電壓模型使用的電動(dòng)機(jī)參數(shù)較少,在速度高于5%~10%(高速)時(shí).計(jì)算精度較高;低于5%~10%(低速)時(shí),由于電壓太小,計(jì)算誤差大。電流模型使用電動(dòng)機(jī)參數(shù)多,特別是受轉(zhuǎn)子電阻變化的影響大,計(jì)算誤差略大,但這誤差與轉(zhuǎn)速無關(guān)。在有速度傳感器的系統(tǒng)中,高速時(shí)使用電壓模型,控制精度高;低速時(shí)使用電流模型,精度雖不如高速時(shí),但仍能正常運(yùn)行。在無速度傳感器系統(tǒng)中,高速時(shí)∞,靠比較電壓、電流模型的計(jì)算結(jié)果辨識(shí)得到,因此只能達(dá)到有速度傳感器系統(tǒng)低速時(shí)的水平;低速時(shí)由于電壓模型不準(zhǔn),基準(zhǔn)沒了,無法辨識(shí)09,系統(tǒng)只能拋棄矢量控制,改為開環(huán)工作。現(xiàn)在市場(chǎng)上的無速度傳感器矢量控制系統(tǒng)在低速時(shí)都采用開環(huán)控制,性能差,它們只適用于無長(zhǎng)期低速運(yùn)行工況或高速時(shí)調(diào)速精度要求不高的場(chǎng)合。
廈門岳航計(jì)算機(jī)工程有限公司
聯(lián)系人:李素云
企業(yè)QQ:2851195446,2851195466
手機(jī):18965423501
座機(jī):0592-5165501
有的公司宣稱其無速度傳感器矢量控制系統(tǒng)在靜止時(shí)也能產(chǎn)生滿轉(zhuǎn)矩,這固然沒錯(cuò).但有其宣傳成分。因?yàn)樵陟o止時(shí),速度09=0是已知的,不需辨識(shí),一旦運(yùn)轉(zhuǎn)起來,長(zhǎng)期低速運(yùn)行就不行了。表2所示為6SE70系列變頻器在有/無編碼器的性能。
TEAC 193077C2-91 3.5" Floppy Drive 1.44MB
Allen-Bradley 1794-0A16 Flex I/O Output Module w/ 1794-TB3 Terminal Base Ser. A
Allen-Bradley 1794-IE8 Flex I/O Analog Input Module w/ 1794-TB3 Terminal Base
Allen-Bradley 1746-N04I SLC 500 Analog Output Module Series A
Allen-Bradley 1746-NI4 SLC 500 Analog Input Module Ser. A (New)
Allen-Bradley 1746-0A16 SLC 500 Output Module Ser. C (Without Terminal Block)
Allen-Bradley 1746-NT4 Thermocouple Series B
Allen-Bradley 1746-NO4I Analog Output Module Series A
Allen-Bradley 1746-OX8 Output Module Series A
Allen-Bradley 1794-0A16 Flex I/O Output Module w/ 1794-TBN Terminal Base
Allen-Bradley 1794-1A16 Input Module with 1794-TBN Terminal Base
B & R Industrail 2EX301.5 Expansion Slave Module
Micronor MG2G Motor Cam Switch/ Micronor M-35134 Cam/ Bourns 35405-1-102
Micronor MG2G Motor Cam Switch/ Micronor M-35134/ Bourns 35405-1-103
Micronor MG2G Motor Cam Switch Module/Micronor M-35134/Bourns 35405-1-103
Westinghouse NL-1015
Westinghouse NL-1032
Westinghouse NL-1062
Westinghouse NL-515
Westinghouse NL-530
Westinghouse NL-542
Westinghouse NL-552
Westinghouse NL-580
Westinghouse NL-710
Westinghouse NL-731
Westinghouse NL-739
Westinghouse NL-742
Westinghouse NL-743
Westinghouse NL-751A
Westinghouse NL-753
Westinghouse NL513
Westinghouse NL536
Westinghouse NLCI-792
Westinghouse NLEE-2502
Westinghouse NLEP-195
Westinghouse NLHR-2732
Westinghouse NLLA-185
Westinghouse NLM-700B-08
Westinghouse NLOP-593C
Westinghouse NLPA-701
Allen-Bradley 1746-LA16 Output Module SLC500 Ser D 85-265V 50/60Hz
Allen-Bradley 1746-LA16 Input Module SLC500 Ser C 85-132V 50/60Hz
Allen-Bradley 1746-0A16 Output Module SLC500 Ser C 85-265V 50/60Hz
Siemens 6ES5 095/8MC01 Simatic S5 24VDC
Berkeley Process Control, INC. Micro I/O System 5-Slot Rack