JP2004263914A - Heating system and cogeneration system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a heating system for stably supplying heat to heat loads different in heat absorption, and a cogeneration system using the heating system. <P>SOLUTION: This heating system performs hot water supply or space heating or simultaneously performs both of these by connecting a hot water supply circuit 29 and a heating circuit 35 directly or via a heat exchanger 42 to a heat source circulating circuit 32 for circulating hot water heated by a heat source part 6. In an independent space heating operation, a combustor is burnt in a combustion pattern according to the required heat energy of a space heating terminal, and in the other operation except for the independent space heating operation, the combustor is burnt in a combustion pattern according to the required heat energy of a hot water supply terminal. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【００４５】
従って、燃焼制御部１０３は、ステップ２１３において、リモートコントローラで設定された給湯設定温度と給水温度センサ９３の検知温度とを参照して、式１に基づいて２０号相当流量Ｑを演算し、給湯流路３３の湯水の流動量が演算結果の２０号相当流量Ｑとなるように給湯水比例弁８２を制御する。
【００４６】
続いて、燃焼制御部１０３は、給湯必要流量Ｑｓを算出する（図３ステップ２１４参照）。ここに、給湯必要流量Ｑｓとは、前記式１で示される２０号相当流量の湯水を給湯栓７から給湯するために、燃焼機６から分岐給湯流路８３を介して供給を要する湯水の流量であり、式２で与えられる。
【００４７】
【数２】

【００４８】
式２は、次のようにして導出される。図１に示すように、分岐給湯流路８３を介して燃焼機６から混合弁８０へ供給を要する湯水の流量は給湯必要流量Ｑｓであり、その温度をＴｓとする。また、給水流路８５を介した混合弁８０への給水流量および給水温度を各々Ｑｗ，Ｔｗとする。また、混合弁８０から給湯流路３３を介して給湯栓７へ給湯される湯水の流量は前記した２０号相当流量Ｑであり、その温度（給湯設定温度）をＴとする。
【００４９】
ここで、分岐給湯流路８３、給水流路８５および給湯流路３３は混合弁８０に接続されているので、前記した各流量および温度の間には次に示す式３、式４が成立する。

これら式３および式４より、式２に示した給湯必要流量Ｑｓが導出される。
【００５０】
燃焼制御部１０３は、ステップ２１４において前記式２に基づき給湯必要流量Ｑｓを算出し、熱源循環回路３２の湯水の循環量がＱｓとなるように循環水比例弁５１を制御する（図３ステップ２１５参照）。
【００５１】
続いて、燃焼制御部１０３は、燃焼機６に供給するガス量を給湯用のガス量演算式に基づいて算出し、算出した量のガスを燃焼機６へ供給して燃焼制御を行う（以上、図３ステップ２１６，２１７参照）。本実施形態に採用する給湯用のガス量演算式は式５で示される。尚、式５において、Ｋ１，Ｋ２は定数である。また、式５において、燃焼機流量は給湯必要流量Ｑｓである。

【００５２】
式５において、右辺第１項目は、燃焼機６を流動する湯水の流量と、燃焼機６の設定温度および燃焼機６の入口温度の差との積に基づいてＦＦ制御を行う項である。右辺第２項目は、燃焼機６の設定温度と燃焼機６の出口温度との差に基づいてＦＢ制御を行う項である。また、右辺第３項目は、燃焼機６の設定温度と燃焼機６の出口温度との差分を所定時間積算した値に基づいてＦＢ制御を行う項である。
【００５３】
則ち、右辺第１項目は、燃焼機６で加熱される前の流入口４０に流入する湯水の温度に応じて、流出口３７の温度をいち早く設定温度に昇温させるためにガス量を見越して供給する演算項である。また、右辺第２項目は、一般に行われるＦＢ制御の演算項である。更に、右辺第３項目は、燃焼機６の出口温度の変動を所定時間について平均化した値で補正する演算項である。
式５で演算されたガス量Ｇのガスを燃焼機６に供給して燃焼制御することにより、燃焼機６の流出口３７の温度を短時間に設定温度に到達させつつ、しかも、流出する湯水の温度がハンチングすることを抑制した制御を可能にしている。
【００５４】
続いて、燃焼制御部１０３は、分岐給湯流路８３、給水流路８５および給湯流路３３に設けた各温度センサ９２，９３，９５の検知温度を参照しつつ、給湯温度センサ９５の検知温度がリモートコントローラで設定された給湯設定温度となるように、混合弁８０の湯水の混合比率を調整する（図３ステップ２１８参照）。
【００５５】
以上のステップを繰り返すことにより給湯運転が行われる。そして、給湯流路３３の給湯流量センサ８１によるＭＯＱの検知が停止すると、燃焼制御部１０３は、給湯栓７が閉栓されたものと判断し、燃焼機６の燃焼駆動および熱源循環ポンプ４７の駆動を各々停止して給湯運転を終了する（以上、図３ステップ２１０，２１９参照）。
【００５６】
（暖房単独運転の制御）
暖房単独運転時の制御は、図４に示すフローチャートに従って行われる。
リモートコントローラの暖房スイッチがオン操作されると、燃焼制御部１０３は、燃焼機６の設定温度を所定値（本実施形態では、暖房端末要求温度＋２℃）に設定すると共に、暖房循環ポンプ６０を駆動し暖房熱交電磁弁５２を開成する。更に、燃焼機６を燃焼駆動すると共に熱源循環ポンプ４７を駆動する（以上、図４ステップ２３０〜２３６参照）。これにより、熱源循環回路３２および暖房循環回路３５の湯水の循環が始まり、熱源循環回路３２から暖房循環回路３５へ熱エネルギーの供給が開始される。尚、暖房運転の開始時にはハイカットフラグはオフしている。
【００５７】
燃焼制御部１０３は、熱源流量センサ５０の検知流量を監視しつつ、熱源循環回路３２の湯水の流動量が９［リットル／ｍｉｎ］となるように循環水比例弁５１を制御する。これにより、熱源循環回路３２には、燃焼機６の流出口３７から流出する湯水の温度が設定温度（暖房端末要求温度＋２℃）となるように制御されつつ９［リットル／ｍｉｎ］の湯水が循環され、この熱エネルギーが暖房熱交換器４２を介して暖房循環回路３５へ供給されて暖房運転が開始される（図４ステップ２３７参照）。
【００５８】
続いて、燃焼制御部１０３は、燃焼機６に供給するガス量を暖房用のガス量演算式に基づいて算出し、算出した量のガスを燃焼機６へ供給しつつ燃焼制御を行う（以上、図４ステップ２３８，２３９参照）。
本実施形態に採用する暖房用のガス量演算式は式６で示される。尚、式６において、Ｋ３，Ｋ４は定数である。

【００５９】
式６において、右辺第１項目は、燃焼機６の設定温度と燃焼機６の出口温度との差に基づいてＦＢ制御を行う項である。また、右辺第２項目は、燃焼機６の設定温度と燃焼機６の出口温度との差分を所定時間積算した値に基づいてＦＢ制御を行う項である。
【００６０】
則ち、右辺第２項目は、一般に行われるＦＢ制御の演算項である。また、右辺第２項目は、燃焼機６の出口温度の変動を所定時間について平均化した値で補正する演算項である。式６で演算されたガス量Ｇを燃焼機６に供給して燃焼制御することにより、燃焼機６の流出口３７の温度を暖房端末８の要求する熱量に応じて制御することができ、暖房循環回路３５のハイカットの発生が抑制される。
【００６１】
続いて、燃焼制御部１０３は、燃焼機６から流出する湯水の温度の安定判別処理を行う。この処理は、図７の様に、燃焼機６の流出口３７から流出する湯水の温度、則ち、温度センサ３９の検知温度が、ステップ２３３で設定された設定温度に対して（設定温度−２℃）以上の状態が１分間継続したときに安定と判別する処理である。この安定判別処理は、燃焼機６の燃焼制御を開始して３分経過した時点から開始され、８分経過するまで継続する。そして、８分が経過するまでに安定と判別されたときは、直ちに次のステップに進む。また、安定が判別されないまま８分が経過した場合でも、安定したものと見なして次のステップに進む（以上、図４ステップ２４０、図７ステップ２６０〜２６２参照）。
【００６２】
次いで、燃焼制御部１０３は、３０秒間そのまま暖房運転を継続した後に、暖房往路５５を循環する湯水の温度、則ち、温度センサ６４の検知温度を参照する。そして、温度センサ６４の検知温度が（暖房往路設定温度＋５℃）以下のときは、暖房端末への熱供給の過剰状態に至っていないと判別して燃焼機６の設定温度の調節処理に進む（以上、図４ステップ２４１〜２４３参照）。
【００６３】
燃焼機６の設定温度の調節処理は、図８の様に、暖房往路５５を循環する湯水の温度と暖房往路設定温度との温度差に応じて燃焼機６の設定温度を調節する処理である。則ち、暖房往路５５を循環する湯水の温度が（暖房往路設定温度＋４℃）を超えるときは燃焼機６の設定温度を２℃低下させ、（暖房往路設定温度＋１．５℃）を超えるときは燃焼機６の設定温度を１℃だけ低下させる。また、暖房往路５５を循環する湯水の温度が（暖房往路設定温度−４℃）よりも低いときは燃焼機６の設定温度を２℃増加させ、（暖房往路設定温度−１．５℃）よりも低いときは燃焼機６の設定温度を１℃だけ増加させる。また、暖房往路５５を循環する湯水の温度が（暖房往路設定温度−１．５℃）以上、（暖房往路設定温度＋１．５℃）以下のときは、燃焼機６の設定温度をそのまま維持する（以上、図４ステップ２４３、図８ステップ２７０〜２７７参照）。これにより、暖房端末８への熱供給量に応じて燃焼機６の燃焼量がきめ細かく変更設定される。
【００６４】
燃焼制御部１０３は、燃焼機６の設定温度の変更処理を行った結果、調節した設定温度が燃焼機６の設定可能な範囲内であれば、そのままステップ２３０に戻る。また、調節した設定温度が燃焼機６で設定可能な上限または下限から外れるときは、設定温度を上限値または下限値に設定してステップ２３０に戻る（以上、図４ステップ２４４，２４５参照）。そして、ステップ２３８〜２４５の処理を繰り返すことにより、燃焼機６の設定温度を暖房端末の熱要求に応じて調節しつつ暖房制御を継続する。尚、この状態では、ハイカットフラグはオンにされておらず、ステップ２３１からそのままステップ２３８に進む。また、暖房運転中に暖房運転の解除操作が行われると、ステップ２３０からステップ２５０の暖房運転の停止処理に進む。
【００６５】
一方、ステップ２４２において、暖房往路５５を循環する湯水の温度が（暖房往路設定温度＋５℃）を超えるときは、燃焼制御部１０３は、暖房端末８への熱供給が過剰であると判別して暖房循環ポンプ６０を駆動したまま暖房熱交電磁弁５２を閉成し、燃焼機６の燃焼および熱源循環ポンプの駆動を停止する。この際、燃焼制御部１０３は、ハイカットフラグをオンにする。これにより、熱源循環回路３２から暖房循環回路３５への熱エネルギーの供給が遮断されてハイカット状態となる（以上、図４ステップ２４２〜２４８参照）。
【００６６】
ハイカット状態に入ると、暖房循環回路３５の湯水を循環させつつ温度が低下するのを待機する。そして、暖房往路５５の温度センサ６４の検知温度が（暖房往路設定温度−１０℃）よりも低下すると、暖房端末８への熱供給の再開が可能と判別して暖房制御のステップ２３０に戻って同一の処理を繰り返す（図４ステップ２４９参照）。
【００６７】
暖房運転中にリモートコントローラにより暖房運転の解除操作が行われると、暖房熱交電磁弁５２を閉成しすると共に暖房循環ポンプ６０の駆動を停止し、燃焼機６の燃焼および熱源循環ポンプ４７の駆動を停止して一連の暖房運転を終了する（以上、図４ステップ２３０、２５０〜２５２参照）。
【００６８】
（給湯・暖房同時運転時の給湯制御）
同時運転時の給湯制御は、図５に示すフローチャートに従って行われる。
給湯流路３３の給湯流量センサ８１がＭＯＱを検知すると、燃焼制御部１０３は、給湯運転を開始する。給湯運転を開始すると、燃焼制御部１０３は、燃焼機６の設定温度を暖房側制御による設定温度のまま維持する。但し、暖房側の設定温度が６４℃よりも低い場合は６４℃に設定する。そして、燃焼機６を燃焼駆動すると共に、熱源循環ポンプ４７の駆動を開始する（以上、図５ステップ２８０〜２８２参照）。
【００６９】
続いて、燃焼制御部１０３は、給湯流路３３の湯水の流量が１５号相当流量となるように給湯水比例弁８２を制御する（図５ステップ２８３参照）。ここで、１５号相当流量は、前記した給湯単独運転において２０号相当流量を求めた場合と同様にして、式７で算出される。
【００７０】
【数３】

【００７１】
従って、燃焼制御部１０３は、リモートコントローラで設定された給湯設定温度と給水温度センサ９３の検知温度とを参照して、式７に基づいて１５号相当流量Ｑを演算し、給湯流路３３の湯水の流動量が演算結果の１５号相当流量Ｑとなるように給湯水比例弁８２を制御する。
【００７２】
続いて、燃焼制御部１０３は、給湯必要流量Ｑｓを算出する（図５ステップ２８４参照）。ここに、給湯必要流量Ｑｓは、前記した給湯単独運転において算出した場合と同様にして、式８で算出される。
【００７３】
【数４】

【００７４】
続いて、燃焼制御部１０３は、同時運転における暖房側の制御を参照し、暖房必要流量Ｑ１ｓの算出の有無を確認する。暖房必要流量Ｑ１ｓが既に算出されているときは、熱源循環回路３２の湯水の循環量が（Ｑｓ＋Ｑ１ｓ）となるように循環水比例弁５１を制御する（以上、図５ステップ２８５，２９２参照）。
一方、暖房必要流量Ｑ１ｓが算出されていないときは、暖房許容流量Ｑ１を算出し、熱源循環回路３２の湯水の循環量が（Ｑｓ＋Ｑ１）となるように循環水比例弁５１を制御する。ここに、暖房許容流量Ｑ１は、燃焼機６の許容流量Ｑｍａｘ から給湯必要流量Ｑｓを差し引いた値である。従って、熱源循環回路３２の湯水の循環量が許容流量Ｑｍａｘ ＝（Ｑｓ＋Ｑ１）（本実施形態では１０［リットル／ｍｉｎ］）となるように循環水比例弁５１を制御する（以上、図５ステップ２８５〜２８７参照）。
【００７５】
次に、燃焼制御部１０３は、熱源往路３８から分岐給湯流路８３と熱交分岐流路９４とへ流動する湯水が、各々、給湯必要流量Ｑｓと暖房必要流量Ｑ１ｓに分配されるように、比例弁８４の開度制御を行う（図５ステップ２８８参照）。
ここで、本実施形態の加熱装置３では、分岐給湯流路８３および熱交分岐流路９４のいずれにも流量センサを設けていない。このため、各流路８３，９４の流動量の検知を次の様に温度によって検知する制御を採用している。
則ち、図１の様に、分岐給湯流路８３と熱交分岐流路９４へ、各々、給湯必要流量Ｑｓと暖房必要流量Ｑ１ｓの湯水が流動する状態では、給水流路９１を介して集合部Ｆに流量Ｑｓの水が流入する。この集合部Ｆへ流入する流量Ｑｓの水と、熱交分岐流路９４から集合部Ｆへ流入する流量Ｑ１ｓの湯水とが合流して、流量Ｑｔの湯水となって熱源復路４１を燃焼機６へ向けて流動する。
【００７６】
ここで、給水流路９１を流動する水の温度、則ち、温度センサ７６の検知温度をＴｓ（＝Ｔｗ）とし、熱交分岐流路９４から集合部Ｆに流入する湯水の温度、則ち、温度センサ７７の検知温度をＴ１ｓとし、更に、熱源復路４１を流動する湯水の温度、則ち、温度センサ４８の検知温度をＴｔとする。
すると、集合部Ｆにおいて式９、式１０で示す関係が成立する。
給湯必要流量Ｑｓ＋暖房必要流量Ｑ１ｓ ＝Ｑｔ ・・・・・・・（式９）
給湯必要流量Ｑｓ・Ｔｓ＋暖房必要流量Ｑ１ｓ・Ｔ１ｓ＝Ｑｔ・Ｔｔ ・・・（式１０）
これら式９、式１０より式１１が導出される。
【００７７】
【数５】

