EP3251750A1 - Stationary garbage shredding device comprising an energy accumulator - Google Patents

Abstract

The stationary waste chopping device according to the invention comprises at least one comminution shaft, at least one electric motor for driving the at least one comminution shaft, a power supply connection for supplying the stationary waste comminution device with electrical energy and an energy store for storing energy and at least partially supplying the at least one electric motor with electrical energy, in particular to cover power peaks. Furthermore, the invention provides a corresponding method for operating the stationary waste crusher.

Description

Field of the invention

The invention relates to a stationary waste crusher with at least one shredding shaft, at least one electric motor for driving the at least one shredding shaft and a power supply connection for supplying the stationary waste shredding device with electrical energy.

In all of the following descriptions, both in relation to the prior art and the description of the invention, only one component of the system is cited for the sake of simplicity. Of course, two or more components may be present or provided in the system. For example, always listed a crushing shaft or a generator or electric motor. Depending on the size reduction system, it can also be two or more comminution waves. Also with regard to the drive components, e.g. also be multiple internal combustion engines, generators, electric motors or energy storage and other multiple components.

State of the art

Waste crushing devices designed for stationary operation may include, for example, a diesel engine or an electric motor for driving a crushing shaft.

In the case of an electrical drive of the crushing shaft is provided a connection for a power grid. The stationary waste crusher is then operated exclusively with electrical energy from the mains. However, because fluctuations in the demand for electrical energy occur during operation of the waste crusher, for example because solid and soft comminuted material is mixed or because the force to be applied for comminuting the random orientation of the Good depends on the crushing shaft, peak loads can occur, which are sometimes significantly above the average load. Such load peaks are to be provided by the electric motor or the electrical power supplied to the electric motor from the power grid.

Likewise, the startup current at startup, which can be up to four times the nominal current of the electric motor, has a negative effect on the total energy costs of such a comminuting system.

In the prior art, it is attempted to counteract these negative aspects by so-called switching devices for soft starting or by frequency converters. This succeeds only very inadequate. These switching devices are also not very popular with the network operators, since they can lead to a "contamination" of the network by the generation of so-called harmonics.

This procedure according to the prior art is disadvantageous in that more cost-intensive tariffs have to be concluded with regard to the power grid operators, which provide not only the average but also the maximum power take-off. These tariffs are independent of how often the maximum power is taken. Thus, it must be relatively high costs for tariffs with high power spent, even if the maximum power is rarely retrieved.

It is also clear that this is not just about the cost of the so-called work or performance price. In many cases, the power grids in the capacity for the drive power of such stationary shredders are not available at certain locations. In addition, the provided power is measured according to the largest power requirement. In the case of such a shredder so after the starting current and the peak load of the crushing process. For this very high power requirement, the one-time costs for the grid connection and thus for the nationwide grid expansion, and the ongoing costs for the provided power are measured. In addition to the costs of the so-called labor price, there are also the costs of the so-called performance price, which is mostly measured after the highest 15 minutes of the electricity purchase of a month.

In addition to these costs, the additional costs of the so-called hardware are not insignificant. Both the transformer device, or the provision of a diesel generator, when the power supply is not out of the network, the switching and safety systems, as well as the cable connections, must be designed for the maximum occurring peak current, which causes considerable costs.

Description of the invention

The invention is therefore based on the object at least partially overcome the disadvantages mentioned, so to reduce the actually required power connection of the power grid considerably, and the power peaks occurring by the starting current of the electric motor and the load peaks through the crushing process itself, or so far as to avoid possible mitigate.

This object is achieved by a stationary waste crusher according to claim 1. Advantageous further development are defined in the dependent claims.

The stationary waste chopping device according to the invention comprises at least one comminution shaft, at least one electric motor for driving the at least one comminution shaft, a power supply connection for supplying the stationary waste comminution device with electrical energy and an energy store for storing energy and at least partially supplying the at least one electric motor with electrical energy, in particular to cover power peaks. This has the advantage that the portion of the load peaks exceeding the rated power does not have to be covered by the power from the power grid, but is provided by the energy store. Such power peaks can also occur when starting the waste crusher in the form of a starting current. By the invention, a smaller provided power of the power grid is made possible, as if, for example, a portion of the power peaks exceeding the rated power would have to be obtained through the power grid. Accordingly, a weak power grid is less burdened, so that network failures can be avoided.

