Abstract: An energy saving three pump waste water pump station design that eliminates the high energy usage of traditional waste water pump stations, reduces maintenance costs to the pumps and increases the useful lives of the pumps by having a primary pump running continuously, a second pump mining during high demand periods and a third pump functioning primarily as a back up pump. Unlike conventional pump-station designs, the Energy Saving Green Pump Station Design utilizes a single float switch panel. Whereas independent float switches trigger start-stops in conventional pump station designs, the Green design incorporates a remote controllable panel for rotating the primary, secondary and third pumps on a schedule. This design also provides a process for determining in-flow rates for a pump station and efficiency operating points of pumps so that the most efficient pumps with the lowest horsepower can be selected.

Abstract: A control device of a piston pump unit comprising at least two piston-cylinder units that operate in a phase-shifted manner for the purpose of liquid chromatography and to a piston pump unit is described. The control device corrects fluctuations of the system pressure while switching from one piston cylinder unit to the respective other piston cylinder unit. The fluctuations can occur as a result of the cooling of the liquid medium that is heated in an adiabatic manner during a pre-compression phase in the working piston. The control unit controls the piston speed of at least one piston-cylinder unit during the transition phase depending on at least one characteristic, which is ascertained from chronologically previously detected pressure values, such that variations of the system pressure as a result of the cooling of the adiabatically heated medium are at least partially compensated for.

Abstract: To provide a hybrid type or battery type working machine which hardly gives a feeling of strangeness on an operation to an operator and in which electric power stored in a storage battery can be used effectively within an operation scheduled time set in advance. An amount of reduction in the amount of electricity stored in an electric storage device 60 in a predetermined time t1 after an working machine starts up is obtained, and an operation possible time t2 is obtained from the obtained amount of reduction and a residual amount of the electricity stored in the electric storage device 60. Further, determination is made as to whether the obtained operation possible time t2 reaches a remaining time of an operation scheduled time obtained by subtracting a currently spent real operation time from the operation schedule time set in advance.

Abstract: A pump system containing no external parts or valves is provided. The pump system is characterized by a common type of actuating mechanism and incorporates reversibly expanding actuators, preferably electroactive actuators. Fluid is caused to move at a selected flow rate and direction by sequentially activating contiguous actuators located inside the pump. The pump may be used to pump a variety of fluids and may be used in various industrial, commercial, medical, aeronautical, or military applications.

Abstract: A snowmobile having an electronic oil pump fluidly connected to an oil tank thereof is disclosed. The electronic oil pump is fluidly connected to an engine of the snowmobile for delivering lubricant to the engine. An electronic control unit is electrically connected to the electronic oil pump for controlling actuation of the electronic oil pump. A method of operating an electronic oil pump is also disclosed.

Abstract: A set of piston compressors (2, 4, 6, 8) for use in a refrigeration system comprises a fluid connection (10) between the crank cases of the piston compressors (2, 4, 6, 8) for allowing oil compensation between said piston compressors (2, 4, 6, 8); and a control unit (12) which in operation monitors the running time of each piston compressor (2, 4, 6, 8) and, in case all piston compressors (2, 4, 6, 8) are running, subsequently interrupts the operation of a respective piston compressor (2, 4, 6, 8) for a predetermined period of time for oil compensation if its running time reaches a predetermined maximum running time.

Abstract: A method of controlling an electric compressor of the present invention, comprises the steps of: setting a specified constant rotating speed as a target rotating speed (Rt) of a DC motor (103) (S1); obtaining an actual measurement rotating speed (Rm) which is a measurement value of a rotating speed of the DC motor (103) (S2); adjusting a duty ratio of driving electric power of the DC motor (103) so that the actual measurement rotating speed (Rm) matches the target rotating speed (Rt) (S3); and newly setting the target rotating speed based on a change in the duty ratio (S4).

Abstract: A system and method are provided for reducing the energy consumed by a pump jack electric motor by reducing the supply voltage to the motor when the motor would be generating energy in open loop mode. By substantially eliminating the energy generation mode, the braking action of the utility grid in limiting the acceleration of the motor and system that would otherwise occur is substantially removed. The motor and system will speed up, allowing the natural kinetic energy of the cyclic motion to perform part of the pumping action.

