High voltage cooling assembly system

Abstract

The abstract pertains to a cooling assembly designed for use in mining and construction machinery. The assembly includes a fan, a fan motor mechanically connected to the fan to facilitate its rotation, and a motor drive unit electrically connected to the fan motor to provide the necessary power. The assembly also features a discharge circuit assembly, electrically connected to the motor drive unit, capable of discharging residual high voltages. The discharge circuit assembly comprises a discharge circuit. The cooling assembly also includes a first and second radiator, stacked together. The first radiator is designed to allow air to be sucked through the second radiator, and the second radiator is designed to allow air to be sucked through the fan.

Description

1137271HIGH VOLTAGE COOLING ASSEMBLY SYSTEMTechnical field

[0001] The technology pertains to the field of thermal management systems, specifically those designed for heavy machinery such as electric mining and / or construction machines. It involves the use of cooling assemblies, fans, motors, radiators, and discharge circuits to manage and dissipate heat generated by the systems of the mining and / or construction machines.Background art

[0002] In the realm of cooling systems for large machinery, such as mining equipment, the need for efficient heat dissipation is paramount. Traditionally, high power fans have been employed to generate sufficient airflow for heat dissipation from large radiators. These fans, due to their high power requirement, are typically driven by hydraulic motors, which in turn are powered by hydraulic pumps attached to a prime mover. This setup, while effective, presents several challenges.

[0003] Firstly, the hydraulic components, including the pump and motor, occupy significant space within the machine. This is particularly problematic in scenarios where space is at a premium, such as in compact mining equipment. The prime movers, which are necessary for driving the hydraulic pump, are often either too weak or too large to be practical for a direct drive fan solution.

[0004] Secondly, when radiators are stacked in front of each other to save space, the requirement for airflow increases even further. This is due to the increased resistance to airflow when the radiators are arranged in this manner. The increased airflow requirement necessitates even more powerful fans, further exacerbating the power and space challenges.

[0005] In addition to the cooling system, high voltage electric machines present their own set of challenges. These machines typically require discharge circuits to prevent residual high voltages from posing a risk to workers in hazardous1137272 situations. These circuits are usually designed to actively discharge on X, Y positive, and Y negative, to ensure that all capacitors are sufficiently discharged. However, these circuits are often bulky and occupy valuable space within the high voltage system.

[0006] Furthermore, existing solutions where radiators are stacked in parallel also present issues. Such configurations require separate air channels, fan shrouds, fans, motors, and pumps, all of which take up additional space. This is particularly problematic in applications where space is at a premium.

[0007] In summary, the prior art presents several challenges, including high power requirements for fans, increased airflow requirements for stacked radiators, the need for bulky discharge circuits, and excessive space consumption by existing radiator configurations. These challenges present significant obstacles to the development of efficient and compact cooling systems for large machinery.Summary of invention

[0008] An object of the present invention is to eliminate or at least mitigate the above mentioned problems of prior art. Thus, an object of the present invention is to provide a cooling assembly with reduced space and weight, reduced upfront cost, and reduced maintenance costs.

[0009] According to a first aspect of the disclosure, a cooling assembly for an electric mining machine is provided. The assembly comprises a fan, a fan motor mechanically connected to the fan and configured to rotate the fan, a motor drive unit electrically connected to the fan motor and configured to provide electrical power to drive the fan motor, a discharge circuit assembly electrically connected to the motor drive unit and adapted to discharge residual high voltages in the cooling assembly, a discharge circuit assembly electrically connected to the motor drive unit and adapted to discharge residual high voltages in the cooling assembly, wherein the discharge circuit assembly comprises a discharge circuit, an X capacitor provided between a positive de bus and a negative de bus, a first Y capacitor provided between the positive de bus and earth, and a second Y1137273 capacitor provided between the negative de bus and earth, and wherein the discharge circuit is provided between the positive de bus and earth; a first radiator, and a second radiator stacked with the first radiator. The first radiator is designed to allow air to be sucked through the second radiator, and the second radiator is designed to allow air to be sucked through the fan. This configuration ensures efficient cooling of both electric and hydraulic systems in confined spaces, enhancing the operational reliability of electric mining machines.

