JP2022120320A - Compressor and method of controlling compressor - Google Patents

Abstract

To provide a technology capable of suppressing a rise of inner pressure of a motor storage portion by determining a maintenance timing of a release pipe in a compressor.SOLUTION: A compressor is equipped with a rotator for compressing and feeding a fluid, a motor that drives the rotator, a motor storage portion for storing the motor, a release pipe for communicating the inside and outside of the compressor including the motor storage portion, and a maintenance timing determining portion that determines a maintenance timing of the release pipe by using a first value related to a pressure loss of the release pipe.SELECTED DRAWING: Figure 5

Description

The present disclosure relates to compressors and compressor control methods.

A fuel cell system is known in which air is supplied to a cathode of a fuel cell stack using a compressor equipped with a motor for rotating a turbine (for example, Patent Document 1).

JP 2009-301845 A

A compressor is sometimes provided with a pipeline for opening each part in the compressor to the atmosphere in order to suppress pressure rise in each part in the compressor. For example, if the pressure loss in the pipeline increases due to adhesion of foreign matter to the pipeline for venting to the atmosphere, the internal pressure of the compressor rises, causing a problem of oil leakage to the outside of the compressor.

The present disclosure can be implemented as the following forms.

(1) According to one aspect of the present disclosure, a compressor is provided. This compressor includes a rotating body for compressing and sending out a fluid, a motor for driving the rotating body, a motor accommodating portion for accommodating the motor, an interior of the compressor including the motor accommodating portion, and an external portion. and a maintenance timing determination unit that determines maintenance timing for the open pipe using a first value related to pressure loss in the open pipe.
According to the compressor of this aspect, by determining the maintenance timing of the open pipe using the first value related to the pressure loss of the open pipe, the rise of the pressure loss of the open pipe is suppressed, and the internal pressure of the compressor is excessive. can be suppressed.
(2) In the compressor of the above aspect, the first value is an index pre-associated with each operating point of the compressor, and is the amount of change in pressure loss per unit period in the open pipe. It may be a related index. The maintenance timing determining section may determine the maintenance timing of the open pipe using a second value obtained by multiplying the first value by the driving period of the compressor at the operating point.
According to the compressor of this aspect, it is possible to estimate the amount of increase in the pressure loss of the open pipe based on the driving conditions of the compressor, and to more accurately determine the maintenance timing of the open pipe.
(3) In the compressor of the above aspect, the maintenance timing determination unit calculates the second value for each operating point for driving the compressor, and integrates the calculated second value for each operating point. It may be determined that it is time to perform maintenance on the open pipe when a third value, which is the sum of the values obtained, exceeds a predetermined first threshold value.
According to the compressor of this aspect, by calculating the second value for each operating point of the compressor, it is possible to more accurately determine the maintenance timing of the open pipe.
(4) In the compressor of the above aspect, the open tube may be provided with a replaceable filter section. The maintenance timing determination unit may notify that replacement of the filter unit is necessary when determining that it is time for maintenance of the open tube.
According to the compressor of this form, by urging the user of the compressor to replace the filter portion, it is possible to reduce or prevent the pressure rise in the compressor at an early stage.
(5) In the compressor of the aspect described above, the maintenance timing determining section may store a map that associates the first value with the operating point.
According to the compressor of this aspect, by using the map, it is possible to reduce the processing load of the maintenance time determining section.
(6) In the compressor of the above aspect, the first value may be an accumulated driving period of the compressor. The maintenance timing determination section may determine that it is time for maintenance of the open pipe when the accumulated driving period of the compressor exceeds a predetermined period.
According to the compressor of this aspect, it is possible to reduce the processing load of the maintenance timing determination unit for determining the maintenance timing of the open pipe.
(7) The compressor of the above aspect, further comprising a replaceable filter section provided in the open pipe, and a differential pressure sensor for detecting the differential pressure of the filter section as the first value. good. The maintenance timing determination unit may determine that it is time for maintenance of the open pipe when the differential pressure of the filter unit obtained from the differential pressure sensor exceeds a predetermined second threshold value.
According to the compressor of this aspect, the differential pressure of the filter portion is detected using the sensor, so that the maintenance timing of the open pipe can be determined more accurately.
The present disclosure can also be implemented in various forms other than compressors. For example, a fuel cell system with a compressor, a fuel cell vehicle with a compressor, a method of compressing gas with a compressor, a method of manufacturing a compressor, a method of controlling the compressor, a computer program for realizing the control method, and a non-temporary recording of the computer program It can be realized in the form of a recording medium or the like.

Explanatory drawing which shows the structure of a fuel cell system. Explanatory drawing which shows the internal structure of an air compressor. FIG. 4 is an explanatory diagram showing a compressor map showing performance characteristics of an air compressor; Explanatory drawing which shows a mist amount map. 4 is a flow chart showing control for determining maintenance timing of a breather pipe. 4 is a graph showing the relationship between the pressure loss of the breather pipe and the amount of accumulated mist.

A. First embodiment:
FIG. 1 is an explanatory diagram showing the configuration of a fuel cell system 200. As shown in FIG. The fuel cell system 200 is mounted, for example, on a fuel cell vehicle that uses the fuel cell 20 as a drive source. The fuel cell system 200 uses power generated by the fuel cell 20 to drive various devices included in the load. The fuel cell system 200 has a fuel cell 20 , a control device 60 , an oxidizing gas supply/discharge system 30 , and a fuel gas supply/discharge system 50 . The fuel cell system 200 may further include a coolant circulation system that circulates a coolant through the fuel cell 20 to adjust the temperature of the fuel cell 20, and a secondary cell that functions together with the fuel cell 20 as a power source for the load. good.