Abstract: A system and method are disclosed for turning off the voltage to a pump jack electric motor during predetermined periods of time to save energy. In the method, the motor's response to closed-loop control may be evaluated over several pump strokes. The periods of the pump stroke when it is feasible to turn off the motor may be identified. The consistency of the measurements over several strokes may be evaluated. The motor may be turned off during predetermined periods on subsequent pump strokes when each pump stroke shows sufficiently similar behavior to that predicted during the closed-loop control process. The system may return to the closed-loop control process after a predetermined period of time to adjust to any changes in the system.

Abstract: In an electric water pump for circulating cooling water of an engine mounted on a vehicle or similar, a time interval to switch energized phase of a pump motor is set to longer than a time interval during a normal flow rate control (during a flow rate control at a flow rate equal to or more than a flow rate where an electromotive force generated at a non-energized phase is detectable). In the case where a pump discharge pressure (or a water temperature of the cooling water) repeatedly increases and decreases in this extremely low flow rate state, it is determined that the electric water pump normally rotates as required. This allows providing the extremely low flow rate state between a water stop state and a water circulation state in a control for stop of water in an engine cooling system.

Abstract: Embodiments of the invention provide a pumping system for at least one aquatic application. The pumping system includes a pump, a motor coupled to the pump, and a controller in communication with the motor. The controller determines an actual power consumption of the motor and compares the actual power consumption to a reference power consumption. The controller also determines that the pump is in an unprimed condition if the actual power consumption is less than the reference power consumption and that the pump is in a primed condition if the actual power consumption is at least equal to the reference power consumption.

Abstract: A swimming pool or spa pump control system to selectively control the operation of a recirculating pump to prevent damage to the recirculating pump that could result from specific operating conditions and to optimize energy consumption by varying the run time of the recirculating pump throughout the year as a function of the sun's energy impacting the earth's surface as a measure of solar radiation incident on the surface of the pool water or solar heat energy incident on the pool water comprising a controller including a microcontroller to calculate the pump run time for a geographically specific location dependent upon the time of year or date based upon the solar radiation or heat energy adjusted for specific swimming pool or spa site, and a plurality of sensors to monitor various operating conditions coupled to the controller to deactivate the recirculating pump when any one of the operating conditions exceeds a predetermined or set value.

Abstract: When blowing out air, an air blower provides a user with feeling of being exposed to natural wind. A control unit of an air conditioner controls a fan motor of the air conditioner so that an airflow speed of a fan of the air conditioner changes over time with a synthesis pattern composed of a plurality of patterns including a sine-wave-like waveform pattern and a hill-like variation pattern having a width of less than a quarter cycle of the waveform pattern and a height of equal to or greater than an amplitude of the waveform pattern for each cycle of the waveform pattern.

Abstract: A compressor apparatus includes a power source (26), a shell (12; 42), an electric motor (28; 52; 100; 200) having motor windings, and a control assembly (106; 206). The electric motor (28; 52; 100; 200) is located within the shell (12; 42). The control assembly a control assembly (106; 206) provides power to the motor windings from the power source (26) in two modes. A first mode provides power to the motor windings to generate heat without producing force output with the motor (28; 52; 100; 200). A second mode provides power to the motor windings to produce force output with the motor (28; 52; 100; 200). The control assembly (106; 206) activates the first mode for a selected time period prior to activation of the second mode in order to drive out a fluid (36) to reduce a risk of a flooded compressor start.

Abstract: A pump has a signal processor, including one forming part of a printed circuit board assembly, that receives signaling containing information about a voltage supplied to a motor to run a particular pump model, and also containing information about whether a current draw of the pump is lower than a predetermined low current level or is higher than a predetermined high current level; and determines whether to shut off the pump after a predetermined time, based on the signaling received. The signal processor provides control signalling to shut off the pump after the predetermined time if the current draw of the pump is lower than the predetermined low current level or is higher than the predetermined high current level, where the predetermined low current level and the predetermined high current level depend on the voltage being supplied to the motor to run the particular pump model.

Abstract: A control arrangement for controlling a piston pump unit for liquid chromatography, in particular high-performance liquid chromatography, is described. The piston pump unit has at least two piston-cylinder units which operate cyclically in a phase-offset manner and generate, at an outlet port, a predetermined flow of a liquid medium to be delivered. A system pressure is established at the outlet port, irrespective of an associated fluid load resistance. The control arrangement is configured to record the pressure in the cylinder volume of at least a first of the at least two piston-cylinder units. During a measurement phase of the compression phase of the first piston-cylinder unit or during a measurement phase of the decompression phase of the first piston-cylinder unit, the control arrangement stops the drive device for the first piston-cylinder unit for a predetermined time period and in the process records measurement data which characterize the time profile of the pressure.

