Patent Description:
In recent years, wind-driven generator systems have been gradually developed towards high power density, and the loss of the wind-driven generator system itself has increased accordingly, and the number of components that need heat dissipation simultaneously has also increased. Heat-generating components, such as a generator, a shafting, a pitch system, a nacelle cabinet, a nacelle, a converter cabinet and a transformer, need to undergo necessary heat dissipation and cooling treatment to achieve the normal operation of each heat-generating component, especially for an offshore wind-driven generator system, in which the heat-generating components are arranged in an E-TOP structure of the nacelle, resulting in more and more complex configuration and layout of the overall cooling system of the generator system in the nacelle. Therefore, it is necessary to design a more compact cooling system structure layout in the limited space of the nacelle, and the integrated cooling system design has become an important research direction.

D1 (<CIT>) provides a cooling system, a wind power generating set, and a controlling method of the cooling system. The cooling system includes a plurality of cooling sub-systems. Each cooling sub-system is used for conducting heat exchanging with heating components of corresponding sorts. The cooling sub-systems include cooling loops. The cooling loops include power pumps, heat exchanging branch circuit sets and heat dissipating sets which are connected by liquid circuits. Branch circuit heat exchangers of each heat exchanging branch circuit in the heat exchanging branch circuit sets are used for being arranged at the corresponding heating components. The cooling loops are used for conducting heat exchanging with the heating components by an inner flowing cooling medium, and therefore the temperature of the heating components can be maintained in the preset range.

D2 (<CIT>) provides a novel spiral plate type heat exchanger. The novel spiral plate type heat exchanger includes a heat exchanger body, wherein the heat exchanger body includes a first spiral plate and a second spiral plate; and the first spiral plate is spirally wound to form a first heat exchange channel, the second spiral plate is adjacent to the first spiral plate and spirally wound to form a second heat exchange channel, and a third heat exchange channel is formed between the first spiral plate and the second spiral plate.

D3 (<CIT>) relates to a water circulation system associated with a refrigerant cycle that includes an intermediate heat exchanger having a triple-pipe shape in which three independent flow passages are formed by three pipes having a concentric axis and different diameters.

An object of the present application is to provide a cooling system and a wind-driven generator system. The cooling system can achieve balanced utilization of cold capacity and heat capacity and reduce system power consumption.

In one aspect, the present application proposes a cooling system. The cooling system comprises a first cooling loop, a second cooling loop, a third cooling loop, a first heat exchanger and a second heat exchanger, wherein the first cooling loop comprises a first fluid pipeline for cooling a first heat-generating component and a first pump set, and the first pump set is configured to cause a first cooling medium to circulate within the first fluid pipeline; the second cooling loop comprises a second fluid pipeline for cooling a second heat-generating component and a second pump set, the second fluid pipeline comprises a main path and a bypass, and the second pump set is configured to cause a second cooling medium to circulate within the main path or within the main path and the bypass; the third cooling loop comprises a third fluid pipeline for cooling a third heat-generating component and a third pump set, the third pump set is configured to cause a third cooling medium to circulate within the third fluid pipeline, and the third fluid pipeline communicates with both the first heat exchanger and the second heat exchanger, the third heat-generating component generating more heat than the first heat-generating component but generating less heat than the second heat-generating component; the first heat exchanger is configured to thermally couple the first cooling medium, the second cooling medium and the third cooling medium to one another in a manner in which the first cooling medium, the second cooling medium and the third cooling medium are isolated from one another; the second heat exchanger is configured to thermally couple the second cooling medium to the third cooling medium through the bypass in a manner in which the second cooling medium and the third cooling medium are isolated from each another.

In another aspect, the present application further provides a wind-driven generator system. The wind-driven generator system comprises: a first heat-generating component including at least one of a shafting, a cable, a nacelle, a pitch system, a nacelle cabinet, and a nacelle base; a second heat-generating component including a generator; a third heat-generating component including at least one of a transformer, a converter, and an auxiliary transformer; and any one of the cooling system as described above.

The cooling system provided by the present application includes the first cooling loop, the second cooling loop and the third cooling loop that operate independently from one another, as well as the first heat exchanger and the second heat exchanger. Through the liquid-liquid three-way first heat exchanger, the first cooling medium in the first cooling loop, the second cooling medium in the second cooling loop and the third cooling medium in the third cooling loop are thermally coupled in a manner in which these cooling media are isolated from one another. First, under suitable ambient temperature conditions, in a case where the temperature control requirement of the first heat-generating component of the small-capacity cooling system is satisfied, the surplus cooling load of the first cooling loop can be distributed to the generator cooling system of the second cooling loop and the electrical cooling system of the third cooling loop through the first heat exchanger, achieving a full utilization of the cooling capacity. Second, for the generator cooling system, the surplus cooling capacity from the small capacity cooling system is absorbed through the first heat exchanger to achieve over-generating of the generator system or achieve frequency conversion and energy saving of the rotating parts at the end of the generator system. Third, through the first heat exchanger, heat balance among the small-capacity cooling system, the generator cooling system and the electrical cooling system is achieved. At the same time, through the liquid-liquid two-way second heat exchanger, the second cooling medium in the bypass of the second cooling loop and the third cooling medium in the third cooling loop are thermally coupled in a manner in which these cooling media are isolated from each other, thereby a part of the residual heat carried by the second cooling loop is used for the heating of the third cooling loop, so as to achieve the appropriate application of the residual heat. While the heat dissipation requirement is satisfied, the balanced utilization of cold capacity and heat capacity is achieved through the thermal coupling between the cooling loops in which the cooling loops are isolated from one another, and the system power consumption is reduced.