【００７８】
従って、燃焼制御部１０３は、温度センサ７７の検知温度をＴ１ｓ、温度センサ４８の検知温度をＴｔ、および、温度センサ７６の検知温度をＴｓを参照しつつ、式１１の右辺の値が、左辺の給湯必要流量Ｑｓと暖房必要流量Ｑ１ｓの比率と一致するように比例弁８４を制御する。これにより、ステップ２８８において分岐部Ｅにおける給湯必要流量Ｑｓと暖房必要流量Ｑ１ｓの分配制御を可能にしている。
【００７９】
続いて、燃焼制御部１０３は、給湯単独運転の制御と同様に、燃焼機６に供給するガス量を給湯用のガス量演算式（前記式５）に基づいて算出し、算出した量のガスを燃焼機６へ供給して燃焼制御を行う（以上、図５ステップ２８９，２９０参照）。但し、前記式５において、燃焼機流量は給湯必要流量Ｑｓと暖房必要流量Ｑ１ｓの和である。
【００８０】
そして、燃焼制御部１０３は、分岐給湯流路８３、給水流路８５および給湯流路３３に設けた各温度センサ９２，９３，９５の検知温度を参照しつつ、給湯温度センサ９５の検知温度がリモートコントローラで設定された給湯設定温度となるように、混合弁８０の湯水の混合比率を調整する（図５ステップ２９１参照）。
【００８１】
以上のステップを繰り返すことにより給湯運転が行われる。そして、給湯流路３３の給湯流量センサ８１によるＭＯＱの検知が停止すると、燃焼制御部１０３は、給湯栓７が閉栓されたものと判断して、同時運転時における給湯制御を終了して暖房単独運転に移行する（以上、図５ステップ２８０参照）。
【００８２】
（給湯・暖房同時運転時の暖房制御）
同時運転時の暖房制御は、図６に示すフローチャートに従って行われる。
リモートコントローラの暖房スイッチがオン操作されると、燃焼制御部１０３は、図６の様に、燃焼機６の設定温度を所定値（本実施形態では、暖房端末要求温度＋２℃）に設定し、暖房循環ポンプ６０を駆動すると共に暖房熱交電磁弁５２を開成する。更に、燃焼機６を燃焼駆動すると共に熱源循環ポンプ４７を駆動する。（以上、図６ステップ３００〜３０５参照）。これにより、暖房循環回路３５の湯水が循環を開始し、熱源循環回路３２から暖房循環回路３５へ熱エネルギーの供給が開始される。尚、暖房運転の開始時にはハイカットフラグはオフしている。
【００８３】
燃焼制御部１０３は、熱源流量センサ５０の検知流量を監視しつつ、熱源循環回路３２の湯水の流動量が（Ｑｓ＋Ｑ１）となるように循環水比例弁５１を制御する（図６ステップ３０６参照）。ここで、Ｑｓは給湯側で算出される給湯必要流量であり、Ｑ１は暖房許容流量である。従って、結果的に、循環水比例弁５１は、熱源循環回路３２の湯水の流動量が燃焼機６の許容流量Ｑｍａｘ である１０［リットル／ｍｉｎ］となるように循環水比例弁５１を制御する。
【００８４】
更に、燃焼制御部１０３は、前記式１１に基づいて、分岐部Ｅにおける分岐給湯流路８３と熱交分岐流路９４とへ流動する湯水の分配比が、給湯必要流量Ｑｓと暖房許容流量Ｑ１の比率となるように、比例弁８４の制御を行う（図６ステップ３０９参照）。これにより、熱交分岐流路９４に暖房許容流量Ｑ１の湯水が流動する。
【００８５】
続いて、燃焼制御部１０３は、燃焼機６に供給するガス量を給湯用のガス量演算式に基づいて算出し、算出した量のガスを燃焼機６へ供給して燃焼制御を行う（図６ステップ３１０，３１１参照）。給湯用のガス量演算式は前記式５と同一である。但し、前記式５において、燃焼機流量は給湯必要流量Ｑｓと暖房許容流量Ｑ１の和、則ち、１０［リットル／ｍｉｎ］である。
【００８６】
続いて、燃焼制御部１０３は、燃焼機６から流出する湯水の温度の安定判別処理を行う（図５ステップ３１２参照）。この処理は、前記図５に示した処理と同一である。更に、燃焼制御部１０３は、３０秒間そのまま暖房運転を継続した後に、暖房往路５５を循環する湯水の温度、則ち、温度センサ６４の検知温度を参照する。そして、温度センサ６４の検知温度が（暖房往路設定温度＋５℃）以下のときは、ステップ３１５へ進む（図６ステップ３１３，３１４参照）。
【００８７】
ステップ３１５では、燃焼制御部１０３は、現在の暖房側の流量、則ち、熱交分岐流路９４の湯水の流量が最大値である暖房許容流量Ｑ１か否かを判別する。
熱交分岐流路９４の湯水の流量が最大値の暖房許容流量Ｑ１のときは、そのまま、ステップ３１９の暖房必要流量Ｑ１ｓの算出に進む（以上、図６ステップ３１５，３１９参照）。一方、熱交分岐流路９４の湯水の流量が暖房許容流量Ｑ１よりも低いときは、燃焼機６の設定温度の調節処理に進む（以上、図６ステップ３１５，３１６参照）。
【００８８】
燃焼機６の設定温度の調節処理は、前記図８に示した処理と同一である。
そして、燃焼制御部１０３は、燃焼機６の設定温度の変更処理を行った結果、調節した設定温度が燃焼機６の設定可能な範囲内であれば、そのままステップ３１９へ進む。また、調節した設定温度が燃焼機６で設定可能な上限または下限から外れるときは、設定温度を上限値または下限値に設定してステップ３１９へ進む（以上、図６ステップ３１６〜３１９参照）。
【００８９】
ステップ３１９では、暖房必要流量Ｑ１ｓの算出を行う。暖房必要流量Ｑ１ｓは、式１２で与えられる。
【００９０】
【数６】