Abstract: Methods, systems, and techniques for structuring, operating, and/or controlling a variable fluid flow system of a machine are provided. In various embodiments, a supplemental pump and/or an electric motor can be leveraged in combination with the existing components of a machine, such as the main fluid pump of the machine.

Abstract: Method for controlling a refilling motor (2) that drives a hydraulic pump (4) that refills at least one pressure accumulator (8), this accumulator thereafter delivering the hydraulic pressure (P) to a hydraulic traction machine (20) of a hybrid vehicle, characterized in that it takes account both of the rate of discharge of the pressure accumulator (8) and of the time to start (?i) the refilling motor (2) so as to manage this start in such a way that this accumulator more or less reaches its minimum operating pressure level (PI) at the end of this start (t1).

Abstract: Embodiments of the invention provide a pumping system for at least one aquatic application. The pumping system includes a pump, a motor coupled to the pump, and a controller in communication with the motor. The controller determines an actual power consumption of the motor and compares the actual power consumption to a reference power consumption. The controller also determines that the pump is in an unprimed condition if the actual power consumption is less than the reference power consumption and that the pump is in a primed condition if the actual power consumption is at least equal to the reference power consumption.

Abstract: A pool recirculation pump safety system includes a power supply assembly operable to selectively supply operating power to a recirculation pump motor, an entrapment detection assembly operable to detect a change in a recirculation system parameter indicative of swimmer entrapment at a suction intake opening, and a timer assembly operable to automatically bypass the entrapment detection assembly for a predetermined time period upon energization of the system. During operation of the recirculation pump motor, the system is configured to secure operating power to the recirculation pump motor upon detection of the indicative recirculation system parameter change after the predetermined time period. The entrapment detection assembly and the timer assembly can be arranged to form a switchable neutral connection for a power relay of the power supply assembly.

Abstract: A water delivery system is provided, comprising at least one faucet device with a cold water faucet part and a hot water faucet part, a cold water line to the at least one faucet device, a tankless heater device for heating water, a hot water line having a first portion running from an outlet of the tankless heater device to the at least one faucet device and having a second portion running from the at least one faucet device to an inlet of the tankless heater device, and a circulatory pump arranged in the second portion of the hot water line, wherein the circulatory pump has a prefixed first performance level and a prefixed second performance level, wherein the first performance level causes a finite water flow in the hot water line which is below an operation threshold value of the tankless heater device.

Abstract: A pump system including a pump and a sensor system for monitoring a fluid production of the pump and providing an output indicative of the fluid production. The sensor system is configured to use at least two discreet methodologies for measuring the fluid production. The pump system further includes a control system operatively coupled to the sensor system and the pump and configured to automatically vary the speed of the pump at least partially based upon the output of the sensor system.

Abstract: A water-lifting pump apparatus which is free of a discharge valve and a check valve, is low in cost, and is capable of reducing vibration and noise due to a waterfall after the end of water pumping operation. The water-lifting pump apparatus has a suction tank (10), a discharge tank (20), a pump (30) for pumping water in the suction tank (10) into the discharge tank (20), and a discharge piping (50) connected to a discharge side of the pump, an actuator (60) for actuating the pump (50), a reverse flow preventing mechanism (80) for preventing a reverse flow of water pumped into the discharge tank (20) toward the discharge piping (50), and a back flow rate control (90) for controlling the flow rate of a waterfall falling from the discharge piping (50) into the suction tank (10) when pumping operation is finished.

Abstract: An energy management system for a home network is provided. The energy management system includes one or more power consuming devices, including at least a pool pump system having a motor and a filter with a filtration cycle, a central controller operatively connected to the power consuming devices and configured to receive and process a signal indicative of the current state of an associated utility, including at least a peak demand state and an off-peak demand state, and a display. The central controller is configured to operate the pool pump system in one of a plurality of operating modes, including at least a normal operating mode and an energy savings mode, and to provide pool pump usage information to a user via a user interface on the display.

Abstract: A compressor includes at least one current sensor and processing circuitry in communication with the at least one current sensor. The processing circuitry declares a locked rotor condition when current drawn by the compressor is at least forty percent of peak locked rotor current.

Abstract: Embodiments of the invention provide a pumping system for at least one aquatic application. The pumping system includes a pump, a motor coupled to the pump, and a controller in communication with the motor. The controller determines an actual power consumption of the motor and compares the actual power consumption to a reference power consumption. The controller also determines that the pump is in an unprimed condition if the actual power consumption is less than the reference power consumption and that the pump is in a primed condition if the actual power consumption is at least equal to the reference power consumption.