The present application can be better understood from the following description of specific implementations of the present application in conjunction with the accompanying drawings, wherein other features, objects and advantages of the present application can be more apparent by reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, and the same or similar reference numbers refer to the same or similar features.

Features of various aspects and exemplary embodiments of the present application are described in detail below. Numerous specific details are disclosed in the following detailed description to provide a thorough understanding of the present application. However, it will be apparent for those skilled in the art that the present application may be implemented without some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present application by illustrating examples of the present application The scope of protection sought is defined by the appended claims.

With the rapid development of wind-driven generator systems, a capacity of a single wind-driven generator system increases. The loss of the wind-driven generator system itself increases. In addition, the number of components that need heat dissipation also increases. Especially, with the development of the E-TOP layout structure of large-capacity offshore generator system, heat-generating components, such as a generator, a shafting, a pitch system, a nacelle cabinet, a converter cabinet and a transformer, are all arranged in the nacelle, and these heat-generating components need independent necessary heat dissipation and cooling treatments, which leads to an increasing number of cooling subsystems in the nacelle, and the configuration of the cooling subsystems becomes more and more complex. In view of the different control strategies, processes and layout positions of each cooling subsystem, a large deviation in the cooling distribution of each heat-generating component during the actual operation is likely to occur, and the system power consumption is large. It is urgently needed to optimize the overall layout and structure of the cooling subsystem of each heat-generating component of the wind-driven generator system, to appropriately utilize and distribute the heat capacity and cooling capacity of the system.

The purpose of the present application is to provide a multi way-coupled cooling system of a wind-driven generator system, which is especially suitable for using in a high-power offshore direct-drive permanent-magnet wind-driven generator system with the E-TOP layout. For a generator system that do not adopt the E-TOP layout (that is, not all main heat-generating components thereof are positioned in the nacelle), if the pipeline complexity is not considered, the multi way-coupled cooling system of the present application can also be used, that is, for the generator system, according to the actual positions of the heat-generating components, the same layout concept can be used in the layout of the respective cooling subsystems, and the overall layout of the cooling subsystems of the heat-generating components is optimized. For a better understanding of the present application, the cooling system and the wind-driven generator system according to the embodiments of the present application will be described in detail below with reference to <FIG>.

With reference to <FIG>, embodiments of the present application provide a wind-driven generator system including: a first heat-generating component <NUM>, a second heat-generating component <NUM>, a third heat-generating component <NUM>, and a cooling system.

The first heat-generating component <NUM> is a combination of components that generate a small amount of heat, and a heat dissipation loss of the first heat-generating component <NUM> is small. Heat-dissipating subsystems of each heat-generating component can be incorporated into one cooling loop or several cooling branches in an integrated manner, so as to satisfy heat dissipation requirements of each heat-generating component. Optionally, the first heat-generating component <NUM> may include at least one of a shafting, a cable, a nacelle, a pitch system, a nacelle cabinet, and a nacelle base.

The second heat-generating component <NUM> is a combination of components that generate a large amount of heat, and the second heat-generating component <NUM> accordingly requires a large heat dissipation loss. Optionally, the second heat-generating component <NUM> may include a generator. Not only the second heat-generating component <NUM> (for example, a generator) generates a large amount of heat, but also the residual heat generated by the second heat-generating component <NUM> can be provided to other heat-generating components in a low temperature environment, so that minimum temperature operation requirements of the heat-generating components in low temperature environment are satisfied.

The third heat-generating component <NUM> is a combination of components that generate a large amount of heat. The third heat-generating component <NUM> generates more heat than the first heat-generating component <NUM>, but generates less heat than the second heat-generating component <NUM>. Optionally, the third heat-generating component <NUM> may include at least one of a transformer, a converter and an auxiliary transformer. In addition, the third heat-generating component <NUM> generally has a required minimum temperature to be maintained, and an increase or decrease of the heat dissipation loss of the third heat-generating component <NUM> is directly proportional to the heat dissipation loss of the second heat-generating component <NUM> (for example, a generator), that is, the third heat-generating component <NUM> and the second heat-generating component <NUM> operate oppositely.

It should be noted that, in actual operation and design, on the basis of the present application, according to the specific number of each type of heat-generating component, different cooling manners and cooling requirements, similar configurations and coupling configurations can be used for each cooling loop to form a whole cooling system. For ease of description, in embodiments of the present application, a first cooling loop <NUM> (i.e., a small-capacity cooling system) for cooling the first heat-generating component <NUM>, a second cooling loop <NUM> (i.e., a generator cooling system) for cooling the second heat-generating component <NUM> and a third cooling loop <NUM> (i.e., the electrical cooling system) for cooling the third heat-generating component <NUM> are used as an example for illustration.

A cooling system provided in the embodiments of the present application includes: a first cooling loop <NUM>, a second cooling loop <NUM>, a third cooling loop <NUM>, a first heat exchanger <NUM> and a second heat exchanger <NUM>.

The first cooling loop <NUM> includes a first fluid pipeline <NUM> for cooling the first heat-generating component <NUM> and a first pump set <NUM> configured to cause a first cooling medium to circulate within the first fluid pipeline <NUM>. The first cooling loop <NUM> communicates with the first heat exchanger <NUM>.

The second cooling loop <NUM> includes a second fluid pipeline <NUM> for cooling the second heat-generating component <NUM> and a second pump set <NUM>. The second fluid pipeline <NUM> includes a main path <NUM> and a bypass <NUM>. The second pump set <NUM> is configured to cause a second cooling medium to circulate within the main path <NUM> or within the main path <NUM> and the bypass <NUM>. The main path <NUM> communicates with the first heat exchanger <NUM>, and the bypass <NUM> communicates with the second heat exchanger <NUM>.