【００９１】
式１２は次のようにして導出される。本実施形態の加熱装置３では、燃焼機６の燃焼量の最大値が２０号であり、前記したように、給湯側において１５号分の熱量を消費する。従って、暖房側で消費可能な許容号数は５号である。ここで、暖房側で必要な熱量は式１３で示される。
暖房必要熱量＝暖房必要流量Ｑ１ｓ×温度差Ｔ ・・・（式１３）
但し、式１３において、温度差Ｔは、熱交換器４２の上流側と下流側の温度差、則ち、燃焼機６の流出口３７と流入口４０の間の湯水の温度差である。
従って、温度差Ｔは燃焼機設定温度から給水温度を差し引いた値である。
【００９２】
この暖房必要熱量が５号相当の熱量で賄われることから、式１４が成立する。
暖房必要熱量＝暖房必要流量Ｑ１ｓ×温度差Ｔ＝２５［℃］×５［号］・・（式１４）
この式１４より前記式１２が導出される。
【００９３】
燃焼制御部１０３は、ステップ３１９で暖房必要流量Ｑ１ｓを算出してステップ３００に戻る。以降は、暖房必要流量Ｑ１ｓが既に算出されているので、循環水比例弁５１を給湯必要流量Ｑｓ＋暖房必要流量Ｑ１ｓに制御しつつ暖房運転が継続される。また、前記した暖房制御の開始時や、後述するハイカット時には、循環水比例弁５１を給湯必要流量Ｑｓ＋暖房許容流量Ｑ１に制御しつつ同時運転における暖房制御が継続される。
【００９４】
一方、ステップ３１４において、暖房往路５５を循環する湯水の温度が（暖房往路設定温度＋５℃）を超えるときは、燃焼制御部１０３は、暖房循環ポンプ６０を駆動したまま暖房熱交電磁弁５２を閉成すると共に、循環水比例弁５１の開度および燃焼機６の設定温度を給湯単独運転の制御値に変更する。この際、燃焼制御部１０３は、ハイカットフラグをオンにする（以上、図６ステップ３１４，３２０〜３２２参照）。これにより、熱源循環回路３２から暖房循環回路３５への熱エネルギーの供給が遮断されてハイカット状態となる。
【００９５】
ハイカット状態に入ると、暖房循環回路３５の湯水を循環させつつ温度が低下するのを待機する。そして、暖房往路５５の温度センサ６４の検知温度が（暖房往路設定温度−１０℃）よりも低下すると、暖房端末８への熱供給の再開が可能と判別して暖房制御のステップ３００に戻って同一の処理を繰り返す（図６ステップ３２３参照）。
【００９６】
暖房運転中にリモートコントローラにより暖房運転の解除操作が行われると、暖房熱交電磁弁５２を閉成すると共に暖房循環ポンプ６０の駆動を停止して同時運転における暖房制御を終了して給湯単独運転に戻る（以上、図６ステップ３００，３２４，３２５参照）。
【００９７】
以上説明したように、本実施形態の加熱装置３によれば、給湯および暖房の各々の熱負荷に応じて燃焼機に最適なガス供給を行いつつ燃焼制御して熱供給を行うことが可能である。これにより、給湯時の給湯性能や暖房運転時における頻繁なハイカットの発生などを効果的に防止して安定した運転を行うことが可能となる。また、同時運転から暖房単独運転に移行した際に、燃焼機が燃焼中であれば、給湯端末に応じた燃焼制御を継続させるので、給湯栓の頻繁な開閉に伴う暖房回路への弊害を抑制することができる。これにより、加熱装置３における給湯性能や暖房性能の向上が図られ、使い勝手を向上させることが可能となる。
【００９８】
【実施例】
次に、本発明に係る実施例を図９〜図１６を参照して説明する。
本実施例は、前記実施形態で示した加熱装置３を用いて形成したコージェネレーションシステム１である。本実施例のコージェネレーションシステム１に採用する加熱装置３は、前記実施形態に示した加熱装置３の有する追い焚き機能および暖房機能に加えて、給湯機能およびふろの落とし込み機能を備えると共に、湯水を貯留する貯留タンクを備えた構成である。
【００９９】
図９は、本実施例のコージェネレーションシステム１の流路系統図である。図１０は、図９に示すシステム１が排熱貯湯運転を行う場合の作動原理図である。図１１は、図９に示すシステム１が貯留タンク内の湯水を用いて給湯運転を行う場合の作動原理図である。図１２は、図９に示すシステム１が燃焼機を作動させて給湯を行う場合の作動原理図である。図１３は、図９に示すシステム１が落とし込み運転を行う場合の作動原理図である。図１４は、図９に示すシステム１が追い焚き運転を行う場合の作動原理図である。図１５および図１６は、図９に示すシステム１が暖房運転を行う場合の作動原理図である。
【０１００】
本実施例のコージェネレーションシステム１は、図９の様に、大別して加熱装置３と発電装置２で構成される。発電装置２は、ガスエンジン５（熱源部）を備えたものであり、コージェネレーションシステム１の外部の電気機器へ電力を供給すると共に、発電に伴い発生した排熱により湯水を加熱する。また、加熱装置３は、燃焼機６（熱源部）を備えたものであり、主として給湯栓７へ供給する湯水を加熱したり、温水床暖房、ファンコンベクタ等の暖房端末８などに熱エネルギーを供給する湯水を加熱するものである。
【０１０１】
発電装置２は、大別してガスエンジン５と、ガスエンジン５によって駆動する発電機１０と、ヒータ１１とを備えている。発電装置２において発生した電力は、システム１の外部に設けられた電気機器等の外部負荷や、ヒータ１１（内部負荷）に供給される。発電装置２は、ガスエンジン５を冷却することによって排熱を回収する排熱循環回路１２を備えている。
【０１０２】
排熱循環回路１２は、発電装置２の外部、則ち、加熱装置３側にある排熱熱交換器３０および暖房熱交換器５７を経由して湯水を循環させるものである。排熱循環回路１２は、ガスエンジン５からバイパス分岐点Ａを経て排熱熱交換器３０に向けて湯水を流す排熱往路１３と、その分岐水路であり暖房熱交換器５７に向けて湯水を流す排熱分岐往路６１、並びに、排熱熱交換器３０からガスエンジン５側へと湯水を戻す排熱復路１５と、暖房熱交換器５７から戻る湯水が前記排熱復路１５に合流する排熱分岐復路６２とから構成されている。則ち、ガスエンジン５には排熱熱交換器３０と暖房熱交換器５７とが前記各流路によって並列に接続されている。排熱循環回路１２内を流れる湯水は、排熱復路１５の途中に設けられた排熱循環ポンプ１６によって圧送され、排熱復路１５側から排熱往路１３側へと流動する。排熱復路１５内を流れる湯水は、ガスエンジン５の駆動に伴い発生する熱で加熱されて排熱往路１３へと流出する。
【０１０３】
ガスエンジン５と排熱熱交換器３０とを接続する排熱往路１３の途中には、ヒータ１１が設けられている。ヒータ１１は、発電機１０と外部の電気機器等とを接続する配線１７から分岐された分岐配線１８に接続されている。ヒータ１１には、分岐配線１８を介して外部の電気機器等で消費しきれない余剰電力が供給されており、これにより発電機１０から外部電源（図示せず）への電力の逆潮流が防止されている。則ち、ヒータ１１は、後述する余剰電力制御部１０１によって制御可能なスイッチ２１が設けられており、このスイッチ２１を調整することによりヒータ１１への通電が調整される。
【０１０４】
ガスエンジン５の排熱により加熱され、排熱往路１３内を流れる湯水は、ヒータ１１を通過する際に更に加熱されて排熱熱交換器３０へと流入する。排熱熱交換器３０において熱交換を行い低温となった湯水は、排熱復路１５を介してガスエンジン５へと戻る。
【０１０５】
排熱復路１５の途中には、上記した排熱循環ポンプ１６の他に補水タンク２２とサーモスタット式の三方弁２５とが設けられている。また、三方弁２５は、後述する排熱分岐復路６２に設けられている三方弁２３と連通する連通流路２４に接続されている。さらに、排熱復路１５と排熱往路１３との間には、両者をバイパスするバイパス流路２６が設けられている。補水タンク２２には、外部から水を供給するための給水管２７が設けられており、その途中に設けられている補水弁２８によって補水タンク２２への給水量が調整される。また、三方弁２５は、ガスエンジン５側から排出される湯水の温度に応じて排熱熱交換器３０および暖房熱交換器５７側への湯水の往来を調整するものである。
【０１０６】
さらに具体的には、ガスエンジン５の起動直後等のように、ガスエンジン５側から排出される湯水が所定温度以下である場合には、三方弁２５が作用し、排熱熱交換器３０および暖房熱交換器５７への入水が阻止される。則ち、ガスエンジン５側から排出される湯水が低温である場合、三方弁２５の作用によって排熱熱交換器３０および暖房熱交換器５７から排熱復路１５への通水が阻止されると共に、バイパス流路２６を介して排熱往路１３と排熱復路１５とが連通した閉回路が形成される。そのため、排熱往路１３内を流れる湯水は、バイパス流路２６を介して直接ガスエンジン５側へと流れ込む。
【０１０７】
一方、ガスエンジン５側から排出される湯水が所定温度より高温である場合、三方弁２５の作用によって排熱往路１３内を流れる湯水が、排熱熱交換器３０および暖房熱交換器５７へと流入する。排熱熱交換器３０および暖房熱交換器５７に流入した高温の湯水は、各熱交換器において熱交換を行った後、三方弁２３を介して排熱復路１５へと流入してガスエンジン５側へと戻る。
【０１０８】
加熱装置３は、燃料ガスを燃焼し湯水を加熱する燃焼機６と、排熱循環回路１２内を流れるガスエンジン５の排熱により加熱された湯水と熱交換を行う排熱熱交換器３０と、貯留タンク３１（貯留部）とを備えている。加熱装置３は、熱源循環回路３２と、ガスエンジン５および燃焼機６において発生した熱によって加熱された湯水を給湯栓７を介して外部に供給する給湯回路２９とを備え、これに加えて暖房端末８（熱負荷）等の熱負荷に接続される暖房循環回路３５と、湯水を浴槽に供給して循環させる追い焚き循環回路３６とを有する。
【０１０９】
また、本実施例のコージェネレーションシステム１には、熱源往路３８および熱源復路４１からなる熱源循環回路３２と、貯留タンク３１とから構成される流水回路（閉回路Ｈ）が形成されている。また、コージェネレーションシステム１には、熱源往路３８および熱源復路４１からなる熱源循環回路３２と、貯留タンク３１と、熱源往路３８から分岐された熱交分岐流路９４から構成される流水回路が形成されている。則ち、コージェネレーションシステム１は、閉回路Ｈ、あるいは、閉回路Ｈに熱交分岐流路９４を加えた流路からなる流水回路を備えている。
【０１１０】
熱源循環回路３２は、燃焼機６の流出口３７に接続された熱源往路３８と、燃焼機６の流入口４０に接続された熱源復路４１とを有する。熱源循環回路３２では、熱源往路３８が分岐給湯流路８３とタンク上部配管８７とに分岐される分岐部Ｄの上流側に、比例弁８４が設けられている。また、熱源往路３８は、比例弁８４より上流側の分岐部Ｅにおいてさらに分岐され、分岐部Ｅとエアセパレータ４６とを繋ぐ熱交分岐流路９４が形成されている。
【０１１１】
熱源往路３８は、分岐部Ｄにおいて混合弁８０に繋がる分岐給湯流路８３と、貯留タンク３１に繋がるタンク上部配管８７とに分岐されている。貯留タンク３１には、内部に貯留されている湯水の高さ方向の温度分布を検知するために、最上部温度センサ３４ａ、上部温度センサ３４ｂ、中部温度センサ３４ｃおよび下部温度センサ３４ｄが設けられている。また、熱源復路４１には、上流側から順に、エアセパレータ４６、湯水を循環させる熱源循環ポンプ４７、排熱熱交換器３０、熱源復路４１を流れる湯水の温度を検知する温度センサ４８、流量を検知する熱源流量センサ５０、および、燃焼機６に流入する水量を調整する循環水比例弁５１が接続されている。熱源復路４１の途中にあるエアセパレータ４６は、熱源循環回路３２中に含まれている空気を外部に排出するものであり、貯留タンク３１の下部に設けられたタンク下部配管８９が接続されている。また、排熱熱交換器３０は、上記した発電装置２においてガスエンジン５の駆動に伴い発生した排熱により加熱された湯水と熱交換を行うことにより熱源復路４１を流れる湯水を加熱するものである。そのため、通常ガスエンジン５の駆動中は、排熱熱交換器３０において加熱された湯水が熱源復路４１を介して燃焼機６に流入する。
【０１１２】
熱交換部４５は、熱交分岐流路９４の途中に設けられており、暖房熱交換器４２と暖房熱交電磁弁５２とを有する流路４５ａと、追い焚き熱交換器４３と追い焚き熱交電磁弁５３とを有する流路４５ｂとが並列に接続したものである。そのため、暖房熱交換器４２および追い焚き熱交換器４３への湯水の流動および遮断は、暖房熱交電磁弁５２および追い焚き熱交電磁弁５３の断続によって制御される。
【０１１３】
暖房熱交換器４２に接続されている暖房循環回路３５は、暖房端末８に湯水を供給する暖房往路５５と、暖房端末８側から湯水を戻す暖房復路５６とを有する。暖房往路の途中には、暖房熱交換器４２から流出する湯水の温度を検知する温度センサ６４が設けられている。暖房復路５６の途中には、暖房端末８への湯水の循環を断続する熱動弁５９と、暖房熱交換器５７と、暖房復路５６に湯水を補給する補水タンク５８と、暖房復路５６から補水タンク５８に流入する湯水の温度を検知する温度センサ５４と、暖房復路５６内に湯水を循環させるための暖房循環ポンプ６０が設けられている。また、暖房循環回路３５には、熱動弁５９が閉成状態である場合に暖房循環ポンプ６０等に過負荷が作用するのを防止するべく、暖房往路５５と暖房復路５６とをバイパスするバイパス流路６３が設けられている。
【０１１４】
暖房熱交換器５７には、上記した発電装置２の排熱往路１３から分岐された排熱分岐往路６１と、排熱復路１５から分岐された排熱分岐復路６２とが接続されており、ガスエンジン５の排熱により加熱された高温の湯水が循環する。そのため、暖房端末８において放熱して低温となった湯水は、暖房熱交換器５７において排熱分岐往路６１により供給された高温の湯水と熱交換して加熱される。暖房熱交換器５７において加熱された湯水は、補水タンク５８を経て暖房熱交換器４２に流入し、暖房熱交換器４２での熱交換によりさらに加熱されたのち再び暖房端末８側へと送り込まれる。
【０１１５】
追い焚き熱交換器４３に接続されている追い焚き循環回路３６は、浴槽側に湯水を送り込む追い焚き往路６５と、浴槽側から湯水を戻す追い焚き復路６６とを備えている。追い焚き復路６６の途中には、浴槽内の水位を検知する水位センサ６７と、流動する湯水の温度を検知する温度センサ６９と、追い焚き循環ポンプ６８と、水流スイッチ７０とが設けられている。また、追い焚き復路６６の途中、則ち、追い焚き循環ポンプ６８と水流スイッチ７０との間には、後述する給湯流路３３から分岐された注湯分岐流路７１が接続されている。注湯分岐流路７１には、給湯流路３３側から追い焚き復路６６側への通水のみを許す逆止弁７２と、追い焚き復路６６側に流入する水量を調整する注湯弁７３と、注湯分岐流路７１内を流れる湯水の流量を検知する流量センサ７５とが設けられている。
【０１１６】
上記したように、追い焚き復路６６には、給湯流路３３側からの湯水の流入を許容する注湯分岐流路７１が接続されているため、追い焚き往路６５に加えて追い焚き復路６６からも湯水を浴槽側に落とし込むことができる。
【０１１７】
給湯回路２９は、熱源往路３８の途中で分岐されて混合弁８０に至る分岐給湯流路８３、および、混合弁８０から給湯栓７に至る給湯流路３３と、給水栓（不図示）から混合弁８０に至る給水流路８５、および、給水流路８５の途中から分岐して貯留タンク３１の底部側に至る給水流路９１とを組み合わせて形成される。
【０１１８】
給湯流路３３の途中には、流量センサ８１、比例弁８２および給湯温度センサ９５が設けられている。また、給水流路８５は、途中に減圧弁８８と、混合弁８０側に湯水を導く逆止弁９０と、外部から導入される湯水の温度を検知する給水温度センサ９３が設けられた流路であり、混合弁８０に接続されている。
【０１１９】
給水流路８５の途中には、外部から導入された湯水を貯留タンク３１側に向けて供給する給水流路９１が接続されている。給水流路９１は、貯留タンク３１の底部側に接続されており、途中に給水流路８５側から貯留タンク３１側へ湯水を導く逆止弁８６が設けられている。また、貯留タンク３１の底部には、貯留タンク３１から湯水を排出するタンク下部配管８９が接続されている。タンク下部配管８９は、前記した通り燃焼機６の流入口４０に繋がる熱源復路４１にエアセパレータ４６を介して接続されている。さらに、貯留タンク３１の上部には、分岐給湯流路８３から分岐され、貯留タンク３１への湯水の流出入を行うためのタンク上部配管８７が接続されている。貯留タンク３１には、タンク上部配管８７を通って貯留タンク３１の外部に流出する湯水と略同量の湯水が給水流路９１を介して給水されるため、貯留タンク３１は常に満水状態に維持される。
【０１２０】
本実施例のコージェネレーションシステム１には、発電装置２および加熱装置３の駆動を統括する制御部１００と、余剰電力制御部１０１とを備えたシステム制御部１０２が設けられている。制御部１００は、発電装置２や加熱装置３の燃焼制御部１０３との間で制御に必要な信号を送受信することにより、各センサの検知信号に基づいて弁の開閉を行ったり、ポンプやガスエンジン５、燃焼機６等の駆動を行う。
【０１２１】
ここで、本実施例のシステム１では、運転状態をシステム制御部１０２の制御部１００で統括する。則ち、システム１が給湯や暖房、追い焚き、落とし込みのいずれかの単独運転中である場合や、あるいは、複数の運転が同時に行われている状態を制御部１００で管理している。そして、運転モードに応じて制御部１００から燃焼制御部１０３へ制御信号を送出して必要な燃焼制御を行う。
また、本実施例のシステム１では、暖房単独運転時には、制御部１００から燃焼制御部１０３に対して暖房単独指令信号を送出する。燃焼制御部１０３は、暖房単独指令信号を受信した場合に限って、前記実施形態で述べたように燃焼機６の燃焼パターンを暖房用に切り換え設定し、暖房単独指令信号が伝送されないときは、燃焼パターンを給湯用に切り換え設定する構成とされている。
【０１２２】
また、余剰電力制御部１０１は、コージェネレーションシステム１における電力調整を行うものである。則ち、余剰電力制御部１０１は、外部から供給される電力量や、発電装置２において発生する電力量や、発電装置２に接続された電気機器等における電力消費量を検知し、その余剰電力をヒータ１１において消費させることにより外部電源（図示せず）への電力の逆潮流を防止するものである。則ち、余剰電力制御部１０１は、外部電源への電力の逆潮流を検知し、この検知信号に基づきヒータ１１のスイッチ２１をＯＮ・ＯＦＦさせることによって発電装置２において発生したものの発電装置２に接続されている電気機器等では消費しきれない電力を消費させるものである。
【０１２３】
システム制御部１０２は、上記した各運転に則ってガスエンジン５および燃焼機６を稼働させ、これにより発生する熱によって湯水を加熱するものである。則ち、システム制御部１０２は、湯水の使用状況や、湯水の使用予定、余剰電力制御部１０１において検知された電力状況、則ち発電装置２における発電量やコージェネレーションシステム１およびコージェネレーションシステム１に接続された電気機器等における電力使用状況に応じて制御部１００によりガスエンジン５および燃焼機６の駆動を制御し、湯水の加熱や発電を行う。
【０１２４】
続いて、本実施例のコージェネレーションシステム１における湯水の流れについて説明する。
コージェネレーションシステム１は、システム制御部１０２によって複数の運転状態に制御されるものであり、各運転毎に湯水の流れが異なる。則ち、システム制御部１０２は、貯留タンク３１に湯水を貯留する排熱貯留運転と、給湯栓７から湯水を排出する給湯運転と、浴槽内に湯水を落とし込む落とし込み運転と、浴槽内の湯水を追い焚きする追い焚き運転と、暖房端末８の運転を行う暖房運転のいずれか１つあるいは複数の運転を選択的に行う。
【０１２５】
先ず、排熱貯留運転を行う場合の湯水の流れについて、図１０を参照しながら説明する。排熱貯留運転を行う場合、発電装置２においてガスエンジン５が駆動を開始し、それに伴い排熱循環ポンプ１６が作動して排熱循環回路１２内を湯水が循環し始める。排熱循環回路１２内を流れる湯水は、ガスエンジン５の駆動に伴い発生する排熱により加熱される。また、ガスエンジン５の駆動に伴い、発電機１０において発生した電力のうち、発電機１０に接続されたシステム１の外部にある電気機器等において消費しきれない余剰の電力によりヒータ１１が作動し、排熱往路１３内を流れる湯水がさらに加熱される。
【０１２６】
ガスエンジン５の起動直後等のように、排熱循環回路１２内の湯水が低温である場合、三方弁２５は、連通流路２４を閉成し、排熱復路１５とバイパス流路２６とを連通するように作動する。そのため、排熱往路１３内を流れる湯水は、バイパス流路２６を介して排熱復路１５側へと流れて循環し、排熱熱交換器３０や暖房熱交換器５７側には流れ込まない。そして、ガスエンジン５の駆動に伴って排熱循環回路１２内の湯水が所定の温度以上となると、三方弁２３および三方弁２５が切り替わり、湯水が排熱熱交換器３０内を循環し始める。
【０１２７】
一方、加熱装置３では、熱源循環ポンプ４７が駆動を開始し、貯留タンク３１の底部に設けられたタンク下部配管８９から貯留タンク３１内の湯水が熱源復路４１側に流入する。熱源復路４１内を流れる湯水は、排熱熱交換器３０においてガスエンジン５の排熱やヒータ１１によって加熱された湯水と熱交換を行って加熱された後、燃焼機６の流入口４０から燃焼機６へ流入する。
【０１２８】
排熱貯留運転では燃焼機６は燃焼停止状態であるため、流入口４０から流入した湯水は、燃焼機６内を素通りし、流出口３７に接続された熱源往路３８へと流出する。ここで、熱源往路３８に流入する湯水の温度、則ち温度センサ３９の検知温度が所定温度に達していない場合は、分岐給湯流路８３の比例弁８４が閉成され、暖房熱交電磁弁５２あるいは追い焚き熱交電磁弁５３のうち少なくともいずれか一方（本実施例では暖房熱交電磁弁５３）が閉成される。これにより、貯留タンク３１には、所定温度に達していない湯水が流入せず、燃焼機６を出た湯水は熱交換部４５側の流路を流れて熱源循環回路３２内を循環する。則ち、熱源往路３８内を流れる湯水が低温である間は、熱源往路３８の途中にある比例弁８４の上流側と、貯留タンク３１の下流側とをバイパスする熱交分岐流路９４および熱交換部４５に湯水を循環させ、湯水の温度上昇を待機する。
【０１２９】
一方、熱源往路３８内を流れる湯水が所定温度以上となると、比例弁８４が開成されると共に、熱交換部４５の暖房熱交電磁弁５２および追い焚き熱交電磁弁５３の双方が閉成される。また、ここで混合弁８０は、分岐給湯流路８３に対して閉成されている。そのため、排熱熱交換器３０において加熱され、所定温度に達している湯水は、貯留タンク３１の上部に接続されたタンク上部配管８７から流入し、貯留タンク３１内に貯留される。則ち、貯留タンク３１の底部に接続されたタンク下部配管８９から排出された湯水が、排熱熱交換器３０において加熱された後、貯留タンク３１の頂部に接続されたタンク上部配管８７から流入する。そのため、貯留タンク３１内に貯留されている湯水は、下方から上方に向けて次第に高温となっている。則ち、貯留タンク３１内に貯留されている湯水は、上下方向に層状の温度分布を形成している。貯留タンク３１内に貯留されている湯水の略全体が所定温度以上となると、排熱貯湯運転による湯水の貯留が完了する。従って、貯留タンク３１の下部温度センサ３４ｄが所定の温度に達すると、システム制御部１０２は下部温度センサ３４ｄよりも上方に貯留されている湯水が所定温度に達しているものと判断し、排熱貯湯運転を完了させる。
【０１３０】
続いて、コージェネレーションシステム１が給湯運転を行う場合の湯水の流れを図１１を参照しながら説明する。貯留タンク３１内に湯水が充分貯留されている場合、給湯栓７が開栓されると、給水流路８５を介して外部から供給される低温の水の一部は、混合弁８０に向けて供給される。一方、外部から供給される低温の水の一部は、給水流路８５から分岐された給水流路９１を介して貯留タンク３１の底部に流入する。ここで、熱源復路４１の途中に設けられた熱源循環ポンプ４７は停止あるいは低回転で作動しており、比例弁８４は閉成あるいは大幅に開度が絞られている。従って、貯留タンク３１の底部から湯水が流入しても、湯水は殆ど熱源復路４１をはじめとする閉回路Ｈ側には流出しない。そのため、貯留タンク３１の底部から湯水が流入すると、この湯水によって貯留タンク３１内に貯留されている湯水が上方に押し上げられる。その結果、貯留タンク３１の上部側の高温の湯水がタンク上部配管８７から排出される。タンク上部配管８７から排出された湯水は分岐給湯流路８３内を流れ、混合弁８０側へと流れる。
【０１３１】
混合弁８０は、分岐給湯流路８３に対して開成されているため、タンク上部配管８７から排出された湯水は混合弁８０に流入する。混合弁８０に流入した高温の湯水は、給水流路８５を介して供給された低温の水と混合されて適温となり、給湯流路３３を介して給湯栓７から排出される。則ち、貯留タンク３１から流出し、分岐給湯流路８３内を流れる湯水の温度を検知する温度センサ９２と、外部から供給される水の温度を検知する給水温度センサ９３と、混合弁８０において混合され排出される湯水の温度を検知する給湯温度センサ９５との検知温度に応じて、給湯栓７から排出される湯水の温度が適温となるように混合弁８０における湯水の混合比率が調整される。混合弁８０において混合された湯水は、給湯流路３３および給湯栓７を介して外部に供給される。
【０１３２】
一方、貯留タンク３１内の湯水が低温である場合は、図１２に示すように燃焼機６により湯水が加熱され、この湯水が給湯栓７から排出される。則ち、貯留タンク３１内の湯水が低温である状態で給湯栓７が開栓されると、熱源循環ポンプ４７が起動し、比例弁８４が開成される。また、熱交換部４５にある暖房熱交電磁弁５２および追い焚き熱交電磁弁５３が閉成され、熱源往路３８から熱交分岐流路９４への湯水の流入が阻止される。更に、混合弁８０は、熱源往路３８を流れる湯水が流入する分岐給湯流路８３および外部から導入される湯水が流れる給水流路８５に対して開成される。そのため、外部から供給される低温の水の一部は、給水流路８５を介して混合弁８０に至り、混合弁８０に接続された給湯流路３３へと流れ込む。また、外部から供給された湯水の残部は、給水流路８５から分岐された給水流路９１を通じて貯留タンク３１の下部から供給される。流量センサ８１によって給湯流路３３における水流が検知されると、燃焼機６が燃焼作動を開始する。
【０１３３】
給水流路９１を介して外部から貯留タンク３１の下部に流入した湯水は、タンク下部配管８９から熱源復路４１を介して燃焼機６に流入する。燃焼機６に流入した湯水は、燃焼作動に伴い発生した熱によって加熱された後、熱源往路３８および分岐給湯流路８３を通じて混合弁８０に流入する。混合弁８０に流入した高温の湯水は、外部から給水流路８５を介して供給された湯水と混合されて適温に調整され、給湯流路３３および給湯栓７を介して外部に供給される。
【０１３４】
上記したように、給湯栓７が開栓されると、システム制御部１０２は、コージェネレーションシステム１を給湯運転で作動させ、貯留タンク３１内の湯水または燃焼機６によって加熱された湯水を用いて給湯を行う。給湯栓７が閉栓され、流量センサ８１が水流を検知しなくなると、システム制御部１０２は燃焼機６の燃焼作動等を停止させ一連の動作を完了する。
【０１３５】
続いて、コージェネレーションシステム１が落とし込み運転を行う場合の湯水の流れを図１３を参照しながら説明する。本実施例のコージェネレーションシステム１では、落とし込み運転を行う際に、追い焚き往路６５に加えて追い焚き復路６６からも湯水を浴槽に落とし込む構成を採っている。
【０１３６】
本実施例のコージェネレーションシステム１では、注湯弁７３が開成され、流量センサ７５が水流を検知すると、落とし込み運転を開始する。貯留タンク３１内に湯水が充分貯留されている場合、落とし込み運転が開始されると、上記した給湯運転と同様にして浴槽へ落とし込まれる湯水の温度が調整される。則ち、給水流路８５を介して外部から供給される低温の水の一部が、混合弁８０に向けて供給される。その一方で、外部から供給される湯水の残部は、給水流路９１を介して貯留タンク３１の底部から流入する。これに伴い、貯留タンク３１の上部側に貯留されている高温の湯水がタンク上部配管８７から排出され、混合弁８０に流れ込む。
【０１３７】
混合弁８０に流入した高温の湯水は、給水流路８５を介して供給された低温の水と混合されて適温に調整され、給湯流路３３へと流出する。給湯流路３３へ流入した湯水は、給湯流路３３から分岐された注湯分岐流路７１を流れ、追い焚き復路６６に流入する。ここで、落とし込み運転の場合は追い焚き循環ポンプ６８が停止しているため、追い焚き復路６６に流入した湯水の一部は、追い焚き復路６６を介して浴槽内に流入する。また、注湯分岐流路７１から追い焚き復路６６へと流入した湯水の残部は、追い焚き熱交換器４３を迂回して追い焚き往路６５から浴槽へと流入する。水位センサ６７によって浴槽内の水位が所定の水位になったことが検知されると、注湯弁７３が閉成され、一連の落とし込み運転が完了する。
【０１３８】
続いて、浴槽内の湯水の追い焚きを行う追い焚き運転における湯水の流れについて図１４に示す作動原理図を参照しながら説明する。
追い焚き運転における各部の詳細な制御は、前記実施形態に示した加熱装置３における制御と同一である。追い焚き運転では、燃焼機６における燃焼作動により加熱された湯水と、浴槽内の湯水が循環する追い焚き循環回路３６との熱交換により浴槽内の湯水を追い焚きする。
【０１３９】
さらに詳細に説明すると、コージェネレーションシステム１が追い焚き運転を開始すると、追い焚き循環ポンプ６８が駆動する。これに伴い、水流スイッチ７０が追い焚き復路６６における湯水の流量が所定量であることを検知すると、熱源復路４１に設けられた熱源循環ポンプ４７が起動し、燃焼機６が起動する。またこの時、暖房熱交電磁弁５２は閉成され、追い焚き熱交電磁弁５３が開成される。これにより、追い焚き運転においては、燃焼機６から排出される湯水は、図１４に示すように熱源往路３８から熱交換部４５の流路４５ｂを経由し、熱源復路４１を通過して燃焼機６に戻る経路で循環する。則ち、追い焚き運転においては、燃焼機６において加熱された高温の湯水が流路４５ｂに設けられた追い焚き熱交換器４３を通過して循環する。追い焚き循環ポンプ６８の駆動に伴い追い焚き循環回路３６内を循環する湯水は、追い焚き熱交換器４３において燃焼機６において加熱された高温の湯水と熱交換を行い加熱される。
そして、リモートコントローラにより追い焚き運転のオフ操作が行われたり、追い焚き復路６６の温度センサ６９がリモートコントローラによる設定温度に達すると、一連の追い焚き運転を終了する。
【０１４０】
続いて、暖房端末８等の熱負荷を駆動させる暖房運転における湯水の流れについて図１５および図１６を参照しながら説明する。
暖房運転における各部の詳細な制御は、前記実施形態に示した加熱装置３における制御と同一である。コージェネレーションシステム１が暖房運転を開始すると、暖房循環ポンプ６０が起動し、暖房循環回路３５内を湯水が循環をはじめる。ここで、温度センサ５４の検知温度、則ち暖房端末８側から戻る湯水の温度が所定温度以下である場合には、暖房循環回路３５内を循環する湯水を加熱すべくガスエンジン５が起動する。また、暖房端末８側から戻る湯水の温度が極めて低い場合や、暖房端末８における設定温度が高い場合等は、ガスエンジン５に加えて燃焼機６が起動する。則ち、暖房運転では、暖房熱交換器５７における熱交換によって暖房循環回路３５内を循環する湯水を加熱し、更に場合によっては、暖房熱交換器４２における熱交換を行うことによって暖房循環回路３５内を循環する湯水を加熱する。
【０１４１】
さらに具体的には、図１５の様に、発電装置２のガスエンジン５が起動すると、排熱循環ポンプ１６が作動して排熱循環回路１２内を湯水が循環する。排熱循環回路１２内を流れる湯水は、ガスエンジン５の駆動に伴い発生する排熱により加熱され、高温となる。また、ガスエンジン５の駆動に伴い発電機１０において発生した電力によりヒータ１１が駆動し、排熱往路１３内を流れる湯水がさらに加熱される。
【０１４２】
排熱循環回路１２内の湯水が低温である間は、三方弁２３およびサーモスタット式の三方弁２５の作用により排熱往路１３とバイパス流路２６と排熱復路１５とで構成される閉回路内を湯水が循環する。排熱循環回路１２内を流れる湯水が所定温度以上に加熱されると、三方弁２３およびサーモスタット式の三方弁２５の作用により、湯水が排熱分岐往路６１および排熱分岐復路６２内を流れ、高温の湯水が暖房熱交換器５７に供給される。暖房端末８側から暖房復路５６を介して戻る湯水は、暖房熱交換器５７において発電装置２側から供給される高温の湯水と熱交換を行い加熱される。ここで、暖房熱交換器５７の下流側にある温度センサ５４の検知温度が暖房端末８の設定温度である場合には、暖房熱交換器５７において加熱された湯水を暖房熱交換器４２側に送り込み、暖房熱交換器４２に接続された暖房往路５５を介して暖房端末８に供給する。
【０１４３】
一方、暖房端末８側から戻る湯水の温度が低い場合や、暖房端末８における設定温度が高い場合、則ち、暖房熱交換器５７において熱交換を行うだけでは暖房端末８の設定温度に到達しない場合には、図１６の様に、燃焼機６の駆動が開始されると共に熱源循環ポンプ４７が駆動を開始する。熱源流量センサ５０が熱源循環回路３２における流水を検知すると、燃焼機６における燃焼作動が開始される。燃焼機６における燃焼作動によって加熱され、高温となった湯水は、熱交換部４５の流路４５ａにある暖房熱交換器４２を通過して燃焼機６側へと戻り、暖房循環回路３５を介して暖房端末８へ熱供給を行う。
そして、リモートコントローラにより暖房運転のオフ操作が行われると、一連の追い焚き運転を終了する。
【０１４４】
尚、上記実施例では、コージェネレーションシステム１において各運転を単独で行う場合を例示したが、本発明はこのような単独運転に限定されるものではなく、前記実施形態に示した追い焚き・暖房同時運転や、給湯・暖房同時運転など、各運転を同時に行うことが可能である。
【０１４５】
上記実施例では、湯水を加熱する熱源部としてガスエンジン５と燃焼機６とを備えたコージェネレーションシステム１を例示したが、更に多くの熱源部を設けることも可能である。則ち、主として貯留タンク３１内の湯水を加熱する熱源部、並びに、主として給湯や暖房、追い焚きに用いられる湯水を加熱する熱源部を各々複数ずつ設けた構成を採ることも可能である。
【０１４６】
また、上記実施例では、前記図１０に示したように、発電装置２による排熱を利用した貯留運転を行う例を示したが、本発明はこのような構成に限られるものではなく、例えば、燃焼機６を駆動して追い焚き運転を行いつつ貯留タンク３１へ湯水の貯留を行ったり、あるいは、燃焼機６を駆動して暖房運転を行いつつ貯留タンク３１へ湯水の貯留を行うことも可能である。
更に、例えば、発電装置２に故障が発生したような場合に、排熱利用に代えて、燃焼機６を駆動して貯留運転を行うことも可能である。同様に、発電装置２の故障時に、前記図１５に示した排熱利用による暖房に代えて燃焼機６を駆動して暖房を行うことも可能である。
【０１４７】
【発明の効果】
請求項１〜４に記載の発明によれば、給湯および暖房の各熱負荷に応じて燃焼機を最適な燃焼量で燃焼させつつ熱供給を行うことができ、運転性能を向上させつつ安定した燃焼制御を行う加熱装置を提供できる。
請求項５，６に記載の発明によれば、請求項１〜４に記載の加熱装置を用いてトータルエネルギー効率を向上させ、システム構築を容易にしたコージェネレーションシステムを提供できる。
【図面の簡単な説明】
【図１】本発明の実施形態に係る加熱装置の流路系統図である。
【図２】図１に示す加熱装置の給湯運転および暖房運転に係る制御を示すフローチャートである。
【図３】図１に示す加熱装置の給湯単独運転の制御を示すフローチャートである。
【図４】図１に示す加熱装置の暖房単独運転の制御を示すフローチャートである。
【図５】図１に示す加熱装置の給湯・暖房同時運転時における給湯制御を示すフローチャートである。
【図６】図１に示す加熱装置の給湯・暖房同時運転時における暖房制御を示すフローチャートである。
【図７】図４，図６のフローチャートにおける燃焼機給湯温度の安定判別処理を示すフローチャートである。
【図８】図４，図６のフローチャートにおける燃焼機設定温度の調節処理を示すフローチャートである。
【図９】本発明の実施例に係るコージェネレーションシステムの流路系統図である。
【図１０】図９のコージェネレーションシステムにおいて、排熱貯湯運転を行う場合の作動原理図である。
【図１１】図９のコージェネレーションシステムにおいて、貯留タンクに貯留された湯水による給湯運転を行う場合の作動原理図である。
【図１２】図９のコージェネレーションシステムにおいて、燃焼機を駆動して給湯運転を行う場合の作動原理図である。
【図１３】図９のコージェネレーションシステムにおいて、ふろの落とし込み運転を行う場合の作動原理図である。
【図１４】図９のコージェネレーションシステムにおいて、ふろの追い焚き運転を行う場合の作動原理図である。
【図１５】図９のコージェネレーションシステムにおいて、発電装置の排熱を利用して暖房運転を行う場合の作動原理図である。
【図１６】図９のコージェネレーションシステムにおいて、発電装置の排熱と燃焼機の加熱による暖房運転を行う場合の作動原理図である。
【符号の説明】
１ コージェネレーションシステム
２ 発電装置
３ 加熱装置
６ 燃焼機（熱源部）
７ 給湯端末（給湯栓）
８ 暖房端末
１２ 排熱循環回路
２９ 給湯回路
３０ 排熱熱交換部（排熱熱交換器）
３１ 貯留部（貯留タンク）
３２ 熱源循環回路
３３，８３ 給湯流路（分岐給湯流路）
３５ 暖房回路（暖房循環回路）
３６ 追い焚き回路（追い焚き循環回路）
４２ 熱交換器（暖房熱交換器）
４３ 熱交換器（追い焚き熱交換器）
８５，９１ 給水流路
１０２ システム制御部
１０３ 燃焼制御部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a heating device, and more particularly, to a device that performs optimal heat supply according to a heat load. The invention proposed at the same time relates to a cogeneration system using this heating device.
[0002]
[Prior art]
Heating devices having many operating functions such as hot water supply and bath dropping, reheating, and heating have been developed. Such a heating device has a configuration in which a hot water supply circuit, a reheating circuit, a heating circuit, and the like having different systems are connected to a combustor, and a heat medium circulating in each circuit is directly heated by the combustor to supply thermal energy. Have been.
[0003]
In recent years, a so-called cogeneration system has been developed in which a power generation device is provided in addition to a heating device, and waste heat accompanying power generation is recovered and used. Since such a system reuses the exhaust heat of the power generation device, instead of concentrating a plurality of heat supply circuits of different systems in the combustor to heat the heat medium, the combustor is used in one circulation circuit. A plurality of heat sources and a plurality of heat loads are provided, and heat energy is supplied to each heat load via a heat medium heated by the heat source.
[0004]
By the way, when performing a hot water supply operation, it is required to raise the temperature of hot water to be supplied to a target set temperature in a short time immediately after the start of the operation. On the other hand, when performing a heating operation such as hot water floor heating, immediately after the start of the operation, the combustion amount of the combustor is suppressed and the temperature is gradually increased to the set temperature, and thereafter, the combustion of the combustor according to the heat absorption state of the heating terminal is performed. The amount needs to be finely controlled.
[0005]
[Problems to be solved by the invention]
However, conventional heating devices and cogeneration systems do not employ control for switching the temperature rise pattern of the heat medium heated by the combustor in accordance with the hot water supply operation or the heating operation.
That is, in conventional heating devices and cogeneration systems, in order to improve hot water supply performance, only control is performed such that the temperature of the heat medium heated by the combustor rises to the set temperature in a short time. During the heating operation, the set temperature was changed, but the heating medium temperature rise pattern was the same. For this reason, during the heating operation, the heat supply becomes excessive, and a high cut state in which the heat supply is cut off tends to occur frequently, and stable heat supply cannot be performed.
[0006]
The present invention has been proposed in view of the above circumstances, and has as its object to provide a heating device capable of performing stable heat supply to heat loads having different heat absorption. Another object of the invention proposed at the same time is to provide a cogeneration system configured using the heating device.
[0007]
[Means for Solving the Problems]
The invention according to claim 1, which is proposed to achieve the above object, is a hot water supply terminal provided outside a heat source circulation circuit for circulating hot water heated by one or more heat source units including a combustor. The hot water supply circuit connected to the heater and the heating circuit connected to the externally provided heating terminal are connected directly or via a heat exchanger to supply hot water to the hot water supply terminal or supply heat energy to the heating terminal or both of them. During heating alone operation for supplying heat energy to the heating circuit alone, the combustion device burns the combustor in a combustion pattern corresponding to the heat energy required by the heating terminal of the heating circuit. During operation other than the operation, the combustor burns in a combustion pattern corresponding to the thermal energy required by the hot water supply terminal of the hot water supply circuit.
[0008]
Here, the combustion pattern referred to in the present invention refers to a curve in which the temperature of hot water flowing out of the combustor rises with time when the hot water flowing in the heat source circulation circuit is heated by the combustor. . For example, a combustion pattern that raises the temperature of hot and cold water flowing out of the combustor to a target set temperature in a very short time from the start of combustion, or a combustion pattern that raises the temperature to a set temperature a predetermined time after the start of combustion, is used. Can be.
[0009]
According to the present invention, when performing the hot water supply operation requiring the hot water supply performance, the temperature of the outflowing hot water is raised to the set temperature in a short time by performing combustion in a state of a high combustion amount immediately after the start of the hot water supply operation. be able to. In addition, when performing a heating operation in which the heat supply is likely to be excessive when the heat supply amount is rapidly increased, the combustion is performed with a lower combustion amount than when hot water is supplied, thereby preventing an excessive heat supply state from occurring. it can.