[0010] Optionally in some examples, the discharge circuit assembly is adapted to discharge the second Y capacitor through a discharge circuit on the opposite pole of a positive de bus and the negative de bus.

[0011] Optionally in some examples, the discharge circuit, preferably a resistor and a switch provided in series, is provided between the positive de bus and earth, creating a discharge current path during discharge. This design ensures that residual high voltages are effectively neutralized, preventing potential damage to the system and enhancing overall safety.

[0012] Optionally in some examples, the discharge assembly, in conjunction with the motor drive unit, is adapted to discharge two Y-poles and one X-pole.

[0013] Optionally in some examples, the discharge circuit assembly is used in conjunction with a switch-mode converter with active X discharge capabilities.

[0014] Optionally in some examples, the fan has high pressure and high airflow capability. This specification ensures that the cooling assembly can effectively manage the thermal loads of the electric and hydraulic systems, even under demanding operational conditions, thereby maintaining optimal performance.

[0015] Optionally in some examples, the fan motor is a high voltage motor, preferably a motor adapted to be supplied by a voltage above 60 volts. This adaptation allows the fan motor to achieve the necessary high pressure and high airflow rates for effective cooling, ensuring that the system remains within safe operating temperatures.1137274

[0016] Optionally in some examples, the motor drive unit is in the form of a three-phase inverter.

[0017] Optionally in some examples, the motor drive unit is in the form of a three-phase inverter. This configuration provides efficient and stable electrical power to the fan motor, ensuring consistent performance and reliability of the cooling assembly.

[0018] Optionally in some examples, the first radiator and the second radiator dissipate heat from electronic and / or hydraulic components of a system of an electric mining machine. This dual-radiator setup enhances the cooling efficiency by allowing sequential heat dissipation, thereby improving the overall thermal management of the system.

[0019] Optionally in some examples, a cooling medium for cooling the mining and / or construction machine comprises at least on of liquid to liquid or air to liquid heat exchanging devices.

[0020] According to a second aspect of the invention, a method for cooling electric and hydraulic systems of an electric mining machine with a cooling assembly is provided, the method comprises the following steps: bringing a fan to rotate by means of a fan motor powered by a motor drive unit, bringing air to flow through a first radiator by means of the fan, bringing the air flowing through the first radiator to flow through a second radiator by means of the fan, bringing the air flowing through the second radiator to flow through the fan, and discharging the cooling assembly by means of a discharge circuit assembly, comprising discharging X and Y capacitors of discharge circuit assembly by: discharging an X capacitor through an active X discharge of discharge circuit assembly, discharging a first Y capacitor through said discharge circuit on the same pole, and discharging a second Y capacitor through said discharge circuit on the opposite pole, through the active X discharge of the discharge circuit assembly. This method ensures a systematic and efficient cooling process, maintaining the operational integrity of the electric and hydraulic systems in the mining machine.1137275Brief description of drawings

[0021] The invention is now described, by way of example, with reference to the accompanying drawings, in which:Figure 1a is a perspective view of a cooling assembly showing a first radiator and a second radiator.Figure 1b is a perspective view of the cooling assembly showing a fan and a fan motor.Figure 2a is a front view of the cooling assembly showing the fan, and the fan motor.Figure 2b is a side view of the cooling assembly.Figure 2c is a top view of the cooling assembly.Figure 3 is a sectional view of the cooling assembly showing cooling assembly, fan, fan motor, first radiator, and second radiator, and the air flow therethrough.Figure 4 is a block diagram of the fan motor, a motor drive unit, and a discharge circuit.Figure 5 is a diagram of a one-pole discharge circuit powering the fan showing cooling assembly and discharge circuit.Figure 6 is a diagram of a motor drive unit in the form of an inverter.Figure 7 shows the air flow through the cooling assembly.Description of embodiments

[0022] In the following, a detailed description of a cooling assembly and a method for cooling systems of a mining machine with a cooling assembly will be given.