The third cooling loop <NUM> includes a third fluid pipeline <NUM> for cooling the third heat-generating component <NUM> and a third pump set <NUM> configured to cause a third cooling medium to circulate within the third fluid pipeline <NUM>. The third fluid pipeline <NUM> communicates with both the first heat exchanger <NUM> and the second heat exchanger <NUM>. The first heat-generating component <NUM> generates the least heat, the second heat-generating component <NUM> generates the most heat, and the third heat-generating component <NUM> generates the amount of heat between those of the first heat-generating component <NUM> and the second heat-generating component <NUM>.

The first heat exchanger <NUM> is configured to thermally couple the first cooling medium, the second cooling medium and the third cooling medium in a manner in which the first cooling medium, the second cooling medium and the third cooling medium are isolated from one another. The first cooling medium, the second cooling medium and the third cooling medium may be a same liquid medium (for example, water or oil), or may be different liquid media. Optionally, the first heat exchanger <NUM> is a liquid-liquid three-way heat exchanger.

The second heat exchanger <NUM> is configured to thermally couple the second cooling medium and the third cooling medium through the bypass <NUM> in a manner in which the second cooling medium and the third cooling medium are isolated from each other. Optionally, the second heat exchanger <NUM> is a liquid-liquid two-way heat exchanger.

The cooling system provided by embodiments of the present application includes the first cooling loop <NUM>, the second cooling loop <NUM> and the third cooling loop <NUM> that operate independently from one another, as well as the first heat exchanger <NUM> and the second heat exchanger <NUM>. Through the liquid-liquid three-way first heat exchanger <NUM>, the first cooling medium in the first cooling loop <NUM>, the second cooling medium in the second cooling loop <NUM> and the third cooling medium in the third cooling loop <NUM> are thermally coupled in a manner in which these cooling media are isolated from one another. First, under suitable ambient temperature conditions, in a case where the temperature control requirement of the first heat-generating component <NUM> of the small-capacity cooling system is satisfied, the surplus cooling load of the first cooling loop <NUM> can be distributed to the generator cooling system of the second cooling loop <NUM> and the electrical cooling system of the third cooling loop <NUM> through the first heat exchanger <NUM>, achieving a full utilization of the cooling capacity. Second, for the generator cooling system, the surplus cooling capacity from the small capacity cooling system is absorbed through the first heat exchanger <NUM> to achieve over-generating of the generator system or achieve frequency conversion and energy saving of the rotating parts at the end of the generator system. Third, through the first heat exchanger <NUM>, heat balance among the small-capacity cooling system, the generator cooling system and the electrical cooling system is achieved. At the same time, through the liquid-liquid two-way second heat exchanger <NUM>, the second cooling medium in the bypass <NUM> of the second cooling loop <NUM> and the third cooling medium in the third cooling loop <NUM> are thermally coupled in a manner in which these cooling media are isolated from each other, thereby a part of the residual heat carried by the second cooling loop <NUM> is used for the heating of the third cooling loop <NUM>, so as to achieve the appropriate application of the residual heat. While the heat dissipation requirement is satisfied, the balanced utilization of cold capacity and heat capacity is achieved through the thermal coupling between the cooling loops in which the cooling loops are isolated from one another, and the system power consumption is reduced.

With further reference to <FIG>, a bypass regulating valve 212a is arranged on the bypass <NUM>. When the temperature of the third cooling medium is lower than a preset temperature, the bypass regulating valve 212a is opened, so that the second cooling medium within the bypass <NUM> exchanges heat with the third cooling medium through the second heat exchanger <NUM>.

Therefore, under a condition of extremely low temperature, with the second heat exchanger <NUM>, the generator cooling system transfer a part of the heat load generated by the loss to the electrical cooling system through the bypass <NUM>, which not only appropriately utilizes the residual heat of the generator, but also satisfies minimum operation temperature requirements of heat-generating components of the electrical cooling system, such as a transformer, a converter and an auxiliary transformer.

Further, the first heat exchanger <NUM> includes a first heat conduction channel, a second heat conduction channel and a third heat conduction channel spaced apart from one another. The first heat conduction channel includes a first inlet end 41a and a first outlet end 41b. A first water supply pipe <NUM> of the first fluid pipeline <NUM> is connected to the first inlet end 41a. A first water return pipe <NUM> is connected to the first outlet end 41b.

The second heat conduction channel includes a second inlet end 42a and a second outlet end 42b. A second water supply pipe 211a of the second fluid pipeline <NUM> is connected to the second inlet end 42a. A second water return pipe 211b is connected to the second outlet end 42b.

The third heat conduction channel includes a third inlet end 43a and a third outlet end 43b. The third fluid pipeline <NUM> includes a first section <NUM> and a second section <NUM> extending between the first heat exchanger <NUM> and the second heat exchanger <NUM>. The third pump set <NUM> is positioned in the first section <NUM>. The third inlet end 43a is connected upstream of the first section <NUM>, and the third outlet end 43b is connected downstream of the second section <NUM>.

Therefore, a total of six interfaces are arranged on the first heat exchanger <NUM>. The first cooling medium, the second cooling medium and the third cooling medium can transfer heat within the first heat exchanger <NUM> in a co-current or cross-flow manner, so as to realize the mutual transfer and balance of the heat of the three cooling loops. The six interfaces may be disposed on a same side of the first heat exchanger <NUM>, or may be disposed on both sides of the first heat exchanger <NUM> respectively.