Further, in the simultaneous operation of hot water supply and heating, combustion is performed with the amount of combustion in the case of performing the hot water supply operation, so that simultaneous operation can be performed while ensuring hot water discharge performance.
[0010]
In the present invention, various control methods can be used to change the combustion pattern of the combustor. For example, feedback control (Feedback Control: hereinafter referred to as FB control) for controlling the amount of combustion so that the temperature becomes a target set temperature while monitoring the temperature of the hot and cold water heated by the combustor. Can be.
Also, a feedforward control (Feedforward Control: below) that controls the amount of combustion so that the outflow temperature reaches the set temperature in a short time while monitoring the temperature and flow rate of the inflowing hot water in addition to the temperature of the hot water flowing out of the combustor. FF control). It is also possible to perform control combining FB control and FF control.
Furthermore, when performing FB control, it is possible to perform control based on the difference between the target set temperature and the temperature of the hot and cold water that is heated by the combustor and flows out, or control based on a value obtained by integrating the difference for a predetermined time. is there.
[0011]
According to a second aspect of the present invention, in the heating device according to the first aspect, when the operation mode shifts to the heating only operation from another operation except the heating only operation, the combustion machine stops the combustion in the heating only operation. During this period, the combustion pattern of the combustor is switched from the combustion pattern corresponding to the hot water supply terminal to the combustion pattern corresponding to the heating terminal.
[0012]
Here, according to the invention described in claim 1, when the hot water supply operation is started during the single heating operation, the combustion pattern of the combustor is switched to the combustion pattern corresponding to the hot water supply terminal. That is, the hot and cold water flowing out of the combustor is sharply fluctuated toward the set temperature. For this reason, heat supply tends to be excessive in the heating terminal, and a high cut state in which heat supply to the heating terminal is interrupted is likely to occur.
According to the present invention, even if the hot water supply operation ends during the simultaneous operation and shifts to the heating only operation, the combustion pattern is maintained as it is during the combustion of the combustor. Thus, even when the hot water supply operation is frequently repeated, the combustion pattern does not change, and stable heat supply can be continued.
[0013]
According to a third aspect of the present invention, in the heating apparatus according to the first or second aspect, a reheating circuit connected to a bath terminal is circulated through a heat exchanger in parallel with the hot water supply circuit and the heating circuit via a heat exchanger. It is configured to be connected to a circuit.
[0014]
ADVANTAGE OF THE INVENTION According to this invention, the heat of the hot water heated in the heat source circulation circuit can be transmitted to the hot water flowing through the reheating circuit via the heat exchanger, and a heating device having a reheating function can be configured. Can be.
[0015]
According to a fourth aspect of the present invention, in the heating device according to any one of the first to third aspects, the hot water supply circuit includes a hot water supply channel for supplying hot water to a hot water supply terminal or a bath terminal provided outside and a hot water supply flow path provided outside. A water supply passage for receiving water from the provided water supply terminal is formed by combining the water supply passages, and a storage unit is provided between the hot water supply passage and the water supply passage for storing hot water heated by the heat source circulation circuit. .
[0016]
According to the present invention, the hot water heated in the heat source part of the heat source circulation circuit is stored in the storage part via the hot water supply flow path, and the low-temperature water in the storage part is returned to the heat source circulation circuit through the water supply flow path for heating. By doing so, the heated hot water can be stored in the storage section.
In addition, a hot water supply operation is performed in which high-temperature hot water stored in the storage unit is discharged to the hot water supply terminal through the hot water supply channel without passing through the heat source circulation circuit, and water is supplied to the heat source circulation circuit through the water supply flow channel. be able to.
[0017]
It is also possible to perform a hot water supply / storage operation in which a part of the hot water heated in the heat source part of the heat source circulation circuit is discharged to a hot water supply terminal through a hot water supply flow path, and the remaining part of the heated hot water is stored in the storage part. It is possible. Further, it is also possible to perform a hot water supply operation in which the hot water heated in the heat source portion of the heat source circulation circuit and the high-temperature water stored in the storage portion are simultaneously discharged to the hot water supply terminal via the hot water supply passage.
[0018]
According to a fifth aspect of the present invention, there is provided a cogeneration system including a heating device according to any one of the first to fourth aspects and a power generation device for supplying electric power to electric equipment, wherein the power generation device is configured to generate electric power. It has a waste heat circulation circuit for exchanging waste heat generated by heat exchange with the heat medium and circulating the waste heat, and a waste heat heat exchange part is interposed between the waste heat circulation circuit and the heat source circulation circuit, and the heat source part One is configured to be a waste heat exchange unit.
[0019]
According to the present invention, since the heat of the heat medium circulating in the exhaust heat circulation circuit of the power generation device is transmitted to the heat medium circulating in the heat source circulation circuit of the heating device via the exhaust heat exchange section, the heat source circulation circuit One heat source part is formed thereon. This makes it possible to recover the waste heat that has been conventionally discarded and reuse it for raising the temperature of the heat medium circulating in the heat source circulation circuit, and to construct a cogeneration system with improved total energy efficiency.
[0020]
According to a sixth aspect of the present invention, there is provided the cogeneration system according to the fifth aspect, further comprising a system control unit that controls a heating device and a power generation device, and the heating device includes a combustion control unit that performs combustion control of a combustor. In addition, when the cogeneration system performs the heating only operation, the system control unit sends a heating only command signal to the combustion control unit.
[0021]
According to the present invention, when the heating control command signal is transmitted from the system control unit, the combustion control unit performs combustion control by switching the combustion pattern of the combustor to a combustion pattern corresponding to the heating terminal, and performs the heating control command signal. Is not transmitted, the combustion pattern of the combustor is switched to the combustion pattern corresponding to the hot water supply terminal to perform combustion control. Thus, the combustion control unit can switch and set the combustion pattern based on the operation information grasped by the system control unit, and the system can be easily constructed.
[0022]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a flow path diagram of the heating device 3 of the present embodiment. FIG. 2 is a flowchart illustrating the control of the heating device 3. FIG. 3 is a flowchart showing the control of the hot water supply independent operation in FIG. FIG. 4 is a flowchart showing the control of the single heating operation in FIG. FIG. 5 is a flowchart showing hot water supply control during simultaneous hot water supply / heating operation in FIG. FIG. 6 is a flowchart showing the heating control at the time of simultaneous operation of hot water supply and heating in FIG. FIGS. 7 and 8 are flowcharts showing in detail some steps of the heating control of FIGS. 4 and 6.
[0023]
The heating device 3 of this embodiment has a hot water supply function and a heating function. As shown in FIG. 1, a hot water supply operation to a hot water tap 7 provided outside and heating of a hot water floor heating device and a fan convector, etc. The terminal 8 has a heating function.
[0024]
The heating device 3 includes a combustion control unit 103 that controls the control of each unit and a plurality of hot and cold water circuits. That is, as shown in FIG. 1, a heat source circulating circuit 32 for circulating hot and cold water (heat medium) heated by a combustor 6 (heat source portion) that receives supply of city gas (natural gas) and burns, and a heating device 3 A heating circuit (heating circulation circuit) 35 connected to a heating terminal 8 provided outside the heater and circulating hot water, and a hot water supply circuit 29 connected to the hot water tap 7 and a hot water tap (not shown) for supplying hot water. Have.
Then, the temperature and flow rate of hot and cold water flowing in each circuit are detected by a sensor and transmitted to the combustion control unit 103, and a control signal generated by the control circuit unit is sent to a flow control valve or a solenoid valve provided in each unit, By controlling the temperature and flow rate of hot and cold water in each circuit, hot water is supplied or thermal energy is supplied to a heat load.
[0025]
The heat source circulation circuit 32 is formed by connecting a heat exchange part 45 serving as a heat load and a hot water supply circuit 29 between a heat source outward path 38 extending from the outlet 37 of the combustor 6 and a heat source return path 41 extending from the inlet 40. Circuit. The heat exchange section 45 is provided with a heating heat exchanger 42 and a heating heat exchange solenoid valve 52.
[0026]
Further, the hot water supply circuit 29 includes a branch hot water supply passage 83 branched at a branch portion E in the middle of the heat source outward path 38 and reaching the mixing valve 80, a hot water supply passage 33 extending from the mixing valve 80 to the hot water tap 7, and a water tap. It is formed by combining a water supply flow path 85 extending from a (not shown) to the mixing valve 80 and a water supply flow path 91 branching from the middle of the water supply flow path 85 and reaching the heat source return path 41.
[0027]
A temperature sensor 39 for detecting the temperature of hot and cold water which is heated by the combustor 6 and flows out is provided in the heat source outward path 38 close to the outlet 37 of the combustor 6, and the heat source circulation pump is provided in the heat source return path 41 in order from the upstream side. 47, a temperature sensor 48, a heat source flow sensor 50, and a circulating water proportional valve 51 are provided.
The detection signals of the temperature sensors 39 and 48 and the heat source flow sensor 50 are sent to the combustion control unit 103, and the combustion control unit 103 sets the temperature of the combustor 6 to adjust the temperature and flow rate of the hot and cold water circulating in the heat source circulation circuit 32. Further, the opening degree of the circulating water proportional valve 51 is controlled.
[0028]
The heating and heat exchange solenoid valve 52 is an opening and closing control valve driven by a solenoid, and controls opening and closing of the flow of hot water circulating in the heat source circulation circuit 32 to the heating heat exchanger 42 to perform connection and cutoff as a heat load. The circulating water proportional valve 51 is a proportional control valve driven by a step motor, and continuously variably controls the flow rate of hot and cold water circulating in the heat source circulating circuit 32. The heat source circulation pump 47 is a pump for forcibly circulating hot and cold water in the heat source circulation circuit 32. The heat source flow rate sensor 50 is a sensor that detects the flow rate of hot and cold water in the heat source circulation circuit 32.
[0029]
A flow sensor 81, a proportional valve 82, and a hot water temperature sensor 95 are provided in the middle of the hot water supply passage 33. The water supply flow path 85 is provided with a pressure reducing valve 88, a check valve 90 for guiding hot and cold water to the mixing valve 80, and a water supply temperature sensor 93 for detecting the temperature of hot and cold water introduced from outside. And is connected to the mixing valve 80.
[0030]
The heating circulation circuit 35 is a circulation circuit configured with the heating heat exchanger 42 that receives supply of thermal energy from hot and cold water circulating in the heat source circulation circuit 32 as a heat source and the heating terminal 8 as a heat load. The heating circulation circuit 35 is a circulation circuit formed by connecting the heating terminals 8 to ends of a heating outward path 55 and a heating return path 56 extending from the secondary side of the heating heat exchanger 42.
[0031]
The heating forward path 55 and the heating return path 56 extend outside the heating device 3. The heating outward path 55 extends from the secondary end of the heating heat exchanger 42 directly to the outside of the heating device 3. The heating return path 56 extends from the other end on the secondary side of the heating heat exchanger 42 to the outside of the heating device 3 via a heating circulation pump 60 and a thermal valve (intermittent control valve) 59.
[0032]
Between the heating forward path 55 and the heating return path 56, a bypass passage 63 that bypasses both paths is provided inside the heating device 3. That is, a bypass passage 63 is provided between the heating return path 56 and the heating outward path 55 between the heat valve 59 and the heating circulation pump 60, and separately from the long heating circulation circuit 35 passing through the heating terminal 8. A short circulation circuit is formed inside the heating device 3 via the bypass passage 63.
The bypass passage 63 is a pipe having a smaller passage cross-sectional area than the heating forward path 55 and the heating return path 56. When the heating circulating pump 60 is driven with the thermal valve 59 closed, the bypass flow path 63 It has a function of circulating hot and cold water through the passage 63 to prevent seizure of the pump 60.
[0033]
The heating terminal 8 includes a plurality of heating terminals such as a hot water heating device and a fan convector. Although not shown in FIG. 1, a heating outward path 55 and a heating return path 56 via a thermal valve 59 are connected to each terminal, and the thermal valve 59 of the heating terminal to be operated is opened to open the heating circulation circuit 35. Is formed, heating is performed by selectively circulating hot and cold water to a plurality of heating terminals.
[0034]
A temperature sensor 64 for detecting the temperature of the circulating hot and cold water is provided at a position located on the heating heat exchanger 42 side of the bypass passage 63 in the heating outward path 55. The detection signal of the temperature sensor 64 is sent to the combustion control unit 103, and the set temperature of the combustor 6 and the opening control of the circulating water proportional valve 51 are controlled to control the temperature of the hot and cold water circulating in the heating circulation circuit 35 to a predetermined value. Done.
[0035]
The heating device 3 has the above configuration, and circulates the heat source circulation circuit 32 by forcibly circulating the hot water with the heat source circulation pump 47 while controlling the set temperature of the combustor 6 and the opening of the circulating water proportional valve 51. The temperature and flow rate of hot and cold water can be adjusted and controlled.
That is, the heat source circulation circuit 32 has a function as a heat source that supplies hot water to the hot water supply circuit 29 while adjusting the temperature and flow rate of the circulating hot water and also supplies heat to the heat exchange unit 45.
[0036]
Next, the control of the hot water supply operation and the heating operation performed in the heating device 3 shown in FIG. 1 will be described with reference to the flow path system diagram of FIG. 1 and the flowcharts of FIGS. In the description, a schematic control flow in the heating device 3 will be described first with reference to the flowchart of FIG. 2, and details of each control will be described with reference to flowcharts of FIGS. 3 to 8. Further, in the following description, the control shown in the flowchart of FIG. 2 is divided as the main routine from the control of FIGS. 3 to 8, but this division is provided for convenience of description, and is used for creating a control program. It does not impose any restrictions.
[0037]
In the heating device 3 of the present embodiment, when the hot-water tap 7 is opened and the hot-water supply operation is started, the combustor 6 performs combustion while receiving a controlled amount of gas supply for hot-water supply and performs the hot-water supply alone operation (FIG. 2 steps 200, 201, 207). Further, when a heating operation is performed by a remote controller (not shown), the combustor 6 performs combustion while receiving a controlled amount of gas supply for heating to perform heating alone operation (steps 200, 203, and 203 in FIG. 2). 204, 208).
[0038]
When the heating operation is performed during the hot water supply operation, or when the hot water tap 7 is opened during the heating operation, the combustor 6 burns while receiving a controlled amount of gas supply for the hot water supply and simultaneously performs the hot water supply and the heating. Operation is performed (see steps 200 to 202 in FIG. 2).
[0039]
When the hot-water tap 7 is closed during the simultaneous operation of hot water supply and heating, the hot water supply operation is terminated and the operation shifts to the single heating operation. At the time of the transition to the heating only operation, when the combustor 6 is burning by the heating control, the combustion control is continued while controlling the amount of gas supplied to the combustor 6 for hot water supply (see steps 203 to 206 in FIG. 2). ).
[0040]
On the other hand, after the transition to the heating only operation, if the combustion of the combustor 6 is stopped due to a decrease in the heat demand on the heating terminal 8 side or the occurrence of a high cut (described later) that shuts off the heat supply to the heating circulation circuit 35, Then, the amount of gas supplied to the combustor 6 is switched for heating. Thereafter, the combustor 6 burns while receiving a controlled amount of gas supply for heating to continue the heating alone operation (see steps 203 to 205 and 208 in FIG. 2).
[0041]
Next, each control of the hot water supply alone operation, the heating alone operation, the hot water supply operation during the simultaneous operation, and the heating operation during the simultaneous operation in FIG. 2 will be described in detail with reference to FIGS. 1 and 3 to 8. .
[0042]
(Control during hot water supply alone operation)
The control at the time of the hot water supply independent operation is performed according to the flowchart shown in FIG.
When the hot water supply flow sensor 81 in the hot water supply passage 33 detects a minimum operation water amount (hereinafter, referred to as MOQ), the combustion control unit 103 determines that the hot water tap 7 has been opened and starts the hot water supply operation. (See step 210 in FIG. 3).
When the hot water supply operation is started, the combustion control unit 103 sets the set temperature of the combustor 6 to 70 ° C., drives the combustor 6 to burn, and starts driving the heat source circulation pump 47 (step 211 in FIG. 3). , 212).
[0043]
Subsequently, the combustion control unit 103 controls the hot water proportional valve 82 such that the flow rate of hot water in the hot water flow path 33 becomes a flow rate corresponding to No. 20 (see step 213 in FIG. 3). The maximum combustion amount of the combustor 6 employed in this embodiment is No. 20.
Here, No. 1 is a basic unit indicating the amount of heat required to raise the temperature of 1 liter / min water by 25 ° C., and the No. 1 equivalent flow rate is the product of the flow rate of the water and the temperature increase value of No. 1. It is a value indicating the flow rate when Therefore, the No. 20 equivalent flow rate is expressed by Equation 1.
[0044]
(Equation 1)