Abstract: A water-injected compressor, which injects the water inside the separator 3 into the compressor and discharges the water along with compressed air into the separator and then gains condensed and separated water, has the compressor stopping and then, if staying at a stop for a predetermined duration of time without activating, becoming activated and operating for a set duration of time.

Abstract: Systems and methods for providing an improved strategy for controlling a variable speed water pump in a vehicle. In some embodiments, more than one water pump speed function is calculated based on values obtained from vehicle sensors, and a controller chooses among the water pump speed function results to set a water pump speed. In some embodiments, the water pump speed is increased when driveline torque is greater than a threshold amount for an amount of time that varies based on the driveline torque. In some embodiments, ambient temperature is considered while determining whether the water pump should provide full coolant flow to an auxiliary coolant loop of a trailer.

Abstract: Control process for a piezoelectric pump (100) of an electric household appliance comprising a pump chamber (110) equipped with a mobile wall (111) displaceable under the action of a piezoelectric actuator (111A), characterized in that during a startup phase of the pump (100), the piezoelectric actuator (111A) is supplied during a plurality of alternations with an alternating supply signal having a voltage U bringing about a substantial deformation of the piezoelectric actuator (111A) for a maximum sweeping of the volume of the pump chamber (110) by the mobile wall (111), and further characterized in that the pump startup phase is followed by a normal operation phase during which the supply signal is modified so that the mean flow rate provided by the pump (100) is less than the flow rate provided during the startup phase.

Abstract: A powder feed apparatus for a powder spraycoating equipment includes a dense phase powder pump fitted with at least two feed chambers, alternatingly discharging coating powder. Each feed chamber includes a powder intake valve to aspirate coating powder during a suction stage and one powder outlet valve to discharge coating powder during a discharge stage. Each feed chamber further includes control valves to operate the dense phase powder pump and a control unit controlling the dense phase powder pump by the control valves. A dependence mode of the total open time (ttotal) of the powder intake valves defines the dependence of the total open time (ttotal) on an adjustable nominal value (mp) adjusted by a powder adjusting element and relating to the rate of powder to be conveyed by the dense phase powder pump, and defining a response delay time (tdelay) and an apparatus constant (C).

Abstract: An air compressor 20, for enabling to restart a fan motor when an inverter trip generates within an inverter control of the fan motor, as well as, to continue supplying of compressed air therefrom, comprises: a compressor main body 1; a compressor motor 2 for driving this compressor main body 1; a fan motor 9b for driving a fan 9a; an inverter for controlling the fan motor; and a controller 10 for controlling driving of the compressor motor 2 and driving of the fan motor 9b. The controller 10 conducts such control that the fan motor 9b is brought into a restart waiting condition while continuing operation of the compressor motor 2 when an inverter trip generates, and thereafter to restart the fan motor 9b.

Abstract: A control device for controlling a shower waste pump, includes a housing, a pump setting, and an over-run setting. The pump setting, by way of a control element, preferably a manually adjustable potentiometer, allows selective setting of a maximum pumping capacity of the waste pump. The over-run setting, also by way of a control element, allows selective setting of an over-run period from a predetermined range during which the waste pump continues to operate after fluid flow through the waste pump has ceased or substantially ceased. The over-run setting and the pump setting together optimize operation of the waste pump, so that the over-run period of the waste pump can be set based on the selected maximum pumping capacity.

Abstract: A dry pump apparatus comprises; a pumping mechanism, a controller for controlling the operation of the pumping mechanism, and a sensor for sensing the operating temperature of the pumping mechanism. The controller is configured to carry out an automated shutdown sequence involving the following steps; a) ceasing operation of the pumping mechanism b) monitoring the temperature of the pumping mechanism by means of the temperature sensor c) at least one pre-selected temperature interval, initiating operation of the pumping mechanism for a fixed time period so as to purge a proportion of contaminant particulate matter present until a predefined temperature is reached or a predefined time limit has passed. By carrying out these steps the incidence of powder compaction between component parts of the apparatus which may contract during shutdown, and consequential restart failure and down time, can be significantly reduced.