The fuel cell 20 has a stack structure in which a plurality of fuel cells are stacked, each having a membrane electrode assembly (MEA) in which both electrodes of an anode and a cathode are joined to both sides of an electrolyte membrane. The fuel cell 20 is a polymer electrolyte fuel cell that generates power by being supplied with hydrogen gas and air as reaction gases, and drives a load using the generated power. The load includes, for example, a drive motor that generates driving force for the fuel cell vehicle, a heater that is used for air conditioning in the fuel cell vehicle, and the like. The fuel cell 20 includes an anode supply port 251 for supplying hydrogen gas as anode gas to the anode, an anode discharge port 252 for discharging hydrogen gas from the anode, and an anode gas for supplying air as oxidizing gas to the cathode. and a cathode outlet 232 for exhausting air from the cathode. The fuel cell 20 is not limited to solid polymer type fuel cells, and may be of various types such as phosphoric acid type, molten carbonate type, and solid oxide type. The fuel cell system 200 may be used not only for fuel cell vehicles, but also for household power sources, stationary power generation, and the like.

The fuel gas supply and discharge system 50 includes a fuel gas supply system 50A having an anode gas supply function, a fuel gas discharge system 50C having an anode gas discharge function, and a fuel gas circulation system 50B having an anode gas circulation function. there is The anode gas supply function means the function of supplying anode gas containing fuel gas to the anode of the fuel cell 20 . The anode gas discharge function means a function of discharging anode off-gas, which is exhaust gas discharged from the anode of the fuel cell 20, to the outside. The anode gas circulation function means a function of circulating hydrogen contained in the anode off-gas within the fuel cell system 200 .

The fuel gas supply system 50A includes an anode supply pipe 501, a fuel gas tank 51, an on-off valve 52, a regulator 53, and an injector . The anode supply pipe 501 connects the fuel gas tank 51 , which is the supply source of the anode gas, and the anode supply port 251 of the fuel cell 20 . The fuel gas tank 51 contains, for example, high pressure hydrogen of 10 to 70 MPa. The on-off valve 52 is an electric valve or an electromagnetic valve whose opening can be changed according to a control signal from the control device 60 . The on-off valve 52 is provided near the outlet of the fuel gas tank 51 and adjusts the amount of hydrogen supplied to the downstream side. The regulator 53 is a pressure reducing valve that adjusts the pressure of hydrogen upstream of the injector 54 under the control of the control device 60 . The injector 54 is controlled by the control device 60 and electromagnetically drives the open/close valve according to the set driving cycle and valve opening time to adjust the supply amount of the anode gas.

The fuel gas circulation system 50B separates the anode off-gas discharged from the anode of the fuel cell 20 into a gas component and a liquid component, and circulates it to the anode supply pipe 501 . The fuel gas circulation system 50 B has an anode circulation pipe 502 , a gas-liquid separator 57 and a circulation pump 55 . One end of the anode circulation pipe 502 is connected to the anode discharge port 252 of the fuel cell 20 and the other end is connected to the anode supply pipe 501 . The anode circulation pipe 502 is equipped with a circulation pump 55 and a gas-liquid separator 57 . The circulation pump 55 is driven and controlled by the control device 60 and sends out the anode off-gas that has flowed into the anode circulation pipe 502 in the direction from the anode discharge port 252 toward the anode supply pipe 501 . A gas-liquid separator 57 is provided between the circulation pump 55 and the anode outlet 252 . The gas-liquid separator 57 separates the anode off-gas containing water vapor, nitrogen, and hydrogen into a gas component and a liquid component, and stores the liquid component.

The fuel gas discharge system 50C discharges the anode off-gas and the liquid water stored in the gas-liquid separator 57 to the outside. The fuel gas exhaust system 50</b>C has an anode exhaust pipe 504 and an exhaust drain valve 58 . One end of the anode discharge pipe 504 is connected to the discharge port of the gas-liquid separator 57 , and the other end is connected between the cathode discharge port 232 and the exhaust gas discharge port 309 in the cathode discharge pipe 306 . The anode discharge pipe 504 discharges the waste water from the gas-liquid separator 57 and part of the anode off-gas passing through the gas-liquid separator 57 from the fuel gas supply and discharge system 50 . The exhaust/drain valve 58 is a diaphragm valve whose opening/closing is controlled by the controller 60 , and opens/closes the flow path of the anode exhaust pipe 504 . When the exhaust drain valve 58 is opened, the liquid water and the anode off-gas stored in the gas-liquid separator 57 are discharged into the atmosphere through the cathode discharge pipe 306 .

The oxidant gas supply/discharge system 30 includes an oxidant gas supply system 30A having a cathode gas supply function, and an oxidant gas discharge system 30B having a cathode gas discharge function and a cathode gas bypass function. The cathode gas supply function means the function of supplying oxygen-containing air as cathode gas to the cathode of the fuel cell 20 . The cathode gas discharge function means a function of discharging cathode off-gas, which is exhaust gas discharged from the cathode of the fuel cell 20, to the outside. The cathode gas bypass function means a function of discharging part of the supplied cathode gas to the outside without supplying it to the fuel cell 20 .