A refinement of the stationary waste shredding device according to the invention consists in that at least one gear or one gear belt drive can be provided between the at least one electric motor and the at least one shredding shaft. With the transmission or transmission belt drive, a connection between the electric motor and the comminution shaft and / or a load distribution via a drive can be made optionally on a plurality of comminution shafts, such as, for example, via a synchromesh transmission.

Another development of the stationary garbage chopper according to the invention is that it may further include: an AC / DC converter for converting AC power from the power grid terminal into DC power, a DC / AC converter for converting DC power into AC power for the at least one electric motor, and a arranged between the AC / DC converter and the DC / AC converter intermediate circuit with a power management module for coupling the energy storage, each electric motor is an AC motor. In this way, an AC motor can be supplied with energy from the power grid as well as from the energy storage.

Another development of the stationary waste crusher according to the invention is that it may further comprise: an AC / DC converter for converting AC power from the power supply to DC power and an intermediate circuit arranged between the AC / DC converter and the at least one electric motor with an energy management module Coupling of the energy store, each electric motor is a DC motor. In this way, a DC motor can be supplied both with energy from the power grid and from the energy storage.

Another development of the stationary waste shredding device according to the invention is that it can further comprise: a charger provided between the power supply connection and the energy store for charging the energy store, wherein the energy store for the complete supply of the at least one electric motor is provided with electrical energy, wherein, if each electric motor is an AC motor, further comprising a DC / AC converter for converting DC to AC for the at least one electric motor is provided. In this development, the electric motor is operated only with energy from the energy storage, wherein the energy storage is charged with energy from the mains or recharged, in particular continuously when the waste crusher is operated.

The stationary waste chopping device according to the invention or a further development thereof can furthermore comprise a control device for controlling the energy flow between the power supply connection, the at least one electric motor and the energy store. Such a control device controls the storage of the energy and the supply of the individual components of the waste crusher.

The control device can be further developed such that it is designed to limit the maximum power taken from the power supply connection to the rated power, and / or to release a starting process of the waste shredding device only when a minimum amount of energy is contained in the energy storage, and / or after the starting process the waste crusher device to enable the driving of the at least one crushing shaft only when the minimum amount of energy is contained in the energy storage, and / or to control the energy supply from the energy storage to at least one electric motor to cover the exceeding over the rated power of the power supply terminal power peaks, and / or the occurrence of Lastdälern in which a power consumption of the at least one electric motor drops below the rated power of the power grid connection, a difference between the rated power and the power consumption of the at least one electric motor for Charging the energy storage to use, and / or to operate the at least one electric motor as a generator during braking of the at least one crushing shaft and to use the power generated to charge the energy storage and fully charged energy storage, the power generated during the braking process through the power supply in the power grid feed.

The energy storage of the stationary waste crusher may comprise at least one electrical energy storage and / or a mechanical energy storage, wherein the electrical energy storage in particular a rechargeable battery and / or a capacitor (eg supercapacitor, SuperCAP) and / or a superconducting magnetic energy storage, and / or a static Uninterruptible power supply (static UPS) may include and / or wherein the mechanical energy storage in particular may include a dynamic uninterruptible power supply (dynamic UPS) and / or a flywheel energy storage and / or a flywheel storage.

In the case of a mechanical energy storage device, the waste shredding device may include a transducer device for converting electrical to mechanical and mechanical to electrical energy.

The stationary waste chopping device according to the invention or one of its developments can in particular comprise two or more comminution shafts, each with an electric motor or with a common electric motor. Accordingly, the stationary waste crusher may be, for example, a 2-, 3-, or 4-shaft shredder.

The above object is also achieved by a method according to claim 11. Advantageous further developments are defined in the dependent claims. With regard to the advantages of the method according to the invention and its developments, reference is made to the corresponding statements with respect to the waste shredding device according to the invention and its developments.

The method according to the invention for operating a stationary waste crusher (wherein the stationary waste crusher comprises at least one crusher shaft, at least one electric motor, power supply and energy storage) comprises the steps of: supplying the stationary waste grinder with electrical energy via the power supply port; Storing energy in that Energy storage; Driving the at least one comminution shaft with the at least one electric motor; and at least partially supplying the electric motor with electrical energy from the energy store, in particular supplying the electric motor with electrical energy from the energy store to cover a portion of power peaks that exceeds a nominal power of the power grid connection.

