inserts are not illustrated for the input module 600, they can be constructed substantially identically to the threaded inserts 936 for the inverter module 900, to be described herein with regard to FIG. 11A. In this manner the control module 1200 can be secured to inverter module 900 positioned beneath the control module. In other embodiments, a Plastite® screw can substitute for each of the control module mounting screws 950', Plastite® screws being commercially available from Research Engineering & Manufacturing Inc. of Middletown, Rhode Island. The use of such screws dispenses with the need to use threaded inserts in the screw cavities of the control module lugs.

[0073] Now referring to FIGs. 12-13, a control module printed circuit board (PCB) 1216 at least partially covers the lower opening 1207 of the control module housing 1202 at the lower end 1206. The control module housing 1202, the cover 1211 , the control module PCB 1216 together define the cavity 1203 (also discussed with regard to FIG. 3) of the control module 1200. The control module PCB 1216 defines an opening 1216a. The inlet end 1210a of the coolant return tube 1210 is configured to fluidly communicate with an outlet end of a stackable supply nipple (such as stackable supply nipple 916" in FIG. 3) positioned beneath the coolant return tube 1210. The outlet end 1210b of the coolant return tube 1210 is configured to fluidly communicate with an inlet end of a stackable return nipple (such as stackable return nipple 918" in FIG. 3) positioned beneath the coolant return tube 1210. The control module cooling plate 914' defines a first opening 1209a that defines the inlet end 1210a of the coolant return tube 1210. Similarly, the control module cooling plate 914' further defines a second opening 1209b that defines the outlet end 1210b of the coolant return tube 1210. Additionally, a plurality of mounting screws (not shown) can be used to further secure further the control module PCB 1216 to the control module cooling plate 914', and in some embodiments, such mounting screws can be constructed substantially identically to the inverter cooling plate mounting screw 952 (FIGs. 9E and 11 B).

[0074] Again referring to FIGs. 12 and 13, the control module 1200 includes signal communication components that enable communication of signals among the modules of the system 100, and communication of signals from the system 100 to external electrical elements. For example, a control module communications receptacle 1218 can be attached to an underside of the control module PCB 1216. The control module communications receptacle1218 defines a plurality of sockets to receive, and electrically communicate with, corresponding pins of an inverter module communications header, such as the inverter module communications header 920 discussed with regard to FIGs. 9A-11C. The control module 1200 can also include a communications connector 1220 that electrically communicates with the control module PCB 1216. The communications connector 1220 can accommodate a cable connector from external device, such as a controller, to allow exchange of signals between the system 100 and the external device. The communications connector 1220 can be constructed as a male connector bearing a plurality of connection pins 1222. The cover 1211 can define an opening 1221 through which the communications connector at least partially protrudes to maximize ease of access. FIG. 13 also illustrates screws 1244, each of which connects to a respective upper end of one of the inverter module DC bus standoffs 944,946,948 (FIGs. 9A and 11 A) to complete the electrical connection between the inverter module DC bus standoffs 944,946,948 and the control module PCB 1216. Although the view of FIG. 13 shows only two screws 1244, it will be understood that the control module 1200 includes three such screws 1244.

[0075] Although several aspects have been disclosed in the foregoing specification, it is understood by those skilled in the art that many modifications and other aspects will come to mind to which this disclosure pertains, having the benefit of the teaching presented in the foregoing description and associated drawings. For example, the overall multi-axis electronic drive system 100 could be rectangular in shape vs round. The module housings could be die cast aluminum vs plastic. The fluid supply nipples could be machined vs. roll formed from tubing as shown. The input module could incorporate supporting circuitry such as phase monitoring and under / over voltage protection. The input module circuit could also include an electromagnetic capability (EMC) filter circuit. Likewise, the inverter modules could incorporate supporting circuits such as but not limited to line reactors for EMC filtering, safe torque off circuitry, etc. It is thus understood that the disclosure is not limited to the specific aspects disclosed hereinabove, and that many modifications and other aspects are intended to be included within the scope of any claims that can recite the disclosed subject matter.

[0076] One should note that conditional language, such as, among others, "can," "could," "might," or "may," unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain aspects include, while other aspects do not include, certain features, elements and / or steps. Thus, such conditional language is not generally intended to imply that features, elements and / or steps are in any way required for one or more particular aspects or that one or more particular aspects necessarilycomprise logic for deciding, with or without user input or prompting, whether these features, elements and / or steps are included or are to be performed in any particular aspect.

[0077] It should be emphasized that the above-described aspects are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the present disclosure. Any process descriptions or blocks in flow diagrams should be understood as representing modules, segments, or portions of code which comprise one or more executable instructions for implementing specific logical functions or steps in the process, and alternate implementations are included in which functions may not be included or executed at all, can be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present disclosure. Many variations and modifications can be made to the above-described aspect(s) without departing substantially from the spirit and principles of the present disclosure. Further, the scope of the present disclosure is intended to cover any and all combinations and sub-combinations of all elements, features, and aspects discussed above. All such modifications and variations are intended to be included herein within the scope of the present disclosure, and all possible claims to individual aspects or combinations of elements or steps are intended to be supported by the present disclosure.