[0045]
Accordingly, in step 213, the combustion control unit 103 calculates the No. 20 equivalent flow rate Q based on Equation 1 with reference to the hot water supply set temperature set by the remote controller and the detection temperature of the water supply temperature sensor 93, and The hot water proportional valve 82 is controlled so that the flow rate of the hot water in the flow path 33 becomes the flow rate Q corresponding to No. 20 of the calculation result.
[0046]
Subsequently, the combustion control unit 103 calculates the required hot water supply flow rate Qs (see step 214 in FIG. 3). Here, the required hot water supply flow rate Qs is the flow rate of hot water required to be supplied from the combustor 6 via the branch hot water supply passage 83 in order to supply hot water from the hot water tap 7 at a flow rate equivalent to No. 20 shown in the above formula 1. And given by equation 2.
[0047]
(Equation 2)

[0048]
Equation 2 is derived as follows. As shown in FIG. 1, the flow rate of hot water that needs to be supplied from the combustor 6 to the mixing valve 80 via the branch hot water supply flow path 83 is the hot water supply required flow rate Qs, and the temperature thereof is Ts. Also, the flow rate and the temperature of the water supplied to the mixing valve 80 via the water supply passage 85 are denoted by Qw and Tw, respectively. The flow rate of hot water supplied from the mixing valve 80 to the hot water tap 7 through the hot water supply passage 33 is the flow rate Q corresponding to the aforementioned No. 20, and its temperature (hot water supply set temperature) is T.
[0049]
Here, since the branch hot water supply flow path 83, the water supply flow path 85, and the hot water supply flow path 33 are connected to the mixing valve 80, the following equations 3 and 4 are established between the respective flow rates and temperatures. .

From these equations 3 and 4, the required hot water supply flow rate Qs shown in equation 2 is derived.
[0050]
The combustion control unit 103 calculates the required hot water supply flow rate Qs based on the equation 2 in step 214, and controls the circulating water proportional valve 51 so that the circulation amount of hot water in the heat source circulation circuit 32 becomes Qs (step 215 in FIG. 3). reference).
[0051]
Subsequently, the combustion control unit 103 calculates the amount of gas to be supplied to the combustor 6 based on the hot water supply gas amount calculation formula, and supplies the calculated amount of gas to the combustor 6 to perform combustion control (the above. , FIG. 3, steps 216, 217). The equation for calculating the amount of gas for hot water supply used in the present embodiment is shown in Equation 5. In Equation 5, K1 and K2 are constants. Further, in Equation 5, the combustor flow rate is the hot water supply required flow rate Qs.

[0052]
In Equation 5, the first item on the right side is a term for performing FF control based on the product of the flow rate of hot and cold water flowing through the combustor 6 and the difference between the set temperature of the combustor 6 and the inlet temperature of the combustor 6. The second item on the right side is a term for performing FB control based on the difference between the set temperature of the combustor 6 and the outlet temperature of the combustor 6. The third item on the right side is a term for performing FB control based on a value obtained by integrating the difference between the set temperature of the combustor 6 and the outlet temperature of the combustor 6 for a predetermined time.
[0053]
That is, the first item on the right side is foreseeing the gas amount in order to quickly raise the temperature of the outlet 37 to the set temperature in accordance with the temperature of the hot water flowing into the inlet 40 before being heated by the combustor 6. Is an operation term to be supplied. The second item on the right side is an operation term of the FB control that is generally performed. Further, the third item on the right side is a calculation term for correcting the fluctuation of the outlet temperature of the combustor 6 with a value averaged over a predetermined time.
By supplying the gas having the gas amount G calculated by the equation 5 to the combustor 6 and controlling the combustion, the temperature of the outlet 37 of the combustor 6 can reach the set temperature in a short time, and the hot and cold water Hunting is suppressed.
[0054]
Subsequently, the combustion control unit 103 refers to the detection temperatures of the temperature sensors 92, 93, and 95 provided in the branch hot water supply channel 83, the water supply flow channel 85, and the hot water supply channel 33, and detects the detected temperature of the hot water temperature sensor 95. The mixing ratio of the hot and cold water of the mixing valve 80 is adjusted so that the temperature becomes the hot water supply set temperature set by the remote controller (see step 218 in FIG. 3).
[0055]
The hot water supply operation is performed by repeating the above steps. Then, when the detection of the MOQ by the hot water supply flow rate sensor 81 in the hot water supply flow path 33 is stopped, the combustion control unit 103 determines that the hot water tap 7 is closed, and drives the combustion of the combustor 6 and the drive of the heat source circulation pump 47. Are stopped to terminate the hot water supply operation (see steps 210 and 219 in FIG. 3).
[0056]
(Control of heating alone operation)
The control during the sole heating operation is performed according to the flowchart shown in FIG.
When the heating switch of the remote controller is turned on, the combustion control unit 103 sets the set temperature of the combustor 6 to a predetermined value (in the present embodiment, the required heating terminal temperature + 2 ° C.), and sets the heating circulation pump 60 to ON. It drives and opens the heating heat exchange solenoid valve 52. Further, the burner 6 is driven to burn and the heat source circulation pump 47 is driven (see steps 230 to 236 in FIG. 4). Thereby, circulation of hot water in the heat source circulation circuit 32 and the heating circulation circuit 35 starts, and supply of heat energy from the heat source circulation circuit 32 to the heating circulation circuit 35 starts. At the start of the heating operation, the high cut flag is off.
[0057]
The combustion control unit 103 controls the circulating water proportional valve 51 so that the flow rate of hot water in the heat source circulation circuit 32 becomes 9 [liter / min] while monitoring the detection flow rate of the heat source flow sensor 50. Accordingly, 9 [liter / min] hot water is supplied to the heat source circulation circuit 32 while controlling the temperature of the hot water flowing out from the outlet 37 of the combustor 6 to the set temperature (the required heating terminal temperature + 2 ° C). The heat energy is circulated, and the heat energy is supplied to the heating circulation circuit 35 via the heating heat exchanger 42 to start the heating operation (see step 237 in FIG. 4).
[0058]
Subsequently, the combustion control unit 103 calculates the amount of gas to be supplied to the combustor 6 based on a gas amount calculation formula for heating, and performs combustion control while supplying the calculated amount of gas to the combustor 6 (the above). , FIG. 4 steps 238, 239).
An equation for calculating the amount of gas for heating employed in the present embodiment is shown in Equation 6. In Equation 6, K3 and K4 are constants.

[0059]
In Equation 6, the first item on the right side is a term for performing FB control based on the difference between the set temperature of the combustor 6 and the outlet temperature of the combustor 6. The second item on the right side is a term for performing FB control based on a value obtained by integrating a difference between a set temperature of the combustor 6 and an outlet temperature of the combustor 6 for a predetermined time.
[0060]
That is, the second item on the right side is an operation term of FB control generally performed. The second item on the right side is a calculation term for correcting the fluctuation of the outlet temperature of the combustor 6 with a value averaged over a predetermined time. By supplying the gas amount G calculated by the expression 6 to the combustor 6 and controlling the combustion, the temperature of the outlet 37 of the combustor 6 can be controlled according to the heat amount required by the heating terminal 8. The occurrence of high cut in the circulation circuit 35 is suppressed.
[0061]
Subsequently, the combustion control unit 103 performs a stability determination process of the temperature of the hot and cold water flowing out of the combustor 6. In this process, as shown in FIG. 7, the temperature of the hot and cold water flowing out of the outlet 37 of the combustor 6, that is, the temperature detected by the temperature sensor 39 is set to the set temperature set in step 233 by (set temperature− This is a process for determining that the state is stable when the state of 2 ° C. or more continues for one minute. This stability determination process is started from the point in time when three minutes have elapsed since the start of the combustion control of the combustor 6, and is continued until eight minutes have passed. If it is determined that the state is stable before eight minutes elapse, the process immediately proceeds to the next step. Even when eight minutes have elapsed without determining stability, the process proceeds to the next step on the assumption that the stability has been achieved (see step 240 in FIG. 4 and steps 260 to 262 in FIG. 7).
[0062]
Next, after continuing the heating operation as it is for 30 seconds, the combustion control unit 103 refers to the temperature of the hot and cold water circulating in the heating forward path 55, that is, the temperature detected by the temperature sensor 64. When the temperature detected by the temperature sensor 64 is equal to or lower than (heating forward path set temperature + 5 ° C.), it is determined that the heat supply to the heating terminal is not in an excessive state, and the process proceeds to the adjustment processing of the set temperature of the combustor 6 ( As described above, refer to steps 241 to 243 in FIG.
[0063]
The process of adjusting the set temperature of the combustor 6 is a process of adjusting the set temperature of the combustor 6 according to the temperature difference between the temperature of the hot and cold water circulating in the heating forward path 55 and the set temperature of the heating forward path, as shown in FIG. . That is, when the temperature of the hot and cold water circulating in the heating outward path 55 exceeds (heating outward setting temperature + 4 ° C), the set temperature of the combustor 6 is decreased by 2 ° C, and when the temperature exceeds (heating outward path setting temperature + 1.5 ° C). Reduces the set temperature of the combustor 6 by 1 ° C. Further, when the temperature of the hot and cold water circulating in the heating outward path 55 is lower than (heating outward path setting temperature −4 ° C.), the set temperature of the combustor 6 is increased by 2 ° C. When the temperature is low, the set temperature of the combustor 6 is increased by 1 ° C. When the temperature of the hot and cold water circulating in the heating forward path 55 is equal to or higher than (heating forward path setting temperature −1.5 ° C.) and equal to or lower than (heating forward path setting temperature + 1.5 ° C.), the set temperature of the combustor 6 is maintained as it is. (See step 243 in FIG. 4 and steps 270 to 277 in FIG. 8). Thereby, the combustion amount of the combustor 6 is finely changed and set according to the heat supply amount to the heating terminal 8.
[0064]
As a result of performing the process of changing the set temperature of the combustor 6, if the adjusted set temperature is within the settable range of the combustor 6, the combustion control unit 103 returns to step 230 as it is. If the adjusted set temperature deviates from the upper limit or the lower limit that can be set by the combustor 6, the set temperature is set to the upper limit or the lower limit, and the process returns to step 230 (see steps 244 and 245 in FIG. 4). Then, by repeating the processing of steps 238 to 245, the heating control is continued while adjusting the set temperature of the combustor 6 according to the heat demand of the heating terminal. In this state, the high cut flag is not turned on, and the process proceeds from step 231 to step 238 as it is. In addition, if the operation of canceling the heating operation is performed during the heating operation, the process proceeds from step 230 to step 250 for stopping the heating operation.
[0065]
On the other hand, when the temperature of the hot and cold water circulating in the heating outward path 55 exceeds (heating outward path setting temperature + 5 ° C.) in step 242, the combustion control unit 103 determines that the heat supply to the heating terminal 8 is excessive. While the heating circulation pump 60 is driven, the heating heat exchange solenoid valve 52 is closed, and the combustion of the combustor 6 and the driving of the heat source circulation pump are stopped. At this time, the combustion control unit 103 turns on the high cut flag. As a result, the supply of heat energy from the heat source circulation circuit 32 to the heating circulation circuit 35 is cut off, and a high-cut state is established (see steps 242 to 248 in FIG. 4).
[0066]
When entering the high cut state, the system waits for the temperature to decrease while circulating the hot and cold water in the heating circuit 35. Then, when the temperature detected by the temperature sensor 64 of the heating outgoing path 55 becomes lower than (heating outgoing path set temperature−10 ° C.), it is determined that the heat supply to the heating terminal 8 can be restarted, and the process returns to the heating control step 230. The same processing is repeated (see step 249 in FIG. 4).
[0067]
When the remote controller performs the heating operation release operation during the heating operation, the heating and heat exchange electromagnetic valve 52 is closed, the driving of the heating circulation pump 60 is stopped, and the combustion of the combustor 6 and the heat source circulation pump 47 are stopped. The driving is stopped to end a series of heating operations (see steps 230 and 250 to 252 in FIG. 4).
[0068]
(Hot water supply control during simultaneous operation of hot water supply and heating)
Hot water supply control during simultaneous operation is performed according to a flowchart shown in FIG.
When the hot water supply flow rate sensor 81 in the hot water supply passage 33 detects the MOQ, the combustion control unit 103 starts the hot water supply operation. When the hot water supply operation is started, the combustion control unit 103 maintains the set temperature of the combustor 6 at the set temperature by the heating-side control. However, when the set temperature on the heating side is lower than 64 ° C., the temperature is set to 64 ° C. Then, the combustor 6 is driven to burn, and the driving of the heat source circulation pump 47 is started (see steps 280 to 282 in FIG. 5).
[0069]
Subsequently, the combustion control unit 103 controls the hot water proportional valve 82 so that the flow rate of hot water in the hot water flow path 33 becomes a flow rate corresponding to No. 15 (see step 283 in FIG. 5). Here, the No. 15 equivalent flow rate is calculated by Expression 7 in the same manner as in the case where the No. 20 equivalent flow rate is obtained in the above-described hot water supply independent operation.
[0070]
[Equation 3]