The method according to the invention can be further developed such that the further step of controlling the energy flow between the power supply connection, the at least one electric motor and the energy store is provided.

This may be further developed in that the method further comprises limiting the maximum power drawn from the power supply to the rated power, and / or starting the waste grinder when a minimum amount of energy is contained in the energy storage, and / or driving the at least one comminution shaft after the starting operation of the waste grinder if the minimum amount of energy is contained in the energy storage, and / or controlling the energy supply from the energy storage to at least one electric motor to cover the above the rated power of the power supply connection beyond power peaks, and / or charging the energy storage in the occurrence of Lasttälern in which a power consumption of at least one electric motor the rated power of the power grid connection decreases, by utilizing a difference between the rated power and the power consumption of the at least one electric motor, and / or operating the at least e inen electric motor as a generator during a braking operation of the at least one crushing shaft and using the power generated to charge the energy storage, and / or feeding the power generated during a braking operation of the at least one crushing power through the power supply connection in the power grid, especially when fully charged energy storage.

According to another embodiment, the following further steps may be provided: converting AC power from the power supply to DC, using at least a portion of the DC power to store Energy in the energy storage, and converting direct current into alternating current for supplying the at least one designed in the form of an alternating current electric motor with energy from the power grid connection and / or energy from the energy storage.

Another development consists of the steps of converting alternating current from the power supply connection into direct current, using at least part of the direct current to store energy in the energy store, and supplying the at least one electric motor in the form of a direct current motor with energy from the power supply connection and / or energy can be provided from the energy store.

According to another embodiment, the following further steps can be provided: charging the energy store with energy from the power supply connection and completely supplying the at least one electric motor with electrical energy from the energy store.

Further features and exemplary embodiments and advantages of the present invention will be explained in more detail with reference to the drawing. It is understood that this embodiment can not exhaust the entire scope of the present invention. It is further understood that some or all of the features described below may be combined with each other in other ways.

Brief description of the drawings

Fig. 1

shows a first embodiment of the stationary waste crusher according to the invention.

Fig. 2

shows a second embodiment of the stationary waste crusher according to the invention.

Fig. 3

shows a graph with load peaks and load valleys.

Fig. 4

shows a third embodiment of the stationary waste crusher according to the invention.

embodiments

The embodiments described below are only examples of the solution of the problem. Other embodiments for pursuing the objectives according to the invention are conceivable.

In Fig. 1 A first embodiment 100 of the stationary waste chopping device according to the invention is shown.

The stationary waste chopping device according to the invention comprises at least at least one comminuting shaft 80, at least one electric motor 70 for driving at least one comminuting shaft 80, and a power supply connection 10 and energy store 50 for supplying the stationary waste comminuting device with electrical energy.

The stationary waste chopping device according to the invention is essentially characterized by an energy store 50 for storing energy and supplying the at least one electric motor 70 with electrical energy for partially covering the power peaks beyond the rated load of the mains connection 10, caused by the load peaks of the comminuting process.

As shown in the graph Fig. 3 it can be seen, the crushing process takes place with strongly changing torques, and thus strongly changing power consumption of the electric motor 70. The graph clearly shows so-called load peaks and load valleys. In the embodiment of the invention, the rated power of the system and thus the power grid connection 10, preferably in the middle between the expected load peaks and load valleys are designed.

Since the power grid connection 10 in this design can not cover the load peaks that lie above the rated power of the power connection, additional energy must be supplied to the comminution system. This to cover this additional energy required, is through the energy storage 50 to Provided. The power from the power grid is preferably carried out in the size of the rated power of the interpretation.

The additional power required to cover the rated current exceeding proportion of load peaks is thus applied by the energy storage 50 and provided by the electric motor 70 of the crushing shaft 80 as additional power to the power from the grid.

Since the nominal power exceeding portion of the load peaks, must not be covered by the power from the power grid 10, but provided by the energy storage 50, a smaller provided power of the power grid is possible, as if the nominal current exceeding proportion of load peaks by the Electricity 10 would have to be purchased.