The second heat exchanger <NUM> includes a fourth heat conduction channel and a fifth heat conduction channel spaced apart from each other.

The fourth heat conduction channel includes a fourth inlet end 51a and a fourth outlet end 51b. A second bypass water supply pipe 212a of the bypass <NUM> of the second fluid pipeline <NUM> is connected to the fourth inlet end 51a. A second bypass water return pipe 212b of the bypass <NUM> is connected to the fourth outlet end 51b.

The fifth heat conduction channel includes a fifth inlet end 52a and a fifth outlet end 52b. The fifth inlet end 52a is connected downstream of the first section <NUM> of the third fluid pipeline <NUM>, and the fifth outlet end 52b is connected upstream of the second section <NUM>.

Therefore, a total of four interfaces are arranged on the second heat exchanger <NUM>. The second cooling medium and the third cooling medium can transfer heat within the second heat exchanger <NUM> in a co-current or cross-flow manner, thereby realizing the mutual transfer and balance of the heat of the two cooling loops. The four interfaces may be disposed on a same side of the second heat exchanger <NUM>, or may be disposed on both sides of the second heat exchanger <NUM> respectively.

A specific structure of each cooling loop will be described in further detail below with reference to <FIG>.

<FIG> shows a specific structure of the first cooling loop <NUM>. The first cooling loop <NUM> is a small-capacity cooling system, including a first fluid pipeline <NUM>, a first pump set <NUM>, a plurality of first branch heat sinks 11b connected parallel and used for cooling the first heat-generating component <NUM>, and a first heat dissipation unit <NUM> for taking away the heat loss of all components. The first cooling loop <NUM> further includes various functional valves, various sensors, pressure devices and filters, so as to realize normal, stable and maintainable operation of the first cooling loop <NUM>.

The first cooling medium enters from the first heat conduction channel of the first heat exchanger <NUM>, and is transported to the plurality of first branch heat sinks 11b connected in parallel through the first pump set <NUM>. After each branch heat exchanger exchanges heat with each first heat-generating component <NUM>, the first cooling medium converges and flows into the first heat dissipation unit <NUM> and flows into the first heat conduction channel of the first heat exchanger <NUM>.

Specifically, the first pump set <NUM> includes one pump body Pu or at least two pump bodies Pu connected in parallel. When the first pump set <NUM> includes at least two pump bodies Pu connected in parallel, a manner in which the at least two pump bodies Pu operate in parallel may be adopted, or a manner in which some of the pump bodies Pu operate and some of the pump bodies Pu are for backup may be adopted. With comprehensive consideration depending on of factors such as space layout size, system capacity, reliability and cost performance, energy-saving and fault-tolerant operation can be realized, that is, when one pump body Pu fails, the remaining pump body Pu can still meet all or more than <NUM>% of the performance of the system. At the same time, in order to further achieve the optimal energy efficiency of the system, the first pump set <NUM> can adopt a control manner such as fixed frequency operation, high or low speed operation, variable frequency operation, or fault-tolerant operation with at least two pump bodies Pu, which meets the cooling load operation requirement of the first cooling loop <NUM> and improves the fault tolerance performance and effective energy-saving strategies of the system.

Each pump body is provided with a gas discharge valve AV to discharge gas during system operation, thereby protecting the safe operation of the first pump set <NUM>. A check valve SV is arranged at the outlet of each pump body Pu to protect the pump body Pu. A pump body regulating valve PV is arranged at the inlet of each pump body Pu. The pump body regulating valve PV is closed quickly in response to the leakage problem of any one of the pump bodies Pu. A pump body Pu is cut off through a corresponding check valve SV and a corresponding pump body regulating valve PV If the adopted pump body Pu is in a non-mechanical seal form, the setting of the pump body regulating valve PV can be omitted.

Optionally, a pressure stabilizing devices SP is arranged at the inlet of the first pump set <NUM>. The pressure stabilizing devices SP is configured to generate an alarms when a system pressure fluctuation occurs in the system as the temperature changes and prevent the damage to the system. The pressure stabilizing devices SP may be in the form of a high-level water tank or an expansion tank.

Further, a plurality of first fluid branches 11a in one-to-one correspondence with a plurality of first heat-generating components <NUM> are arranged on the first fluid pipeline <NUM>. The plurality of first heat-generating components <NUM> may be, for example, shaftings, nacelles, pitch systems. A first branch heat sink 11b is arranged on each first fluid branch 11a. A first branch regulating valve VV1, a first branch temperature sensor TT1 and a first branch flow sensor FF1 are arranged downstream of each first fluid branch 11a. A first heat dissipation unit <NUM> is further arranged on the first water return pipe <NUM> of the first fluid pipeline <NUM>.

The specific number of the first fluid branches 11a is set according to the number of the first heat-generating components <NUM>. The temperature of the first cooling medium increases after passing through the plurality of first fluid branches 11a, and the first cooling medium enters the first heat dissipation unit <NUM> along the first water supply pipe <NUM>.

A measured value of each first branch temperature sensor TT1 and a measured value of each first branch flow sensor FF1 are monitored. An opening degree of the first branch regulating valve VV1 is controlled according to a target temperature value of each of the first heat-generating components <NUM> to adjust a flow rate of each of the first fluid branches 11a.

By adjusting the opening degree according to the target temperature value of each first heat-generating component <NUM>, the heat exchange requirement of each first heat-generating component <NUM> can be satisfied. The arrangement of the first branch regulating valve VV1 can avoid the problems that the loss values of each first fluid branch 11a are different, the calculation process is prone to lead to deviation, and the flow is prone to unevenness.