[0023] The detailed description set forth below provides information and examples of the disclosed technology with sufficient detail to enable those skilled in the art to practice the disclosure.1137276

[0024] Figure 1a provides a perspective view of a cooling assembly 1 , illustrating its overall structure and the arrangement of key components, specifically highlighting a first radiator 40 and a second radiator 30. The perspective view allows for a clear visualization of the spatial relationship between these components, emphasizing the stacked configuration that contributes to the assembly's compact design and space-saving advantages, particularly beneficial in mining and construction machinery where space constraints are common.

[0025] The cooling assembly 1 is designed for cooling electric and hydraulic systems, particularly in mining and construction machines. This assembly offers a space-saving solution by allowing radiators to be effectively stacked in series, which is particularly beneficial in confined areas. Additionally, the cooling assembly 1 is engineered for high pressure and high airflow capabilities, ensuring efficient cooling of the stacked radiators even with increased air resistance. The cooling assembly 1 includes several key components: a fan, a fan motor, a motor drive unit, a discharge circuit assembly, a first radiator 40, and a second radiator 30, as will be explained in detail below.

[0026] The first radiator 40 is a component of the cooling assembly 1 and is adapted to dissipate heat from electronic and hydraulic components of a system. The first radiator 40 is stacked with the second radiator 30. The first radiator 40 is designed to allow air from the first radiator 40 to be sucked through the second radiator 30.

[0027] The second radiator 30 is another component of the cooling assembly 1 and is adapted to dissipate heat from the system. As mentioned above, the second radiator 30 is stacked with the first radiator 40. The second radiator 30 is a type of radiator for dissipating heat and may be used for dissipating heat from electronic or hydraulic systems. The second radiator 30 is designed to allow air from the second radiator 30 to be sucked through the fan 20.

[0028] Figure 1 b provides a perspective view of the cooling assembly 1 , focusing on the fan 20 and the fan motor 10. This view highlights the mechanical connection between these two components, emphasizing their integral role in the1137277 assembly's cooling function. The perspective view allows for a clear understanding of how the fan motor 10 drives the rotation of the fan 20, which is essential for generating the airflow needed to dissipate heat from the radiators. It should be noted that the fan motor 10 is positioned in front of the fan 20.

[0029] The fan 20 is a critical component of the cooling assembly 1 , responsible for generating the airflow needed to draw heat away from the radiators and dissipate it into the surrounding environment. The fan 20 is strategically positioned within the assembly, typically situated between the fan motor 10 and the second radiator 30, to facilitate the efficient flow of air through the system. A key characteristic of the fan 20 is its high pressure and high airflow capability, which ensures effective cooling even in demanding operating conditions where high heat loads are encountered.

[0030] The specific type of fan 20 employed can vary depending on the specific application and performance requirements. Examples of fan 20 types that may be suitable include axial fan, centrifugal fan, and cross-flow fan, each offering unique airflow characteristics and pressure capabilities.

[0031] The fan motor 10 is the driving force behind the operation of the cooling assembly 1 , providing the rotational power needed to spin the fan 20. This motor is mechanically connected to the fan 20, ensuring that the rotational force generated by the motor is directly transferred to the blades of the fan 20. The design of the fan motor 10 prioritizes compactness, minimizing its physical footprint within the overall assembly. This is particularly important in applications where space constraints are a concern, such as in mining and construction machines.

[0032] In certain embodiments of the invention, the fan motor 10 is designed as a high voltage motor. This means that the motor is designed to operate effectively at voltages above 60 volts. The use of a high voltage motor offers several advantages, including increased power output and improved efficiency, which are beneficial for maintaining optimal cooling performance in demanding environments.1137278

[0033] Figure 2a provides a front view of the cooling assembly 1 , offering a clear perspective on the arrangement and connection of the fan 20 and the fan motor 10. This view is particularly useful for understanding how these two components are integrated and how their design contributes to the overall efficiency and compactness of the cooling assembly 1 . The front view shown in Figure 2a allows for a direct visual assessment of the diameter and blade configuration of the fan 20, which are essential factors in determining its airflow characteristics.Additionally, this view highlights the mounting and alignment of the fan motor 10 relative to the fan 20, emphasizing the importance of their precise positioning for optimal performance and minimal vibration.