Claims

CLAIMSThat which is claimed is:

1. An input module for an electronic drive system, the input module comprising: an input module housing, the input module housing defining a cavity and an upper end, the upper end defining an opening of the input module housing; a rectifier cooling plate received upon the upper end of the input module housing, the rectifier cooling plate comprising a peripheral bearing portion configured to bear against the upper end of the input module housing, a hub extending axially upwardly from the peripheral bearing portion and terminating in a ridge, the hub defining an inner wall, a first opening, a second opening, and a spoke plate projecting inwardly from the inner wall, the spoke plate defining an upper surface and a lower surface; an input module printed circuit board (PCB) at least partially covering the opening of the input module housing, the input module PCB and the rectifier cooling plate supporting a rectifier circuit, the rectifier circuit comprising an input and an output, the input of the rectifier circuit configured to communicate with at least one of a single-phase alternating current (AC) power source and a three-phase AC power source, and the output of the rectifier circuit communicating with a direct current (DC) filter circuit, the DC filter circuit comprising a filter capacitor and a filter inductor connected in series, the filter capacitor and the filter inductor received in the cavity of the input module housing, wherein the input module PCB further supports a DC bus communicating with an output of the DC filter circuit; a coolant supply assembly comprising a supply conduit defining an inlet and a supply conduit chamber, the supply conduit extending through the first opening in the hub of the rectifier cooling plate, at least a portion of the supply conduit contacting the upper surface of the spoke plate, and an input module supply nipple fluidly communicating with the supply conduit chamber, the input module supply nipple configured to direct coolant axially upwardly from the supply conduit chamber; anda coolant return assembly comprising a return conduit defining an outlet and a return conduit chamber, the return conduit extending through the second opening in the hub of the rectifier cooling plate, at least a portion of the return conduit contacting the upper surface of the spoke plate, and an input module return nipple fluidly communicating with the return conduit chamber, the input module return nipple configured to direct coolant axially downwardly into the return conduit chamber.

2. The input module of claim 1 wherein the rectifier circuit comprises a plurality of rectifier diodes, and wherein a rectifier diode in the plurality of rectifier diodes is secured to the spoke plate with a diode mounting screw.

3. The input module of claim 1 , further comprising: a positive DC bus standoff extending upwardly from the input module PCB, the positive DC bus standoff electrically communicating with a positive lead from the DC bus; a negative DC bus standoff extending upwardly from the input module PCB, the negative DC bus standoff electrically communicating with a negative lead from the DC bus; and a ground DC bus standoff extending upwardly from the input module PCB, the ground DC bus standoff electrically communicating with a ground of the DC bus.

4. The input module of claim 1 , further comprising a stackable communications header mounted to the input module PCB, the stackable communications header comprising a plurality of pins configured to be received in corresponding apertures in an inverter module communications receptacle.

5. An inverter module for an electronic drive system, the inverter module comprising: an inverter module housing, the inverter module housing defining an inverter module wall, the inverter module wall defining an upper end, a lower end, and an opening, the lower end configured to bear against an inverter cooling plate of an input module; an inverter module printed circuit board (PCB), the inverter module PCB at least partially covering the opening of the inverter module housing, the inverter module PCBconfigured to communicate with an output of a DC bus located in the input module, the inverter module PCB defining a first opening and a second opening; an inverter cooling plate attached to the lower end of the inverter module housing, the inverter cooling plate defining a first opening axially aligned with the first opening in the inverter module PCB, the inverter cooling plate further defining a second opening axially aligned with the second opening in the inverter module PCB; a stackable supply nipple defining an inlet end, an outlet end, and a supply nipple chamber extending between the inlet end and the outlet end, wherein the stackable supply nipple is supported by the inverter cooling plate such that the stackable supply nipple extends upwardly through the first opening in the inverter module PCB and the supply nipple chamber is axially aligned with the first opening in the inverter cooling plate; and a stackable return nipple defining an inlet end, an outlet end, and a return nipple chamber extending between the inlet end and the outlet end, wherein the stackable return nipple is supported by the inverter cooling plate such that the stackable return nipple extends upwardly through the second opening in the inverter module PCB and the return nipple chamber is axially aligned with the second opening in the inverter cooling plate.

6. The inverter module of claim 5, wherein the stackable supply nipple is a first stackable supply nipple and the stackable return nipple is a first stackable return nipple, wherein the inlet end of the first stackable supply nipple is configured to fluidly communicate with at least one of an input module supply nipple and an outlet end of a third stackable supply nipple positioned below the first stackable supply nipple, wherein the outlet end of the first stackable supply nipple is configured to fluidly communicate with at least one of an inlet end of a coolant return tube and an inlet end of a second stackable supply nipple positioned above the first stackable supply nipple and, wherein the inlet end of the first stackable return nipple is configured to fluidly communicate with at least one of an outlet end of a coolant return tube and an outlet end of a second stackable return nipple positioned above the first stackable return nipple, andwherein the outlet end of the first stackable return nipple is configured to fluidly communicate with at least one of an inlet end of a second stackable return nipple positioned beneath the first stackable return nipple and an input module return nipple.