[0071]
Therefore, the combustion control unit 103 calculates the No. 15 equivalent flow rate Q based on Equation 7 with reference to the hot water supply set temperature set by the remote controller and the temperature detected by the water supply temperature sensor 93, and The hot water proportional valve 82 is controlled so that the flow rate of hot water is equal to the No. 15 equivalent flow rate Q of the calculation result.
[0072]
Subsequently, the combustion control unit 103 calculates the required hot water supply flow rate Qs (see step 284 in FIG. 5). Here, the required hot water supply flow rate Qs is calculated by Expression 8 in the same manner as in the case of the above-described hot water supply independent operation.
[0073]
(Equation 4)

[0074]
Subsequently, the combustion control unit 103 refers to the control on the heating side in the simultaneous operation and confirms whether or not the required heating flow rate Q1s has been calculated. When the required heating flow rate Q1s has already been calculated, the circulating water proportional valve 51 is controlled such that the amount of hot water circulated in the heat source circulation circuit 32 becomes (Qs + Q1s) (see steps 285 and 292 in FIG. 5).
On the other hand, when the required heating flow rate Q1s has not been calculated, the allowable heating flow rate Q1 is calculated, and the circulating water proportional valve 51 is controlled such that the amount of hot water circulated in the heat source circulation circuit 32 becomes (Qs + Q1). Here, the heating allowable flow rate Q1 is a value obtained by subtracting the hot water supply required flow rate Qs from the allowable flow rate Qmax of the combustor 6. Accordingly, the circulating water proportional valve 51 is controlled such that the amount of hot water circulated in the heat source circulation circuit 32 becomes the permissible flow rate Qmax = (Qs + Q1) (10 [liter / min] in the present embodiment) (step 285 in FIG. 5). 287).
[0075]
Next, the combustion control unit 103 causes the hot and cold water flowing from the heat source outward path 38 to the branch hot water supply flow path 83 and the heat exchange branch flow path 94 to be distributed to the hot water supply required flow rate Qs and the heating required flow rate Q1s, respectively. The opening control of the proportional valve 84 is performed (see step 288 in FIG. 5).
Here, in the heating device 3 of the present embodiment, neither the branch hot water supply channel 83 nor the heat exchange branch channel 94 is provided with a flow rate sensor. For this reason, control for detecting the flow amount of each of the flow paths 83 and 94 based on the temperature as follows is adopted.
That is, as shown in FIG. 1, when hot water flows at the required hot water supply flow rate Qs and the required heating flow rate Q1s flow to the branch hot water supply flow path 83 and the heat exchange branch flow path 94, respectively, via the water supply flow path 91. Water having a flow rate Qs flows into the section F. The water having the flow rate Qs flowing into the collecting section F and the hot water having the flow rate Q1s flowing into the collecting section F from the heat exchange branch flow path 94 merge into the hot water having the flow rate Qt, and the heat source return path 41 passes through the heat source return path 41. Flow toward.
[0076]
Here, the temperature of the water flowing in the water supply passage 91, that is, the detection temperature of the temperature sensor 76 is Ts (= Tw), and the temperature of the hot water flowing into the collecting portion F from the heat exchange branch passage 94, that is, The temperature detected by the temperature sensor 77 is T1s, and the temperature of the hot and cold water flowing through the heat source return path 41, that is, the temperature detected by the temperature sensor 48 is Tt.
Then, the relations represented by Expressions 9 and 10 are established in the collecting part F.
Hot water supply required flow rate Qs + heating required flow rate Q1s = Qt (Equation 9)
Hot water supply required flow rate Qs · Ts + Heating required flow rate Q1s · T1s = Qt · Tt (Equation 10)
Equation 11 is derived from Equations 9 and 10.
[0077]
(Equation 5)

[0078]
Therefore, the combustion control unit 103 refers to the detected temperature of the temperature sensor 77 as T1s, the detected temperature of the temperature sensor 48 as Tt, and the detected temperature of the temperature sensor 76 as Ts. The proportional valve 84 is controlled so as to match the ratio of the required hot water supply flow rate Qs to the required heating flow rate Q1s. Thereby, in step 288, the distribution control of the hot water supply required flow rate Qs and the heating required flow rate Q1s in the branch portion E is enabled.
[0079]
Subsequently, the combustion control unit 103 calculates the amount of gas to be supplied to the combustor 6 based on the hot water supply gas arithmetic expression (Equation 5) in the same manner as in the control of the hot water supply alone operation. Is supplied to the combustor 6 to perform combustion control (see steps 289 and 290 in FIG. 5). However, in Equation 5, the combustor flow rate is the sum of the hot water supply required flow rate Qs and the heating required flow rate Q1s.
[0080]
Then, the combustion control unit 103 determines the detected temperature of the hot water supply temperature sensor 95 while referring to the detected temperatures of the temperature sensors 92, 93, and 95 provided in the branch hot water supply passage 83, the water supply passage 85, and the hot water supply passage 33. The mixing ratio of the hot and cold water of the mixing valve 80 is adjusted so as to reach the hot water supply set temperature set by the remote controller (see step 291 in FIG. 5).
[0081]
The hot water supply operation is performed by repeating the above steps. When the detection of the MOQ by the hot water supply flow rate sensor 81 in the hot water supply passage 33 stops, the combustion control unit 103 determines that the hot water tap 7 is closed, terminates the hot water supply control in the simultaneous operation, and performs heating only. The operation shifts to operation (see step 280 in FIG. 5).
[0082]
(Heating control during simultaneous operation of hot water supply and heating)
The heating control during the simultaneous operation is performed according to the flowchart shown in FIG.
When the heating switch of the remote controller is turned on, the combustion control unit 103 sets the set temperature of the combustor 6 to a predetermined value (heating terminal required temperature + 2 ° C. in this embodiment), as shown in FIG. The heating circulation pump 60 is driven and the heating heat exchange solenoid valve 52 is opened. Further, the combustion unit 6 is driven to burn and the heat source circulation pump 47 is driven. (See steps 300 to 305 in FIG. 6). Thereby, the hot and cold water in the heating circulation circuit 35 starts to circulate, and the supply of heat energy from the heat source circulation circuit 32 to the heating circulation circuit 35 is started. At the start of the heating operation, the high cut flag is off.
[0083]
The combustion control unit 103 controls the circulating water proportional valve 51 so that the flow rate of hot water in the heat source circulation circuit 32 becomes (Qs + Q1) while monitoring the detection flow rate of the heat source flow rate sensor 50 (see step 306 in FIG. 6). . Here, Qs is a required hot water supply flow rate calculated on the hot water supply side, and Q1 is a heating allowable flow rate. Therefore, as a result, the circulating water proportional valve 51 controls the circulating water proportional valve 51 so that the flow rate of the hot water in the heat source circulation circuit 32 becomes 10 [liter / min] which is the allowable flow rate Qmax of the combustor 6. .
[0084]
Further, the combustion control unit 103 determines that the distribution ratio of the hot water flowing to the branch hot water supply flow path 83 and the heat exchange branch flow path 94 in the branch part E is based on the above equation 11, and the required hot water supply flow rate Qs and the allowable heating flow rate Q1 (Step 309 in FIG. 6). Thereby, the hot and cold water having the allowable heating flow rate Q1 flows through the heat exchange branch flow path 94.
[0085]
Subsequently, the combustion control unit 103 calculates the amount of gas to be supplied to the combustor 6 based on a hot water supply gas amount calculation formula, and supplies the calculated amount of gas to the combustor 6 to perform combustion control (FIG. 6 steps 310, 311). The formula for calculating the amount of gas for hot water supply is the same as the above formula 5. However, in Equation 5, the combustor flow rate is the sum of the hot water supply required flow rate Qs and the allowable heating flow rate Q1, that is, 10 [liter / min].
[0086]
Subsequently, the combustion control unit 103 performs a stability determination process of the temperature of the hot and cold water flowing out of the combustor 6 (see step 312 in FIG. 5). This process is the same as the process shown in FIG. Further, after continuing the heating operation for 30 seconds, the combustion control unit 103 refers to the temperature of the hot and cold water circulating in the heating outward path 55, that is, the temperature detected by the temperature sensor 64. When the temperature detected by the temperature sensor 64 is equal to or lower than (heating forward path set temperature + 5 ° C.), the process proceeds to step 315 (see steps 313 and 314 in FIG. 6).
[0087]
In step 315, the combustion control unit 103 determines whether or not the current flow rate on the heating side, that is, the flow rate of hot and cold water in the heat exchange branch flow path 94 is the maximum heating allowable flow rate Q1.
When the flow rate of the hot and cold water in the heat exchange branch flow path 94 is the maximum allowable heating flow rate Q1, the process directly proceeds to the calculation of the required heating flow rate Q1s in step 319 (see steps 315 and 319 in FIG. 6). On the other hand, when the flow rate of the hot or cold water in the heat exchange branch flow path 94 is lower than the allowable heating flow rate Q1, the process proceeds to the process of adjusting the set temperature of the combustor 6 (see steps 315 and 316 in FIG. 6).
[0088]
The process of adjusting the set temperature of the combustor 6 is the same as the process shown in FIG.
Then, as a result of performing the process of changing the set temperature of the combustor 6, if the adjusted set temperature is within the settable range of the combustor 6, the combustion control unit 103 proceeds to step 319 as it is. If the adjusted set temperature deviates from the upper limit or the lower limit that can be set in the combustor 6, the set temperature is set to the upper limit or the lower limit, and the process proceeds to step 319 (see steps 316 to 319 in FIG. 6).
[0089]
In step 319, the required heating flow rate Q1s is calculated. The heating required flow rate Q1s is given by Expression 12.
[0090]
(Equation 6)