[0034] Figure 2b provides a side view of the cooling assembly 1 , offering a comprehensive perspective on the arrangement of key components, including the fan 20, the fan motor 10, the first radiator 40, and the second radiator 30. The side view shown in Figure 2b allows for a clear understanding of the spatial relationships between these components, emphasizing the stacked configuration of the radiators and their positioning relative to the fan 20. This view is crucial for visualizing how the assembly's design contributes to efficient heat dissipation.

[0035] Figure 2c provides a top view of the cooling assembly 1 , offering a perspective on the arrangement of the fan 20 and the fan motor 10. This view is particularly useful for understanding the footprint and spatial requirements of these components within the overall assembly. The top view shown in Figure 2c allows for a clear assessment of the diameter and the position relative to the mounting points of the fan motor 10. This perspective is essential for evaluating how the assembly would be integrated into a system with potential space constraints, such as the engine compartment of a mining or construction machine.

[0036] Figure 3 provides a sectional view of the cooling assembly 1 , offering a detailed internal perspective on the arrangement of key components and the path of airflow through the system. This view is particularly insightful as it reveals the interaction between the fan 20, the fan motor 10, the first radiator 40, and the second radiator 30 during operation. The sectional view shown in Figure 3 allows1137279 for a clear understanding of how the air is drawn in and directed through the assembly, highlighting the role of each component in facilitating efficient heat exchange and dissipation. More specifically, air is sucked through the first radiator 40, the second radiator 30, passing through the fan 20 and around the fan motor 10, to leave the cooling assembly 1.

[0037] Figure 4 presents a block diagram that illustrates the electrical connections and functional relationships between the fan motor 10, the motor drive unit 50, and the discharge circuit assembly 60. This diagram provides a representation of how these components work together, wherein the motor drive unit 50 is electrically connected to the fan motor 10 for providing electrical power thereto. The motor drive unit 50 is also electrically connected to the discharge circuit assembly 60, by means of which residual electrical energy can be discharged. In this context, the discharge circuit assembly 60 is defined as including components to be discharged.

[0038] The discharge circuit assembly 60 is provided in the cooling assembly 1 , acting as a crucial safety mechanism to protect the motor drive unit 50 and other sensitive electrical components from the potentially damaging effects of residual high voltages. When the cooling assembly 1 is deactivated, it may retain a residual amount of stored electrical energy, like a reservoir. This stored energy, if not properly managed, can lead to voltage spikes that could potentially damage sensitive electronics within the system. The discharge circuit assembly 60 steps in to provide a designated pathway for this residual energy to dissipate safely. It acts as a controlled conduit, effectively preventing voltage spikes that could disrupt or harm the delicate electronics within the cooling assembly 1. In certain implement- tations, the discharge circuit assembly 60 might be strategically designed to incorporate a combination of components, including capacitors, resistors, and specialized switching devices. These components work together, each playing a specific role in ensuring the safe and controlled discharge of residual high voltages. Capacitors act as temporary energy storage units, absorbing excess voltage and releasing it slowly. The specific configuration of the discharge circuit assembly 60 is designed based on the unique characteristics of the motor drive11372710 unit 50 and the system's operating voltage, ensuring optimal protection for the entire cooling assembly 1.

[0039] Figure 5 provides a schematic diagram of the discharge circuit assembly 60, illustrating its internal components and their connections. This diagram focuses on a specific embodiment where the discharge circuit assembly 60 is designed to discharge a single Y-pole through an active discharge circuit on the opposite pole. The schematic diagram in Figure 5 uses standard electrical symbols to represent the capacitors. These symbols, along with the interconnecting lines, clearly depict the electrical pathways and the flow of current during the discharge process.

[0040] A positive de bus 61 is the positive voltage rail within the discharge circuit assembly 60, serving as the primary path for positive DC current flow. The positive de bus 61 connects to the positive terminal of the motor drive unit 50 and other components requiring a positive DC voltage. During discharge, the positive de bus 61 provides a path for the stored electrical energy in the motor drive unit 50 to flow through a single discharge circuit 67 to earth 63.