The oxidant gas supply system 30A has a cathode gas supply function, and supplies the cathode of the fuel cell 20 with air as an oxidant gas. The oxidizing gas supply system 30A includes a cathode supply pipe 302, an atmospheric pressure sensor 32, an air cleaner 31, an air flow meter 34, an air compressor 100, an intercooler 35, a discharge side pressure sensor 38, an inlet valve 36, have

The cathode supply pipe 302 is connected to the cathode supply port 231 of the fuel cell 20 and functions as an air supply channel for the cathode of the fuel cell 20 . The air cleaner 31 is provided on the air inlet side of the air compressor 100 in the cathode supply pipe 302 , that is, on the upstream side, and removes foreign matter from the air supplied to the fuel cell 20 .

The atmospheric pressure sensor 32 measures atmospheric pressure. The atmospheric pressure sensor 32 is arranged upstream of the air cleaner 31 in the cathode supply pipe 302 . The airflow meter 34 measures the flow rate of the oxidizing gas sucked into the air compressor 100 . The airflow meter 34 is arranged upstream of the air compressor 100 in the cathode supply pipe 302 . The discharge-side pressure sensor 38 measures the pressure of air discharged from the air compressor 100 as oxidizing gas. The measured value of the discharge side pressure sensor 38 corresponds to the pressure inside the cathode of the fuel cell 20 . The discharge-side pressure sensor 38 is arranged downstream of the air compressor 100 in the cathode supply pipe 302 . Measurement values measured by the various sensors 32 , 34 , 38 are transmitted to the control device 60 . Furthermore, a flow rate sensor that measures the flow rate of air supplied to the fuel cell 20 may be provided near the cathode supply port 231 of the fuel cell 20 .

Air compressor 100 is provided between air cleaner 31 and fuel cell 20 in cathode supply pipe 302 . The air compressor 100 compresses the air taken in through the air cleaner 31 and sends it to the cathode. As the air compressor 100, for example, a centrifugal turbo compressor is used. The air compressor 100 is driven and controlled by the control device 60, and controls the flow rate of the air flowing through the fuel cell 20 and the flow rate of the air discharged from the cathode discharge pipe 306 in cooperation with the bypass valve 39 and the outlet valve 37. . An axial turbo compressor may be used as the air compressor 100 .

Intercooler 35 is provided between air compressor 100 and cathode supply port 231 in cathode supply pipe 302 . The intercooler 35 cools the cathode gas that has been compressed by the air compressor 100 and heated to a high temperature. The inlet valve 36 is an on-off valve that mechanically opens when the cathode gas with a predetermined pressure flows. Inlet valve 36 controls the inflow of cathode gas to the cathode of fuel cell 20 .

The oxidizing gas discharge system 30B has a cathode offgas discharge function, and includes a cathode discharge pipe 306, a bypass pipe 308, a bypass valve 39, an outlet valve 37, and an exhaust gas discharge port 309. The cathode discharge pipe 306 is a cathode off-gas discharge channel, one end of which is connected to the cathode discharge port 232 of the fuel cell 20 . The cathode exhaust pipe 306 guides the exhaust gas of the fuel cell 20, including the cathode off-gas, to the exhaust gas exhaust port 309, which is the other end of the cathode exhaust pipe 306, and discharges it to the atmosphere. Exhaust gas discharged from the cathode discharge pipe 306 into the atmosphere includes not only cathode off-gas but also anode off-gas from the anode discharge pipe 504 and air flowing out from the bypass pipe 308 .

The outlet valve 37 is provided near the cathode outlet 232 in the cathode outlet pipe 306 . More specifically, the outlet valve 37 is arranged in the cathode discharge pipe 306 closer to the fuel cell 20 than the connection position between the cathode discharge pipe 306 and the bypass pipe 308 . As the outlet valve 37, for example, an electromagnetic valve or an electric valve can be used. The controller 60 adjusts the back pressure of the cathode of the fuel cell 20 by adjusting the opening of the outlet valve 37 .

A bypass pipe 308 is a pipe line that connects the cathode supply pipe 302 and the cathode discharge pipe 306 without going through the fuel cell 20 . A bypass valve 39 is provided in the bypass pipe 308 . As the bypass valve 39, for example, an electromagnetic valve or an electric valve can be used. When bypass valve 39 is opened, at least part of the cathode gas flowing through cathode supply pipe 302 flows into cathode exhaust pipe 306 . The control device 60 adjusts the flow rate of the cathode gas flowing into the bypass pipe 308 by adjusting the degree of opening of the bypass valve 39, and the discharge amount of the air that flows through the cathode discharge pipe 306 and is discharged from the exhaust gas discharge port 309. to adjust.

The control device 60 is, for example, an ECU (Electronic Control Unit), and includes a microprocessor 62 that executes logic operations, and a memory 64 such as ROM and RAM. The memory 64 stores a compressor map 642, a mist amount map 644, a mist accumulation amount 646, and a control program (not shown). Compressor map 642 is a map that indicates the operating characteristics of air compressor 100 . The mist amount map 644 is a map showing the correspondence relationship between the operating point of the air compressor 100 and the adhesion speed of the oil mist that adheres to the breather pipe of the air compressor 100 . The amount of accumulated mist 646 is the total value of the amount of oil mist adhering to the breather pipe calculated by the microprocessor 62 . The control device 60 performs various controls of the fuel cell system 200 including power generation of the fuel cell 20 and drive control of the air compressor 100 by the microprocessor 62 developing and executing a control program stored in the memory 64 . and a maintenance timing determination unit that performs maintenance timing determination control for determining the maintenance timing of the breather pipe 180 . In addition to being provided in fuel cell system 200, control device 60 may be mounted in air compressor 100, or may be mounted in a fuel cell vehicle in which fuel cell system 200 is mounted.