The electrical energy store 50 is connected to the intermediate circuit 30 in the embodiment 100. The electrical energy store may be a capacitor in the form of a so-called SuperCAP, a battery or accumulator of very different design or system, or an electric flywheel storage or a similar electrical or mechanical energy store. In this case, a corresponding energy management module 40 is provided for the energy storage 50 for loading and unloading immediately before the energy storage or in the overall control.

A combination of several identical, or several different energy storage is possible. For example, a battery energy storage for the starting process and coverage of the nominal current exceeding starting current from the electric motor of the crusher 100 and a capacitor for the cover of the short-term peak loads.

If again load valleys adjust, as they from the diagram according to Fig. 3 can be seen, the recharging of the energy storage 50 via the power grid 10 is up to the amount of the designed power consumption, so that the energy stored for the further coverage of load peaks is available.

Should it become apparent during operation of such a comminution system that the so-called load valleys for recharging the energy accumulator 50 from the power grid are not sufficient, the recharging of the energy accumulator 50 can also take place by means of a separately arranged internal combustion engine with attached generator, which also supplies its power via an AC / DC Transducer outputs in the intermediate circuit 30.

With the inventive design of the invention, it is also very easy to adjust the speed of the crushing shaft 80 via the electric motor 70 to the actual crushing task. Such an adjustment of the rotational speed may also be necessary in connection with the capacity of the energy accumulator 50. If the ratio of the load peaks, ie an increased energy demand from the energy storage 50, to the Lasttälern, ie the recharge of the energy storage 50 from the network, should not be sufficient to charge the energy storage 50 continuously, the speed of the motor 70 and so the crushing shaft 80th be adjusted so that the ratio of the load peaks to the load valleys is adjusted so that a continuous loading of the energy storage 50 is ensured, even if it is associated with a reduction in throughput.

These stationary shredder described here are also operated at certain intervals, or after the occurrence of certain events, even in the so-called reversing for a very short time, so in a different direction of rotation of the motor 70 and the crushing shaft 80. Such an event, the occasion for a change in the direction of rotation There is, for example, that the feed has built up so strong before the crushing shaft that it no longer comes to actual comminution and so the Dursatzleistung is greatly reduced.

To remedy this, it is necessary to reverse the direction of rotation of the crushing shaft 80 for a short preset time. As a result, the feed material is loosened, and can then be shredded again in the subsequent normal operation with sufficient throughput.

To initiate this reversing, it is necessary, however, first to bring the motor 70 with the crushing shaft 80 to a halt. In order to keep the time required for this as low as possible, the engine 70 is switched over from the engine operation to generator operation. In generator mode, the braking energy can be used to the standstill of the crushing shaft 80 to charge the memory 50, and should its capacity be exhausted, there is a recovery of braking energy against reimbursement to the grid.

Another cause for the peak load of the power grid 10 is the starting current at the start of the electric motor 70 of this stationary crusher. This starting current is generally about four times the rated current. If this additional starting current must be obtained from the grid, the current connection must be made larger by this starting current exceeding the rated power.

Therefore, the invention is also based on the object over the rated current beyond starting current of the electric motor from the energy storage 50 and not to cover from the power grid 10. As a result, the grid connection and the upstream supply, switching and belay devices and cable connections need only be implemented in the size of the rated current of the electric motor, which means a significant cost savings both in the establishment of such a power connection and in the operation of the crusher itself.

To control the shredding device 100 according to the invention, a complex control 90 with extensive software is provided in order to achieve the object underlying the invention. This control must take on the task that from the power grid 10 is never taken a higher power than the specified rated power, and that before the actual starting operation of the electric motor 70 sufficient capacity of the energy storage device 50 is available. After the starting process, the controller 90 must not release the actual comminution process until the energy store 50 has sufficient capacity again after the starting process. In the comminution process itself, the controller 90 has the process control of the additional power supply from the energy storage 50 to the grid power 10 to the electric motor 70 to cover peak loads safely up to its maximum allowable power put. Conversely, the controller 90 has to provide for the occurrence of so-called Lastdälern, for the charging of the energy storage device 50 from the difference of the power supply rated current 10 and the actual current consumption of the electric motor 70. In this case, the controller has 90 corresponding influence on the AC / DC converter 20, DC / AC converter 60 and to take the energy storage management 40, as far as one of these components is not already integrated in the controller 90, so that there is no overload or impermissible Discharge of the energy storage 50 comes.