Abstract: Known water supply systems are fed from a source of water such as a tank (6) via a pump (5) to outlets which are occludable by means of a cock (C1-C3). A water pressure sensitive electrical switch (S1) is located downstream of the pump (5) and upstream of the outlets. The switch (S1) is connected in series with an electrical supply for the pump and turns the pump on in response in a drop in water pressure downstream of the switch. Similarly the pump is turned off in response to water pressure downstream to the switch reaching a predetermined minimum pressure, A control system is disclosed in the form of a timer (T) connected in parallel with the pump (5) and energized via the switch (S1). A normally closed safeguard switch (S2) is connected in series with the pump and rendered non-conductive by the timer (T) being energized for a predetermined period.

Abstract: A pump assembly includes a centrifugal pump driven by an electric motor and is provided with a time display which is formed by an annular row of light diodes, wherein a time is assigned to each light diode.

Abstract: An electrical control system for energy efficient pump stations providing for continuous operation of a single primary pump with a second pump functioning as the support pump and a third pump acting as the standby/emergency pump. All pumps are of equal horsepower and horsepower selection is determined by the system curve to select the lowest, most efficient horsepower necessary to discharge water at the highest inflow rate while not allowing the water level to drop below the submerged pump level during continuous running of the primary pump. A timer having an indicator arm rotates one full revolution every thirty days changing the pump sequence to reduce wear and tear on individual pumps. Each pump functions as the primary, secondary and backup/emergency pump for the same number of hours during the monthly cycle. Adding control circuits enables one or more pumps to be added when necessary.

Abstract: A method of controlling a motor operating a pumping apparatus of a system includes determining a trip value for a parameter, floating the trip value, and monitoring the operation of the pump. Monitoring the operation of the pump includes determining a value for the parameter, comparing the value to the trip value, and determining whether the comparison indicates a condition of the pump. The method of controlling the motor also includes controlling the motor to operate the pump based on the condition of the pump.

Abstract: An anti-noise method for the Direct Current Brushless motor System, which includes a startup circuit, phase detective circuit, motor phase commutation circuit, driving circuit, BEMF detective circuit, and frequency detector, utilizes the BEMF detective circuit to detect the BEMF induced from the coils of the outer motor, and utilizes the sampled voltage phase to determine rotation speed and phase of the external motor by the phase detection circuit and frequency detector. Further, the sampling voltage of the BEMF detection circuit is feedback controlled by the frequency detector, utilized to keep good BEMF to noise ratio, and avoids the BEMF sampling error from the system.

Abstract: It is described a method for controlling an oxygen pump cell of a sensor in an internal combustion engine or in the exhaust gas after treatment system of such an engine, comprising the step of adding, to a feedback control of the current in the pump cell, a further feed-forward control path estimating an expected oxygen pump current on the basis of characteristics of the exhaust gas composition calculated from engine operation data.

Abstract: An HV-ECU performs a step of detecting an atmospheric pressure, a step of calculating a maximum value of a boost voltage corresponding to the atmospheric pressure by using a map, and a step of setting the maximum value as a system voltage value and controlling a DC/DC converter. Moreover, the HV-ECU may calculate a resistance value of a gate resistance of a switching element corresponding to the atmospheric pressure by using the map and control the gate resistance to achieve the set resistance value.

Abstract: In a method of operating a compressor at startup, the compressor is rotated in reverse for a brief period of time. The compressor is of a type that does not compress liquid when rotated in reverse. The purpose is to boil off the liquid refrigerant from the oil by heating and agitating the mixture of oil and refrigerant in the oil sump. This results in a much more benign forward start as less refrigerant is drawn into the compressor pump and the amount of oil pumped out of the compressor on start up is minimized. Also, the viscosity of oil is increased and lubrication of the bearings is improved. After a short period of time reverse rotation is stopped and the compressor can start rotating in the forward direction. The short period of time of reverse rotation is varied based upon system conditions. In one embodiment, the variation can occur by reducing the reverse run time as ambient temperature increases.

Abstract: A controller for a system having at least one variable-capacity, pulse-width modulated compressor and at least one fixed-capacity compressor is provided. The controller may include processing circuitry that modulates the at least one variable-capacity, pulse-width modulated compressor to any capacity substantially between ten percent capacity and one hundred percent capacity. The processing circuitry may determine a desired capacity of the at least one variable capacity, pulse-width modulated compressor based on a load sensor signal and a current run percentage of the at least one variable capacity, pulse-width modulated compressor and may toggle the at least one fixed-capacity compressor between a run mode and a shutdown mode based on the desired capacity of the at least one variable-capacity, pulse-width modulated compressor.