[0041] The negative de bus 62 is the negative voltage rail within the discharge circuit assembly 60, acting as the primary path for negative DC current. It connects to the negative terminal of the motor drive unit 50 and other components needing a negative DC voltage. During discharge, the negative de bus 62 provides a return path for the current flowing through the single discharge circuit 67, completing the electrical circuit and allowing the safe discharge of residual high voltages.

[0042] Within the discharge circuit assembly 60, as depicted in Figure 5, a first capacitor 64, “the X capacitor”, plays a role in ensuring the safe and efficient discharge of residual high voltages from the motor drive unit 50. As a passive electronic component provided between the positive de bus 61 and the negative de bus 62, the first capacitor 64 stores and releases electrical energy, acting as a temporary energy buffer during the discharge process. The first capacitor's 64 capacitance value, a measure of its energy storage capacity, and its voltage rating, the maximum voltage it can safely handle, are selected to ensure reliable operation within the discharge circuit assembly 60. These parameters are deter-mined based on factors such as the operating voltage of the motor drive unit 50, the amount of energy that needs to be discharged, and the desired discharge time.

[0043] Figure 5 illustrates the inclusion of a capacitor 65 within the discharge circuit assembly 60 between the positive de bus 61 and earth 63, “the first Y capacitor”, and a capacitor 66 provided between the negative de bus 62 and earth 63, “the second Y capacitor”. In other words, the first Y capacitor 65 and the second Y capacitor 66 are provided in series between the positive de bus 61 and the negative de bus 62, with a connection to earth 63 between the capacitors.

[0044] Figure 5 shows a single discharge circuit 67 as a critical part of the discharge circuit assembly 60, providing a dedicated pathway for discharging high voltages from the motor drive unit 50 when the cooling assembly 1 is deactivated. The strategic placement of the single discharge circuit 67 within the discharge circuit assembly 60 ensures a controlled and safe discharge process. The single discharge circuit 67, which in this embodiment is provided in parallel with the first Y capacitor 65 between the positive de bus 61 and earth 63, preferably comprises a resistor and a switching device connected in series. When the single discharge circuit 67 is closed during a discharge operation, a current path is closed for discharging the capacitors. This path goes from the negative de bus 62, via the motor drive unit 50, the positive de bus 61 , the single discharge circuit 67 to earth 63. More specifically, the X and Y capacitors 64, 65, and 66 of the motor drive unit 50 are discharged by discharging the X capacitor 64 through an active X discharge of the motor drive unit 50, discharging the first Y capacitor 65 through the discharge circuit 67 on the same pole, and discharging the second Y capacitor 66 through the discharge circuit 67 on the opposite pole, through the active X discharge of the motor drive unit 50.

[0045] Using an inverter / motor combination with active X discharge removes the requirement of having an independent X discharge circuit. In addition to this, due to the increased speed of discharge seen with such switching converters, it is possible to discharge a single Y-pole through an active discharge circuit on the opposite pole (e.g. discharging any capacitors on the Y-negative pole through the12Active Y-positive discharge circuit and the Active X discharge circuit of the Inverter / Motor). This assembly therefore reduces the required number of independent active discharge circuits from 3 to 1 .

[0046] Figure 6 provides a schematic diagram of the motor drive unit 50, specifically illustrating its implementation as an inverter. Inverters are electronic circuits that convert DC power to AC power. In the context of the cooling assembly 1 , the inverter-based motor drive unit 50 is responsible for converting the DC power from a suitable source into three-phase AC power to drive the fan motor 10. The schematic diagram in Figure 6 details the internal structure of the inverter, showing the arrangement of key components such as transistors, capacitors, and inductors. It highlights the three distinct legs or phases of the inverter, each responsible for generating one phase of the three-phase AC output.

[0047] The motor drive unit 50 serves as the brain of the fan motor 10, orchestrating both the conversion of electrical power and the precise control of operational parameters. It receives electrical power, in this embodiment sourced from a DC supply, and transforms it into three-phase alternating current to energize the fan motor 10. The motor drive unit 50 governs the speed and torque of the fan motor 10. This fine-tuned control over the fan motor 10 directly translates to precise management of the airflow generated by the fan 20, ensuring optimal cooling performance. In the shown embodiment, the motor drive unit 50 is designed as a three-phase inverter, having a first leg 54a, a second leg 54b, and a third leg 54c powering a three-phase AC fan motor 10. However, it is also possible to provide the motor drive unit 50 as a single-phase inverter, powering a singlephase AC motor. Alternatively, the motor drive unit 50 may be designed as a DC- DC converter, powering a DC motor.