[0091]
Equation 12 is derived as follows. In the heating device 3 of the present embodiment, the maximum value of the combustion amount of the combustor 6 is No. 20, and as described above, the heat amount corresponding to No. 15 is consumed on the hot water supply side. Therefore, the allowable number of consumables on the heating side is five. Here, the amount of heat required on the heating side is represented by Expression 13.
Heating required heat = Heating required flow Q1s × Temperature difference T (Equation 13)
However, in Expression 13, the temperature difference T is the temperature difference between the upstream side and the downstream side of the heat exchanger 42, that is, the temperature difference between hot water and cold water between the outlet 37 and the inlet 40 of the combustor 6.
Therefore, the temperature difference T is a value obtained by subtracting the feed water temperature from the set temperature of the combustor.
[0092]
Since the heating necessary heat amount is covered by the heat amount corresponding to No. 5, Expression 14 is established.
Heating required heat = Heating required flow Q1s × Temperature difference T = 25 [° C] × 5 [No.] (Equation 14)
The above equation (12) is derived from the equation (14).
[0093]
The combustion control unit 103 calculates the required heating flow rate Q1s in step 319, and returns to step 300. Thereafter, since the required heating flow Q1s has already been calculated, the heating operation is continued while controlling the circulating water proportional valve 51 to the required hot water supply flow Qs + the required heating flow Q1s. At the start of the heating control described above or at the time of a high cut described later, the heating control in the simultaneous operation is continued while controlling the circulating water proportional valve 51 to the required hot water supply flow Qs + the allowable heating flow Q1.
[0094]
On the other hand, in step 314, when the temperature of the hot and cold water circulating in the heating outgoing path 55 exceeds (heating outgoing path set temperature + 5 ° C.), the combustion control unit 103 operates the heating and heat exchange electromagnetic valve 52 while the heating circulating pump 60 is driven. At the same time, the opening degree of the circulating water proportional valve 51 and the set temperature of the combustor 6 are changed to control values for the hot water supply independent operation. At this time, the combustion control unit 103 turns on the high cut flag (see steps 314, 320 to 322 in FIG. 6). Thereby, the supply of heat energy from the heat source circulation circuit 32 to the heating circulation circuit 35 is cut off, and a high cut state is set.
[0095]
When entering the high cut state, the system waits for the temperature to decrease while circulating the hot and cold water in the heating circuit 35. Then, when the temperature detected by the temperature sensor 64 in the heating outward path 55 becomes lower than (heating outward path set temperature−10 ° C.), it is determined that the heat supply to the heating terminal 8 can be restarted, and the process returns to the heating control step 300. The same processing is repeated (see step 323 in FIG. 6).
[0096]
When the heating operation is canceled by the remote controller during the heating operation, the heating and heat exchange solenoid valve 52 is closed, the driving of the heating circulation pump 60 is stopped, and the heating control in the simultaneous operation is ended, and the hot water supply alone operation is performed. (See steps 300, 324, and 325 in FIG. 6).
[0097]
As described above, according to the heating device 3 of the present embodiment, it is possible to perform heat control by performing combustion control while performing optimal gas supply to the combustor in accordance with each heat load of hot water supply and heating. is there. This makes it possible to effectively prevent hot water supply performance at the time of hot water supply and frequent occurrence of high cuts at the time of the heating operation, and perform stable operation. In addition, when simultaneous operation is shifted to heating alone operation, if the combustor is burning, the combustion control according to the hot water supply terminal is continued, thereby suppressing the adverse effect on the heating circuit due to frequent opening and closing of hot water taps. can do. Thereby, the hot water supply performance and the heating performance of the heating device 3 are improved, and the usability can be improved.
[0098]
【Example】
Next, an embodiment according to the present invention will be described with reference to FIGS.
The present example is a cogeneration system 1 formed using the heating device 3 shown in the above embodiment. The heating device 3 employed in the cogeneration system 1 of this embodiment has a hot water supply function and a bath dropping function in addition to a reheating function and a heating function of the heating device 3 described in the above embodiment, and also supplies hot and cold water. It is a configuration provided with a storage tank for storing.
[0099]
FIG. 9 is a flow path diagram of the cogeneration system 1 of the present embodiment. FIG. 10 is an operation principle diagram in the case where the system 1 shown in FIG. 9 performs a waste heat storage operation. FIG. 11 is an operation principle diagram when the system 1 shown in FIG. 9 performs a hot water supply operation using hot water in a storage tank. FIG. 12 is an operation principle diagram when the system 1 shown in FIG. 9 operates the combustor to supply hot water. FIG. 13 is an operation principle diagram when the system 1 shown in FIG. 9 performs the drop-in operation. FIG. 14 is an operation principle diagram when the system 1 shown in FIG. 9 performs the reheating operation. 15 and 16 are operation principle diagrams when the system 1 shown in FIG. 9 performs a heating operation.
[0100]
The cogeneration system 1 according to the present embodiment is roughly divided into a heating device 3 and a power generation device 2 as shown in FIG. The power generation device 2 includes a gas engine 5 (heat source unit), and supplies electric power to electric devices outside the cogeneration system 1 and heats hot and cold water by waste heat generated by power generation. Further, the heating device 3 includes a combustor 6 (heat source unit), and mainly heats hot water supplied to the hot water tap 7 and supplies heat energy to a heating terminal 8 such as hot water floor heating and a fan convector. The hot water supplied is heated.
[0101]
The power generation device 2 includes a gas engine 5, a generator 10 driven by the gas engine 5, and a heater 11. The electric power generated in the power generation device 2 is supplied to an external load such as an electric device provided outside the system 1 and a heater 11 (internal load). The power generation device 2 includes an exhaust heat circulation circuit 12 that recovers exhaust heat by cooling the gas engine 5.
[0102]
The exhaust heat circulation circuit 12 circulates hot water via the exhaust heat exchanger 30 and the heating heat exchanger 57 on the outside of the power generation device 2, that is, on the heating device 3 side. The exhaust heat circulation circuit 12 includes an exhaust heat outward path 13 through which hot and cold water flows from the gas engine 5 to the exhaust heat heat exchanger 30 via the bypass branch point A, and hot water and a branch water path, and the hot and cold water flows toward the heating heat exchanger 57. The exhaust heat branch path 61 that flows, the exhaust heat return path 15 that returns hot water from the exhaust heat exchanger 30 to the gas engine 5 side, and the exhaust heat where the hot water that returns from the heating heat exchanger 57 joins the exhaust heat return path 15. And a branch return path 62. That is, the exhaust heat exchanger 30 and the heating heat exchanger 57 are connected to the gas engine 5 in parallel by the respective flow paths. The hot and cold water flowing in the exhaust heat circulation circuit 12 is pressure-fed by an exhaust heat circulation pump 16 provided in the exhaust heat return path 15 and flows from the exhaust heat return path 15 to the exhaust heat outward path 13. The hot and cold water flowing in the exhaust heat return path 15 is heated by heat generated by driving the gas engine 5 and flows out to the exhaust heat outward path 13.
[0103]
The heater 11 is provided in the exhaust heat outward path 13 connecting the gas engine 5 and the exhaust heat exchanger 30. The heater 11 is connected to a branch wiring 18 branched from a wiring 17 connecting the generator 10 to an external electric device or the like. Surplus power that cannot be consumed by external electric equipment or the like is supplied to the heater 11 through the branch wiring 18, thereby preventing reverse flow of power from the generator 10 to an external power supply (not shown). Have been. That is, the heater 11 is provided with a switch 21 that can be controlled by a surplus power control unit 101 described later, and by adjusting this switch 21, the power supply to the heater 11 is adjusted.
[0104]
Hot water that is heated by the exhaust heat of the gas engine 5 and flows in the exhaust heat outward path 13 is further heated when passing through the heater 11 and flows into the exhaust heat exchanger 30. The hot and cold water that has undergone heat exchange in the exhaust heat exchanger 30 and has become low temperature returns to the gas engine 5 via the exhaust heat return path 15.
[0105]
In the middle of the exhaust heat return path 15, in addition to the above-described exhaust heat circulation pump 16, a water refill tank 22 and a thermostat type three-way valve 25 are provided. Further, the three-way valve 25 is connected to a communication flow path 24 that communicates with the three-way valve 23 provided in the exhaust heat branch return path 62 described later. Further, between the exhaust heat return path 15 and the exhaust heat outward path 13, a bypass flow path 26 that bypasses both is provided. The water supply tank 22 is provided with a water supply pipe 27 for supplying water from the outside, and the amount of water supplied to the water supply tank 22 is adjusted by a water supply valve 28 provided in the water supply pipe 27. The three-way valve 25 regulates the flow of hot water to the exhaust heat exchanger 30 and the heating heat exchanger 57 in accordance with the temperature of hot water discharged from the gas engine 5.
[0106]
More specifically, when the hot and cold water discharged from the gas engine 5 side is equal to or lower than a predetermined temperature, such as immediately after the start of the gas engine 5, the three-way valve 25 operates, and the exhaust heat exchanger 30 and Water entering the heating heat exchanger 57 is prevented. That is, when the hot and cold water discharged from the gas engine 5 side is at a low temperature, the operation of the three-way valve 25 prevents water from flowing from the exhaust heat exchanger 30 and the heating heat exchanger 57 to the exhaust heat return path 15 and Thus, a closed circuit in which the exhaust heat outward path 13 and the exhaust heat return path 15 communicate with each other via the bypass flow path 26 is formed. Therefore, the hot and cold water flowing in the exhaust heat outward path 13 flows directly into the gas engine 5 via the bypass flow path 26.
[0107]
On the other hand, when the hot and cold water discharged from the gas engine 5 side is higher than the predetermined temperature, the hot and cold water flowing in the exhaust heat outward path 13 by the action of the three-way valve 25 is transferred to the exhaust heat heat exchanger 30 and the heating heat exchanger 57. Inflow. The high-temperature hot and cold water flowing into the exhaust heat exchanger 30 and the heating heat exchanger 57 exchanges heat in each heat exchanger, and then flows into the exhaust heat return path 15 via the three-way valve 23 to flow into the gas engine 5. Return to the side.
[0108]
The heating device 3 includes a combustor 6 that burns fuel gas and heats hot water and a waste heat heat exchanger 30 that performs heat exchange with hot water that is heated by exhaust heat of the gas engine 5 flowing in the exhaust heat circulation circuit 12. , A storage tank 31 (storage section). The heating device 3 includes a heat source circulation circuit 32 and a hot water supply circuit 29 for supplying hot water heated by the heat generated in the gas engine 5 and the combustor 6 to the outside via the hot water tap 7, and in addition to this, heating is performed. It has a heating circulation circuit 35 connected to a heat load such as the terminal 8 (heat load), and a reheating circuit 36 for supplying hot water and circulating water to the bathtub.
[0109]
Further, in the cogeneration system 1 of the present embodiment, a flowing water circuit (closed circuit H) including the heat source circulation circuit 32 including the heat source outward path 38 and the heat source return path 41 and the storage tank 31 is formed. Further, the cogeneration system 1 has a heat source circulation circuit 32 including a heat source outward path 38 and a heat source return path 41, a storage tank 31, and a flowing water circuit including a heat exchange branch flow path 94 branched from the heat source outward path 38. Have been. That is, the cogeneration system 1 includes a closed circuit H or a flowing water circuit including a flow path obtained by adding the heat exchange branch flow path 94 to the closed circuit H.
[0110]
The heat source circulation circuit 32 has a heat source outward path 38 connected to the outlet 37 of the combustor 6 and a heat source return path 41 connected to the inlet 40 of the combustor 6. In the heat source circulation circuit 32, a proportional valve 84 is provided on the upstream side of a branch portion D where the heat source outward path 38 is branched into a branch hot water supply flow path 83 and a tank upper pipe 87. Further, the heat source outward path 38 is further branched at a branch portion E upstream of the proportional valve 84, and a heat exchange branch flow path 94 connecting the branch portion E and the air separator 46 is formed.
[0111]
The heat source outward path 38 is branched into a branch hot water supply passage 83 connected to the mixing valve 80 at the branch part D, and a tank upper pipe 87 connected to the storage tank 31. The storage tank 31 is provided with an uppermost temperature sensor 34a, an upper temperature sensor 34b, a middle temperature sensor 34c, and a lower temperature sensor 34d in order to detect the temperature distribution in the height direction of the hot and cold water stored inside. I have. Further, in the heat source return path 41, in order from the upstream side, an air separator 46, a heat source circulation pump 47 for circulating hot water, the exhaust heat exchanger 30, a temperature sensor 48 for detecting the temperature of hot water flowing through the heat source return path 41, and a flow rate A heat source flow rate sensor 50 to be detected and a circulating water proportional valve 51 for adjusting the amount of water flowing into the combustor 6 are connected. The air separator 46 in the middle of the heat source return path 41 is for discharging the air contained in the heat source circulation circuit 32 to the outside, and is connected to a tank lower pipe 89 provided at the lower part of the storage tank 31. . Further, the exhaust heat exchanger 30 heats the hot and cold water flowing through the heat source return path 41 by performing heat exchange with hot and cold water heated by the exhaust heat generated by driving the gas engine 5 in the above-described power generator 2. is there. Therefore, while the normal gas engine 5 is being driven, the hot and cold water heated in the exhaust heat exchanger 30 flows into the combustor 6 via the heat source return path 41.
[0112]
The heat exchange section 45 is provided in the middle of the heat exchange branch flow path 94, and has a flow path 45 a having the heating heat exchanger 42 and the heating heat exchange electromagnetic valve 52, a reheating heat exchanger 43 and a reheating heat. A flow path 45b having the solenoid valve 53 is connected in parallel. Therefore, the flow and shutoff of the hot water to the heating heat exchanger 42 and the reheating heat exchanger 43 are controlled by the intermittent operation of the heating heat exchange electromagnetic valve 52 and the reheating heat exchange electromagnetic valve 53.
[0113]
The heating circulation circuit 35 connected to the heating heat exchanger 42 has a heating forward path 55 for supplying hot water to the heating terminal 8 and a heating return path 56 for returning hot water from the heating terminal 8 side. A temperature sensor 64 for detecting the temperature of hot water flowing out of the heating heat exchanger 42 is provided in the middle of the heating outward path. In the middle of the heating return path 56, a thermal valve 59 for interrupting the circulation of hot water to the heating terminal 8, a heating heat exchanger 57, a water supply tank 58 for supplying hot water to the heating return path 56, and a water supply from the heating return path 56. A temperature sensor 54 for detecting the temperature of the hot water flowing into the tank 58 and a heating circulation pump 60 for circulating the hot water in the heating return path 56 are provided. Further, the heating circulation circuit 35 has a bypass for bypassing the heating forward path 55 and the heating return path 56 in order to prevent an overload from acting on the heating circulation pump 60 and the like when the thermal valve 59 is closed. A channel 63 is provided.
[0114]
The heating heat exchanger 57 is connected to the exhaust heat branch outward path 61 branched from the exhaust heat outward path 13 of the power generation device 2 and the exhaust heat branch return path 62 branched from the exhaust heat return path 15. High-temperature hot water heated by the exhaust heat of the engine 5 circulates. Therefore, the hot and cold water that has radiated heat at the heating terminal 8 and has a low temperature is heated at the heating heat exchanger 57 by exchanging heat with the hot water and hot water supplied through the exhaust heat branch outward path 61. The hot water heated in the heating heat exchanger 57 flows into the heating heat exchanger 42 via the water refill tank 58, is further heated by heat exchange in the heating heat exchanger 42, and is then sent back to the heating terminal 8 side. .
[0115]
The reheating circuit 36 connected to the reheating heat exchanger 43 includes a reheating path 65 for feeding hot water to the bathtub side, and a reheating path 66 for returning hot water from the bathtub side. A water level sensor 67 for detecting the water level in the bathtub, a temperature sensor 69 for detecting the temperature of flowing hot and cold water, a reheating circulation pump 68, and a water flow switch 70 are provided in the middle of the reheating path 66. . Further, a pouring branch flow path 71 branched from a hot water supply flow path 33 to be described later is connected in the middle of the reheating path 66, that is, between the reheating circulation pump 68 and the water flow switch 70. The pouring water branch flow path 71 includes a check valve 72 that allows only water flow from the hot water supply flow path 33 to the reheating path 66, and a pouring valve 73 that adjusts the amount of water flowing into the reheating path 66. And a flow rate sensor 75 for detecting the flow rate of hot water flowing in the pouring branch flow channel 71.
[0116]
As described above, since the pouring branch flow path 71 that allows inflow of hot water from the hot water supply flow path 33 side is connected to the reheating path 66, Hot water can also be dropped into the bathtub.
[0117]
The hot water supply circuit 29 includes a branch hot water supply path 83 that is branched in the middle of the heat source outward path 38 and reaches the mixing valve 80, a hot water supply path 33 that extends from the mixing valve 80 to the hot water tap 7, and a hot water supply tap (not shown). The water supply flow path 85 reaching the valve 80 and the water supply flow path 91 branched from the middle of the water supply flow path 85 and reaching the bottom side of the storage tank 31 are formed in combination.
[0118]
A flow sensor 81, a proportional valve 82, and a hot water temperature sensor 95 are provided in the middle of the hot water supply passage 33. The water supply flow path 85 is provided with a pressure reducing valve 88, a check valve 90 for guiding hot and cold water to the mixing valve 80, and a water supply temperature sensor 93 for detecting the temperature of hot and cold water introduced from outside. And is connected to the mixing valve 80.
[0119]
In the middle of the water supply channel 85, a water supply channel 91 for supplying hot water introduced from the outside toward the storage tank 31 is connected. The water supply channel 91 is connected to the bottom side of the storage tank 31, and a check valve 86 for guiding hot water from the water supply channel 85 to the storage tank 31 is provided on the way. Further, a tank lower pipe 89 for discharging hot water from the storage tank 31 is connected to the bottom of the storage tank 31. The tank lower pipe 89 is connected to the heat source return path 41 connected to the inflow port 40 of the combustor 6 via the air separator 46 as described above. Further, a tank upper pipe 87 branched from the branch hot water supply channel 83 and for flowing hot water into and out of the storage tank 31 is connected to an upper portion of the storage tank 31. The storage tank 31 is supplied with almost the same amount of hot water flowing out of the storage tank 31 through the tank upper pipe 87 through the water supply passage 91, so that the storage tank 31 is always kept in a full state. Is done.
[0120]
The cogeneration system 1 according to the present embodiment includes a control unit 100 that controls the driving of the power generation device 2 and the heating device 3, and a system control unit 102 including a surplus power control unit 101. The control unit 100 transmits and receives signals necessary for control to and from the combustion control unit 103 of the power generation device 2 and the heating device 3 to open and close valves based on detection signals of the sensors, and to control pump and gas. The engine 5, the combustor 6, and the like are driven.
[0121]
Here, in the system 1 of the present embodiment, the operation state is controlled by the control unit 100 of the system control unit 102. That is, the control unit 100 manages the case where the system 1 is performing any one operation of hot water supply, heating, reheating, and dropping, or a state where a plurality of operations are performed simultaneously. Then, a control signal is transmitted from the control unit 100 to the combustion control unit 103 in accordance with the operation mode to perform necessary combustion control.
Further, in the system 1 of the present embodiment, during the heating only operation, the control unit 100 sends a heating only command signal to the combustion control unit 103. The combustion control unit 103 switches and sets the combustion pattern of the combustor 6 for heating as described in the above embodiment only when the heating only command signal is received, and when the heating only command signal is not transmitted, The combustion pattern is switched and set for hot water supply.
[0122]
The surplus power control unit 101 performs power adjustment in the cogeneration system 1. That is, the surplus power control unit 101 detects the amount of power supplied from the outside, the amount of power generated in the power generation device 2, and the amount of power consumption in electric devices connected to the power generation device 2, and detects the surplus power. In the heater 11 to prevent reverse power flow of power to an external power supply (not shown). That is, the surplus power control unit 101 detects the reverse power flow of the power to the external power supply, and turns ON / OFF the switch 21 of the heater 11 based on the detection signal. It consumes power that cannot be consumed by the connected electrical equipment and the like.
[0123]
The system control unit 102 operates the gas engine 5 and the combustor 6 in accordance with each of the above-described operations, and heats hot and cold water by the heat generated thereby. That is, the system control unit 102 determines the usage status of hot water, the usage schedule of hot water, the power status detected by the surplus power control unit 101, that is, the power generation amount in the power generation device 2, the cogeneration system 1, and the cogeneration system 1. The control unit 100 controls the driving of the gas engine 5 and the combustor 6 in accordance with the power usage status of the electric devices and the like connected to the, and heats and generates hot water.
[0124]
Next, the flow of hot and cold water in the cogeneration system 1 of the present embodiment will be described.
The cogeneration system 1 is controlled to a plurality of operating states by the system control unit 102, and the flow of hot water differs for each operation. That is, the system control unit 102 performs an exhaust heat storage operation for storing hot and cold water in the storage tank 31, a hot water supply operation for discharging hot and cold water from the hot water tap 7, a dropping operation for dropping hot and cold water into the bathtub, and Any one or more of the reheating operation for reheating and the heating operation for operating the heating terminal 8 are selectively performed.
[0125]
First, the flow of hot and cold water when performing the exhaust heat storage operation will be described with reference to FIG. When the exhaust heat storage operation is performed, the gas engine 5 starts to be driven in the power generator 2, and the exhaust heat circulation pump 16 operates accordingly, so that hot water and water start to circulate in the exhaust heat circulation circuit 12. The hot and cold water flowing in the exhaust heat circulation circuit 12 is heated by exhaust heat generated when the gas engine 5 is driven. In addition, the heater 11 is activated by surplus power that cannot be consumed by electric equipment outside the system 1 connected to the generator 10 among the power generated by the generator 10 in association with the driving of the gas engine 5. The hot and cold water flowing in the exhaust heat outward path 13 is further heated.
[0126]
When the temperature of the hot and cold water in the exhaust heat circulation circuit 12 is low, such as immediately after the start of the gas engine 5, the three-way valve 25 closes the communication passage 24, and connects the exhaust heat return passage 15 and the bypass passage 26 to each other. Operate to communicate. Therefore, the hot and cold water flowing in the exhaust heat outward path 13 flows to the exhaust heat return path 15 side via the bypass flow path 26 and circulates, and does not flow into the exhaust heat exchanger 30 or the heating heat exchanger 57 side. When the temperature of the hot water in the exhaust heat circulation circuit 12 rises to a predetermined temperature or higher as the gas engine 5 is driven, the three-way valve 23 and the three-way valve 25 are switched, and the hot water starts to circulate in the exhaust heat exchanger 30.
[0127]
On the other hand, in the heating device 3, the heat source circulation pump 47 starts driving, and hot water in the storage tank 31 flows into the heat source return path 41 from the tank lower pipe 89 provided at the bottom of the storage tank 31. The hot and cold water flowing in the heat source return path 41 is heated by performing heat exchange with hot water and hot water heated by the exhaust heat of the gas engine 5 and the heater 11 in the exhaust heat exchanger 30, and then burns from the inlet 40 of the combustor 6. Machine 6.
[0128]
In the exhaust heat storage operation, since the combustion machine 6 is in the combustion stopped state, the hot and cold water flowing in from the inflow port 40 passes through the combustion machine 6 and flows out to the heat source outward path 38 connected to the outflow port 37. Here, when the temperature of the hot water flowing into the heat source outward path 38, that is, the detection temperature of the temperature sensor 39 has not reached the predetermined temperature, the proportional valve 84 of the branch hot water supply channel 83 is closed, and the heating heat exchange electromagnetic valve is closed. At least one of the heat exchange solenoid valve 52 and the supplementary heat exchange solenoid valve 53 (the heating heat exchange solenoid valve 53 in this embodiment) is closed. As a result, hot water that has not reached the predetermined temperature does not flow into the storage tank 31, and hot water that has exited the combustor 6 flows through the flow path on the heat exchange unit 45 side and circulates in the heat source circulation circuit 32. That is, while the temperature of the hot and cold water flowing in the heat source outward path 38 is low, the heat exchange branch flow path 94 and the heat exchange path that bypass the upstream side of the proportional valve 84 in the middle of the heat source outward path 38 and the downstream side of the storage tank 31. Hot water is circulated through the exchange unit 45, and the temperature of the hot water rises.
[0129]
On the other hand, when the temperature of the hot and cold water flowing in the heat source outward path 38 becomes equal to or higher than the predetermined temperature, the proportional valve 84 is opened, and both the heating heat exchange electromagnetic valve 52 and the reheating heat exchange electromagnetic valve 53 of the heat exchange unit 45 are closed. You. Here, the mixing valve 80 is closed with respect to the branch hot water supply channel 83. Therefore, the hot water that has been heated in the exhaust heat exchanger 30 and has reached the predetermined temperature flows in from the tank upper pipe 87 connected to the upper part of the storage tank 31 and is stored in the storage tank 31. That is, the hot and cold water discharged from the tank lower pipe 89 connected to the bottom of the storage tank 31 is heated in the exhaust heat exchanger 30, and then flows in from the tank upper pipe 87 connected to the top of the storage tank 31. I do. Therefore, the hot and cold water stored in the storage tank 31 gradually becomes higher in temperature from lower to upper. That is, the hot and cold water stored in the storage tank 31 has a layered temperature distribution in the vertical direction. When substantially all of the hot water stored in the storage tank 31 has reached a predetermined temperature or higher, the storage of hot water by the exhaust heat hot water storage operation is completed. Therefore, when the lower temperature sensor 34d of the storage tank 31 reaches a predetermined temperature, the system control unit 102 determines that the hot water stored above the lower temperature sensor 34d has reached the predetermined temperature, and Complete the hot water storage operation.
[0130]
Next, the flow of hot water when the cogeneration system 1 performs the hot water supply operation will be described with reference to FIG. When hot water is sufficiently stored in the storage tank 31, when the hot water tap 7 is opened, a part of the low-temperature water supplied from the outside via the water supply channel 85 is directed toward the mixing valve 80. Supplied. On the other hand, a part of the low-temperature water supplied from the outside flows into the bottom of the storage tank 31 through the water supply channel 91 branched from the water supply channel 85. Here, the heat source circulation pump 47 provided in the middle of the heat source return path 41 is stopped or operating at a low rotation, and the proportional valve 84 is closed or the opening degree is greatly reduced. Therefore, even if hot water flows in from the bottom of the storage tank 31, almost no hot water flows out to the closed circuit H side including the heat source return path 41. Therefore, when hot water flows from the bottom of the storage tank 31, the hot water stored in the storage tank 31 is pushed upward by the hot water. As a result, high-temperature hot water on the upper side of the storage tank 31 is discharged from the tank upper pipe 87. The hot and cold water discharged from the tank upper pipe 87 flows in the branch hot water supply channel 83 and flows to the mixing valve 80 side.
[0131]
Since the mixing valve 80 is open to the branch hot water supply channel 83, the hot and cold water discharged from the tank upper pipe 87 flows into the mixing valve 80. The high-temperature hot water flowing into the mixing valve 80 is mixed with the low-temperature water supplied through the water supply flow path 85 to have an appropriate temperature, and is discharged from the hot-water tap 7 through the hot water supply path 33. That is, a temperature sensor 92 for detecting the temperature of hot water flowing out of the storage tank 31 and flowing in the branch hot water supply channel 83, a water supply temperature sensor 93 for detecting the temperature of water supplied from the outside, The mixing ratio of the hot and cold water in the mixing valve 80 is adjusted so that the temperature of the hot and cold water discharged from the hot water tap 7 becomes an appropriate temperature in accordance with the temperature detected by the hot water supply temperature sensor 95 that detects the temperature of the hot and cold water that is mixed and discharged. You. The hot and cold water mixed in the mixing valve 80 is supplied to the outside via the hot water supply passage 33 and the hot water tap 7.
[0132]
On the other hand, when the temperature of the hot water in the storage tank 31 is low, the hot water is heated by the combustor 6 and discharged from the hot water tap 7 as shown in FIG. That is, when the hot water tap 7 is opened while the temperature of the hot water in the storage tank 31 is low, the heat source circulation pump 47 is started, and the proportional valve 84 is opened. Further, the heating heat exchange electromagnetic valve 52 and the reheating heat exchange electromagnetic valve 53 in the heat exchange unit 45 are closed, and the inflow of hot water from the heat source outward path 38 to the heat exchange branch flow path 94 is prevented. Further, the mixing valve 80 is opened to a branch hot water supply passage 83 into which the hot water flowing through the heat source outward path 38 flows and a water supply flow passage 85 through which the hot water introduced from the outside flows. Therefore, a part of the low-temperature water supplied from the outside reaches the mixing valve 80 via the water supply passage 85 and flows into the hot water supply passage 33 connected to the mixing valve 80. The rest of the hot and cold water supplied from the outside is supplied from the lower part of the storage tank 31 through a water supply channel 91 branched from the water supply channel 85. When the water flow in the hot water supply passage 33 is detected by the flow sensor 81, the combustor 6 starts the combustion operation.
[0133]
Hot water flowing into the lower part of the storage tank 31 from the outside via the water supply passage 91 flows into the combustor 6 from the tank lower pipe 89 via the heat source return path 41. The hot and cold water flowing into the combustor 6 is heated by the heat generated by the combustion operation, and then flows into the mixing valve 80 through the heat source outward path 38 and the branch hot water supply path 83. The high-temperature hot and cold water flowing into the mixing valve 80 is mixed with hot and cold water supplied from the outside via the water supply passage 85 to be adjusted to an appropriate temperature, and is supplied to the outside via the hot water supply passage 33 and the hot water tap 7.
[0134]
As described above, when the hot water tap 7 is opened, the system control unit 102 operates the cogeneration system 1 in the hot water supply operation and uses the hot water in the storage tank 31 or the hot water heated by the combustor 6. Perform hot water supply. When the hot water tap 7 is closed and the flow sensor 81 stops detecting the water flow, the system control unit 102 stops the combustion operation of the combustor 6 and completes a series of operations.
[0135]
Next, the flow of hot and cold water when the cogeneration system 1 performs the dropping operation will be described with reference to FIG. The cogeneration system 1 of the present embodiment adopts a configuration in which hot water is dropped into the bath tub from the reheating path 66 in addition to the reheating path 65 when performing the dropping operation.
[0136]
In the cogeneration system 1 of the present embodiment, when the pouring valve 73 is opened and the flow rate sensor 75 detects the water flow, the dropping operation is started. When hot water is sufficiently stored in the storage tank 31, when the dropping operation is started, the temperature of the hot water dropped into the bathtub is adjusted in the same manner as in the hot water supply operation described above. That is, a part of the low-temperature water supplied from the outside via the water supply passage 85 is supplied to the mixing valve 80. On the other hand, the rest of the hot and cold water supplied from the outside flows from the bottom of the storage tank 31 through the water supply channel 91. Along with this, the hot water stored in the upper portion of the storage tank 31 is discharged from the tank upper pipe 87 and flows into the mixing valve 80.
[0137]
The high-temperature hot water that has flowed into the mixing valve 80 is mixed with the low-temperature water supplied through the water supply flow path 85, adjusted to an appropriate temperature, and flows out to the hot water supply flow path 33. The hot and cold water flowing into the hot water supply flow path 33 flows through the pouring water branch flow path 71 branched from the hot water supply flow path 33 and flows into the additional heating return path 66. Here, in the case of the drop-down operation, since the additional heating circulation pump 68 is stopped, a part of the hot water flowing into the additional heating return path 66 flows into the bathtub through the additional heating return path 66. In addition, the remaining portion of the hot water that has flowed from the pouring branch passage 71 into the reheating path 66 flows around the reheating heat exchanger 43 and flows into the bathtub from the reheating path 65. When the water level sensor 67 detects that the water level in the bathtub has reached a predetermined water level, the pouring valve 73 is closed, and a series of dropping operations is completed.
[0138]
Next, the flow of hot water in the reheating operation in which the hot water in the bathtub is reheated will be described with reference to the operation principle diagram shown in FIG.
The detailed control of each part in the reheating operation is the same as the control in the heating device 3 shown in the embodiment. In the reheating operation, the hot water in the bathtub is reheated by heat exchange between the hot water heated by the combustion operation in the combustor 6 and the reheating circuit 36 in which the hot water in the bathtub circulates.
[0139]
More specifically, when the cogeneration system 1 starts the reheating operation, the reheating circulation pump 68 is driven. Accordingly, when the water flow switch 70 detects that the flow rate of the hot and cold water in the follow-up return path 66 is a predetermined amount, the heat source circulation pump 47 provided in the heat source return path 41 is activated, and the combustor 6 is activated. At this time, the heating and heat exchange electromagnetic valve 52 is closed, and the reheating heat exchange electromagnetic valve 53 is opened. Thus, in the reheating operation, the hot and cold water discharged from the combustor 6 passes through the heat source return path 41, passes through the heat source return path 41, passes through the heat source return path 41, and passes through the heat source return path 41, as shown in FIG. Circulate on the route back to 6. That is, in the reheating operation, the hot water heated in the combustor 6 circulates through the reheating heat exchanger 43 provided in the flow path 45b. The hot and cold water circulating in the reheating circuit 36 with the driving of the reheating circulation pump 68 is heated by exchanging heat with the high-temperature hot water heated in the combustor 6 in the reheating heat exchanger 43.
Then, when the off-operation of the reheating operation is performed by the remote controller or when the temperature sensor 69 of the reheating return path 66 reaches the temperature set by the remote controller, a series of the reheating operation ends.
[0140]
Subsequently, the flow of hot and cold water in the heating operation for driving the heat load of the heating terminal 8 and the like will be described with reference to FIGS. 15 and 16.
The detailed control of each part in the heating operation is the same as the control in the heating device 3 shown in the embodiment. When the cogeneration system 1 starts the heating operation, the heating circulation pump 60 is activated, and the hot water starts to circulate in the heating circulation circuit 35. Here, when the temperature detected by the temperature sensor 54, that is, the temperature of the hot water returned from the heating terminal 8 side is equal to or lower than a predetermined temperature, the gas engine 5 starts to heat the hot water circulating in the heating circulation circuit 35. . Further, when the temperature of the hot water returning from the heating terminal 8 side is extremely low, or when the set temperature in the heating terminal 8 is high, the combustor 6 starts in addition to the gas engine 5. That is, in the heating operation, the hot and cold water circulating in the heating circulation circuit 35 is heated by the heat exchange in the heating heat exchanger 57, and in some cases, the heat exchange in the heating heat exchanger 42 is performed to perform the heating exchange. Heat the hot and cold water circulating inside.
[0141]
More specifically, as shown in FIG. 15, when the gas engine 5 of the power generation device 2 is started, the exhaust heat circulation pump 16 operates to circulate the hot water in the exhaust heat circulation circuit 12. The hot and cold water flowing in the exhaust heat circulation circuit 12 is heated by exhaust heat generated by driving the gas engine 5 and becomes high temperature. In addition, the heater 11 is driven by the electric power generated in the generator 10 with the driving of the gas engine 5, and the hot and cold water flowing in the exhaust heat outward path 13 is further heated.
[0142]
While the temperature of the hot and cold water in the exhaust heat circulation circuit 12 is low, the three-way valve 23 and the three-way valve 25 of the thermostat type operate the exhaust heat outward path 13, the bypass flow path 26, and the exhaust heat return path 15. The hot water circulates. When the hot water flowing in the exhaust heat circulation circuit 12 is heated to a predetermined temperature or higher, the hot water flows in the exhaust heat branch forward path 61 and the exhaust heat branch return path 62 by the action of the three-way valve 23 and the thermostat type three-way valve 25, Hot water is supplied to the heating heat exchanger 57. Hot water returned from the heating terminal 8 via the heating return path 56 is heated by exchanging heat with high-temperature hot water supplied from the power generation device 2 side in the heating heat exchanger 57. Here, when the temperature detected by the temperature sensor 54 on the downstream side of the heating heat exchanger 57 is the set temperature of the heating terminal 8, the hot water heated in the heating heat exchanger 57 is sent to the heating heat exchanger 42 side. The heat is supplied to the heating terminal 8 via a heating outward path 55 connected to the heating heat exchanger 42.
[0143]
On the other hand, when the temperature of the hot water returning from the heating terminal 8 side is low, or when the set temperature in the heating terminal 8 is high, that is, only by performing heat exchange in the heating heat exchanger 57, the set temperature of the heating terminal 8 is not reached. In this case, as shown in FIG. 16, the driving of the combustor 6 is started, and the heat source circulation pump 47 starts driving. When the heat source flow sensor 50 detects flowing water in the heat source circulation circuit 32, the combustion operation in the combustor 6 is started. Hot water heated by the combustion operation in the combustor 6 and heated to a high temperature passes through the heating heat exchanger 42 in the flow path 45a of the heat exchange unit 45, returns to the combustor 6 side, and passes through the heating circulation circuit 35. To supply heat to the heating terminal 8.
Then, when the off operation of the heating operation is performed by the remote controller, a series of reheating operations is completed.
[0144]
In the above-described embodiment, the case where each operation is performed independently in the cogeneration system 1 is illustrated. However, the present invention is not limited to such a single operation, and the reheating and heating shown in the embodiment is performed. Each operation such as simultaneous operation and simultaneous operation of hot water supply and heating can be performed simultaneously.
[0145]
In the above-described embodiment, the cogeneration system 1 including the gas engine 5 and the combustor 6 as the heat source for heating the hot and cold water is illustrated, but more heat source units may be provided. That is, it is also possible to adopt a configuration in which a plurality of heat source units for mainly heating hot water in the storage tank 31 and a plurality of heat source units for mainly heating hot water used for hot water supply, heating, and reheating are provided.
[0146]
Further, in the above embodiment, as shown in FIG. 10 described above, an example in which the storage operation using the exhaust heat by the power generation device 2 is performed, but the present invention is not limited to such a configuration. It is also possible to store hot water in the storage tank 31 while driving the combustor 6 to perform the reheating operation, or to store hot water in the storage tank 31 while driving the combustor 6 to perform the heating operation. It is possible.
Further, for example, when a failure occurs in the power generator 2, it is possible to drive the combustor 6 to perform the storage operation instead of using the exhaust heat. Similarly, when the power generation device 2 fails, the heating can be performed by driving the combustor 6 instead of the heating using the exhaust heat shown in FIG.
[0147]
【The invention's effect】
According to the invention as set forth in claims 1 to 4, heat can be supplied while burning the combustor with an optimal combustion amount according to each heat load of hot water supply and heating, and stable while improving operation performance. A heating device that performs combustion control can be provided.
According to the fifth and sixth aspects of the present invention, it is possible to provide a cogeneration system in which the total energy efficiency is improved by using the heating device according to the first to fourth aspects and the system construction is facilitated.
[Brief description of the drawings]
FIG. 1 is a flow path system diagram of a heating device according to an embodiment of the present invention.
FIG. 2 is a flowchart showing control of the heating device shown in FIG. 1 relating to a hot water supply operation and a heating operation.
FIG. 3 is a flowchart showing control of the hot water supply independent operation of the heating device shown in FIG. 1;
FIG. 4 is a flowchart showing control of a heating alone operation of the heating device shown in FIG. 1;
FIG. 5 is a flowchart showing hot water supply control during simultaneous operation of hot water supply and heating of the heating device shown in FIG. 1;
6 is a flowchart showing heating control during simultaneous operation of hot water supply and heating of the heating device shown in FIG. 1.
FIG. 7 is a flowchart showing a stabilization determination process of the hot water temperature of the combustor in the flowcharts of FIGS.
FIG. 8 is a flowchart showing a process of adjusting the set temperature of the combustor in the flowcharts of FIGS. 4 and 6;
FIG. 9 is a flow channel diagram of a cogeneration system according to an example of the present invention.
10 is an operation principle diagram in the case of performing a waste heat storage operation in the cogeneration system of FIG. 9;
11 is an operation principle diagram in the case of performing a hot water supply operation using hot water stored in a storage tank in the cogeneration system of FIG. 9;
12 is an operation principle diagram in a case where a hot water supply operation is performed by driving a combustor in the cogeneration system of FIG. 9;
FIG. 13 is an operation principle diagram in the case of performing a bath dropping operation in the cogeneration system of FIG. 9;
FIG. 14 is an operation principle diagram in the case of performing the reheating operation of the bath in the cogeneration system of FIG. 9;
FIG. 15 is an operation principle diagram in a case where a heating operation is performed using waste heat of the power generation device in the cogeneration system of FIG. 9;
16 is an operation principle diagram in a case where a heating operation is performed by exhaust heat of a power generation device and heating of a combustor in the cogeneration system of FIG. 9;
[Explanation of symbols]
1 Cogeneration system
2 Power generator
3 heating device
6. Combustor (heat source)
7 Hot water supply terminal (hot water tap)
8 heating terminal
12 Waste heat circulation circuit
29 Hot water supply circuit
30 Exhaust heat exchange unit (Exhaust heat exchanger)
31 Storage unit (storage tank)
32 Heat source circulation circuit
33,83 Hot water supply channel (branch hot water supply channel)
35 heating circuit (heating circulation circuit)
36 Reheating circuit (recirculation circuit)
42 heat exchanger (heating heat exchanger)
43 heat exchanger (reheating heat exchanger)
85, 91 Water supply channel
102 System control unit
103 Combustion control unit