The energy storage device 50 of the stationary waste crusher 100 may consist, for example, of a battery or a rechargeable battery, wherein preferably lithium-ion cells are used. Furthermore, the embodiment 100 comprises an AC / DC converter 20 which converts the mains current, preferably 400 V AC, into a direct current of the intermediate circuit 30 with 200-800 V, preferably 650 V. Connected to this intermediate circuit is an energy management module 40, which controls the regulation the loading and unloading of the energy storage 50 takes over. At the intermediate circuit 30 is also the DC / AC converter 60 or frequency converter, which provides the alternating current in the predetermined frequency of the electric motor 70 for driving the crushing shaft 80.

In Fig. 2 FIG. 2 shows a second embodiment 200 of the stationary waste chopping device according to the invention.

In the first embodiment 100, the energy store 50 is arranged such that it receives energy from an intermediate circuit 30 via the energy management 40 and releases it into it again. The capacity of this energy storage 50 will only be sized so large that only the load peaks, which is above the average between load peaks and load valleys, can be covered. The required capacity will tend to be relatively low.

The second embodiment 200 provides the energy storage device 50, primarily designed as a battery or rechargeable battery, in the main line of the power supply of the motor 70. The battery is fed via the charger 25 continuously from the network 10 and loaded. Via a DC / AC converter 60, the power is returned to the motor 70, which drives the shaft 80.

The engine 70 also receives the power required to cover the load peaks from the energy store or the battery 50. However, only the power is supplied to the energy store, which corresponds to the coverage of the required power of the middle between the load peaks and load valleys.

In the so-called last valleys, where the energy requirement of the motor 70 is below the above-described middle between load peaks and load valleys, the energy storage or the battery 50, again to the previously taken to cover the load peaks energy can be charged.

In addition to using an AC motor 70 ( Fig. 2A ) with upstream DC / AC converter 60, another embodiment with a DC motor 75 (FIG. Fig. 2B ) to drive the shaft 80 is conceivable, in which case the converter 60 is unnecessary.

According to this embodiment FIG. 2 , the same effect is achieved as with the embodiment 100, so that the network 10 is loaded only in the size that corresponds to the required power that corresponds to the average between the load peaks and load valleys.

The additional energy required to cover the load peaks, and the power for applying the starting current of the motor 70 or 75, covers the energy storage or the battery 50 from. Therefore, in the second embodiment, the capacity of the energy storage device 50 needs to be 200 according to FIG Fig. 2 be designed for the full power of the engine 70 or 75 including the load peaks.

This embodiment according to FIG. 2 may not be economically feasible at current battery costs. However, experience and developments in the battery sector show that the cost will probably decrease by a factor of 10 in 5 years.

In Fig. 4 a third embodiment 300 of the stationary waste crusher according to the invention is shown. This embodiment corresponds to that after Fig. 1 However, instead of a crushing shaft in the first embodiment here two crushing shafts 80, 81 are provided (two-shaft shredder). The optional connection between the electric motor 70 and the crushing shafts 80, 81 via a transmission 90 (for example, a synchronous transmission).

The illustrated embodiments are merely exemplary and the full scope of the present invention is defined by the claims.

Claims (15)