[0048] During operation, the motor drive unit 50 converts DC power into three- phase AC power, a format commonly employed for driving high-power motors, such as those found in demanding industrial settings. The utilization of a three- phase inverter brings a trio of benefits to the forefront: increased efficiency, ensuring that power is utilized optimally; smoother motor operation, reducing wearand tear and extending the lifespan of the motor; and the remarkable capacity to regulate both motor speed and direction, providing unparalleled control over the cooling process.

[0049] The positive supply bus 51 acts as the backbone for positive DC current distribution within the inverter-based motor drive unit 50, ensuring a consistent and reliable flow of power to the inverter's switching legs. It serves as the primary pathway for positive DC current to flow from the DC power source to the inverter's switching legs, which are responsible for generating the AC output. The positive supply bus 51 is directly connected to the positive terminal of the DC power supply, receiving the DC power that will be converted into AC power. This bus acts as a distribution hub, delivering the positive voltage to the First, Second, and third leg 54c, 54b, 54c of the inverter, each of which requires a positive voltage supply for proper operation. The voltage level on the positive supply bus 51 is typically equivalent to the DC input voltage of the motor drive unit 50, ensuring that the inverter legs receive the full voltage required for efficient power conversion.

[0050] The negative supply bus 52 serves as the return path for negative DC current within the inverter-based motor drive unit 50, completing the electrical circuit and ensuring a safe and efficient flow of current. It acts as the counterpart to the positive supply bus 51 , providing a path for the current to return to the DC power source after passing through the inverter's switching legs. The negative supply bus 52 is directly connected to the negative terminal of the DC power supply, providing a low-voltage reference point for the inverter's operation. The voltage on the negative supply bus 52 is typically at or near ground potential, ensuring that there is a sufficient voltage difference between the Positive and Negative supply buses for the inverter to operate effectively. This voltage difference is crucial for the proper functioning of the electronic switches within the inverter legs, allowing them to control the flow of current and generate the AC output.

[0051] The first leg 54a is an integral part of the inverter-based motor drive unit50, representing one of the three phases that work together to generate the three-14 phase AC output required to power the fan motor 10. The first leg 54a is designed with two electronic switches, typically transistors, connected in series. These switches are positioned between the positive supply bus 51 and the negative supply bus 52, controlling the flow of electrical current from the positive supply bus 51 to the negative supply bus 52 via a first winding 12a of the fan motor 10. A dedicated control circuit, not explicitly shown in the diagram, generates signals that govern the opening and closing of these switches. This control over the switches allows the inverter to precisely shape the AC waveform on the output, ensuring it meets the specific requirements of the fan motor 10.

[0052] The second leg 54b mirrors the structure and function of the first leg 54a to ensure balanced and efficient power conversion. Like its counterpart, the second leg 54b comprises two electronic switches, typically transistors, connected in series. These switches are positioned between the positive supply bus 51 and the negative supply bus 52, effectively regulating the flow of electrical current. The point between the two switches is connected to a second winding 12b of the fan motor 10. A distinction between the second leg 54b and the first leg 54a lies in the timing of their control signals. The control signals for the switches in the second leg 54b are precisely phase-shifted by 120 degrees relative to the first leg 54a. This phase shift is not arbitrary; it is a fundamental requirement for generating a rotating magnetic field within the fan motor 10. This rotating magnetic field is the driving force behind the motor's rotation, and the precise phase relationship between the inverter legs is crucial for its proper operation.