Claims (6)

A heat source circuit connected to an externally provided hot water supply terminal and a heating unit connected to an externally provided heating terminal are provided in a heat source circulation circuit for circulating hot water heated by one or more heat source units including a combustor. A heating device in which a circuit is connected directly or via a heat exchanger to supply hot water to a hot water supply terminal and / or supply heat energy to a heating terminal at the same time. During the heating alone operation, the combustor is burned in a combustion pattern corresponding to the thermal energy required by the heating terminal of the heating circuit, and in other operations except the heating only operation, the combustor is driven by the hot water supply terminal of the hot water supply circuit. A combustion device that burns in a combustion pattern corresponding to the heat energy required. When shifting from the other operation except the heating only operation to the heating only operation, in the heating only operation, the combustion pattern of the combustor during the period in which the combustor has stopped combustion is a combustion pattern according to the hot water supply terminal. 2. The heating device according to claim 1, wherein the combustion pattern is switched to a combustion pattern according to the heating terminal. The heating device according to claim 1 or 2, wherein a reheating circuit connected to the bath terminal is connected to the heat source circulation circuit via a heat exchanger in parallel with the hot water supply circuit and the heating circuit. The hot water supply circuit is formed by combining a hot water supply flow path for supplying hot water to an externally provided hot water supply terminal or bath terminal and a water supply flow path for receiving water supply from an externally provided water supply terminal. The heating device according to any one of claims 1 to 3, further comprising a storage unit configured to store hot and cold water heated in the heat source circulation circuit between the heating device and a passage. A cogeneration system provided with a power generation device for supplying electric power to an electric device to the heating device according to any one of claims 1 to 4, wherein the power generation device heats waste heat generated by power generation as a heat medium. Has a waste heat circulation circuit that circulates heat by exchanging heat, a waste heat heat exchange part is interposed between the waste heat circulation circuit and the heat source circulation circuit, and one of the heat source parts is a waste heat heat exchange part. A cogeneration system characterized by being formed. The cogeneration system according to claim 5, further comprising a system control unit that controls the heating device and the power generation device, wherein the heating device includes a combustion control unit that controls combustion of a combustor, and the cogeneration system includes a heating unit. A cogeneration system, wherein when performing an isolated operation, a heating independent command signal is transmitted from the system control unit to the combustion control unit.

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