FIG. 2 is an explanatory diagram showing the internal configuration of the air compressor 100 of this embodiment. Air compressor 100 includes a rotating body portion 120 , an oil reservoir portion 110 , an oil pump 112 , a motor portion 160 , a mechanical seal 170 and a breather pipe 180 .

The rotating body section 120 includes a rotating body 121 and a rotating body accommodating section 122 that accommodates the rotating body 121 . As the rotating body 121 rotates, the gas supplied from the cathode supply pipe 302 is compressed in the rotating body accommodating portion 122 and sent to the fuel cell 20 . Although an impeller is used as the rotating body 121 in this embodiment, a gear may be used, for example.

Motor section 160 includes motor 130 , bearing 141 , bearing cases 140 and 144 , and motor housing section 150 . The motor 130 is an electric motor that converts electric power into rotational output, and drives the rotating body 121 . The motor 130 includes a motor rotating shaft 131 , a rotor 132 integrally formed with the motor rotating shaft 131 , and a stator 134 having coils 133 . The motor 130 is energized and controlled by the control device 60 . The rotor 132 has magnets on its surface and rotates integrally with the motor rotating shaft 131 . Stator 134 cooperates with rotor 132 to rotate rotor 132 . The control device 60 controls the rotation speed of the motor 130 according to the power generated by the fuel cell 20 . Thereby, the air compressor 100 generates supercharging pressure for supplying air necessary for power generation of the fuel cell 20 .

The bearing 141 is a ball bearing having a plurality of balls, and supports the motor rotating shaft 131 in a rotatable state. The bearing 141 is housed in a bearing case 140 located near the rotating body portion 120 and a bearing case 144 located away from the rotating body portion 120 . Note that the bearing 141 is not limited to a ball bearing and may be a needle bearing.

The mechanical seal 170 is a seal portion that includes a stationary ring 172 and a rotary ring 174 . The fixed ring 172 is arranged between the bearing 141 and the rotor portion 120 and fixed to the motor housing portion 150 . The rotary ring 174 is fixed to the motor rotary shaft 131 . The mechanical seal 170 realizes high-speed rotation of the motor rotating shaft 131 and seals oil in the motor accommodating portion 150 from leaking into the rotor accommodating portion 122 from between the fixed ring 172 and the rotary ring 174. do.

The oil storage part 110 is a tank that stores and cools oil. Oil pump 112 is a pump that supplies oil from oil storage portion 110 to motor housing portion 150 . In the air compressor 100 of the present embodiment, when the fuel cell 20 is requested to generate power, the control device 60 starts rotating the motor 130 . The oil pump 112 is driven by utilizing the rotation of the motor 130 , and the supply of oil to the motor housing portion 150 by the oil pump 112 is started. Specifically, oil pump 112 sucks up oil from oil reservoir 115 in oil reservoir 110 through pipe 116 and supplies the oil to motor housing 150 through oil circulation path 153, which will be described later.

The motor housing portion 150 is a housing that houses the motor 130 and the bearing cases 140 and 144 . An oil circulation path 153 for circulating oil from the oil reservoir 110 into the motor housing portion 150 is formed in the motor housing portion 150 . The oil circulation path 153 branches into a plurality of oil circulation paths 153a, 153b, 153c and 153d. The oil circulation paths 153 a and 153 b are positioned vertically above the motor 130 . The oil flowing out from the oil circulation paths 153 a and 153 b into the motor housing portion 150 cools the motor 130 . The oil circulation path 153 c is positioned vertically above the bearing case 140 . The oil circulation path 153 d is positioned vertically above the bearing case 144 . An oil damper is formed between the motor housing portion 150 and the bearing case 140 by filling the gap between the motor housing portion 150 and the bearing case 140 with the oil supplied from the oil circulation path 153c. Similarly, an oil damper is formed between the motor housing portion 150 and the bearing case 144 by filling the gap formed between the motor housing portion 150 and the bearing case 144 with oil supplied from the oil circulation path 153d. It is formed. The oil that has flowed into the motor housing portion 150 may become mist due to temperature rise in the motor housing portion 150 or contact with the motor rotating shaft 131 .

Breather pipe 180 communicates the inside and outside of oil reservoir 110 . Breather pipe 180 functions as an open pipe that suppresses an increase in the internal pressure of air compressor 100 including motor accommodating portion 150 and oil circulation path 153 by opening oil storage portion 110 to the atmosphere. The breather pipe 180 includes a mist collection section 182 and a filter section 184 . The mist collector 182 has a metal mesh. The mist collection unit 182 collects the oil mist contained in the fluid flowing in the breather pipe 180 by adhering it to a metal mesh. When the oil adhering to the mist collecting portion 182 accumulates to a certain amount, it moves in the breather pipe 180 in the direction of gravity due to its own weight and is collected in the oil storing portion 110 .

The filter part 184 is a filter arranged near the outlet of the breather pipe 180 . As the filter part 184, a detachable so-called cartridge type or spin-on type filter, filter cloth, non-woven fabric, or the like can be used. Filter portion 184 removes foreign matter contained in the fluid flowing through breather pipe 180 . More specifically, the filter unit 184 suppresses entry of external foreign matter and liquid droplets into the breather pipe 180 in the vicinity of the discharge port of the breather pipe 180, and prevents fluid flowing through the breather pipe 180. The gas component is passed to the outside air, and the liquid component remaining in the fluid, such as oil mist, is formed into droplets and adhered. The amount of oil mist adhering to breather pipe 180 and filter portion 184 (hereinafter also simply referred to as “mist amount”) affects the pressure loss of breather pipe 180 . For example, if an excessive amount of oil mist adheres to breather pipe 180 and filter portion 184, the pressure loss in breather pipe 180 increases. As a result, the fluid in oil storage portion 110 cannot flow to the outside, and the internal pressure of each portion of air compressor 100 including motor housing portion 150 and oil circulation path 153 increases. If the internal pressure of the air compressor 100 rises excessively, various parts of the air compressor 100 may be damaged, and oil may flow out from the motor accommodating portion 150 . Therefore, it is preferable to replace the filter portion 184 before the pressure loss of the breather pipe 180 excessively increases.