7. The inverter module of claim 5, wherein the inverter module wall defines an inner surface, and wherein the inverter module further comprises: a lug projecting inwardly from the inner surface, the lug defining a screw cavity; and a threaded insert seated within the screw cavity, the threaded insert configured to receive a mounting screw from one of another inverter module and a control module.

8. A control module for an electronic drive system, the control module comprising: a control module housing, the control module housing defining an upper end, a lower end, and a control module wall extending between the upper end and the lower end, the lower end defining a lower opening; a control module printed circuit board (PCB), the control module PCB at least partially covering the lower opening of the control module housing, the control module PCB defining an opening; a coolant return tube defining an inlet and an outlet, the inlet configured to fluidly communicate with an outlet end of a stackable supply nipple positioned beneath the coolant return tube, the outlet configured to fluidly communicate with an inlet end of a stackable return nipple positioned beneath the coolant return tube; and a control module cooling plate attached to the lower end of the control module housing, wherein the control module cooling plate defines a first opening, the first opening of the control module cooling plate defining the inlet of the coolant return tube, and the control module cooling plate further defines a second opening, the second opening of the control module cooling plate defining the outlet of the coolant return tube.

9. The control module of claim 8, further comprising a communications connector, the communications connector electrically communicating with the control module PCB.

10. The control module of claim 9, further comprising a cover received on the upper end of the control module housing, the cover defining an opening configured to accommodate the communications connector.

11. An electronic drive system, comprising: the input module of claim 1 ; the inverter module of claim 5, the inverter module stacked atop the input module; and the control module of claim 8, the control module stacked atop the inverter module; wherein the input module, the inverter module, and the control module communicate with one another both fluidly and electrically.

12. The electronic drive system of claim 11 , wherein the inverter module is a first inverter module, and further comprising a second inverter module stacked atop the first inverter module, wherein the control module is stacked atop the second inverter module, wherein the second inverter module is constructed substantially identically to the first inverter module, and wherein the input module, the first inverter module, the second inverter module, and the control module communicate with one another both fluidly and electrically.

13. The electronic drive system of claim 11 , wherein the inverter module is a first inverter module, and further comprising: a second inverter module stacked atop the first inverter module; and a third inverter module stacked atop the second inverter module, wherein the control module is stacked atop the third inverter module, wherein the second inverter module and the third inverter module are both constructed substantially identically to the first inverter module, and wherein the input module, the first inverter module, the second inverter module, the third inverter module, and the control module are configured to communicate with one another both fluidly and electrically.

14. The electronic drive system of claim 11 , wherein the input module further comprises a first positive DC bus standoff extending upwardly from the input module PCB, the first positive DC bus standoff electrically communicating with a positive lead from the DC bus, a first negative DC bus standoff extending upwardly from the input module PCB, the first negative DC bus standoff electrically communicating with a negative lead from the DC bus, and a first ground DC bus standoff extending upwardly from the input module PCB, the first ground DC bus standoff electrically communicating with a ground of the DC bus, and the inverter module further comprises a second positive DC bus standoff extending upwardly from the inverter module PCB, the second positive DC bus standoff electrically communicating with the first positive DC bus standoff of the input module, a second negative DC bus standoff extending upwardly from the inverter module PCB, the second negative DC bus standoff electrically communicating with the first negative DC bus standoff of the input module, and a second ground DC bus standoff extending upwardly from the inverter module PCB, the second ground DC bus standoff electrically communicating with the first ground DC bus standoff of the input module.

15. The electronic drive system of claim 14, wherein each of the DC bus standoffs in the input module is attached to the input module PCB with a self-clinching fastener.

16. A method of assembling a module of an electronic drive system, comprising the steps of: attaching surface mount components of a module circuit to a printed circuit board (PCB); attaching one of a diode and an insulated gate bipolar transistor (IGBT) from the module circuit to a cooling plate; securing the cooling plate to the PCB to define a cooling plate assembly; and attaching leads from one of the diode and the IGBT to the PCB.

17. The method of claim 16, wherein the module circuit is a rectifier circuit, wherein the diode is a rectifier diode, and further comprising the steps of: inverting the cooling plate assembly; and attaching at least one direct current (DC) filter capacitor and at least one DC filter inductor to the PCB.

18. The method of claim 16, further comprising the step of attaching to the cooling plate any additional components of the module circuit that require cooling when in operation.

19. An electronic drive system, comprising: an input module; an inverter module vertically positioned with respect to the input module; and a control module vertically positioned with respect to the inverter module; wherein the input module, the inverter module, and the control module are configured to communicate with one another both fluidly and electrically.

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