Abstract: The invention relates to improvements in compressors and, in particular, to an improvement in a method of controlling variable speed dynamic compressors to avoid ‘motor overload as a result of choking.1 The invention therefore comprises a method of controlling a compressor to provide compressed gas at a target delivery pressure (Pt) and prevent excessive motor power consumption, the compressor being driven by a variable speed motor which has motor windings, wherein the gas inlet temperature (Tin), gas output delivery pressure (Pd), motor speed (Vm) and the motor winding temperature (Tmw) are continuously measured during operation of the compressor. The gas inlet temperature (Tin) is used to determine a predetermined maximum motor winding temperature (Tmwmax) limit. The maximum motor winding temperature (Tmwmax) is used (to set a maximum motor speed (Vmmax) limit.

Abstract: A swimming pool or spa pump control system to selectively control the operation of a recirculating pump to prevent damage to the recirculating pump that could result from specific operating conditions and to optimize energy consumption by varying the run time of the recirculating pump throughout the year as a function of the sun's energy impacting the earth's surface as a measure of solar radiation incident on the surface of the pool water or solar heat energy incident on the pool water comprising a controller including a microcontroller to calculate the pump run time for a geographically specific location dependent upon the time of year or date based upon the solar radiation or heat energy adjusted for specific swimming pool or spa site, and a plurality of sensors to monitor various operating conditions coupled to the controller to deactivate the recirculating pump when any one of the operating conditions exceeds a predetermined or set value.

Abstract: The present invention provides a control method and a control apparatus of an inverter compressor in which when a trip occurs immediately after the inverter is started, retry can be performed in a short period of time with restart being performed in accordance with the detected conditions after the retry waiting times which are different from each other elapse. There are provided two or more kinds of retry waiting times, and the retry waiting time immediately after starting is made shorter than the others.

Abstract: A free piston gas compressor has a cylinder, a piston, the piston reciprocable within the cylinder in alternating compression and expansion strokes. A reciprocating linear electric motor is drivably coupled to the piston. A controller is programmed to control or adjust power input to the linear motor on the basis of a relationship including at least one of the present compression stroke or expansion stroke durations, the relationship being indicative of the top dead center (TDC) position of the piston, including in the absence of any collision. In the preferred embodiment the controller obtains a measure reflecting the difference between the compression stroke duration and the expansion stroke duration and adjusts the power input in response to the obtained measure.

Abstract: An exemplary hydraulic system includes a first digital valve fluidly connectable to a first hydraulic load and a pump. The first valve is operable to fluidly connect the first hydraulic load to the pump. A second digital valve is fluidly connectable to a second hydraulic load and the pump. The second valve is operable to fluidly connect the second hydraulic load to the pump. The system includes a first sensor for detecting a pump discharge pressure and a second sensor for detecting an inlet pressure of the first hydraulic load. A controller is configured to determine a time delay based on the pump discharge pressure and the first hydraulic load inlet pressure and to send a control signal instructing the second valve to commence opening at a time substantially equal to the time delay after commencing closing the first valve.

Abstract: A control for a linear compressor energises the linear motor in harmony with the present natural frequency of the compressor. The controller monitors the present operating frequency and compares the frequency with one or more outer limit thresholds. The control may remove power from the linear motor if the running frequency drops below a lower threshold. The control may reduce power to the linear motor if the running frequency rises above an upper threshold. The control uses compressor running frequency to operate the comperssor within safe operating limits.

Abstract: Driving controlling apparatus and method for a reciprocating compressor capable of stably driving a reciprocating compressor when a reciprocating compressor is operated or an output capacity of the reciprocating compressor is varied, by matching an impedance of the apparatus to an inductance of a motor, and capable of enhancing an efficiency of the reciprocating compressor. The apparatus comprises an output capacity determining unit for determining an output capacity of a reciprocating compressor; an over-stroke preventing unit for preventing an over-stroke of a motor inside the reciprocating compressor; and an impedance matching unit for matching an inductance of the reciprocating compressor to an impedance of the apparatus.

Abstract: To provide an operation control device for a vacuum pump and a method for stopping the operation of the vacuum pump that make it possible to effectively remove products, resulting from solidification and liquefaction of gas in a casing and possibly hindering the rotation of a pump rotor, so that the vacuum pump may be started normally. An operation control device 10 for a vacuum pump having a pump rotor 1 disposed in a casing 2 for free rotation includes a pump rotor control section 15 for controlling the rotation of the pump rotor 1. The pump rotor control section 15 has a function to, after a pump stop action has been taken, rotate the pump rotor 1 in forward and/or reverse directions according to a predetermined timing pattern and then stop the pump rotor 1.