[0053] The third leg 54c completes the three-phase configuration of the inverterbased motor drive unit 50, mirroring the structure and function of the first leg 54a and the second leg 54b, to ensure a balanced and robust power conversion system. Like its counterparts, the third leg 54c features two electronic switches, typically transistors, connected in series. These switches are positioned between the positive supply bus 51 and the negative supply bus 52, effectively controlling the flow of electrical current. The point between the two switches is connected to a third winding 12c of the fan motor 10.11372715

[0054] The control signals for the switches in the third leg 54c are precisely phase-shifted by 240 degrees relative to the first leg 54a, ensuring that the three phases of the AC output are evenly spaced in time. This balanced three-phase output is crucial for the smooth and efficient operation of the fan motor 10, as it creates a balanced rotating magnetic field that drives the motor's rotation.

[0055] Finally, a stabilizing inverter capacitor 53 is provided between the positive supply bus 51 and the negative supply bus 52.

[0056] Figure 7 provides a clear and detailed illustration of the airflow path within the cooling assembly 1 , emphasizing the role of each component in facilitating efficient heat dissipation. This figure serves as a visual guide to understanding how the arrangement and interaction of the fan motor 10, the first radiator 40, and the second radiator 30 contribute to the assembly's overall cooling performance. The figure utilizes arrows to depict the precise direction of airflow, allowing for a comprehensive understanding of the air's journey as it enters, travels through, and exits the cooling assembly 1. This visual representation is particularly useful for comprehending the sequential nature of the airflow and how it interacts with each component to achieve optimal heat exchange.

[0057] The airflow path, as depicted in Figure 7, begins at the intake side of the fan 20. The fan 20, driven by the rotational force provided by the fan motor 10, acts as the driving force behind the airflow, creating a pressure difference that draws ambient air into the cooling assembly 1 . The strategic positioning of the fan 20 at the intake ensures that a constant supply of cool air is drawn into the system.

[0058] The fan 20 draws ambient into the first radiator 40. This ambient air normally has a temperature of 15 - 30 degrees C, preferably about 20 degrees C and in one embodiment has a negative pressure of -0.4 - 0.8 Bar, preferably about -0.6 Bar. After having passed the first radiator 40, the air flow continues into and through the second radiator 30 at a temperature of about 20 - 40 degrees C, preferably about 30 degrees C and a negative pressure of -0.3 - -0-5 Bar, preferably about -0.4 Bar. As the air passes through the second radiator 30, it absorbs heat from the radiator's fins and tubes, which carry the heated fluid from11372716 the system being cooled. This heat transfer process effectively lowers the temperature of the fluid while simultaneously raising the temperature of the air.

[0059] The now-warmed air continues its journey through the fan 20 and passes the fan motor 10, having been further heated to 30 - 50 degrees C, preferably approximately 40 degrees C and between - 0.1 and -0.3 Bar, preferably about -0.2 Bar. After having passed the fan motor 10, the air flow has a temperature of 30 - 50 degrees C, preferably about 40 degrees C and a pressure of 1 .0 Bar.

[0060] The stacked configuration of the radiators, with the second radiator 30 positioned after the first radiator 40 in the airflow path, is a key design element that contributes to the overall efficiency of the cooling assembly 1 . This arrangement, while seemingly counterintuitive, offers several advantages.

[0061] Firstly, it allows for a more compact design. By stacking the radiators vertically, the cooling assembly 1 occupies a smaller footprint, which is particularly beneficial in applications where space constraints are a concern, such as in mining and construction machines.

[0062] Secondly, the stacked configuration promotes more efficient heat transfer. As the air passes through the first radiator 40, it preheats the air before it reaches the second radiator 30. This preheating effect increases the temperature difference between the air and the fluid within the second radiator 30, enhancing the rate of heat transfer.

[0063] Lastly, the stacked configuration allows for a more even distribution of airflow across both radiators. This ensures that both radiators contribute equally to the cooling process, maximizing the assembly's overall cooling capacity.

[0064] In conclusion, Figure 7 effectively illustrates the well-engineered airflow path within the cooling assembly 1 , highlighting the importance of component arrangement and interaction in achieving efficient heat dissipation. The figure underscores the advantages of the stacked radiator configuration, emphasizing its contribution to the assembly's compact design, enhanced heat transfer efficiency, and balanced airflow distribution.11372717

[0065] Embodiments of a cooling assembly for a mining and / or construction machine and a method for cooling electric and hydraulic systems of an electric mining machine with a cooling assembly have been described. It will be realized that these can be varied within the scope of the appended claims without departing from the inventive idea. For example, different pressures and temperatures have been mentioned as examples, but a cooling assembly according to the invention can operate at other temperatures or in other pressure ranges.