A stationary waste crusher, comprising: at least one comminution shaft; at least one electric motor for driving the at least one crushing shaft; and a power supply connection for supplying the stationary waste crusher with electrical energy; marked by an energy store for storing energy and for at least partially supplying the at least one electric motor with electrical energy, in particular for covering power peaks. The stationary waste crusher of claim 1, further comprising: at least one gear or Getrieberiementrieb between the at least one electric motor and the at least one crushing shaft. A stationary waste crusher according to claim 1 or 2, further comprising: an AC / DC converter for converting AC power from the power grid terminal into DC power, a DC / AC converter for converting DC power into AC power for the at least one electric motor, and one disposed between the AC / DC converter and the DC / AC converter DC link with an energy management module for coupling the energy storage, each electric motor is an AC motor. A stationary waste crusher according to claim 1 or 2, further comprising: an AC / DC converter for converting alternating current from the power supply connection into direct current and an intermediate circuit arranged between the AC / DC converter and the at least one electric motor with a power management module for coupling the energy store, wherein each electric motor is a direct current motor. A stationary waste crusher according to claim 1 or 2, further comprising: a charger provided between the power supply and the energy storage device for charging the energy storage, wherein the energy storage is provided to fully supply the at least one electric motor with electrical energy, wherein, if each electric motor is an AC motor, further comprising a DC / AC converter for converting direct current into AC power is provided for the at least one electric motor. A stationary waste crusher according to any one of claims 1 to 5, further comprising: a control device for controlling the flow of energy between the power grid connection, the at least one electric motor and the energy store. Stationary waste crusher according to claim 6, wherein the control device is designed to
limit the maximum power drawn from the power supply to the rated power, and / or
to release a starting process of the waste shredding device only when a minimum amount of energy is contained in the energy storage, and / or release after starting the garbage shredder driving the at least one crushing wave only when the minimum amount of energy is contained in the energy storage, and / or
to control the energy supply from the energy storage to at least one electric motor to cover the beyond the rated power of the power supply connection power peaks, and / or
when load valleys occur in which a power consumption of the at least one electric motor drops below the nominal power of the power supply, to use a difference between the rated power and the power consumption of the at least one electric motor for charging the energy storage, and / or
during a braking operation of the at least one crushing shaft to operate the at least one electric motor as a generator and to use the power generated to charge the energy storage and feed fully generated energy storage, the power generated during the braking process via the power grid connection in the power grid. Stationary waste crusher according to one of claims 1 to 7, wherein the energy storage comprises at least one electrical energy storage and / or a mechanical energy storage, wherein the electrical energy storage in particular a rechargeable battery and / or a Capacitor and / or a superconducting magnetic energy storage, and / or a static uninterruptible power supply, UPS, and / or wherein the mechanical energy storage in particular comprises a dynamic UPS and / or a flywheel energy storage and / or a flywheel storage. Stationary waste crusher according to claim 8, wherein in the case of a mechanical energy storage, a converter means for converting electrical to mechanical and mechanical energy is provided in electrical energy. Stationary waste crusher according to one of claims 1 to 9, wherein two or more shredding shafts are provided with one or with a common electric motor. A method of operating a stationary waste crusher, the stationary waste crusher comprising at least one crusher shaft, at least one electric motor, a power grid, and an energy store, the method comprising the steps of: Supplying the stationary waste crusher with electrical energy via the power supply connection; Storing energy in the energy store; Driving the at least one comminution shaft with the at least one electric motor; and at least partially supplying the electric motor with electrical energy from the energy store, in particular supplying the electric motor with electrical energy from the energy storage to cover power peaks. The method of claim 11, further comprising the step: Controlling the flow of energy between the power grid connection, the at least one electric motor and the energy storage. The method of claim 12, further comprising: Limiting the maximum power drawn from the power supply to the rated power, and / or Starting the waste crusher when a minimum amount of energy is included in the energy storage, and / or Driving the at least one crushing shaft after the starting process of the waste crusher when the minimum amount of energy is contained in the energy storage, and / or Controlling the power supply from the energy storage to at least one electric motor to cover the beyond the rated power of the power grid connection power peaks, and / or Charging of the energy storage in the occurrence of Lasttälern in which a power consumption of the at least one electric motor drops below the rated power of the power grid connection, by taking advantage of a difference between the rated power and the power consumption of the at least one electric motor, and / or Operating the at least one electric motor as a generator in a braking operation of the at least one crushing shaft and using the power generated thereby for charging the energy storage, and / or Feeding the power generated in a braking operation of the at least one crushing shaft via the power grid connection in the power grid, in particular when fully charged energy storage. Method according to one of claims 11 to 13, with the further steps: Converting AC power from the power grid connection to DC power, using at least a portion of the DC power to store energy in the energy storage, and converting DC power into AC power to power the at least one AC motor shaped electric motor from the power grid terminal and / or energy from the energy storage , Method according to one of claims 11 to 13, with the further steps: Converting alternating current from the power supply connection into direct current, using at least a portion of the direct current to store energy in the energy storage device, and supplying the at least one electric motor in the form of a direct current motor with energy from the power supply connection and / or energy from the energy storage device.

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