A vacuum exhaust system includes a plurality of low pressure vacuum pumps that operate in a molecular flow region and evacuate a plurality of vacuum chambers. A plurality of chamber valves are positioned between the low pressure vacuum pumps and the plurality of vacuum chambers. A plurality of branch channels are each connected to a corresponding exhaust of the plurality of low pressure vacuum pumps and a main channel is formed from a confluence of the branch channels. An intermediate vacuum pump is connected to the main channel and operates in a viscous flow region. A higher pressure vacuum pump operates in a higher pressure viscous flow region and is connected to an exhaust of the intermediate pressure vacuum pump. A plurality of bypass channels, each having a valve, provide a fluid communication path between at least some of the plurality of vacuum chambers and a higher pressure vacuum pump.

A vacuum exhaust system includes a plurality of low pressure vacuum pumps that operate in a molecular flow region and evacuate a plurality of vacuum chambers. A plurality of chamber valves are positioned between the low pressure vacuum pumps and the plurality of vacuum chambers. A plurality of branch channels are each connected to a corresponding exhaust of the plurality of low pressure vacuum pumps and a main channel is formed from a confluence of the branch channels. An intermediate vacuum pump is connected to the main channel and operates in a viscous flow region. A higher pressure vacuum pump operates in a higher pressure viscous flow region and is connected to an exhaust of the intermediate pressure vacuum pump. A plurality of bypass channels, each having a valve, provide a fluid communication path between at least some of the plurality of vacuum chambers and a higher pressure vacuum pump.

An object of the present invention is to realize inexpensive and simple compressor number control of gas compressors. In order to achieve the above object, there is provided a gas compressor set as a master gas compressor that performs compressor number control on N slave gas compressors, the compressor including: a communication I/F that is communicable with the slave gas compressors; and a control unit. When one cycle of communication with the N slave gas compressors in N communication sets is defined as a total compressor number communication cycle, in an initial total compressor number communication cycle, in first to N.sup.th communication sets, the control unit transmits a first response request to each of first to N.sup.th slave gas compressors, and when the control unit receives a response from the slave gas compressors, the control unit determines that communication connection with the slave gas compressors has succeeded, and when the control unit receives no response from the slave gas compressors, the control unit determines that communication connection with the slave gas compressors has failed. In second and following total compressor number communication cycles, the control unit transmits a second response request to the slave gas compressors, with which the communication connection has succeeded, in each of the communication sets, and transmits the first response request to the slave gas compressors, with which the communication connection has failed, at different timings.

An object of the present invention is to realize inexpensive and simple compressor number control of gas compressors. In order to achieve the above object, there is provided a gas compressor set as a master gas compressor that performs compressor number control on N slave gas compressors, the compressor including: a communication I/F that is communicable with the slave gas compressors; and a control unit. When one cycle of communication with the N slave gas compressors in N communication sets is defined as a total compressor number communication cycle, in an initial total compressor number communication cycle, in first to N.sup.th communication sets, the control unit transmits a first response request to each of first to N.sup.th slave gas compressors, and when the control unit receives a response from the slave gas compressors, the control unit determines that communication connection with the slave gas compressors has succeeded, and when the control unit receives no response from the slave gas compressors, the control unit determines that communication connection with the slave gas compressors has failed. In second and following total compressor number communication cycles, the control unit transmits a second response request to the slave gas compressors, with which the communication connection has succeeded, in each of the communication sets, and transmits the first response request to the slave gas compressors, with which the communication connection has failed, at different timings.

A high pressure gas lift compressor system and method of using the system for supplying compressed gas to multiple wells are provided. The system includes a compressor having multiple compressor cylinders. Each cylinder has its own gas inlet line and dedicated gas outlet line that supplies compressed gas from that cylinder directly to a wellbore to provide artificial gas lift. Each cylinder also has its own control valve upstream of the cylinder to control the suction pressure to the cylinder. A desired gas flow rate to each well may be input, and the control valve is adjusted accordingly to achieve the flow rate. By inputting a flow rate for each separate cylinder, the flow rate to each well may be independently controlled.

A high pressure gas lift compressor system and method of using the system for supplying compressed gas to multiple wells are provided. The system includes a compressor having multiple compressor cylinders. Each cylinder has its own gas inlet line and dedicated gas outlet line that supplies compressed gas from that cylinder directly to a wellbore to provide artificial gas lift. Each cylinder also has its own control valve upstream of the cylinder to control the suction pressure to the cylinder. A desired gas flow rate to each well may be input, and the control valve is adjusted accordingly to achieve the flow rate. By inputting a flow rate for each separate cylinder, the flow rate to each well may be independently controlled.

It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.

It is disclosed a method for reducing the pulsation level in a multi-compressor plant where each compressor of a plurality of compressors is driven by a respective motor. The method manages to reduce the pulsation level by starting a first motor of a first compressor and then starting in succession each one of the other motors in a way to synchronize all motors between each other with a specified phase shift.

A method for controlling and/or monitoring a compressor system is provided. The compressor system includes one or more compressors and one or more peripheral devices. The compressors and peripheral devices are arranged or connected in a predetermined configuration. The compressor system is controlled and/or monitored by a control/monitoring unit. The method involves creating one or more derived models on the basis of one or more initial models of the compressor system that are based on a P&I diagram. The derived models take into account the operative interrelationships among the individual compressors and peripheral devices, and optionally also dynamic processes. The one or more derived models form the basis for subsequent control, monitoring, diagnosis or evaluation routines.

A method for controlling and/or monitoring a compressor system is provided. The compressor system includes one or more compressors and one or more peripheral devices. The compressors and peripheral devices are arranged or connected in a predetermined configuration. The compressor system is controlled and/or monitored by a control/monitoring unit. The method involves creating one or more derived models on the basis of one or more initial models of the compressor system that are based on a P&I diagram. The derived models take into account the operative interrelationships among the individual compressors and peripheral devices, and optionally also dynamic processes. The one or more derived models form the basis for subsequent control, monitoring, diagnosis or evaluation routines.