FIG. 3 is an explanatory diagram showing a compressor map 642 showing performance characteristics of the air compressor 100 of this embodiment. In FIG. 3, the vertical axis represents the pressure ratio of the air compressor 100, and the horizontal axis represents the flow rate of air discharged from the air compressor 100 (hereinafter also referred to as "discharge flow rate"). FIG. 3 shows the operating characteristics of the air compressor 100 when the bypass valve 39 is closed. As shown in FIG. 3, the operating point of the air compressor 100 is predetermined by a combination of the discharge flow rate and the pressure ratio. FIG. 3 shows an example of a plurality of equal rotation speed lines L1 with different rotation speeds, a surge line L4, and a stall line L5. A region where the discharge flow rate is lower than that of the surge line L4 is a surging region. The surging region is a region of operating points where surging can occur in air compressor 100 . A surge line L4 is a line representing the limit of the operating point range that is not included in the surging region. The pressure ratio is the ratio of the air pressure on the discharge side (hereinafter also referred to as "discharge pressure") to the air pressure on the suction side of the air compressor 100 (hereinafter also referred to as "suction pressure"). The control device 60 calculates the target air discharge flow rate using the following equation (1). The discharge flow rate of equation (1) is also called a "corrected flow rate."

The flow rate (NL/min) is the mass flow rate of the air taken in by the air compressor 100 and is determined using the target value of the required current of the fuel cell 20 . The target value of the required current of the fuel cell 20 is calculated, for example, based on detection signals from an accelerator opening sensor, a vehicle speed sensor, etc. of the fuel cell vehicle in which the fuel cell system 200 is installed. The control device 60 determines the flow rate for the requested current, for example, by referring to a map showing the correspondence between the flow rate and the requested current. The intake air temperature is, for example, a measured value of an outside air temperature sensor (not shown). The standard air temperature is the reference temperature of the intake air, and is set to a predetermined value such as 25°C. The intake air pressure is the pressure of air taken in by the air compressor 100 and is the measured value of the atmospheric pressure sensor 32 . The standard air pressure is a reference pressure for the air sucked by the air compressor 100, and is set to a predetermined value such as standard air pressure. Note that the discharge flow rate is not limited to the case of using the corrected flow rate calculated by the above formula (1). For example, when a flow sensor is provided near the cathode supply port 231, the detection result of the flow sensor may be used as the ejection flow rate.

FIG. 4 is an explanatory diagram showing the mist amount map 644. As shown in FIG. The mist amount map 644 is a map in which each operating point on the compressor map 642 is associated in advance with the amount of oil mist adhering to the filter section 184 per unit period (hereinafter also referred to as "mist adhesion speed"). is. The mist adhesion speed for each operating point is determined in advance through experiments such as tests using the air compressor 100 and the fuel cell system 200 . The deposition rate for each operating point may be determined theoretically or by simulation. The mist deposition speed is an index related to the amount of change in pressure loss per unit period in breather pipe 180 and is included in one aspect of the “first value” related to pressure loss in breather pipe 180 . After determining the operating point of the air compressor 100, the control device 60 uses the mist amount map 644 shown in FIG. 4 to detect the mist adhesion speed at the operating point. Note that the mist adhesion speed may be calculated for each operating point without using the mist amount map 644 .

In the present embodiment, the mist adhesion speed is determined for each predetermined region including a plurality of operating points, as indicated by mist adhesion speed V1 to mist adhesion speed V3 in FIG. The predetermined area can be arbitrarily set using the width between the constant rotation speed lines L1 and the width between the discharge flow rates, as shown as areas A1 to A3 in FIG. 4, for example. By setting one mist deposition speed for each predetermined area, the load on the processing by the microprocessor 62 and the storage area of the memory 64 associated with the calculation of the amount of mist can be reduced. From the viewpoint of improving the accuracy of determining the maintenance timing of the breather pipe 180, the predetermined area is preferably of a size such that the mist adhesion speed at each operating point included in the area is the same. From the viewpoint of reducing the load on 60, it is preferable to set in a wide area.

The mist adhesion speed increases as the position in the compressor map 642 is closer to the surging region. More specifically, the mist adhesion speed increases as the rotation speed of the air compressor 100 increases and the discharge flow rate decreases. In this embodiment, the mist adhesion speed V1 to the mist adhesion speed V3 are set to an operating point at which the mist adhesion speed reaches the maximum value in the region in order to reliably prevent the problem of an excessive increase in the pressure loss of the breather pipe 180. That is, it is set using the mist adhesion speed at the operating point where the air compressor 100 has the highest rotational speed and the lowest discharge flow rate within the range.