Optionally, a first valve V1 is arranged at at least one of the inlet and the outlet of the first pump set <NUM>, the first water supply pipe <NUM> and the first water return pipe <NUM> of the first fluid pipeline <NUM>, the outlet of the first pump set <NUM> and upstream and the downstream of each first fluid branch 11a. By closing the first valve V1, components on a corresponding first fluid branch 11a can be replaced and maintained.

Optionally, a first liquid discharge valve LV1 is further arranged on at least one of the first fluid pipeline <NUM> and each first fluid branch 11a, for local liquid discharge during maintenance and replacement of components.

Optionally, a first filter is arranged at the inlet of the first pump set <NUM> to ensure the cleanliness of the system. In addition, the first filter has a liquid discharge function and can be used as a local liquid discharge point of the first pump set <NUM>.

Optionally, each of the first pump set <NUM> and the first heat dissipation unit <NUM> is provided with a first gas discharge valve AV1. The first heat dissipation unit <NUM> is configured to take away the heat loss of all components and achieve local or high point gas discharge through the first gas discharge valve AV1. The first cooling medium, after passing through the first heat dissipation unit <NUM>, is brought into the first heat exchanger <NUM> under the action of the first pump set <NUM>.

Optionally, a first pressure monitoring device P1 is arranged at at least one of the inlet and the outlet of the first pump set <NUM>, and upstream and downstream of each first fluid branch 11a. Optionally, the first pressure monitoring device P1 includes a first pressure transducer and a first pressure display device. The first pressure transducer is configured for local and remote monitoring of system operation conditions. The first pressure display device is configured for local liquid injection and operation and maintenance observation.

<FIG> shows a specific structure of the second cooling loop <NUM>. The second cooling loop <NUM> is a generator cooling system, including a second fluid pipeline <NUM>, a second pump set <NUM>, a plurality of second branch heat sinks <NUM> connected in parallel and used for cooling the second heat-generating component <NUM>, and a second heat dissipation unit <NUM> for taking away the heat loss of all components. The second cooling loop <NUM> further includes various functional valves, various sensors, pressure stabilizing devices and filters to realize the normal, stable and maintainable operation of the second cooling loop <NUM>.

The second cooling medium enters from the second heat conduction channel of the first heat exchanger <NUM>, and is transported to the plurality of second branch heat sinks <NUM> connected in parallel through the second pump set <NUM>. After each branch heat exchanger exchanges heat with the second heat-generating component <NUM>, when the bypass regulating valve 212a on the bypass <NUM> is opened, the second cooling medium converges and flows into the second heat dissipation unit <NUM> from the main path <NUM> and the bypass <NUM> respectively, and flows into the second heat conduction channel of the first heat exchanger <NUM>.

The second cooling medium entering the bypass <NUM> flows through the fourth heat conduction channel of the second heat exchanger <NUM>, exchanges heat with the third cooling medium, and then joins with the second cooling medium in the main path <NUM>. When the bypass regulating valve 212a on the bypass <NUM> is closed, the second cooling medium directly enters the second heat dissipation unit <NUM> from the main path <NUM> and flows into the second heat conduction channel of the first heat exchanger <NUM>.

Specifically, the second pump set <NUM> includes one pump body Pu or at least two pump bodies Pu connected in parallel. When the second pump set <NUM> includes at least two pump bodies Pu connected in parallel, a manner in which the at least two pump bodies Pu operate in parallel may be adopted, or a manner in which some of the pump bodies Pu operate and some of the pump bodies Pu are for backup may be adopted. With comprehensive consideration depending on of factors such as space layout size, system capacity, reliability and cost performance, energy-saving and fault-tolerant operation can be realized, that is, when one pump body Pu fails, the remaining pump body Pu can still meet all or more than <NUM>% of the performance of the system. At the same time, in order to further achieve the optimal energy efficiency of the system, the second pump set <NUM> can adopt a control manner such as fixed frequency operation, high or low speed operation, variable frequency operation, or fault-tolerant operation with at least two pump bodies Pu, which meets the cooling load operation requirement of the second cooling loop <NUM> and improves the fault tolerance performance and effective energy-saving strategies of the system.

The pump body is provided with a gas discharge valve AV to exhaust gas during system operation, thereby protecting the safe operation of the second pump set <NUM>. A check valve SV is arranged at the outlet of the pump body Pu to protect the pump body Pu. A pump body regulating valve PV is arranged at the inlet of the pump body Pu. The pump body regulating valve PV is closed quickly in response to the leakage problem of any one of the pump bodies Pu. A pump body Pu is cut off through a corresponding check valve SV and a corresponding pump body regulating valve PV. If the adopted pump body Pu is in a non-mechanical seal form, the setting of the pump body regulating valve PV can be omitted.

Optionally, a pressure stabilizing device SP is arranged at the inlet of the second pump set <NUM> for stabilizing the system pressure.

Optionally, a second filter is arranged at the inlet of the second pump set <NUM> to ensure the cleanliness of the system. In addition, the second filter has a liquid discharge function and can be used as a local liquid discharge point of the second pump set <NUM>.

Further, a plurality of second fluid branches <NUM> corresponding to the second heat-generating component <NUM> are arranged on the main path <NUM> of the second fluid pipeline <NUM>. The second heat-generating component <NUM> may be, for example, a generator. The bypass <NUM> is arranged downstream of the plurality of second fluid branches <NUM>. A second branch heat sink <NUM> is arranged on each second fluid branch <NUM>. A second heat dissipation unit <NUM> is further arranged on the second water return pipe 211b of the main path <NUM>. Since the flow and heat exchange of the plurality of second fluid branches <NUM> are evenly arranged, there is no need to provide relevant flow adjustment measures.