Claims

11372718Claims1 . A cooling assembly (1 ) for a mining and / or construction machine, the assembly comprising: a fan (20); a fan motor (10) mechanically connected to the fan (20) and configured to rotate the fan (20); a motor drive unit (50) electrically connected to the fan motor (10) and configured to provide electrical power to drive the fan motor (10); a discharge circuit assembly (60) electrically connected to the motor drive unit (50) and adapted to discharge residual high voltages in the cooling assembly (1 ), wherein the discharge circuit assembly (60) comprises a discharge circuit (67), an X capacitor (64) provided between a positive de bus (61 ) and a negative de bus (62), a first Y capacitor (65) provided between the positive de bus (61 ) and earth (63), and a second Y capacitor (66) provided between the negative de bus (62) and earth, and wherein the discharge circuit is provided between the positive de bus (61 ) and earth; adaption; a first radiator (40); and a second radiator (30) stacked with the first radiator (40), wherein the first radiator (40) is designed to allow air to be sucked through the second radiator (30) and the second radiator (30) is designed to allow air to be sucked through the fan (20).

2. The cooling assembly (1 ) according to claim 1 , wherein the discharge circuit assembly (60) is adapted to discharge the second Y capacitor (66) through a discharge circuit (67) on the opposite pole of a positive de bus (61 ) and the negative de bus (62).

3. The cooling assembly (1 ) according to claim 1 , wherein the discharge circuit (67), preferably a resistor and a switch provided in series, is provided between the positive de bus (61 ) and earth (63), creating a discharge current path during discharge.113727194. The cooling assembly (1 ) according to any of claims 1 to 3, wherein the discharge assembly (60), in conjunction with the motor drive unit (50) is adapted to discharge two Y-poles and one X-pole.

6. The cooling assembly (1 ) according to any one of claims 1 to 5, wherein the discharge circuit assembly (60) is provided in conjunction with a switch-mode converter with active X discharge capabilities.

7. The cooling assembly (1 ) according to any one of claims 1 to 6 , wherein the fan (20) has high pressure and high airflow capability.

8. The cooling assembly (1 ) according to any one of claims 1 to 7, wherein the fan motor (10) is a high voltage motor, preferably a motor adapted to be supplied by a voltage above 60 volts.

9. The cooling assembly (1 ) according to any one of claims 1 to 8, wherein the motor drive unit (50) is in the form of a three-phase inverter.

10. The cooling assembly (1 ) according to any one of claims 1 to 9, wherein the first radiator (40) and the second radiator (30) dissipate heat from electronic and / or hydraulic components of a system of the electric mining and / or construction machine.11 . The cooling assembly (1 ) according to any of claims 1 to 10, wherein a cooling medium for cooling said mining and / or construction machine comprises at least on of liquid to liquid or air to liquid heat exchanging devices.

12. The cooling assembly (1 ) according to any of claims 1 to 11 , wherein the cooling assembly (1 ) is suitable for cooling at least one of electric, hydraulic systems and compressor oil of said mining and / or construction machine.1137272013. A method for cooling systems of an electric mining machine with a cooling assembly (1), the method comprising the following steps: bringing a fan (20) to rotate by means of a fan motor (10) powered by a motor drive unit (50), bringing air to flow through a first radiator (40) by means of the fan (20), bringing the air flowing through the first radiator (40) to flow through a second radiator (30) by means of the fan (20), bringing the air flowing through the second radiator (30) to flow through the fan (20), and discharging the cooling assembly by means of a discharge circuit (67) of a discharge circuit assembly (60), comprising discharging X and Y capacitors of discharge circuit assembly (60) by: discharging an X capacitor (64) through an active X discharge of discharge circuit assembly (60), discharging a first Y capacitor (65) through said discharge circuit (67) on the same pole, and discharging a second Y capacitor (66) through said discharge circuit (67) on the opposite pole, through the active X discharge of the discharge circuit assembly (60);

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