Using the mist amount map 644, the controller 60 acquires the mist adhesion speed at the determined operating point and the drive time of the air compressor 100 for each operating point, as will be described later. The controller 60 multiplies the mist adhesion speed associated with the operating point by the driving time of the air compressor 100 to calculate the mist adhesion amount for each operating point. The mist adhesion amount means the amount of oil mist that adheres to the filter portion 184 by driving the air compressor 100 at one operating point. The mist adhesion amount is also referred to as a "second value". In the example of FIG. 4, the air compressor 100 is driven at the operating point M1 for the time t1, driven at the operating point M2 for the time t2, and driven at the operating point M3 for the time t3 after starting. As shown in FIG. 4, the operating point M1 belongs to a region A1 with a mist adhesion speed of V1, and the amount of mist adhesion at the operating point M1 is calculated by the formula V1·t1. The operating point M2 belongs to the area A2 in which the mist adhesion speed is V2, and the operating point M3 belongs to the area A3 in which the mist adhesion speed is V3. The control device 60 calculates the total value obtained by accumulating the amount of mist adhesion at each operating point, that is, the calculation result of V1·t1+V2·t2+V3·t3, and calculates the mist adhesion generated by driving the air compressor 100 at each of the operating points M1 to M3. The total value of the amount (hereinafter also referred to as "mist accumulation amount"). The amount of accumulated mist is also called a "third value".

FIG. 5 is a flowchart showing control for determining maintenance timing of breather pipe 180 executed by control device 60 . This flow is a flowchart corresponding to one operating point of the air compressor 100, and is executed, for example, each time the required power of the fuel cell 20 is changed or the required operating point of the air compressor 100 is changed. This flow may be started when the fuel cell system 200 is activated, and may be repeatedly executed, for example, at regular intervals such as every few seconds or minutes.

In step S10, the control device 60 calculates the discharge flow rate and pressure ratio that satisfy the required electric power of the fuel cell 20. FIG. In step S20, the controller 60 sets a required operating point based on the target flow rate, which is the target value of the discharge flow rate of the air compressor 100, and the target pressure ratio, which is the target value of the pressure ratio before and after compression by the air compressor 100. do. In step S22, the control device 60 adjusts the opening of the outlet valve 37 and the rotation speed of the air compressor 100 so as to achieve the target flow rate and target pressure ratio at the set required operating point. Accordingly, the air compressor 100 supplies air to the fuel cell 20 at the target flow rate and target pressure ratio. The control device 60 starts counting the elapsed time from the start of driving at the required operating point using an internal clock, time server, or the like.

In step S30, the controller 60 uses the mist amount map 644 to acquire the mist adhesion speed corresponding to the set required operating point. In this embodiment, the control device 60 reads out the region to which the required operating point belongs from the mist amount map 644 and acquires the mist adhesion speed set for that region. In step S40, the control device 60 acquires the counted time from the start of driving at the requested operating point to the end of driving as the driving time at the requested operating point along with the completion of driving at the requested operating point. In step S50, the control device 60 calculates the mist adhesion amount, which is the second value. More specifically, the control device 60 multiplies the mist adhesion speed acquired in step S30 by the driving time at the required operating point acquired in step S40 to calculate the mist adhesion amount at the required operating point.

In step S60, the control device 60 adds the mist adhesion amount calculated in step S50 to the mist accumulation amount 646 stored in the memory 64 to calculate the mist accumulation amount. The accumulated mist amount 646 stored in the memory 64 is a total value obtained by accumulating the mist adhesion amount for each flow, and corresponds to the total mist adhesion amount up to the completion of the previous flow. In step S70, it is determined whether or not the calculated mist accumulation amount 646 is greater than a predetermined first threshold. The predetermined first threshold used in step S70 is set using the corresponding relationship between the amount of accumulated mist and the pressure loss of breather pipe 180 .

FIG. 6 is a graph showing the correspondence relationship between the pressure loss of breather pipe 180 and the amount of accumulated mist. FIG. 6 shows the first threshold BT. The correspondence shown in FIG. 6 can be obtained from test results, simulation results, etc., using the air compressor 100 and the fuel cell system 200, for example. As shown in FIG. 6, the pressure loss of the breather pipe 180 tends to increase as the amount of accumulated mist increases. The first threshold BT is set using a mist accumulation amount that can reduce the pressure loss of the breather pipe 180 to the extent that the internal pressure of the air compressor 100 can be reduced or prevented from becoming excessively high. As shown in FIG. 6, when the pressure loss of the breather pipe 180 does not increase linearly with respect to the increase in the accumulated amount of mist, the first threshold BT is a change in which the rate of increase in pressure loss increases rapidly. It may be set using points.

As shown in FIG. 5, when the calculated mist accumulation amount 646 is equal to or less than the first threshold value BT (S70: NO), the control device 60 proceeds to step S74, and stores the calculated mist accumulation amount 646 in the memory 64. Store and update to complete the process. If the mist accumulation amount 646 is larger than the first threshold value BT (S70: YES), the control device 60 proceeds to step S72 and notifies that the breather pipe 180 is due for maintenance. That the breather pipe 180 is due for maintenance means that the breather pipe 180 or the filter portion 184 needs to be cleaned or replaced. In this embodiment, the control device 60 notifies that the filter portion 184 needs to be replaced as a notification that the breather pipe 180 is due for maintenance. The content of the notification that the breather pipe 180 is due for maintenance is not limited to the notification that the filter portion 184 needs to be replaced. It is also possible to notify only that the pipe 180 is due for maintenance. If the breather pipe 180 does not have the filter portion 184, the notification may be a notification that the pressure loss of the breather pipe 180 is abnormal or a notification that the inside of the breather pipe 180 needs to be cleaned. As a method of notification, for example, display on a display provided in the air compressor 100, the fuel cell system 200 equipped with the air compressor 100, and the fuel cell vehicle equipped with the air compressor 100, or voice from a speaker are used. It may well be transmitted to a remote administrator or the like using data communication or the like via a network. In addition to notifying that there is an abnormality in the filter unit 184, a notification may be made to prompt the stop of the air compressor 100, the fuel cell system 200, and the fuel cell vehicle in which the air compressor 100 is mounted. may be performed. After finishing the notification, the control device 60 ends the process. When step S72 is completed, mist accumulation amount 646 in memory 64 may be reset.