After passing through the second heat dissipation unit <NUM>, the second cooling medium enters the first heat exchanger <NUM>, absorbs the surplus cooling capacity in the first cooling loop <NUM> and realizes a balanced distribution of cooling capacity with the third cooling loop <NUM>, so as to avoid deviation in the heat dissipation calculation. After enough heat is reached, each second branch heat sink <NUM> and the second pump set <NUM> can be controlled by means of frequency conversion or high or low speed, so as to achieve the purpose of energy saving, or in the case where the cooling capacity is surplus and the wind condition satisfies a desired condition, over-generating of the generator system is achieved.

In addition, the main path <NUM> is further provided with a second total flow sensor F21 positioned at the inlet of the second pump set <NUM>, a second front total temperature sensor T21 positioned at the outlet of the second pump set <NUM>, a second middle total temperature sensor T22 positioned downstream of the plurality of second fluid branches <NUM>, and a second rear total temperature sensor T23 positioned at the inlet of the second heat dissipation unit <NUM>.

According to a temperature difference between the second middle total temperature sensor T22 and the second front total temperature sensor T21 and a flow rate of the second total flow sensor F21, a total dissipated heat loss of the second fluid pipeline <NUM> is obtained. In addition, a real-time loss change of the second cooling loop <NUM> according to the change of the ambient temperature may further be calculated, facilitating optimizing system accumulation data.

According to a temperature difference between the second rear total temperature sensor T23 and the second middle total temperature sensor T22 and a flow rate of the second middle total flow sensor F22, a to-be-dissipated heat loss of the second fluid pipeline <NUM> before entering the second heat dissipation unit <NUM> is obtained. According to the difference between the total dissipated heat loss and the to-be-dissipated heat loss, a waste heat transferred from the bypass <NUM> to the third cooling loop <NUM> is obtained.

Optionally, a second pressure monitoring device P2 is arranged at at least one of the inlet and the outlet of the second pump set <NUM>, downstream of the plurality of second fluid branches <NUM>, and upstream and downstream of the bypass <NUM>. Optionally, the second pressure monitoring device P2 includes a second pressure transmitter and a second pressure display device. The second pressure transducer is configured for local and remote monitoring of system operating conditions. The second pressure display device is configured for local fluid injection and operation and maintenance observation.

A second pressure monitoring device P2 is provided on the bypass <NUM> entering the second heat exchanger <NUM> to remotely and locally determine the blockage of the second heat exchanger <NUM> and the second cooling loop <NUM> for replacement and maintenance in advance. A second valve V2 is provided on upstream and downstream of the bypass <NUM>, which can cut the second heat exchanger <NUM> out of the system to meet maintenance requirements.

Optionally, a second valve V2 is arranged at at least one of the second water supply pipe 211a, the second water return pipe 211b, the outlet of the second pump set <NUM>, upstream and downstream of each second fluid branch <NUM>, upstream and downstream of the bypass <NUM> and the inlet of the second heat dissipation unit <NUM>.

The second cooling medium with high-temperature enters the second heat dissipation unit <NUM>. The second heat dissipation unit <NUM> is provided with a second gas discharge valve AV2 for high point and local gas discharge of the second heat dissipation unit <NUM>. A second valve V2 is arranged at the inlet of the second heat dissipation unit <NUM> and on the second water return pipe 211b. The second heat dissipation unit <NUM> can be switched out to facilitate replacement and maintenance of the second heat dissipation unit <NUM>.

The second valve V2 is arranged on each of the second water supply pipe 211a and the second return water pipe 211b of the second cooling loop <NUM>, which can easily switch out components on the main path <NUM> and the bypass <NUM> and the second branch heat sinks <NUM> on the plurality of second fluid branches <NUM>, and can also switch out the first heat exchanger <NUM> from the second cooling loop <NUM>. The second valve V2 is arranged on each second fluid branch <NUM>, which can switch out the second branch heat sink <NUM> from the second cooling loop <NUM>.

Optionally, a second liquid discharge valve LV2 is arranged on at least one of the second fluid pipeline <NUM>, each second fluid branch <NUM> and each second branch heat sink <NUM>. The second cooling medium in the first heat exchanger <NUM>, the second cooling loop <NUM> side and the second cooling unit <NUM> can be locally discharged through the second liquid discharge valve LV2.

Optionally, a second gas discharge valve AV2 is arranged at at least one of the second pump set <NUM>, the second fluid pipeline <NUM>, the second heat dissipation unit <NUM> and each second branch heat sink <NUM>. The second branch heat sink <NUM> is provided with the second gas discharge valve AV2 and the second liquid discharge valve LV2, which facilitates the gas discharge during the liquid injection process of the second branch heat sink <NUM> and the gas discharge during maintenance and replacement of the second branch heat sink <NUM>.

<FIG> shows a specific structure of the third cooling loop <NUM>. The third cooling loop <NUM> is an electrical cooling system, including a third fluid pipeline <NUM>, a third pump set <NUM>, a plurality of third branch heat sinks <NUM> connected in parallel and used for cooling the third heat-generating component <NUM>, and the third heat dissipation unit <NUM> taking away heat loss of all the components. The third cooling loop <NUM> further includes a heater, various functional valves, various sensors, pressure stabilizing devices and filters, so as to realize the normal, stable and maintainable operation of the third cooling loop <NUM>.