As described above, according to the air compressor 100 of the present embodiment, the control device 60 uses the first value related to the pressure loss of the breather pipe 180 to determine the maintenance timing of the breather pipe 180 . According to this embodiment of the compressor, the time for maintenance of the breather pipe 180 is determined using the mist adhesion speed related to the pressure loss in the breather pipe 180 . Therefore, it is possible to suppress an increase in the pressure loss of the breather pipe 180, and it is possible to reduce or prevent the occurrence of an abnormality such as an oil leak from the motor accommodating portion due to the pressure increase in the air compressor 100.

According to the air compressor 100 of the present embodiment, the control device 60 multiplies the mist adhesion speed pre-associated with each operating point of the air compressor 100 by the operating time of the air compressor 100 to calculate The maintenance timing of the breather pipe 180 is determined using the mist adhesion amount of . Therefore, it is possible to estimate the amount of increase in pressure loss of breather pipe 180 based on the driving conditions of air compressor 100, and to more accurately determine the maintenance timing of breather pipe 180. FIG. In addition, the timing for maintenance of breather pipe 180 can be determined by a simple method without providing a sensor for measuring the pressure loss of breather pipe 180 .

According to the air compressor 100 of the present embodiment, the control device 60 calculates the mist adhesion amount for each operating point for driving the air compressor 100, and the accumulated mist amount, which is the total value obtained by integrating the mist adhesion amount for each operating point. exceeds a predetermined first threshold value BT, it is determined that it is time for maintenance of the breather pipe 180 . By associating the mist deposition speed with each operating point of the air compressor 100, it is possible to calculate the mist accumulation amount corresponding to the driving of the air compressor 100 with the change of the operating point. Therefore, it is possible to determine a more accurate maintenance timing based on the drive history of the air compressor 100 .

According to the air compressor 100 of this embodiment, the breather pipe 180 is provided with the replaceable filter portion 184 . When determining that it is time for maintenance of the breather pipe 180, the control device 60 notifies that the filter portion 184 needs to be replaced. By urging the user or the like of air compressor 100 to replace filter portion 184, an increase in pressure loss in breather pipe 180 can be suppressed more reliably.

According to the air compressor 100 of the present embodiment, the controller 60 stores in the memory 64 the mist amount map 644 that associates the mist adhesion speed with the operating point of the air compressor 100 . By associating the mist deposition speed with the operating point on the existing compressor map 642 , the amount of accumulated mist can be calculated based on the drive control of the air compressor 100 . Therefore, it is possible to improve the processing speed of maintenance timing determination for breather pipe 180 by control device 60 .

B. Other embodiments:
(B1) In this embodiment, each operating point of the compressor map 642 and the mist amount map 644 is determined by the pressure ratio of the air compressor 100 and the discharge flow rate. On the other hand, the operating point can be set, for example, instead of the pressure ratio of the air compressor 100, or together with the pressure ratio of the air compressor 100, to the rotation speed of the motor 130 of the air compressor 100, the power consumption by the air compressor 100, and the fuel cell. A parameter relating to the output of at least one of the air compressor 100 out of the required power for 20 may be used. Also, the mist adhesion speed, mist adhesion amount, and mist accumulation amount can be obtained by multiplying the rotation speed of the motor 130 of the air compressor 100, the power consumption of the air compressor 100, and the required power for the fuel cell 20, for example, by a correction value. , may be calculated for each operating point. According to the air compressor 100 of this form, the mist adhesion speed and the mist adhesion are determined by using the mist adhesion speed, the rotation speed of the motor 130 of the air compressor 100, the power consumption of the air compressor 100, and the required power for the fuel cell 20. It is possible to calculate the amount of mist and the accumulated amount of mist, and determine the maintenance timing of the breather pipe 180 .

(B2) In the above embodiment, an example was shown in which the mist adhesion speed is used as the first value. On the other hand, the first value is not limited to the mist adhesion speed, but includes, for example, the amount of change in pressure loss per unit time in the breather pipe 180, the amount of change in pressure loss per unit time in the filter section 184, the breather Various parameters related to the amount of change in pressure loss per unit time in breather pipe 180 or filter section 184, such as the amount of change in the flow rate of fluid passing through pipe 180 or filter section 184, may be used. In this case, for example, the second value can be the amount of pressure loss that has increased in breather pipe 180 or filter portion 184, or the amount of decrease in flow rate passing through breather pipe 180 or filter portion 184. The latest value of the pressure loss or flow rate of the breather pipe 180 or the filter section 184 can be used for the third value, and the pressure loss or flow rate may be used instead of the amount of accumulated mist as the first threshold value BT. .

(B3) In the above embodiment, an example was shown in which the mist adhesion speed is used as the first value. On the other hand, the first value is not limited to the mist adhesion speed, and includes the pressure inside the filter portion 184 in the breather pipe 180 and the pressure outside the filter portion 184, that is, the outside air pressure in this embodiment. may be used. As the differential pressure of the filter section 184, a value detected by a differential pressure sensor or a difference between a pressure sensor arranged inside the filter section 184 and the atmospheric pressure may be used. In this case, when the differential pressure of the filter portion 184 exceeds, for example, a predetermined second threshold value, it may be determined that it is time for maintenance of the breather pipe 180 . The second threshold value is set using the differential pressure of the filter portion 184 that can increase the internal pressure of the air compressor 100, that is, the differential pressure of the filter portion 184 that can cause a pressure loss to the extent that the internal pressure of the air compressor 100 is not released to the atmosphere. you can According to the air compressor 100 of this embodiment, the differential pressure of the filter portion 184 is detected using the sensor, so that the maintenance timing of the breather pipe 180 can be determined more accurately.

(B4) In the above embodiment, an example was shown in which the mist adhesion speed is used as the first value. On the other hand, the first value is not limited to the mist adhesion speed, and the accumulated driving period of the air compressor 100 may be used. In this case, control device 60 may determine that it is time for maintenance of breather pipe 180 when the accumulated driving period of air compressor 100 exceeds a predetermined period. The predetermined period may be set using, for example, an accumulated drive period during which pressure loss occurs in breather pipe 180, which may cause the internal pressure of air compressor 100 to rise. The predetermined time period may be determined theoretically, experimentally, or by simulation.

(B5) In the above embodiment, the air compressor 100 that is provided in the fuel cell system 200 and pressure-feeds the oxidant gas to the fuel cell 20 was described as an example, but the application of the air compressor 100 is not limited to this, and gas and liquid It may be various compressors for pumping fluid such as.

The present disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from the scope of the present disclosure. For example, the technical features of the embodiments corresponding to the technical features in each form described in the outline of the invention are used to solve some or all of the above problems, or Alternatively, replacements and combinations can be made as appropriate to achieve all. Also, if the technical features are not described as essential in this specification, they can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 20... Fuel cell 30... Oxidizing gas supply/exhaust system 31... Air cleaner 32... Atmospheric pressure sensor 34... Air flow meter 35... Intercooler 36... Inlet valve 37... Outlet valve 38... Discharge side pressure sensor, 39... Bypass valve, 50... Fuel gas supply and discharge system, 51... Fuel gas tank, 52... On-off valve, 53... Regulator, 54... Injector, 55... Circulation pump, 57... Gas-liquid separator, 58... Exhaust/drain valve, 60 CONTROL DEVICE 62 MICROPROCESSOR 64 MEMORY 100 AIR COMPRESSOR 110 OIL RESERVOIR 112 OIL PUMP 120 ROTATING BODY 121 ROTATING BODY 122 ROTATING BODY STORAGE 130 MOTOR , 131... Motor rotating shaft 132... Rotor 133... Coil 134... Stator 140, 144... Bearing case 141... Bearing 150... Motor accommodating part 153, 153a, 153b, 153c, 153d... Oil circulation path, DESCRIPTION OF SYMBOLS 160... Motor part 170... Mechanical seal 172... Fixed ring 174... Rotating ring 180... Breather pipe 182... Mist collecting part 184... Filter part 200... Fuel cell system 231... Cathode supply port 232... Cathode discharge port 251 Anode supply port 252 Anode discharge port 302 Cathode supply pipe 306 Cathode discharge pipe 308 Bypass pipe 309 Exhaust gas discharge port 501 Anode supply pipe 502 Anode circulation pipe , 504... Anode exhaust pipe, 642... Compressor map, 644... Mist amount map, 646... Mist accumulated amount

Claims (8)

a compressor,
a rotating body for compressing and sending out a fluid;
a motor that drives the rotating body;
a motor housing portion for housing the motor;
an open pipe for communicating between the inside of the compressor including the motor accommodating portion and the outside;
a maintenance timing determination unit that determines maintenance timing for the open pipe using a first value related to the pressure loss of the open pipe;
compressor. A compressor according to claim 1, wherein
The first value is an index associated in advance with each operating point of the compressor and is an index related to the amount of change in pressure loss per unit period in the open pipe,
The maintenance timing determination unit uses a second value obtained by multiplying the first value by the driving period of the compressor at the operating point to determine the maintenance timing of the open pipe.
compressor. A compressor according to claim 2,
The maintenance timing determination unit
calculating the second value for each operating point that drives the compressor;
Determining that it is time for maintenance of the open pipe when a third value, which is a total value obtained by integrating the second values calculated for each operating point, exceeds a predetermined first threshold value;
compressor. A compressor according to claim 3,
The open tube is provided with a replaceable filter part,
The maintenance timing determination unit notifies that replacement of the filter unit is necessary when determining that it is time for maintenance of the open tube.
compressor. A compressor according to any one of claims 2 to 4,
The maintenance timing determination unit stores a map that associates the first value with the operating point.
compressor. A compressor according to claim 1, wherein
the first value is a cumulative drive period of the compressor;
The maintenance timing determination unit determines that it is time for maintenance of the open pipe when the accumulated driving period of the compressor exceeds a predetermined period.
compressor. A compressor according to claim 1, wherein
Furthermore, a replaceable filter part provided in the open tube;
a differential pressure sensor that detects the differential pressure of the filter unit as the first value,
The maintenance timing determination unit determines that it is time for maintenance of the open pipe when the differential pressure of the filter unit obtained from the differential pressure sensor exceeds a predetermined second threshold value.
compressor. A compressor control method comprising:
The amount of change in pressure loss per unit period in an open tube for communicating between the inside of the compressor, which includes a motor housing section for housing a motor that drives a rotating body for compressing and sending out fluid, and the outside. calculating a second value by multiplying an associated first value, pre-associated for each operating point of the compressor, by the operating period of the compressor at the operating point;
using the calculated second value to determine when to perform maintenance on the open tube;
Compressor control method.

Images