The third cooling medium enters from the third heat conduction channel of the first heat exchanger <NUM>. After the third pump set <NUM> makes the third cooling medium flow through the fifth heat conduction channel of the second heat exchanger <NUM>, the third cooling medium is transported to the plurality of first heat exchangers connected in parallel. After each branch heat exchanger exchanges heat with the third heat-generating component <NUM>, the third cooling medium converges and flows into the third heat dissipation unit <NUM> and flows into the third heat conduction channel of the first heat exchanger <NUM>.

Specifically, the third pump set <NUM> includes one pump body Pu or at least two pump bodies Pu connected in parallel. When the third pump set <NUM> includes at least two pump bodies Pu connected in parallel, a manner in which the at least two pump bodies Pu operate in parallel may be adopted, or a manner in which some of the pump bodies Pu operate and some of the pump bodies Pu are for backup may be adopted. With comprehensive consideration depending on of factors such as space layout size, system capacity, reliability and cost performance, energy-saving and fault-tolerant operation can be realized, that is, when one pump body Pu fails, the remaining pump body Pu can still meet all or more than <NUM>% of the performance of the system. At the same time, in order to further achieve the optimal energy efficiency of the system, the third pump set <NUM> can adopt a control manner such as fixed frequency operation, high or low speed operation, variable frequency operation, or fault-tolerant operation with at least two pump bodies Pu, which meets the cooling load operation requirement of the third cooling loop <NUM> and improves the fault tolerance performance and effective energy-saving strategies of the system.

The pump body is provided with a gas discharge valve AV to exhaust gas during system operation, thereby protecting the safe operation of the third pump set <NUM>. A check valve SV is arranged at the outlet of the pump body Pu to protect the pump body Pu. A pump body regulating valve PV is arranged at the inlet of the pump body Pu. The pump body regulating valve PV is closed quickly in response to the leakage problem of any one of the pump bodies Pu. A pump body Pu is cut off through a corresponding check valve SV and a corresponding pump body regulating valve PV If the adopted pump body Pu is in a non-mechanical seal form, the setting of the pump body regulating valve PV can be omitted.

Optionally, a pressure stabilizing device SP is arranged at the inlet of the third pump set <NUM> for stabilizing the system pressure.

Further, a third total flow sensor F3 is arranged upstream of the first section <NUM> of the third fluid pipeline <NUM>. A third front total temperature sensor T31 is arranged downstream of the first section <NUM>. A third heat dissipation unit <NUM> is arranged downstream of the second section <NUM>.

According to the number and the heat dissipation loss of the third heat-generating components <NUM>, a plurality of third fluid branches <NUM> in one-to-one correspondence with a plurality of third heat-generating components <NUM> are arranged on the second section <NUM>. The plurality of third heat-generating components <NUM> may be, for example, transformers, a converters, or an auxiliary transformer. Each third fluid branch <NUM> is provided with a third branch heat sink <NUM>. A third branch regulating valve VV3, a third branch temperature sensor TT3 and a third branch flow sensor FF3 are arranged downstream of each third fluid branch <NUM>.

A measured value of the third branch temperature sensor TT3 and a measured value of the third branch flow sensor FF3 are monitored, and an opening degree of the third branch regulating valve VV3 is controlled according to a target temperature value of each of the third heat-generating components <NUM> to adjust a flow rate of each of the third fluid branches <NUM>.

Further, a heater H is arranged downstream of the first section <NUM> of the third fluid pipeline <NUM>. The heater H is activated when the temperature of the third cooling medium is lower than a preset temperature and the second heat-generating component <NUM> is not activated.

Since the third heat-generating component <NUM> (that is, the converter) cannot be activated at extremely low temperature, it needs to be preheated by the cooling medium in the third cooling loop <NUM>. If the second heat-generating component <NUM> (that is, the generator) is not activated, the converter can heat the cooling medium by activating the heater H, so as to meet the preheating requirement before the converter is activated. If the generator is activated during this period, the heater H is turned off and the bypass regulating valve 212a is opened. The residual heat generated by the generator can heat the cooling medium in the second cooling loop <NUM>, and the cooling medium enters the second heat exchanger <NUM> through the bypass <NUM>. The third cooling medium with low-temperature exchanges heat with the second cooling medium with high-temperature in the second heat exchanger <NUM>, until the preset temperature at which the converter can be activated is reached. When the temperature of the third cooling medium reaches the preset temperature, the converter starts to operate, and the bypass regulating valve 212a is closed. By reusing the residual heat of the generator and activating the heater H as infrequently as possible, the self-consumption power of the system can be saved and the energy consumption of the system can be reduced.

Optionally, a third total temperature sensor T32 is arranged upstream of the second section <NUM>. An ON/OFF state of the heater H and the opening degree of the bypass regulating valve 212a are controlled according to a measured value of the third total temperature sensor T32, so as to meet the system requirements. By controlling the opening degree of the bypass regulating valve 212a, the flow rate of the high-temperature cooling medium entering the bypass <NUM> is adjusted, thereby gradually heating the third cooling medium.

The heated third cooling medium enters the third heat dissipation unit <NUM>, and then enters the first heat exchanger <NUM> again after heat dissipation, absorbs the surplus cooling capacity in the first cooling loop <NUM>, and at the same time realizes balanced distribution of heat with the second cooling loop <NUM> and achieves the effect of energy saving of the third pump set <NUM> or over-generating.

Further, a third rear total temperature sensor T33 is further arranged downstream of the second section <NUM>. According to a temperature difference between the third rear total temperature sensor T33 and the third front total temperature sensor T31 and a flow rate of the third total flow sensor F3, an exchanged heat of the third cooling medium after flowing through the first heat exchanger <NUM> is obtained. According to a temperature difference between the third rear total temperature sensor T33 and the third middle total temperature sensor T32 and a flow rate of the third total flow sensor F3, a total generated heat of the third heat-generating component <NUM> is obtained.

Optionally, a third valve V3 is arranged at at least one of upstream and downstream of the first section <NUM>, upstream and downstream of the second section <NUM>, upstream and downstream of each of the third fluid branches <NUM> and an inlet of the third heat dissipation unit <NUM>.

Optionally, a third liquid discharge valve LV3 is arranged on at least one of the first section <NUM> and each of the third fluid branches <NUM>. Optionally, a third filter is arranged at the inlet of the third pump set <NUM> to ensure the cleanliness of the system. In addition, the first filter has a liquid discharge function and can be used as a local liquid discharge point of the first pump set <NUM>.

Optionally, a third gas discharge valve AV3 is arranged on at least one of the third pump set <NUM>, the third heat dissipation unit <NUM>, and each of the third fluid branches <NUM>.

The functions of the third valve V3, the third liquid discharge valve LV3 and the third gas discharge valve AV3 are similar to those of the aforementioned second valve V2, the second liquid discharge valve LV2 and the second gas discharge valve AV2, respectively, and will not be repeated.

Optionally, a third pressure monitoring device P3 is arranged at at least one of an inlet and an outlet of the third pump set <NUM>, downstream of the first section <NUM>, upstream of the second section <NUM>, and upstream and downstream of each of the third fluid branches <NUM>. Optionally, the third pressure detection device P3 includes a third pressure transducer and a third pressure display device, The third pressure transducer is configured for local and remote monitoring of the system operating condition. The third pressure display device is configured for local fluid injection and operation and maintenance observation.

Therefore, in the cooling system provided by the embodiment of the present application, the first cooling loop <NUM>, the second cooling loop <NUM> and the third cooling loop <NUM> form respective closed-loop circulations through pipelines, valves, temperature sensors, flow sensors, pressure transducers and the like. Under the condition that each cooling loop operates independently, the first heat exchanger <NUM> and the second heat exchanger <NUM> conduct heat transfer but not mass transfer in each cooling loop, so as to realize the appropriate distribution of multiple system cooling capacity, and satisfy the heat dissipation requirements of each heat-generating component. At the same time, a regulating valve is arranged in the cooling loop to adjust the flow rate of each cooling loop according to the load requirement of each heat-generating component. Under appropriate ambient temperature conditions, when the temperature control requirements of the first heat-generating component <NUM> of the first cooling loop <NUM> are satisfied, the surplus cooling capacity is distributed to the second cooling circuit <NUM> and the third cooling circuit <NUM>. A part of the residual heat carried by the second cooling loop <NUM> is used for heating the third cooling loop <NUM> through the bypass <NUM>, reducing the power consumption caused by the electric heating of the third cooling loop <NUM>. While the heat dissipation requirements are satisfied, through thermal coupling between cooling loops in a manner in which these cooling loops are isolated from one another, appropriate distribution of cooling capacity and appropriate application of waste heat can be realized, thereby realizing balanced utilization of cold capacity and heat capacity and reducing system power consumption.

In addition, the wind-driven generator system provided by the embodiments of the present application adopts the aforementioned cooling system, which can effectively record the system loss and the heat transfer direction during the operation of the generator system. At the same time, combined with the ambient temperature, more appropriate component selection can be found out, providing sufficient data record basis for the subsequent evaluation of the reliability of wind-driven generator system.

In addition, the cooling system according to the above-described exemplary embodiments can be applied to various electrical apparatuses requiring heat dissipation, such as but not limited to wind-driven generator systems.

Claim 1:
A cooling system, comprising a first cooling loop (<NUM>), a second cooling loop (<NUM>), a third cooling loop (<NUM>), a first heat exchanger (<NUM>) and a second heat exchanger (<NUM>), wherein
the first cooling loop (<NUM>) comprises a first fluid pipeline (<NUM>) for cooling a first heat-generating component (<NUM>) and a first pump set (<NUM>), and the first pump set (<NUM>) is configured to cause a first cooling medium to circulate within the first fluid pipeline (<NUM>);
the second cooling loop (<NUM>) comprises a second fluid pipeline (<NUM>) for cooling a second heat-generating component (<NUM>) and a second pump set (<NUM>), the second fluid pipeline (<NUM>) comprises a main path (<NUM>) and a bypass (<NUM>), and the second pump set (<NUM>) is configured to cause a second cooling medium to circulate within the main path (<NUM>) or within the main path (<NUM>) and the bypass (<NUM>);
the third cooling loop (<NUM>) comprises a third fluid pipeline (<NUM>) for cooling a third heat-generating component (<NUM>) and a third pump set, the third pump set is configured to cause a third cooling medium to circulate within the third fluid pipeline (<NUM>), and the third fluid pipeline (<NUM>) communicates with both the first heat exchanger (<NUM>) and the second heat exchanger (<NUM>), wherein the third heat-generating component (<NUM>) generates more heat than the first heat-generating component (<NUM>), but generates less heat than the second heat-generating component (<NUM>);
the first heat exchanger (<NUM>) is configured to thermally couple the first cooling medium, the second cooling medium and the third cooling medium to one another in a manner in which the first cooling medium, the second cooling medium and the third cooling medium are isolated from one another;
the second heat exchanger (<NUM>) is configured to thermally couple the second cooling medium to the third cooling medium through the bypass (<NUM>) in a manner in which the second cooling medium and the third cooling medium are isolated from each another.